A11105 S11157 o'iA'i IVUUia w 1 “fctT'J

Corrosion Evaluation of

Underground Telephone Cable

Shielding Materials

W. F. Gerhold and J. L. Fink

Chemical Stability and Corrosion Division

Center for Materials Science

U.S. Department of Commerce

National Bureau of Standards

Washington, DC 20234

April 1981

Progress Reoort

1976-1980

\ &

t

>

t

k

HOC100

U^b

81-2243

Prepared for Rural Electrification Administration

irtrrsent of Agriculture

lington, DC 20250
1

I
IUT10NAL BVRKKV

OF STANDAHUS

LlRRARV

NBSIR 81-2243 DEC 7 1981

/lOti Clcc - CORROSION EVALUATION OF

UNDERGROUND TELEPHONE CABLE

SHIELDING MATERIALS

W. F. Gerhold and J. L. Fink

Chemical Stability and Corrosion Division

Center for Materials Science

U.S. Department of Commerce

National Bureau of Standards

Washington, DC 20234

April 1981

Progress Report

1976-1980

DISTRIBUTION OF THIS DOCUMENT IS UNLIMITED

Prepared for Rural Electrification Administration

Department of Agriculture

Washington, DC 20250

U.S. DEPARTMENT OF COMMERCE, Malcolm Baldrige, Secretary

NATIONAL BUREAU OF STANDARDS. Ernest Ambler. Director
tXjfy AKOr; aw

v»#»* >.t

k ‘
CORROSION EVALUATION OF UNDERGROUND TELEPHONE CABLE SHIELDING MATERIALS

William F. Gerhold and James L. Fink

Corrosion and Electrodeposition Group

Chemical Stability and Corrosion Division

National Bureau of Standards

Washington, DC 20234

INTRODUCTION

An increase in underground telephone cable installation by the telephone

industry throughout the United States has created a demand for comprehensive

and reliable information with respect to the corrosion of shielding materials.

In order to obtain such corrosion data on both currently accepted and proposed

experimental cable systems, the National Bureau of Standards and the Rural

Electrification Administration initiated a six-year underground corrosion

program. The program was initiated in 1968 with the burial of thirty-one cabl

systems in selected soil environments. A paper summarizing the results for

specimens buried for one year was given at the 18th International Wire and

Cable Symposium [1]. During the period since the first report and the present

time, many additional systems utilizing metals or plastic coated metals have

been incorporated into the program. Other papers were presented at the

Corrosion/74 [2] and Corrosion/76 Symposia [3] summarizing the results

obtained for these materials and the additional systems after burial for

periods of up to six years in soil environments. This paper (the fourth

report) contains additional data for some of the systems included in the

earlier reports and results obtained for systems buried over the years

since the last report. Table 1 describes the various cable systems included

in this report.
2

SOILS AT THE TEST SITES

The chemical and physical properties of the soils at the test sites are

given in table 2. The chemical properties listed show that the soils differ

widely with respect to their composition and the concentrations of soluble

salts they contain. The pH of the soils range from extreme acidity (4.0)

to high alkalinity (8.8). The electrical resistivity of the soils range from

55 ohm-cm, which is approximately that of sea water, to 30,000 ohm-cm,

indicating the absence of soluble salts. The physical conditions of the soils

range from well aerated to very poorly aerated.

These widely differing soil environments allow for a comprehensive soil

corrosion program. The soils included are moderately corrosive (Sites B and

D) to very corrosive (Sites A, C, E, and G) toward ferrous and other metals.

The soils cover a wide range of soil properties, with respect to corrosion,

found throughout the United States. Furthermore, it is possible to correlate

corrosion data from these six soils with data previously obtained from 128

test sites in which the National Bureau of Standards has conducted extensive

investigations on the underground corrosion of metals and alloys [3].

Descriptions of the soils at the six test sites are as follows:

Sagemoor sandy loam (Site A) is a well -drained alkaline soil and is

typical of that found in vast areas of eastern Washington and Oregon. The

site is located on the Yakima Indian Reservation near Toppenish, Washington.

The soil is consistent in composition to a depth of at least seven feet and

supports abundant growth of sage brush.

Hagerstown loam (Site B) is a well -drained soil representative of the

majority of wel 1 -developed soils found in the eastern part of the United

States. The site is located at the Loch Raven Reservoir of the Baltimore City
Water Department. The soil consists of a brown loam about one foot deep,

underlain by a reddish-brown clay that extends five feet or more to underlying rock. Practically all of the materials that have been investigated

in the extensive NBS soil corrosion tests since 1922 have been exposed at

this site and, therefore, it can serve as a reference site for the correlation of data obtained for specimens in the present program with data obtained

from the earlier tests.

Clay soil (Site C) . This site is located in a large clay pit on level

land at the U.S. Coast Guard Receiving Center at Cape May, New Jersey. The

soil consists of a plastic gray clay to a depth of twelve inches. This is

underlain by a poorly drained very heavy plastic clay to which the specimens

are exposed.

Lakewood sand (Site D) is a white, loose sand with some black streaks

occurring in places and supports an abundant growth of beach grasses. The

site is located in a well-drained rolling area on the property of the U.S.

Coast Guard Electronic Engineering Station at Wildwood, New Jersey. The area

is not subject to overflow from the ocean except under unusual flood conditions.

Coastal sand (Site E) is a typical white, coastal beach sand with a

high content of black sand that occurs in streaks. This sand is similar to

Lakewood sand, except that at this site, the sand is continuously saturated

with salt water. The site is located on the Two-mile Beach on the property

of the U.S. Coast Guard Electronic Engineering Station, Wildwood, New Jersey.
4

Tidal marsh (Site G) is a soil typical of the poorly-drained marsh

soils that are found along the Atlantic and Gulf coasts and is charged with

hydrogen sulfide. The site is located along a creek that empties into the

Chesapeake Bay at Lexington Park, Maryland, on the property of the U.S.

Naval Air Training Center.

TEST PROCEDURE

In order to expose the shield material to the environment and to

simulate conditions which may occur in field installations of telephone

cables, specimens were prepared as shown in figure 1. Specimens used in

this study were polyethylene jacketed cable lengths [approximately fourteen

inches (35.6 cm) long] containing metallic or plastic coated metal shields.

With a few exceptions, the shield was exposed by stripping the outer polyethylene

protective jacket at two areas, one each approximately four inches (10.2

cm) from either end of the cable length, creating a window and a ring. The

window was an exposed area along the length of the cable approximately two

inches (5 cm) long x 0.5 inch (1.3 cm) wide, while the ring was an exposed

area 0.5 inch (1.3 cm) wide around the circumference of the cable. In

addition, some of the systems were electrically coupled to copper strips by

mechanically bonding the strip to electrical wires which were in turn

mechanically bonded to the shield at the ends of the cable. Coupling the

shield to copper thus created a galvanic cell between the copper and the

shield material. This was done to simulate field conditions in which

dissimilar metal shields may be coupled either to existing cable systems

having copper shields or to copper ground rods. The ends of the specimens

were sealed with a sealing compound and wrapped with vinyl tape to prevent

entry of moisture at the end areas.
5

With a few exceptions six specimens of each system were buried at each

of the six soil sites. All specimens were buried at a depth of approximately

three to four feet (0.9 to 1.2 m) below the ground line in trenches two feet

(0.6 m) wide.

Each year a replicate specimen was withdrawn from each of the burial

sites for cleaning and examination.

Five areas on each of the specimens were examined and rated numerically

in accordance with table 3. These areas were the exposed window, the exposed

ring, the jacketed area one-half inch around the exposed window, the jacketed

area one-half inch around the exposed ring, and the remainder of the jacketed

shield. In the case of composite and clad materials, the outer, middle, and

inner shields were rated individually.

RESULTS

The results obtained from the evaluation of cable specimens exposed for

periods up to six years in various underground soil environments are summarized

in tables 4 through 9. As previously noted, areas of the shields were given

numerical ratings to indicate the extent of degradation due to corrosion.

These ratings are described in table 3. A rating of ten indicates that the

shield was unaffected by corrosion, while a rating of zero indicates severe

corrosion, where metal loss through corrosion was sufficient to cause longitudinal electrical discontinuity (ELD) of the shield. When the shield

exhibited ELD at all areas measured, it was considered to be destroyed. It

was noted that degradation of some specimens exposed for shorter periods of

time was much more severe than that observed on similar specimens exposed

for greater periods of time. This may be partially explained by the methods

used in preparation of the specimens. If the cut through the outer jacket
6

made to expose the window and ring was deep enough to penetrate the shield,

it could allow corrosion of the inner shield materials. On the other hand,

if the depth of cut was such that only the outer jacket was slit, then the

integrity of the shield materials could be maintained. The following describes

the various systems and their performance in the six soil environments in

which the specimens were exposed.

System 41 . This system consisted of a 25-pair, 22-gauge cable having

an uncorrugated 8-mil 1100 aluminum alloy shield. This was a filled cable

(polyethylene, 15 percent petroleum jelly, 85 percent by volume in conductor

interstices and on both sides of the shield).

In general, the filling compound was tacky except at areas where the cable

was corroded.

Specimens of this system were buried at Sites A, C, and G only.

There was no significant degradation of the shields of specimens exposed

for up to six years at Site A. The shields of specimens of this system

exposed at Site C were ELD after exposure for three years, while for those

buried at Site G the shield was perforated due to corrosion in less than

one year and were considered destroyed on specimens buried for four to six

years.

System 42 . This system is the same as System 41 except that the shield

was coupled to copper.

Specimens of this system were also buried only at Sites A, C, and G.

Coupling the specimens to copper accelerated the corrosion of the

shields.

After exposure for one year at Site A, the shield was ELD at several

areas. Examination of specimens retrieved from this site after exposure

for two to six years revealed that all were ELD at all areas rated. Specimens

exposed at Sites C and G for up to six years were also ELD at all areas rated.
System 43 . This system consisted of a 100-pair, 19-gauge cable having

an 8-mil corrugated 1100 aluminum alloy inner and outer shield with a polyethylene jacket bonded to the inner sides of both shields.

Specimens were exposed at Sites A, C, and G only.

The outer and inner shields of specimens exposed for up to six years

at Site A were not significantly affected by corrosion.

After exposure for two and three years at Sites C and G both shields

were ELD at window and/or ring areas. The outer shields were ELD or near ELD

at jacketed areas on specimens buried at these sites for two to six years.

The inner shields of specimens buried for four to six years were unaffected

by corrosion.

System 44 . This system was the same as System 43 except that the system

was coupled to copper.

Corrosion of the aluminum shields was accelerated due to the galvanic

effect between the copper and aluminum.

The outer aluminum shields were ELD or near ELD on all specimens exposed

at Sites A, C, and G for up to six years. With one exception the inner

shields of these specimens at jacketed areas were relatively unaffected by

corrosion. The inner shield of the specimen buried at Site A for five years

was perforated due to localized pitting corrosion. The outer and inner

shields of specimens exposed for up to three years at these sites were

severely corroded at the exposed window and ring. Most were ELD at these

areas.

System 45 . This system consisted of a 100-pair, 22-gauge cable. The

shield was 8-mil uncorrugated 1100 aluminum alloy, coated with resin on both

sides and was bonded to the jacket.
8

Specimens of this system were buried at Sites A, C, and G only.

The shields of specimens buried for up to six years at Site A were

unaffected by corrosion. Specimens buried at Site G were severely corroded

at jacketed and unjacketed areas after exposure for one year. After exposure for three years, the shield was ELD or near ELD at jacketed and un jacketed

areas. The shields of the specimens exposed for five and six years was ELD

at all areas rated.

Corrosion of the specimens buried for up to three years at Site C was

less severe but the shields were perforated by corrosion at several areas.

After exposure for four to six years, the shields were ELD or near ELD at

jacketed and un jacketed areas.

System 46 . This system is the same as System 45 except that the shield

was coupled to copper.

Specimens of this system were exposed at Sites A, C, and G only.

Coupling the specimens to copper accelerated the corrosion of the aluminum shield in all of the soils.

The shield of the specimen buried for one year at Site A was perforated

at window and ring areas due to localized pitting corrosion. Examination

of specimens exposed for from two to six years showed that all were ELD at

all areas rated.

Specimens at Sites C and G were severely corroded at jacketed and unjacketed

areas. The shields of the specimens buried for four and five years at Site C

were ELD at all areas rated, while the specimen buried for six years at this

site was near ELD at all areas rated. The shields of specimens of this

system buried at Site G for one, three, and four years were perforated by

corrosion at all areas rated. The shields on companion specimens buried

for two, five, and six years were considered destroyed.
System 47 . This system consisted of a 3-mil corrugated Type 304 stainless steel outer shield bonded to a 6-mil corrugated aluminum inner shield

which was vinyl coated on both sides.

Delamination of the outer and inner shields particularly at the edge

seam was observed on most of the specimens exposed to the various soil

environments.

With a few exceptions, the outer stainless steel shield of specimens

exposed for up to six years at all sites was unaffected by corrosion. Pitting

corrosion of both shields was observed at the exposed window on the specimen

buried for one year at Site C. Both shields were perforated by corrosion on

specimens buried for one and two years at Site G. With the exception of some

specimens buried at Sites B and D, the inner aluminum shields were affected

by corrosion in varying degrees particularly at window and ring areas. This

is attributed to penetration by moisture at the seam edges.

The inner shields on specimens exposed at Site A for up to five years

were severely corroded at the exposed window. After exposure for two years

the shield was near ELD and after exposure for four years the shield was ELD.

The inner shield of the specimen exposed for six years was perforated due to

localized pitting corrosion at all areas rated.

Localized pitting corrosion with subsequent perforation of the inner

shield was noted at unjacketed ring areas of the specimen exposed at Site B

for one year and at jacketed window areas of the specimen buried at this site

for two years.

The inner shields of specimens buried at Site C for two and three years

were severely corroded at the exposed window. After exposure for three and

five years the shield was near ELD at this area. There was no corrosion of
the inner shield at jacketed areas on specimens buried for two and three

years, while the shields of specimens buried from four to six years were

perforated due to localized pitting corrosion at these areas.

The inner shields of specimens buried for up to three years at Site D

and up to two years at Site E were relatively unaffected by corrosion. After

exposure for four and six years at these sites the shields were perforated

by localized pitting corrosion at all areas rated.

The inner shields of specimens exposed for two years at Site G were

ELD at jacketed and unjacketed window areas. After exposure for up to six

years the shield was ELD or near ELD at all areas rated.

System 48 . This system is the same as System 47 except that the system

was coupled to copper.

As noted for System 47 delamination of the outer and inner shields

at edge seam areas was also observed on most specimens of this system.

There was no significant corrosion of the outer stainless steel shield

on specimens exposed for up to six years at Sites A, B, C, D, and E. The

outer shields of specimens exposed for one and three years at Site G were

perforated at window areas due to localized pitting corrosion. The shields

were ELD at these areas on specimens buried at this site for two and four

years.

With the exception of some of the specimens exposed at Sites B, D, and

E, the inner aluminum shields were affected in varying degrees by corrosion.

After exposure for three and four years, the inner shield was perforated due

to localized corrosion at unjacketed window and/or ring areas of specimens

buried at Site B and at jacketed and un jacketed areas on specimens buried

at Site D. The inner shield of the specimens buried for four years at Site E

was severely corroded at the unjacketed window and at the jacketed ring.
The inner shields of companion specimens buried for five and six years at

this site were ELD at the unjacketed windows. The inner shields of the

specimens buried for three and five years at Site A were ELD at the exposed

window, while at the exposed ring, jacketed window and ring areas, corrosion

was less severe. The shield of a companion specimen exposed for four years

at this site was perforated due to localized pitting corrosion at unjacketed

areas but was unaffected by corrosion at jacketed areas. The inner shield

of the specimen buried for six years was ELD at the jacketed area.

After exposure for two years at Site C the inner shield was ELD at the

jacketed window and ring areas. Corrosion of the inner shield of a companion

specimen buried for six years was ELD at jacketed and unjacketed areas.

The inner shields of specimens buried for two to six years at Site G

were ELD or severely corroded at all areas rated.

System 49 . This system consisted of a 3-mil corrugated Type 304 stainless steel outer shield bonded to a 4-mil corrugated 1100 aluminum alloy

inner shield which was vinyl coated on both sides.

The outer and inner shields had delaminated at the edge seam on nearly

all specimens.

The specimens buried for up to four years at Site B were unaffected by

corrosion.

The outer stainless steel shields were unaffected by corrosion after

exposure for two years at Site G and up to six years at Sites A, C, D, and

E. The outer shield on specimens buried for three, four, and six years at

Site G were severely corroded at the window areas. There was no apparent

corrosion of the inner shields of specimens exposed for one year at Sites A,

B, and C, up to two years at Sites D and E, and up to six years at Site B.
12

The inner shields of specimens buried for two to six years at Sites A and

C were perforated at exposed window and/or ring areas. After exposure for

six years the shields of specimens exposed at these sites were perforated

by corrosion and were ELD at the exposed window areas.

The inner shields or specimens exposed at Site D for three to six years

were perforated at window and ring areas due to localized pitting corrosion.

The shields of these specimens at other jacketed areas were unaffected by

corrosion.

After exposure for six years at Site E, the inner aluminum shield was

perforated at all areas rated.

Of the specimens exposed at Site G for two to six years, the inner

shields were ELD at jacketed and un jacketed areas.

System 50 . This system is the same as System 49 except that the system

was coupled to copper.

The outer and inner shields of most specimens were found to be delaminated

after exposure in the various soils.

With one exception, the outer stainless steel shield was relatively

unaffected by corrosion after exposure up to six years at Sites A, B, C, D,

and E. The outer shield was perforated due to localized pitting corrosion

at the un jacketed window on the specimen exposed for four years at Site C.

Of the specimens exposed for up to six years at Site G, the outer shields were,

with a few exceptions, perforated due to localized pitting corrosion.

The inner aluminum shields of specimens buried for two years at Site A,

one to five years at Site B, and one and two years at Sites D and E were

unaffected by corrosion. The inner shields of specimens exposed at Site A

for three and four years were perforated by corrosion which was more severe

at window and ring areas. After exposure for four and six years, the inner
shield was ELD at the exposed window. The inner shield was near ELD at the

window on the specimens exposed for up to three years at Site C. After

exposure for four to six years at this site, the inner shields were ELD at

most of the areas rated. The inner shields of specimens buried for four

years at Site D and three years at Site E were near ELD at the exposed

windows. After exposure for four years at Sites D and E, this shield was

perforated due to localized pitting corrosion at all areas rated. The

inner shields on specimens exposed for up to six years at Site G were in

general ELD or near ELD at jacketed and un jacketed areas.

System 51 . This system is the same as System 47 except that the adhesive

used to bond the outer and inner shield was an epoxy base compound.

The outer and inner shields of nearly all specimens buried in the various

soils were delaminated.

With a few exceptions the outer shields of the specimens exposed at

Sites A, B, C, D, and E were unaffected by corrosion. Of the specimens

exposed at Site G, the outer shields were perforated due to localized

pitting corrosion which occurred generally at the unjacketed window.

The inner shields were ELD or near ELD at the exposed window for two

to four years at Site A. Of the specimens buried for up to six years at

Site C most were ELD or near ELD at both jacketed and un jacketed areas. The

inner shields on specimens buried at Site D for three to six years, and

Site E for two to six years were with a few exceptions perforated due to

localized pitting corrosion which was observed at jacketed and unjacketed

areas. In general, the inner shield on specimens buried at Site G was ELD

at all areas rated after exposure for one year.

System 52 . This system is the same as System 51 except that the system

was coupled to copper.
Del ami nation of the outer and inner shields was noted on nearly all

specimens examined.

The outer shields of specimens exposed for up to four years at Sites A,

B, C, D, and E were, with one exception, unaffected by corrosion. The shield

on the specimen buried for four years at Site B was perforated due to

corrosion at the unjacketed window and the jacketed ring.

In general varying degrees of corrosion were observed on the inner shield

on all specimens after burial for up to six years in the soils. However,

there was no corrosion observed on specimens buried for one year at Sites A

and D, and up to two years at Site B. The shields were ELD after burial

for two years at Sites A, C, and G, and three years at Sites D and E.

System 53 . This system was a 25-pair, 19-gauge filled cable and consisted of an 8-mil 1100 aluminum alloy shield adhesive bonded on both sides

with 1.5 mil polyethylene. There was no window or ring on specimens of this

system. The conductors were removed from the cable leaving a hollow shell.

Specimens of this system were buried at Sites A, C, D, E, and G only.

There was no apparent degradation of the shields after exposure in any of

the soils for up to five years.

System 54 . This system is the same as System 53 except that the system

was coupled to copper. There was no window or ring on specimens of this

system. The conductors were removed from the cable leaving a hollow shell.

Specimens of this system were buried at Sites A, C, D, E, and G only.

This system was unaffected by corrosion after one and two years exposure

at any of these sites. With two exceptions there was little or no degradation

of the shield after exposure for up to six years. On one specimen buried for

three years at Site C, the shield was near ELD. The shield of the specimen

buried for four years at Site E was perforated due to localized pitting

corrosion at the seam areas.
System 55 . This system consisted of a 4 inch x 9 inch x 0.008 inch

sheet of 8-mil 1100 aluminum alloy bonded on both sides with 1.5 mil polyethylene.

Specimens of this system were unaffected by corrosion after burial for

up to six years at Site E. The aluminum was perforated by corrosion on

specimens exposed for two years at Sites B, C, and G, four years at Site D,

and five years at Site A.

System 56 . This system consisted of a 3-mil Type 430 stainless steel

outer shield bonded to a 3-mil 1100 aluminum alloy inner shield with a clear

flooding compound on the core side.

Specimens of this system were exposed at Sites A, C, D, E, and G only.

Delamination of the outer and inner shields was noted on nearly all of

the specimens examined.

There was no degradation of the outer or inner shields on specimens

exposed for six years at Site A and five years at Site D, or of the outer

shield on specimens buried for up to six years at Site C and four years at

Site E. The outer shield was ELD or near ELD at the unjacketed window

and/or ring on specimens buried for four and six years at Site G. The

inner shields were perforated due to localized corrosion after burial for

four and six years at Site C and three and four years at Site E. In general

the inner shield was ELD or near ELD on specimens exposed for from two to

six years at Site G.

In general, the filling compound was tacky except at areas on the shields

where corrosion was observed.
System 57 . This system is the same as System 56 except that the system

was coupled to copper.

Specimens of this system were exposed at Sites A, C, D, E, and G only.

As noted for System 56, there was delamination of the outer and inner

shields on nearly all specimens examined.

In general there was no degradation of the outer shield on specimens

buried for up to six years at Sites A, C, D, and E. Localized pitting

corrosion was noted on the outer shield of one specimen exposed for one year

at Site A. Two outer shields were perforated due to corrosion at unjacketed

window or ring areas on specimens buried at Site C for five and six years.

There was no degradation of the inner shield on specimens buried from

two to six years at Site A and one year at Site C. Of the specimens buried

at Site C for three to six years the inner shield was ELD or near ELD at

jacketed and unjacketed areas. Similarly, the inner shield of specimens

buried at Site D for three and six years and Site E for two and four years

were ELD at the un jacketed window.

Both the outer and inner shields were ELD after burial for two years

at Site G.

The filling compound was tacky except at areas where the shields were

corroded.

System 58 . This system consisted of a 3-mil (0.08 mm) Type 304 stainless

steel shield with 4-mil (0.10 mm) vapor deposited aluminum coating on the

outer surface.

Specimens of this system were exposed at Sites A, C, E, and G only.

With one exception, degradation of the stainless steel was nil or superficial for specimens buried at Sites A, C, E, and G for up to five years.

On one specimen buried at Site G for five years the stainless steel shield

was perforated due to localized pitting corrosion at the un jacketed window.
The vapor deposited aluminum was dissipated in varying degrees at

all of the sites. At Site A the coating was at or near ELD after exposure

for two years and was ELD after exposure for four years. The coating was

ELD at Sites C and G after exposure for two years and at Site E after

exposure for three years.

System 59 . This system is the same as System 58 except that the system

was coupled to copper.

Specimens of this system were exposed at Sites A, C, E, and G only.

With one exception, there was no apparent corrosion of the stainless

steel on specimens buried at Sites A, C, and E. The shield of the specimen

buried for five years at Site C was perforated due to corrosion at the

un jacketed ring.

Of the specimens buried at Site G corrosion of the stainless steel was

noted at both jacketed and un jacketed areas on specimens exposed for four

and five years.

Degradation of varied degree of the vapor deposited aluminum was noted

on all specimens. The coating was ELD or near ELD at jacketed and/or

un jacketed areas after exposure for two years at Sites A, E, and G, and five

years at Site C.

System 60 . This system consisted of a 3-mil (0.08 mm) Type 304 stainless steel with 2-mil (0.05 mm) vapor deposited aluminum coating on the

outer and core sides of the shield.

Specimens of this system were buried at Sites A, C, E, and G only.

There was no apparent corrosion of the stainless steel on any of the

specimens buried for up to five years at these sites.
18

Degradation of varying degree with respect to the vapor deposited

aluminum coating on the outer and inner surfaces of the stainless steel was

noted on all specimens buried at these sites. The coating on the inner

surface was ELD at jacketed areas on the specimens buried for one year at

Sites A and G, five years at Site C, and four years at Site E. Degradation

of the coating on the outer surface was negligible on specimens buried for

up to five years at Sites A, C, and E. However, the coating on the outer

surface was ELD on the specimen buried for three years at Site G.

System 61 . This system is the same as System 60 except that the system

was coupled to copper.

Specimens of this system were buried at Sites A, C, E, and G only.

There was no apparent corrosion of the stainless steel on any of the

specimens exposed at these sites for up to five years.

Degradation of the vapor deposited aluminum coating was observed on all

specimens buried at these sites. The coating on the inner surface of the

specimens was ELD at jacketed and/or unjacketed areas on specimens buried

for two years at Site A and one year at Sites C, E, and G. Degradation of

the coating on the outer surface was negligible on all specimens buried at

Sites C, E, and G for up to five years. The performance of this coating

was poor to very poor at jacketed and/or un jacketed areas of the specimens

buried for up to three years at Site A. Degradation of the coating was

negligible on specimens exposed at this site for four and five years.

System 62 . This system consisted of a 50-pair, 22-gauge air core

cable having an 8-mil (0.20 mm) aluminum shield with a copolymer coating

on both sides of the shield. There was no window or ring on specimens of

this system. The conductors were removed from the cable leaving a hollow

shel 1

.
The performance of this system was excellent after exposure for five

years at Sites A and C and four years at Site B. Degradation was not appreciable for specimens exposed at Site D for up to five years or Site E for

up to four years. After exposure for two and four years at Site G, the

shield was perforated due to localized pitting corrosion while companion

specimens exposed for three years and five years were unaffected by corrosion.

System 63 . This system consisted of a 16-pair, 22-gauge cable having

an 8-mil (0.20 mm) uncorrugated aluminum alloy shield bonded both sides to

a polyolefin polymer. The shield was bonded to the jacket. There was no

window or ring on specimens of this system. The conductors were removed

from the cable leaving a hollow shell.

No corrosion was observed on specimens buried for five years at Sites A,

B, C, or D, and four years at Site E. The shields of specimens buried for one,

two, and five years at Site G had perforated due to corrosion while companion

specimens buried for one and three years were unaffected by corrosion.

System 64 . This system consisted of a 25-pair, 18-gauge cable having

an 8-mil (0.20 mm) uncorrugated aluminum alloy shield bonded both sides to

a 2-mil (0.05 mm) polyolefin polymer. The shield was bonded to the jacket.

Specimens buried for up to five years at Sites A and D and four years at

Sites B and E were unaffected by corrosion. Only four specimens were buried

at Site B due to a lack of sufficient material to allow for five- and six-year

recovery of specimens after exposure. Pitting corrosion which resulted in

perforation of the shield was noted on one specimen buried for four years

at Site C and on specimens buried for four and five years at Site G. Other

specimens exposed at these sites were unaffected by corrosion.
System 65 . This system consisted of a 25-pair, 24-gauge cable having

an 8-mil (0.20 mm) uncorrugated aluminum alloy shield bonded both sides to

a polyolefin polymer. The shield was bonded to the jacket.

There was no apparent corrosion on specimens of this system after

burial for up to five years at Sites A, B, C, 0, and G, and four years at

Site E.

System 66 . This system is the same as System 65 except that the

shield was coupled to copper.

Specimens of this system were unaffected by corrosion after exposure

for up to five years at Sites A, B, C, and D, and four years at Site E.

System 67 . This system consisted of a 4-mil (0.10 mm) aluminum foil

[3 3/4 in. x 8 in. (9.52 cm x 20.32 cm)] coated both sides with a 6-mil

(0.15 mm) ethylene acrylic acid copolymer.

There was no apparent degradation on specimens of this system after

exposure for three years at Sites A, B, and D, and two years at Site C.

(Specimens buried for two years at Sites B and D and three years at Site C

were not recovered.

)

System 68 . This system consisted of a 4-mil (0.10 mm) aluminum foil

[3 3/4 in. x 8 in. (9.52 cm x 20.32 cm)] coated both sides with a 6-mil

(0.15 mm) polyester film.

Specimens of this system were unaffected by corrosion after exposure

for three years at Sites A, B, and D, and two years at Site C. (The specimen

buried for three years at Site C was not recovered.)

System 69 . This system consisted of a 4-mil (0.10 mm) aluminum foil

[1 1/2 in. x 12 in. (3.81 cm x 30.48 cm)] coated both sides with a 5.5 mil

(0.14 mm) polyester film.
Corrosion of specimens of this system was nil for materials buried for

up to three years at Site A, and two years at Sites B, C, and D. (Specimens

buried for three years at Sites B and C, and one and three years at Site D

were not recovered.

)

System 70 . This system consisted of a 25-pair, 24-gauge cable having

a 6-mil (0.15 mm) corrugated copper alloy outer shield (nominal chemical

composition: 97.5 percent Cu, 2.5 percent Fe, 0.02 percent P) and an inner

shield of 4-mil (0.10 mm) aluminum alloy coated on both sides with a 5.5-mil

(0.14 mm) polyester film. The outer shield was bonded to the jacket. This

was a filled cable having a clear flooding compound.

Corrosion was nil for specimens buried up to two years at Site A and

three years at Sites B, C, and D. Severe corrosion was noted on the specimen

buried for three years at Site A. More than twenty- five percent of the

metal shield was dissipated due to corrosion.

The filling compound was still tacky, except at corroded areas.

Systems 71 and 72 were buried plant housings and are not included in

this report.

System 73 . This system consisted of a 25-pair, 22-gauge cable having

a 6-mil (0.15 mm) corrugated black plate steel outer shield and an 8-mil

(0.20 mm) corrugated aluminum alloy inner shield coated both sides with a

2-mil (0.05 mm) ethylene acrylic acid copolymer. This was a filled cable

having a clear flooding compound over the core and inner shield and another

type of clear flooding compound over the outer shield.

In general, the inner and outer shields of specimens exposed for one year

at all sites were unaffected by corrosion. Corrosion of the inner shield was

severe at the un jacketed window and ring areas on the specimen buried at
Site B for two years. The outer shields of the specimens buried at Sites

A, D, and G for two years, Site B for one year, and Site C for one and two

years were severely corroded at unjacketed window and/or ring areas. The

specimen buried at Site B was ELD at these areas.

System 74 . This system was the same as System 73 except that the

shields were coupled to copper.

With a few exceptions, corrosion of the inner shields on specimens

buried for up to two years at all of the sites was nil or superficial. The

inner shield of the specimen buried for two years at Site C was ELD at the

un jacketed window while that of the specimen buried for two years at Site G

was ELD at all areas examined.

The filling compound was still tacky except at corroded areas.

System 75 . This system consisted of a 25-pair, 22-gauge cable having

a 6-mil (0.15 mm) corrugated steel outer shield, coated both sides with a

2-mil (0.05 mm) ethylene acrylic acid copolymer and an 8-mil (0.20 mm)

corrugated aluminum alloy inner shield, coated both sides with a 2-mil

(0.05 mm) ethylene acrylic acid copolymer. This was a filled cable having

a clear flooding compound over the core and inner shield and another type

of clear flooding compound over the outer shield.

The inner shield on specimens exposed for up to two years at all sites

was unaffected by corrosion. The outer shield on specimens buried at Sites

B and D for two years, and Site E for one year was also unaffected by

corrosion. Corrosion of the outer shield was observed at the window and

ring areas on specimens buried at Sites A, C, and G for two years. Corrosion

was more severe on the specimen buried at Site G where the exposed window

was near ELD. Corrosion of the outer shield was also observed at jacketed

areas on the specimens buried at Sites C and G.
The filling compounds were tacky except at areas on the shields where

corrosion was observed.

System 76 . Same as System 75 except that the shields were coupled to

copper. Coupling the shields to copper accelerated the corrosion of the

outer shield in all of the soils in which the specimens were exposed. No

degradation was observed on the inner shield of any of the specimens buried

for up to two years. With one exception the outer shield on all specimens

was corroded in varying degrees at un jacketed areas. Corrosion at these

areas was most severe on specimens buried at Sites C and G. The outer shield

of the specimen buried for two years at Site G was ELD at the exposed

(unjacketed) window and ring. The outer shield of the specimen buried for

one year at Site A was unaffected by corrosion.

The filling compounds were still tacky except at corroded areas.

System 77 . This system consisted of a 25-pair, 22-gauge cable having

a 6-mil (0.20 mm) corrugated steel outer shield and an 8-mil (0.20 mm)

corrugated aluminum alloy inner shield coated both sides with a 2-mil

(0.05 mm) ethylene acrylic acid copolymer. This was a filled cable having

a clear flooding compound over the core and inner shield and another type

of clear flooding compound over the outer shield.

The inner shield of specimens of this system were unaffected by corrosion

after burial for up to two years in the soil environments. There was no

degradation of the outer shield of specimens buried for one year at Sites

A, B, and C. After exposure for two years, corrosion of the outer shield

was nil or superficial at jacketed areas for all specimens. Corrosion of

the outer shield was observed at the unjacketed window and ring areas on

l all of the specimens that had been buried for two years. The specimen
buried at Site G was ELD at these areas. Localized pitting corrosion was

noted at these areas on specimens buried at Sites A, B, C, and D for two

years, and Site E for one year.

The filling was still tacky except at areas on the shields where

corrosion was observed.

System 78 . Same as System 77 except that the shields were coupled to

copper.

Coupling the shields to copper accelerated corrosion of the outer

shield in all of the soils and the inner shield at Sites C and G. The

inner shields of specimens buried for two years at Sites B and D were

unaffected by corrosion. Corrosion of the inner shield on specimens buried

at Sites C and E occurred at the window and/or ring areas. Of the specimens

buried at Site G, the inner shield was ELD or near ELD at window and ring

areas and severely corroded at jacketed areas. In general, severe corrosion

was observed on the outer shield at the window and ring areas on all specimens

of this system. Of the systems buried for two years, the outer shield of

those exposed at Sites B, C, and G was at or near ELD at the un jacketed

window and ring areas. Corrosion of the outer shield was severe at the

window and ring areas on specimens of this system buried for two years at

Sites A and D and one year at Site E.

The filling compound was still tacky except at corroded areas.

System 79 . This system consisted of a 25-pair, 22-gauge cable having

a 6-mil (0.15 mm) corrugated steel outer shield and an 8-mil (0.20 mm) corrugated aluminum alloy inner shield. This was a filled cable having a clear

flooding compound over the core and inner shield and another type of clear

flooding compound over the outer shield.
24

Except for the specimens buried at Site G, there was no degradation of

the inner shield on any of the specimens buried for up to two years in the

25

soils. Severe corrosion was noted on the inner shield at window and ring

areas of the specimens buried for one and two years at Site G. In general,

corrosion of the outer shield occurred at or adjacent to un jacketed window

and ring areas. The specimen buried at Site G was near ELD at these areas.

Superficial degradation of the outer shield was noted at jacketed areas on

the specimen buried for two years at Site B, while localized pitting corrosion

was noted on companion specimens buried for one year at Site E and two

years at Site G.

The filling compounds were tacky at all uncorroded areas of the shields.

System 80 . Same as System 79 except that the shields were coupled to

copper.

Coupling specimens of this system to coppper accelerated the corrosion

of the shields. With a few exceptions there was little or no corrosion on

either shield at jacketed areas of specimens buried at Sites A, B, C, D,

and E. The inner shield was perforated due to corrosion at the jacketed

ring and/or window areas on specimens buried for two years at Sites A and

C. The outer shield was perforated at unjacketed areas of the window

and/or ring on specimens buried for up to two years at all sites. After

exposure for one year at Site G the unjacketed window and ring areas were

at or near ELD due to corrosion. The specimen buried at this site for two

years was ELD due to severe degradation at all areas examined and was

considered destroyed.

The filling compounds were still tacky at all uncorroded areas of the

shields.
System 81 . This system consisted of a 25-pair, 22gauge cable having a

6-mil (0.15 mm) corrugated steel outer shield coated both sides with 2-mil

(0.05 mm) ethylene acrylic acid copolymer and an 8-mil (0.20 mm) corrugated

aluminum alloy inner shield coated both sides with 2-mil (0.05 mm) ethylene

acrylic acid copolymer. This was a filled cable with amorphous polypropylene

applied over the core, inner shield, and outer shield.

There was no corrosion of the inner shield on specimens of this system

buried for up to two years at the six soil test sites. Corrosion of the

outer shield in varying degrees was noted at un jacketed window and ring

areas of specimens buried for two years at Sites B, D, and G, and one year

at Sites C and E.

The filling compound was still tacky except at corroded areas.

System 82 . Same as System 81 except that the shields were coupled to

copper.

Coupling specimens of this system to copper accelerated corrosion of

the outer steel shield in all of the soils at window and ring areas. The

inner aluminum shield was unaffected by corrosion at jacketed areas, but

was severely corroded at unjacketed window and/or ring areas of the specimens

buried for two years at Sites A and C. The inner shields of these specimens

were ELD or near ELD. The specimen buried for two years at Site G was

severely corroded at all areas examined and was considered destroyed.

The filling compound was semi -tacky to dry for all specimens.

System 83 . This system consisted of a 25-pair, 22-gauge cable having

a 6-mil (0.15 mm) corrugated steel outer shield coated both sides with

2-mil (0.05 mm) ethylene acrylic acid copolymer and an 8-mil (0.20 mm)

corrugated aluminum alloy inner shield coated both sides with ethylene
acrylic acid copolymer. This was a filled cable with amorphous polypropylene applied over the core, inner shield, and outer shield.

With a few exceptions, specimens of this system were unaffected by

corrosion. The outer shield was perforated at the unjacketed ring on one

specimen exposed for two years at Site C, while both shields of companion

specimens buried for one and two years at Site G were perforated due to

corrosion at unjacketed window and ring areas.

The filling compound was semi tacky to dry for all specimens.

System 84 . Same as System 83 except that the shields were coupled to

copper.

Coupling specimens of this system to copper accelerated the corrosion

of the outer corrugated steel shield of specimens buried in five of the six

soils. There was no degradation of either shield on the specimen buried

for two years at Site A. Corrosion of the outer shield on specimens buried

for up to two years was in general observed at unjacketed window and ring

areas. One specimen exposed for two years at Site G was ELD at both areas

while specimens exposed for two years at Sites B, C, and D and one year at

Site D were perforated due to corrosion at one or both of these areas.

The filling compound was semi tacky to dry for all specimens.

System 85 . This consisted of a 25-pair, 22-gauge cable having a 6-mil

(0.15 mm) corrugated steel outer shield and an 8-mil (0.20 mm) corrugated

aluminum alloy shield. This was a filled cable with amorphous polypropylene

applied over core, inner shield, and outer shield.

With the exception of specimens buried for one and two years at Site

G, corrosion of the inner aluminum shield was nil. The inner shield of the

specimen buried at this site for one year was near ELD at the unjacketed
ring area. A companion specimen buried for two years at this site was

severely corroded at all areas examined and was considered destroyed.

Corrosion of the outer corrugated steel shield of specimens buried for up

to two years at Site A was nil or negligible. The outer corrugated steel

shield of specimens buried at Sites B, C, and D for two years was perforated due to corrosion at unjacketed window and ring areas, while corrosion

of the outer shield of the specimen buried for one year at Site E was most

severe at the un jacketed ring area only.

The filling compound was semi tacky to dry for all specimens.

System 86 . Same as System 85 except that the shields were coupled to

copper.

Coupling specimens of this system to copper accelerated corrosion of

the shields particularly at unjacketed areas. The inner corrugated aluminum

shield of the specimen buried for two years at Site C was ELD at all areas

examined, while the outer corrugated steel shield was relatively unaffected

by corrosion at jacketed areas. Severe corrosion of both shields was noted

on specimens buried for up to two years at Site G. The inner aluminum

shield of the specimen buried for one year at this site was perforated due

to corrosion at all areas examined, while corrosion of the outer steel

shield at jacketed areas was negligible. At unjacketed window and ring

areas of this specimen the outer shield was ELD. Both shields of a companion

specimen buried for two years at this site were ELD at all areas examined;

this specimen was considered destroyed. Of the specimens buried in the

other four soils, the outer shields of all were perforated due to corrosion

at un jacketed window and ring areas.

The filling compound was semi tacky to dry for all specimens.
System 87 . This system consisted of a 25-pair, 22-gauge cable having

a 6-mil (0.15 mm) corrugated black plate steel outer shield and an 8-mil

(0.20 mm) corrugated aluminum alloy inner shield coated both sides with

2-mil (0.05 mm) ethylene acrylic acid copolymer. This was a filled cable

with amorphous polypropylene applied over core, inner shield, and outer

shield.

There was no degradation of the corrugated aluminum alloy inner shield

of specimens buried for up to two years in five of the six soils. The

inner shield of the specimen buried for two years at Site G was perforated

by corrosion at all areas examined. However, the inner shield was electrically

continuous at these areas. With a few exceptions, corrosion of the corrugated

black plate steel outer shield was negligible at jacketed areas. The

jacketed outer shield on two specimens of this system, one exposed for two

years at Site D and one exposed for one year at Site E, were perforated due

to pitting corrosion at localized areas remote from the window and ring.

The outer shield was ELD at the un jacketed window and ring of the specimen

buried for two years at Site G, while these areas on the outer shield were

perforated due to localized pitting corrosion on specimens buried in the

other five soils.

The filling compound was semi tacky to dry for all specimens.

System 88 . Same as System 86 except that the shield were coupled to

copper.

Coupling specimens of this system to copper accelerated corrosion of

the black plate steel outer shield at window and ring areas in all of the

soils in which the specimens were exposed. The performance of the outer

shields at these unjacketed areas was in general fair to very poor for
specimens buried in the six soils. Corrosion of the corrugated aluminum

inner shield at jacketed areas was nil for specimens buried for up to two

years in four of the six soils. Severe corrosion was noted at the area

adjacent to the unjacketed window of the specimen buried at Site C for two

years. Of the specimens buried at Site G for two years, both shields were

ELD at all areas rated. This specimen was considered destroyed.

The filling compound was semi tacky to dry for all specimens.

System 89 . This system consisted of a 100-pair, 22-gauge semi -conducting

cable having a 5-mil (0.13 mm) corrugated copper alloy shield and a low

density polyethylene jacket.

Corrosion of specimens of this system was nil or negligible in all of

the soils after exposure for one year.

System 90 . Same as System 89 except that the shield was coupled to

copper.

Coupling specimens of this system to copper had no effect on the

corrosion behavior of the copper alloy shield.

System 91 . This system consisted of a 3-mil (0.09 mm) corrugated 1006

low carbon steel outer shield bonded to a 3-mil (0.08 mm) corrugated 4022

aluminum alloy inner shield.

There was no appreciable corrosion of either shield at jacketed areas

of specimens buried for one year at Sites B, C, and 0. The shields of the

specimens buried at Sites B and C were perforated due to corrosion at

unjacketed window and/or ring areas. Of the specimens exposed at Sites A

and G, both shields were ELD at all areas examined and these specimens were

considered to be destroyed.
31

System 92 . Same as System 91 except that the shields were coupled to

copper.

Specimens of this system were exposed at Sites A, B, and G only.

Coupling this system to copper accelerated corrosion of both shields. The

shields of specimens buried for one year in these three soils were ELD at

all areas examined and were considered to be destroyed.

System 93 . This system consisted of a 3-mil (0.08 mm) corrugated 1006

low carbon steel inner shield bonded to a 3-mil (0.08 mm) corrugated 4022 aluminum

alloy outer shield.

Specimens of this system were exposed at Sites A, B, C,

0, and E only. With one exception there was no appreciable degradation of

the outer aluminum alloy shield after exposure for one year at these sites.

The outer shield of the specimen exposed for one year at Site A was perforated

due to corrosion at all areas examined. However, this shield was still

electrically continuous. The inner low carbon steel shield was ELD at all

areas rated on all of the specimens buried for one year at Sites B, C, and D.

The inner shield of the specimen buried at Site A for one year was ELD at

jacketed and unjacketed window and ring areas. At other jacketed areas on

this specimen, the inner shield was severely corroded but was electrically

continuous.

System 94 . Same as System 93 except that the shields were coupled

to copper. Specimens of this system were exposed at Sites A and B only.

Coupling specimens of this system to copper accelerated corrosion of both

shields. Both the inner and outer shields of the specimens buried for one

year at these sites were ELD at all areas examined. These specimens were

considered to be destroyed.
32

SUMMARY AND DISCUSSION

The data presented give the performance of various cable systems after

exposure for up to six years in different soil environments. Fifty-two (52)

different shielding systems (using metal or plastic coated metals) were

investigated under some very adverse conditions.

With a few exceptions, direct burial telephone cable specimens containing

the various metallic shielding protective systems were fabricated with portions

of the outer jackets damaged in order to simulate that which could occur in

actual field installations. In addition some of the systems were electrically

coupled to copper strips, thus creating a galvanic cell between the copper

and the shield materials which were other than copper. This was done to

simulate field conditions where the shield may be coupled to existing cable

systems having copper shields or to copper ground rods.

Six soil environments were employed which have chemical and physical

properties representative of a wide range of soils that may be encountered

in the United States in actual field installations. Some are moderately

corrosive and some are very corrosive toward ferrous and other metals or alloys.

The data show that of the cable specimens buried for up to six years,

few were resistant to corrosion in all of the soils in which they were

exposed.
After exposure for six years in clay, Lakewood sand, and coastal sand

environments, and five years in alkaline soil and in tidal marsh, specimens

of Systems 53 and 54 were in general unaffected by corrosion. Specimens of

these systems were not exposed in Hagerstown loam. System 53 was a filled

cable fabricated with a 0.20 mm, 1100 aluminum alloy shield adhesive bonded

on both sides with 0.04 mm polyethylene, while System 54 was the same except

that the shield was coupled to copper.

Corrosion was nil or superficial for specimens of Systems 41, 43, and

45 buried for six years in alkaline soil. However, their performance in the

acid clay and tidal marsh was very poor. Specimens of these systems were

not buried in Hagerstown loam, Lakewood sand, or coastal sand. System 41 was

a filled cable fabricated with a 0.20 mm uncorrugated 1100 aluminum alloy

shield, System 43 was a cable fabricated with a 0.20 mm corrugated 1100

aluminum alloy outer and inner shield with a polyethylene jacket bonded to

the innder sides of both shields, while System 45 was a cable fabricated

with an uncorrugated 1100 aluminum alloy shield coated with resin on both

sides.

Specimens of Systems 47, 48, 51, and 52 were relatively unaffected by

corrosion after exposure for up to six years in Hagerstown loam. The

performance of these systems in the other five soil environments was in

general fair to very poor, particularly with respect to the inner shield.

System 46 was a cable fabricated with a 0.08 mm corrugated Type 304 stainless

steel outer shield bonded with a polyurethane adhesive to a 0.15 mm corrugated

aluminum alloy inner shield which was vinyl coated on both sides. Systems

49 and 51 were the same as System 47 except that the thickness of the inner

shield of System 47 was 0.10 mm while for System 51 the adhesive used to

bond the outer and inner shields was an epoxy based compound.
After exposure for five years in alkaline soil, clay, and Lakewood

sand, and four to five years in Hagerstown loam, there was little or no

degradation due to corrosion of specimens of Systems 62, 63, 64, 65, and

66. Similarly there was no degradation of the shield of specimens of

System 65 after exposure for up to five years in tidal marsh. The performance

for specimens of Systems 62, 63, and 64 exposed in tidal marsh was in general

fair. Specimens of System 66 were not buried in this soil. System 62 was

an air core cable fabricated with a 0.20 mm aluminum shield coated on both

sides with a copolymer coating. Systems 63 and 65 were cables fabricated

with a 0.20 mm uncorrugated aluminum alloy shield bonded both sides to a

polyolefin polymer. A different material was used to bond the copolymer

to the metallic shields on each of these systems. System 64 was a cable

fabricated with a 0.20 mm aluminum alloy shield bonded both sides with a

0.05 mm polyolefin polymer. System 66 was the same as System 65 except that

the shield was coupled to copper. In addition, the shields of Systems 63, 64,

65, and 66 were bonded to the jacket.

Specimens of Systems 67, 68, and 69 buried for three years in alkaline

soil, Hagerstown loam, clay, and Lakewood sand were unaffected by corrosion.

These systems were not exposed in coastal sand or tidal marsh. Specimens

of these systems were fabricated using 0.10 mm thick aluminum foil. The

foil of System 67 was coated both sides with a 0.15 mm ethylene acrylic

acid copolymer while the foil of System 68 was coated both sides with a

0.15 mm polyester film and the foil of System 69 was coated both sides

with a 0.14 mm polyester film.

Of the specimens exposed for two years in alkaline soil, Hagerstown

loam, clay, and Lakewood sand, and one year in coastal sand, Systems 75 and

83 were in general unaffected by corrosion. The performance with respect
to corrosion of System 84 was excellent after exposure for two years in

alkaline soil and Hagerstown loam and fair after exposure for two years in

clay, Lakewood sand, and coastal sand. Specimens of these systems buried in

the tidal marsh were severely corroded. System 75 was a filled cable

fabricated with a 0.15 mm corrugated steel outer shield coated both sides

with a 0.05 mm ethylene acrylic acid copolymer and a 0.20 mm corrugated

aluminum alloy inner shield coated both sides with an ethylene acrylic

acid copolymer. System 83 was a filled cable fabricated with a 0.15 mm

corrugated steel outer shield, coated both sides with 0.05 mm ethylene

acrylic acid copolymer and an 0.20 mm corrugated aluminum alloy inner

shield coated both sides with ethylene acrylic acid copolymer. System 84

was the same as System 85 except that the shield was coupled to copper.

The performance of Systems 76 and 77 after exposure for two years was

good in alkaline soil and coastal sand, fair in Hagerstown loam, and poor

to very poor in clay and tidal marsh. After exposure for one year in coastal

sand the performance for System 77 was good while that for System 76 was

poor. System 76 was the same as System 75 except that the shield was coupled

to copper. System 77 was a filled cable fabricated with a 0.20 mm corrugated

steel outer shield and a 0.20 mm corrugated aluminum inner shield coated

both sides with 0.05 mm ethylene acrylic acid copolymer. System 79 was in

general unaffected by corrosion after exposure for two years in the alkaline

soil, but its performance with respect to corrosion was fair in Hagerstown

loam and Lakewood sand. This system was a filled cable fabricated with a

0.15 mm corrugated steel outer shield and a 0.20 mm corrugated aluminum

alloy inner shield.
36

After exposure for one year, specimens of Systems 89 and 90 were

unaffected by corrosion in five of the six soils. The corrosion behavior

for specimens buried at Site E could not be determined due to topographical

changes at the site which resulted in the loss of location markers. The

performance with respect to corrosion of System 91 after exposure for one

year was fair at Site A, good at Site B, and very poor at Site C. Specimens

of this system were not exposed in the other soils. System 89 was a semiconducting cable having a 0.13 mm copper alloy shield and a low density

polyethylene jacket. System 90 was the same except that the shield was

coupled to copper. System 91 was a cable fabricated with a 0.08 mm

corrugated 1006 low carbon steel outer shield bonded to a 0.08 mm 4022

aluminum alloy inner shield.

The following should not be considered for use because of the relatively

poor performance in one or more of the less aggressive soils: Systems No. 55,

58, 60, 61, 73, 77, 79, 81, 85, 87, 91, and 93.

When Systems No. 42, 44, 46, 48, 50, 52, 57, 59, 74, 78, 80, 82, 84,

86, 88, 92, and 94 were coupled to copper, their performance was poor to

very poor in one or more of the soils. For most of the materials studied

in this investigation, the copper strip coupled to the shield caused an

appreciable acceleration of corrosion to the shield over that observed when

the same material was not coupled to copper. The copper behaved as the

cathode in a galvanic cell where the dissimilar metal shield was the anode.

The result was dissipation of the shield by sacrificial corrosion in addition

to the normal corrosion occurring in the particular soil environment.

Some exceptions to the above were noted where some specimens fabricated

with stainless steel shields were coupled to copper, i.e., Systems No. 48,

50, 57, and 59. For these specimens the copper would be anodic to the
stainless steel outer shield and cathodic to the inner aluminum shield. It

was noted that there was little or no degradation of the copper strips

buried in any of the soils; however, some green patina was observed at

areas on all of the copper strips.
PREPARATION OF SPECIMENS

FOR CABLE EXPOSURE TESTS

SPECIMEN DIMENSIONS

Z

SPECIMEN TYPE I

14

'

rtnsmc

10

SPECIMEN TYPE 2 CORE AND INNER JACKET

i

T

1.5’H

XSHIELD OVERLAP

^CORRUGATED SHIELD

OUTER JACKET

PREPARATION OF SPECIMEN TYPE I —>I.75T<—

1 -2

"

SEAL BOTH ENDS WITH SEALING

COMPOUND AND VINYL TAPE

0.5" RING AROUND

'CIRCUMFERENCE OF

CABLE

m .X 55 $

V NBS IDENTIFICATION TAG

2 x 0.5 WINDOW

AT SHIELD OVERLAP

Figure 1 Preparation of specimens for cable exposure tests
Tables

Table 1

Table 2

Table 3

Table 4

Table 5

Table 6

Table 7

Table 8

Table 9

Description of Various Systems Included in the Soil Corrosion

Study of Telephone Cable Shielding Materials

Properties of the Soils at the Test Sites

Rating Code for the Corrosion Evaluation of Shields in Cable

Specimens

Performance of Shields in Cable Specimens Buried for Up to Six

Years in Sagemoor Sandy Loam (Site A)

Performance of Shields in Cable Specimens Buried for Up to Six

Years in Hagerstown Loam (Site B)

Performance of Shields in Cable Specimens Buried for Up to Six

Years in Clay Soil (Site C)

Performance of Shields in Cable Specimens Buried for Up to Six

Years in Lakewood Sand (Site D)

Performance of Shields in Cable Specimens Buried for Up to Six

Years in Coastal Sand (Site E)

Performance of Shields in Cable Specimens Buried for Up to Six

Years in Tidal Marsh (Site G)
Table 1. Description of Various Systems Included in the Soil Corrosion Study

of Telephone Cable Shielding Materials.

System 1 Description

41 25-pair, 22-gauge cable having an 8-mil (0.20 mm) uncorrugated

1100 aluminum alloy shield. This was a filled cable (polyethylene, 15 percent petroleum jelly, 85 percent by volume in

conductor interstices and on both sides of the shield).

42 Same as System 41, except that the shield was coupled to copper.

43 100-pair, 19-gauge cable having an 8-mil (0.20 mm) corrugated

1100 aluminum alloy inner and outer shield with a polyethylene

jacket bonded to the inner sides of both shields.

44 Same as System 43, except that the shield was coupled to copper.

45 100-pair, 22-gauge cable having an 8-mil (0.20 mm) uncorrugated

1100 aluminum alloy shield coated with resin on both sides.

Shield was bonded to the jacket.

46 Same as System 45, except that the shield was coupled to copper.

47 3-mil (0.08 mm) corrugated Type 304 stainless outer shield

bonded with a polyurethane adhesive to a 6-mil (0.15 mm) corrugated

aluminum alloy inner shield which was vinyl coated on both sides.

48 Same as System 47, except that the system was coupled to copper.

49 3-mil (0.08 mm) corrugated Type 304 stainless steel outer shield

bonded to a 4-mil (0.10 mm) corrugated 1100 aluminum alloy inner

shield which was vinyl coated on both sides.

50 Same as System 49, except that the system was coupled to copper.

51 Same as System 47, except that the adhesive used to bond the outer

and inner shields was an epoxy base compound.

52 Same as System 51, except that the system was coupled to copper.

53 25-pair, 19-gauge filled cable having an 8-mil (0.20 mm) 1100

aluminum alloy shield adhesive bonded on both sides with 1.5-mil

(0.04 mm) polyethylene.

54 Same as System 53, except that the system was coupled to copper.

55 8-mil (0.20 mm) 1100 aluminum alloy foil [4 in. x 9 in. (10.16 cm x 22.86 cm)] bonded both sides with 1.5-mil (0.04 mm) polyethylene.

56 3-mil (0.08 mm) Type 430 stainless steel outer shield bonded to a 3-mil (0.08 mm) 1100 aluminum alloy inner shield with a clear

flooding compound on the core side.
40 41

Table 1 (continued)

System 1 Description

57 Same as System 56, except that the system was coupled to copper.

58 3-mil (0.08 mm) Type 304 stainless steel with 4-mil (0.10 mm) vapor

deposited aluminum on the outer surface.

59 Same as System 58, except that the shield was coupled to copper.

60 3-mil (0.08 mm) Type 304 stainless steel with 2-mil (0.05 mm) vapor

deposited aluminum on the outer and core sides of the shield.

61 Same as System 60, except that the shield was coupled to copper.

62 50-pair, 22-gauge air core cable having an 8-mil (0.20 mm)

aluminum alloy shield with a copolymer coating on both sides of

the shield. Cable core was removed.

63 16-oair, 22-gauge cable having an 8-mil (0.20 mm) uncorrugated

aluminum alloy shield bonded both sides to a polyolefin polymer.

Shield was bonded to the jacket.

64 25-pair; 18-gauge cable having an 8-mil (0.20 mm) uncorrugated

aluminum alloy shield bonded both sides to a 2-mil (0.05 mm)

polyolefin polymer. Shield was bonded to the jacket.

65 25-pair, 24-gauge cable having an 8-mil (0.20 mm) uncorrugated

aluminum alloy shield bonded both sides to a polyolefin polymer.

Shield was bonded to the jacket.

66 Same as System 65, except that the shield was coupled to copper.

67 4-mil (0.10 mm) aluminum foil [3 3/4 in. x 8 in. (9.52 cm x 20.32 cm)]

coated both sides with a 6-mil (0.15 mm) ethylene acrylic acid

copolymer.

68 4-mil (0.10 mm) aluminum foil [3 3/4 in x 8 in. (9.52 cm x 20.32 cm)]

coated both sides with a 6-mil (0.15 mm) polyester film.

69 4-mil (0.10 mm) aluminum foil [1 1/2 in. x 12 in. (3.81 cm x 30.48 cm)]

coated both sides with a 5.5 mil (0.14 mm) polyester film.

70 25-pair, 24-gauge cable having a 6-mil (0.15 mm) corrugated copper

alloy outer shield (nominal chemical composition: 97.5 percent Cu,

2.5 percent Fe, 0.02 percent P) and an inner shield of 4-mil

(0.10 mm) aluminum alloy coated on both sides with a 5.5-mil

(0.14 mm) polyester film. Outer shield was bonded to the jacket.

This was a filled cable having a clear flooding compound.
System1

Table 1 (continued)

Description

73 25-pair, 22-gauge cable having a 6-mil (0.15 mm) corrugated black

plate steel outer shield and an 8-mil (0.20 mm) corrugated aluminum alloy inner shield coated both sides with a 2-mil (0.05 mm)

ethylene acrylic acid copolymer. This was a filled cable having

a clear flooding compound over the core and inner shield and

another type of clear flooding compound over the outer shield.

74 Same as System 73, except that the shields were coupled to copper.

75 25-pair, 22-gauge cable having a 6-mil (0.15 mm) corrugated steel

outer shield, coated both sides with a 2-mil (0.05 mm) ethylene

acrylic acid copolymer and an 8-mil (0.20 mm) corrugated aluminum

alloy inner shield, coated both sides with a 2-mil (0.05 mm)

ethylene acrylic acid copolymer. This was a filled cable having

a clear flooding compound over the core and inner shield and

another type of clear flooding compound over the outer shield.

76 Same as System 75, except that the shields were coupled to copper.

77 25-pair, 22-gauge cable having a 6-mil (0.20 mm) corrugated steel

outer shield and an 8-mil (0.20 mm) corrugated aluminun alloy

inner shield coated both sides with a 2-mil (0.05 mm) ethylene

acrylic acid copolymer. This was a filled cable having a clear

flooding compound over the core and inner shield and another

type of clear flooding compound over the outer shield.

78 Same as System 77, except that the shields were coupled to copper.

79 25-pair, 22-gauge cable having a 6-mil (0.15 mm) corrugated steel

outer shield and an 8-mil (0.20 mm) corrugated aluminum alloy

inner shield. This was a filled cable having a clear flooding

compound over the core and inner shield and another type of

clear flooding compound over the outer shield.

80 Same as System 79, except that the shields were coupled to copper.

81 25-pair, 22-gauge cable having a 6-mil (0.15 mm) corrugated steel

outer shield coated both sides with 2-mil (0.05 mm) ethylene

acrylic acid copolymer and an 8-mil (0.20 mm) corrugated aluminum

alloy inner shield coated both sides with 2-mil (0.05 mm) ethylene

acrylic acid copolymer. This was a filled cable with amorphous

polypropylene applied over the core, inner shield, and outer shield.

82 Same as System 81, except that the shields were coupled to copper.

83 25-pair, 22-gauge cable having a 6-mil (0.15 mm) corrugated steel

outer shield coated both sides with 2-mil (0.05 mm) ethylene

acrylic acid copolymer and an 8-mil (0.20 mm) corrugated aluminum

alloy inner shield coated both sides with ethylene acrylic acid

copolymer. This was a filled cable with amorphous polypropylene

applied over the core, inner shield, and outer shield.
Table 1 (continued)

84 Same as System 83, except that the shields were coupled to copper.

85 25-pair, 22-gauge cable having a 6-mil (0.15 mm) corrugated steel

outer shield and an 8-mil (0.20 mm) corrugated aluminum alloy

shield. This was a filled cable with amorphous polypropylene

applied over core, inner shield, and outer shield.

86 Same as System 85, except that the shields were coupled to copper.

87 25-pair, 22-gauge cable having a 6-mil (0.15 mm) corrugated black

plate steel outer shield and an 8-mil (0.20 mm) corrugated aluminum alloy inner shield coated both sides with 2-mil (0.05 mm)

ethylene acrylic acid copolymer. This was a filled cable with

amorphous polypropylene applied over core, inner shield, and

outer shield.

88 Same as System 87, except that the shields were coupled to copper.

89 100-pair, 22-gauge semi-conducting cable having a 5-mil (0.13 mm)

corrugated copper alloy shield and a low density polyethylene

jacket.

90 Same as System 89, except that the shield was coupled to copper.

91 3-mil (0.08 mm) corrugated 1006 low carbon steel outer shield

bonded to a 3-mil (0.08 mm) corrugated 4022 aluminum alloy inner

shield.

92 Same as System 91, except that the shields were coupled to copper.

93 3-mil (0.08 mm) corrugated 1006 low carbon steel inner shield

bonded to a 3-mil (0.08 mm) corrugated 4022 aluminum alloy outer

shield.

94 Same as System 93, except that the shields were coupled to copper.

1 Systems were fabricated using b-pair, 19-gauge direct burial cables unless

otherwise indicated.
Internal

Composition

of

water

extract

44 £> Q 4-» I lit Si<v o oo

r-t *—

O s 3 « -5

IO

w oo *

lit

vT) «TJ O) o u

«-» rH 4» —

IA -4-i « O Pia T3 T3

41 91C

fl

fc. <v "O ca £-«-» 41 lit 3 41

<-» T3 •*-» at —

lit lit 41 41 H U*i i <Q 6 i C "O o •*“ 41 •*- E >

41 <it E

-o

—T3 -aJ

tit lo at

41

Q

C

a: t— < ca at
Table 3. Rating Code for the Corrosion Evaluation

of Shields in Cable Specimens

Rating

10

9

8

7

6+

6

5

4

3

2

1

0

Performance Degree of Corrosion

Excellent

Excellent

Very Good

Good

Good

Good

Fair

Poor

Poor

Very Poor

Very Poor

Very Poor

Unaffected. No indication of corrosion.

Superficial rust or etching on surface.

Uniform metal attack, rust, and/or slight localized

pitting.

Appreciable pitting over the surface, but no perforations through metal shield. Some minor delamination

or dissipation of metal lurgically or plastic-bonded

metals leaving cathodic metal intact.

Localized pitting: only one perforation in shield

by pitting.

Localized pitting: two to five perforations in

shield by pitting.

Many localized pits causing perforation of shield;

< 5 percent of shield dissipated by corrosion;

extensive delamination of metal! urgically bonded

metals.

Severe corrosion: pitting to perforation of shield;

five to ten percent of shield dissipated by corrosion

severe corrosion of anodic part of metallurgical ly

bonded metals.

Severe corrosion: pitting to perforation of shield;

ten to twenty-five percent of shield dissipated by

corrosion.

Severe corrosion: more than twenty-five percent of

shield dissipated by corrosion; shield still has

electrical continuity along the cable.

Severe corrosion: shield is close to electrical

discontinuity (ELD) due to perforation in shield and

dissipation of metal by corrosion.

Severe corrosion: shield is electrically discontinuous (ELD) due to dissipation of metal by

corrosion.
46

Table 4

Performance of Shields in Cable Specimens Buried Up

to Six Years in Sagemoor Sandy Loam (Site A)

Exposure

System

Time

(years)

Exposed

Wi ndow

Exposed

Ring

Under

Jacket

1/2 Inch

Wi ndow

1/2 Inch

Ring

Copper

Cathode

41 1 10 10 10 10 10

2 9 9 9 9 9

3 10 10 10 10 10

4 9 9 9 9 9

5 10 10 10 10 10

6 10 10 10 10 10

42 1 5 0 4 0 0 10

2 Destroyed 10

3 Destroyed 9

4 Destroyed 9

5 Destroyed 9

6 Destroyed 10

43 1 10 10 10 10 10

2 10 10 10 10 10

3 9 9 9 10 10

4 9(10) 10 10 10 10

5 10 10 10 10 10

6 10 10 8(10) 8(10> 8(10)

44 1 7 2 5(10) 7(10) 2(10) 10

2 0 0 0(10) 0(10) 0(10) 10

3 0 0 0(10) 0(10) 0(10) 10

4 0(9) 0(9) 0(9) 0(9) 0(9) Missing

5 0(10) 0(10) 0(5) 0(10) 0(10) Missing

6 0(10) 0(10) 0(10) 0(10) 0(10) 5

45 1 10 10 10 10 10

2 10 10 10 10 10

3 10 10 10 10 10

4 10 10 10 10 10

5 10 10 10 10 10

6 10 10 10 10 10

46 1 4 5 10 5 5 10

2 Destroyed 10

3 Destroyed 10

4 Destroyed 9

5 Destroyed 9

6 0 1 2 2 2 Missi ng
46 47

Table 4 (continued)

Exposure

Time Exposed Exposed Under 1/2 Inch 1/2 Inch Copper

System (years) Window Ring Jacket Window Ring Cathode

47 1 10(3) 10(5) 10 10 10

2 10(1) 10 10 10(5) 10

3 10(3) 10 10 10(7) 10

4 10(0) 10(5) 10 10(5) 10(9)

5 10(2) 10(5) 10(5) 10(5) 10(6)

6 10(5) 10(5) 10(5) 10(5) 10(5)

48 1 10(2) 10 10 10 10 10

2 10(7) 10(7) 10 10(4) 10(7) 9

3 10(0) 10(5) 10(9) 10(5) 10(5) 9

4 10(4) 10(5) 10 10 10 9

5 10(0) 10(4) 10(6) 20(5) 10(5) 9

6 10(5) 10(5) 10 10(5) 10(5) Miss

49 1 10 10 10 10 10

2 10(3) 10 10 10 10

3 10(5) 10(5) 10(9) 10(9) 10(9)

4 10(2) 10(5) 10(5) 10(5) 10(5)

5 10(0) 10(5) 10(5) 10(5) 10(5)

6 10(0) 10 10(5) 10(5) 10

50 1 10 10 10 10 10 10

2 10 10 10 10 10 9

3 10(2) 10(5) 10(5) 10(2) 10(5) 9

4 10(0) 10(5) 10(5) 10(4) 10(5) 9

5 10(5) 10(5) 10(5) 10(5) 10(5) 10

6 10(0) 10 10(5) 10 10 9

51 1 9 9 10 10 10

2 10(0) 10(5) 10(5) 10(5) 10(5)

3 10(0) 10(5) 10(5) 10(4) 10(5)

4 10(1) 10(5) 10(5) 10(5) 10(5)

5 10(5) 10(3) 10(7) 10 10(5)

6 10(9) 10(9) 10(9) 10(9) 10(9)

52 1 10 10 10 10 10 9

2 10(0) 10(5) 10(0) 10(0) 10(5) 9

3 10(0) 10(0) 10(0) 10(0) 10(0) 9

4 10(5) 10(5) 10(5) 10(5) 10(5) 10

5 10(5) 10(3) 10(5) 10 10(5) 9

6 10(4) 10(4) 10(4) 10(4) 10(4) 10

53 1 10

2 10

3 10

4 10

5 10
Table 4 (continued)

Exposure

Time Exposed Exposed Under 1/2 Inch 1/2 Inch Copper

System (years) Window Ring Jacket Window Ring Cathode

54 1 10

2 10

3 Not recovered

4 Not recovered

5 10

55 1 Not recovered

2 10

3 Not recovered

4 10

5 5

Mi ssing

56 1 10 10 10 10 10

2 10 10 10 10 10

3 10 10 10 10 10

4 10 10 10 10 10

5 10 10 10 10 10

6 10 10 10 10 10

57 1 10(4) 10(5) 10 10(5) 10(5) 10

2 10 10 10 10 10 10

3 10 10 10 10 10 10

4 10 10 10 10 10 10

5 10 10 10 10 10 10

6 10 10 10 10 10 9

58 1 9(10) 9(10) 8(10) 9(10) 9(10)

2 8(10 0(10) 2(10) 2(10) 1(10)

3 9(10) 9(10) 8(10) 9(10) 9(10)

4 0(10) 0(10) 0(10) 0(10) 0(10)

5 8(10) 8(10) 5(10) 8(10) 8(10)

59 1 8(10) 8(10) 8(10) 8(10) 8(10) 10

2 0(10) 4(10) 0(10) 0(10) 5(10) 9

3 8(10) 8(10) 8(10) 8(10) 8(10) 10

4 5(10) 5(10) 5(10) 5(10) 5(10) 10

5 8(10) 8(10) 8(10) 8(10) 8(10) 10

60 1 10(10)8 9(10)8 8(10)0 9(10)8 10(10)8

2 8(10)8 8(10)8 8(10)0 8(10)8 8(10)8

3 10(10)4 9(10)0 8(10)0 9(10)0 9(10)0

4 8(10)8 8(10)8 8(10)0 8(10)4 8(10)8

5 9(10)9 8(10)9 9(10)9 9(10)9 9(10)9
49

System

61

62

63

64

65

66

67

68

69

Table 4 (continued)

Exposure

Time Exposed Exposed Linder 1/2 Inch 1/2 Inch Copper

(years) Window Ring Jacket Window Ring Cathode

1 2(10)4 2(10)8 4(10)4 2(10)4 2(10)8 10

2 5(10)5 5(10)2 5(10)0 5(10)5 5(10)2 10

3 2(10)4 8(10)4 4(10)0 8(10)4 8(10)4 10

4 8(10)5 8(10)8 8(10)5 8(10)5 8(10)5 10

5 9(10)0 9(10)8 9(10)2 9(10)8 9(10)8 9

1

2

3

4

5

10

10

10

10

10

1

2

3

4

5

10

10

10

10

10

1

2

3

4

5

10

10

10

10

10

1

2

3

4

5

10

10

10

10

10

1

2

3

4

5

10 10

10 9

10 Missing

10 10

10 Missing

1

2

3

10

10

10

1

2

3

10

10

10

1

2

3

10

10

10
Table 4 (continued)

System

Exposure

Time

(years)

Exposed

Wi ndow

Exposed

Ring

Under

Jacket

1/2 Inch

Wi ndow

1/2 Inch

Ring

Copper

Cathode

70 1 10

2 10

3 3

73 1 9(10 9(10) 9(10) 9(10) 9(10)

2 4(10) 2(10) 9(10) 8(10) 8(10)

74 1 2(9) 1(9) 9(10) 5(9) 3(9) 10

2 4(10) 2(10) 9(10) 8(10) 8(10) 10

75 1 10(10) 10(10) 10(10) 10(10) 10(10)

2 8(10) 8(10) 10(10) 10(10) 10(10)

76 1 10(10) 10(10) 10(10) 10(10) 10(10) 10

2 8(10) 6+(10) 10(10) 10(10) 10(10) 10

77 1 10(10) 10(10) 10(10) 10(10) 10(10)

2 6(10) 6(10) 10(10) 10(10) 10(10)

78 1 10(10) 10(10) 10(10) 10(10) 10(10) 10

2 4(10) 1(10) 10(10) 10(8) 10(8) 10

79 1 10(10) 6(10) 10(10) 10(10) 10(10)

2 9(10) 10(10) 10(10) 10(10) 10(10)

80 1 10(10) 5(6) 9(10) 10(10) 9(10) 10

2 4(4) 4(4) 10(10) 10(5) 10(10) 10

81 1 10(10) 10(10) 10(10) 10(10) 10(10)

2 10(10) 10(10) 10(10) 10(10) 10(10)

82 1 6(10) 5(10) 10(10) 10(10) 10(10) 10

2 4(2) 3(5) 9(10) 8(10) 8(10) 10

83 1 10(10) 10(10) 10(10) 10(10) 10(10)

2 10(10) 10(10) 10(10) 10(10) 10(10)

84 1 Missing

2 10(10) 10(10) 10(10) 10(10) 10(10) 10

85 1 9(10) 9(10) 10(10) 10(10) 10(10)

2 10(10) 10(10) 10(10) 10(10) 10(10)

86 1 5(10) 6(10) 10(10) 10(10) 10(10) 10

2 5(10) 5(10) 10(10) 10(10) 10(10) 10
Table 4 (continued)

System

Exposure

Time

(years)

Exposed

Wi ndow

Exposed

Ring

Under

Jacket

1/2 Inch 1/2 Inch

Window Ring

Copper

Cathode

87 1 9(10) 9(10) 10(10) 10(10) 9(10)

2 6(10) 5(10) 10(10) 10(10) 10(10)

88 1 6(10) 5(10) 8(10) 8(10) 8(10) 10

2 8(10) 5(10) 10(10) 8(10) 10(10) 10

89 1 9 9 10 10 10

90 1 9 9 10 10 9 10

91 1 Destroyed

92 1 Destroyed

93 1 5(0) 5(0) 5(4) 5(0) 5(0)

94 1 Destroyed 10
Table 5. Performance of Shields in Cable Specimens

Buried Up to Six Years in Hagerstown Loam (Site B)

System

47

48

49

50

51

52

Exposure

Time

(years)

Exposed

Wi ndow

Exposed

Ring

Under

Jacket

1/2 Inch

Wi ndow

1/2 Inch

Ring

Copper

Cathode

1 10 10(5) 10 10 10

2 10 10 10 10(5) 10

3 10 10 10 10 10

4 10 10 10 10 10

5 10 10 10 10 10

6 10 10 10 10 10

1 10 10 10 10 10 10

2 10 10 10 10 10 9

3 10(5) 10 10 10 10 9

4 10(5) 10(5) 10 10 10 9

5 10 10 10 10 10 10

6 10(0) 10(5) 10 10(4) 10 9

1 10 10 10 10 10

2 10 10 10 10 10

3 10 10 10 10 10

4 10 10 10 10 10

5 10 10 10 10 10

6 10 10 10 10 10

1 10 10 10 10 10 10

2 10 10 10 10 10 9

3 10 10 10 10 10 9

4 10 10 10 10 10 9

5 10 10 10 10 10 10

6 10(5) 10 10 10 10 9

1 10 10 10 10 10

2 10 10 10 10 10

3 10 10 10 10 10

4 10 10 10 10 10

5 10 10 10 10 10

6 10 10 10 10 10

1 10 10 10 10 10 9

2 10 10 10 10 10 9

3 10(3) 10 10 10 10 9

4 10(0) 10(5) 10(6) 10(5) 10(5) 10

5 10(4) 10(5) 10 10(5) 10 10

6 10 10 10 10 10 8
Table 5 (continued)

System

55

62

63

64

65

66

67

69

Exposure

Time Exposed

(years) Window

Exposed Under 1/2 Inch 1/2 Inch Copper

Ring Jacket Window Ring Cathode

1 Not recovered

2

3 Not recovered

4 Not recovered

5

5

5

1

2

3

4

10

10

10

10

1

2

3

4

5

10

10

10

10

10

1

2

3

4

10

10

10

10

1

2

3

4

5

10

10

10

10

10

1

2

3

4

5

10

10

10

10

10

Not recovered

10

10

10

10

Not recovered

10

10

10

Missing

Missing
54

Table 5 (continued)

System

Exposure

Time

(years)

Exposed

Wi ndow

Exposed

Ring

Under

Jacket

1/2 Inch

Wi ndow

1/2 Inch

Ring

Copper

Cathode

70 1 10

2 10

3 10

73 1 2(10) 2(10) 10(10) 9(10) 9(10)

2 10(4) 10(3) 9(10) 8(10) 8(10)

74 1 0(10) 1(10) 9(10) 9(10) 5(10) 10

2 3(10) 2(10) 9(10) 8(10) 10(10) 10

75 1 10(10) 10(10) 10(10) 10(10) 10(10)

2 10(10) 10(10) 10(10) 10(10) 10(10)

76 1 5(10) 5(10) 10(10) 5(10) 5(10) 10

2 5(10) 5(10) 10(10) 5(10) 10(10) 10

77 1 10(10) 10(10) 10(10) 10(10) 10(10)

2 5(10) 6(10) 10(10) 8(10) 8(10)

78 1 2(10) 2(10) 10(10) 9(10) 9(10) 10

2 1(10) 1(10) 10(10) 8(10) 8(10) 10

79 1 6(10) 5(10) 10(10) 10(10) 10(10)

2 5(10) 5(10) 9(10) 8(10) 8(10)

80 1 2(10) 2(10) 9(10) 9(10) 10(10) 10

2 2(6+) 1(9) 8(9) 8(10) 9(10) 10

81 1 9(10) 5(10) 9(10) 9(10) 9(10)

2 3(10) 4(10) 9(10) 9(10) 9(10)

82 1 2(10) 2(10) 9(10) 9(10) 9(10) 9

2 1(10) 1(10) 9(10) 8(10) 8(10) 10

83 1 10(10) 10(10) 10(10) 10(10) 10(10)

2 10(10) 10(10) 10(10) 10(10) 10(10)

84 1 5(10) 5(10) 10(10) 10(10) 8(10) 10

2 6(10) 6(10) 10(10) 10(10) 10(10) 10

85 1 9(10) 4(10) 9(10) 4(10) 9(10)

2 6(10) 4(10) 10(10) 8(10) 9(10)

86 1 3(9) 3(9) 10(9) 9(9) 9(9) 10

2 2(10) 1(10) 10(10) 8(10) 10(10) 10
Table 5 (continued)

System

Exposure

Time

(years)

Exposed

Wi ndow

Exposed

Ring

Under

Jacket

1/2 Inch

Wi ndow

1/2 Inch

Ring

Copper

Cathode

87 1 5(10) 5(10) 9(10) 8(10) 8(10)

2 4(10) 4(10) 9(10) 8(10) 8(10)

88 1 3(10) 3(10) 8(10) 8(10) 8(10) 10

2 2(10) 1(10) 8(10) 8(10) 8(10) 10

89 1 9 9 9 9 9

90 1 9 9 9 9 9 10

91 1 5 8 9 8 9

92 1 Destroyed

93 1 9(2) 9(0) 9(0) 9(0) 9(0)

94 1 Destroyed 10
Table 6. Performance of Shields in Cable Specimens

Buried Up to Six Years in Clay Soil (Site C)

Exposure

System

Time

(years)

Exposed Exposed

Wi ndow Ri ng

Under

Jacket

1/2 Inch

Wi ndow

1/2 Inch

Ring

Copper

Cathode

41 1 9 9 10 9 9

2 10 5 10 10 10

3 0 0 0 1 0

4 Destroyed

5 Destroyed

6 0 3 4 5 6

42 1 Destroyed 10

2 0 0 5 5 5 10

3 Destroyed 6+

4 Destroyed 9

5 Destroyed 4

6 Destroyed 5

43 1 5 2 6(10) 5(10) 2(0)

2 6 0 8 5 0(10)

3 0 0 0(10) 0 0(10)

4 0(10) 1(10) 5(10) 2(10) 2(10)

5 0(10) 0(10) 0(10) 0(10) 0(10)

6 0(10) 0(10) 0(10) 0(10) 0(10)

44 1 2 0 0(10) 2(10) 0(10) 10

2 0 0 0(10) 0(10) 0(10) 10

3 0 0 0(10) 0(10) 0(10) 9

4 0(10) 0(10) 0(10) 0(10) 0(10) 9

5 0(10) 0(10) 0(10) 0(10) 0(10) Missing

6 0(10) 0(10) 0(10) 0(10) 0(10) 5

45 1 9 6+ 5 6+ 6

2 6 6+ 10 10 10

3 0 1 3 5 3

4 5 0 1 0 0

5 5 1 2 3 2

6 3 2 3 3 5

46 1 4 3 4 4 3 10

2 5 2 4 4 4 10

3 5 1 3 0 1 9

4 Destroyed 9

5 Destroyed 9

6 2 1 1 1 1 9
56 57

Table 6 (continued)

Exposure

Time Exposed Exposed Under 1/2 Inch 1/2 Inch Copper

System (years) Window Ring Jacket Window Ring Cathode

47 1 7(7) 10 10 10(5) 10(5)

2 9(2) 9(5) 10 10 10

3 9(1) 9(9) 9(10) 9(10) 9(10)

4 10(5) 10(5) 10(5) 10(5) 10(5)

5 10(1) 10(4) 10(5) 10(5) 10(5)

6 10(4) 10(4) 10(5) 10(5) 10(5)

48 1 9 9 9(10) 9(4) 9(4) 10

2 9(10) 9(10) 10 10(0) 10(1) 9

3 9(1) 9(5) 10(5) 10(5) 10(5) 9

4 10(3) 10(4) 10(5) 10(4) 10(5) 9

5 10(0) 10(4) 10(4) 10(4) 10(4) 9

6 10(0) 10(4) 10(0) 10(0) 10(3) 9

49 1 9 9 9 9 9

2 10(1) 10 10 10(6) 10(1)

3 9(1) 9(5) 10(9) 10(9) 10(9)

4 10(5) 9(5) 10(5) 10(5) 10(5)

5 Not recovered

6 10(0) 10(5) 10(3) 10(5) 10(5)

50 1 9(1) 9 9(8) 9(2) 9(2) 10

2 10(1) 10(4) 10(5) 10(1) 10(5) 9

3 10(1) 10(4) 10(2) 10(3) 10(5) 9

4 5(0) 9(0) 10(0) 10(0) 10(0) 9

5 10(0) 10(5) 10(2) 10(0) 10(5) 9

6 10(0) 10(0) 10(0) 10(0) 10(0) Missing

51 1 10(5) 9(5) 10 10(2) 10(4)

2 10(2) 10(5) 10(5) 10(5) 10(5)

3 10(0) 10(0) 10(0) 10(0) 9(0)

4 6(0) 10(5) 6(0) 10(0) 10(5)

5 10(5) 10(3) 10(4) 10(4) 10(5)

6 10(0) 10(0) 10(0) 10(0) 10(0)

52 1 10 10 10(5) 10(1) 10(3) 9

2 10(0) 10(5) 10(0) 10(0) 10(5) 9

3 10(0) 9(0) 10(0) 9(0) 10(0) 9

4 6(0) 10(0) 9(0) 10(0) 5(0) 9

5 10(0) 10(0) 10(0) 10(0) 10(0) 9

6 10(0) 10(0) 10(0) 10(0) 10(0) 9

53 1 10

2 10

3 10

4 10

5 10

6 10
58

Table 6 (continued)

Exposure

Time Exposed Exposed Under 1/2 Inch 1/2 Inch Copper

System (years) Window Ring Jacket Window Ring Cathode

54 1 10

2 10

3 1

4 10

5 Not recovered

6 0 9

55 1 Not recovered

2 5

3 Not recovered

4 5

5 2

6 Not recovered

56 1 10 10 10 10 10

2 10 10 10 10 10

3 10 10 10 10 10

4 10(2) 10 10 10 10

5 10 10 10 10 10

6 10(5) 10(5) 10(5) 10(5) 10(5)

57 1 10 10 10 10 10 9

2 10(5) 10(5) 10 10(5) 10(5) Missing

3 10(5) 10(5) 10 10 10 Missing

4 10(0) 10 10 10 10 10

5 10(0) 3(2) 10(0) 10(0) 10(3) 9

6 6(0) 10(0) 10(0) 9(0) 10(0) 9

58 1 8(10) 8(10) 8(10) 8(10) 8(10)

2 5(10) 5(10) 5(10) 8(10) 5(10)

3 0(10) 9(10) 0(10) 0(10) 0(10)

4 0(10) 0(10) 0(10) 0(10) 0(10)

5 2(10) 3(9) 4(10) 3(10) 9(10)

59 1 9(10) 9(10) 9(10) 9(10) 9(10) Missing

2 Not recovered

3 5(10) 5(10) 5(10) 5(10) 5(10) 10

4 10 10 8(10) 10 10 Missing

5 0(10) 0(5) 0(10) 10 0(10) Missing

60 1 8(10)8 8(10)8 8(10)4 8(10)4 8(10)8

2 8(10)8 8(10)8 8(10)6 8(10)6 8(10)8

3 8(10)4 8(10)8 8(10)2 8(10)4 8(10)8

4 8(10)4 8(10)6 8(10)2 8(10)8 8(10)8

5 9(10)2 9(10)2 9(10)0 9(10)0 9(10)0
Table 6 (continued)

Exposure

System

Time

(years)

Exposed

Window

Exposed

Ring

Under 1/2 Inch

Jacket Window

1/2 Inch Copper

Ring Cathode

61 1 8(10)0 10(10)5 8(10)0 8(10)0 10(10)5 10

2 8(10)2 8(10)0 8(10)0 8(10)2 8(10)0 Missing

3 8(10)0 8(10)0 8(10)0 8(10)0 8(10)0 Missing

4 9(10)0 9(10)0 9(10)0 9(10)0 9(10)0 Missing

5 9(10)0 9(10)0 9(10)0 9(10)0 9(10)0 Missing

62 1 10

2 10

3 10

4 10

5 10

63 1 10

2 10

3 10

4 10

5 10

64 1 10

2 10

3 10

4 5

5

• 10

65 1 10

2 10

3 10

4 10

5 10

66 1

2

3

4

5

67 1

2

3 Not recovered

10 10

10 Missing

10 Missing

10 Missing

10 Missing

10

10

68

1

2

3 Not recovered

10

10
73

74

75

76

77

78

79

80

81

82

83

84

85

60

Table 6 (continued)

Exposure

Time

(years)

Exposed

Wi ndow

Exposed

Ring

Under

Jacket

1/2 Inch

Window

1/2 Inch

Ring

1 10

2 10

3 Not recovered

1 10

2 10

3 10

1 9(10) 2(10) 9(10) 9(10) 5(10)

2 2(10) 2(10) 8(10) 8(10) 8(10)

1 1(10) 1(8) 9(10) 3(10) 2(10)

2 0(0) 0(3) 9(10) 8(8) 8(10)

1 10(10) 10(10) 10(10) 10(10) 10(10)

2 8(10) 8(10) 8(10) 8(10) 8(10)

1 2(10) 2(10) 10(10) 8(10) 6(10)

2 5(10) 4(10) 10(10) 5(10) 5(10)

1 6(10) 10(10) 10(10) 10(10) 10(10)

2 5(10) 4(10) 10(10) 8(10) 8(10)

1 2(10) 2(10) 10(10) 9(10) 10(10)

2 0(8) 0(4) 8(10) 1(10) 0(10)

1 Not recovered

2 5(10) 4(10) 10(10) 8(10) 8(10)

1 2(5) 2(2) 10(10) 10(10) 10(10)

2 0(0) 0(0) 8(8) 8(1) 8(3)

1 9(10) 6+(10) 10(10) 10(10) 10(10)

2 Not recovered

1 2(10) 1(5) 10(10) 9(10) 10(10)

2 0(0) 0(1) 9(10) 2(8) 4(8)

1 10(10) 10(10) 10(10) 10(10) 10(10)

2 10(10) 6(10) 10(10) 10(10) 10(10)

1 6(10) 6(10) 10(10) 10(10) 10(10)

2 5(10) 5(10) 10(10) 10(10) 10(10)

1 6+(10) 5(10) 9(10) 9(10) 9(10)

2 6(10) 4(10) 10(10) 8(10) 9(10)

Copper

Cathode

10

Missing

10

10

10

10

9

10

Missing

10

10

10
61

Table 6 (continued)

astern

Exposure

Time

(years)

Exposed

Wi ndow

Exposed

Ring

Under

Jacket

1/2 Inch

Wi ndow

1/2 Inch

Ring

Copper

Cathode

86 1 0(9) 1(0) 9(9) 9(9) 9(9) Missing

2 1(0) 0(0) 10(0) 8(0) 10(0) Missing

87 1 6(10) 5(10) 9(10) 8(10) 8(10)

2 4(10) 3(10) 8(10) 8(10) 8(10)

88 1 2(5) 1(10) 9(10) 0(10) 9(10) 10

2 1(0) 1(5) 8(10) 8(1) 8(10) 10

89 1 9(9) 9(9) 9(9) 9(9) 9(9)

90 1 9 9 9 9 9 10

91 1 0 1 9 9 9

93 1 9(0) 9(0) 9(0) 9(0) 9(0)
Table 7. Performance of Shields in Cable Specimens

Buried Up to Six Years in Lakewood Sand (Site D)

System

Exposure

Time

(years)

Exposed

Window

Exposed

Ring

Under

Jacket

1/2 Inch

Wi ndow

1/2 Inch

Ring

Copper

Cathode

47 1 10 10 10 10 10

2 10 10 10 10 10

3 10(8) 10(8) 10 10 10

4 10(5) 10(5) 10(5) 10(5) 10(5)

5 10(5) 10(5) 10(6) 10(5) 10

6 10(5) 10(5) 10(5) 10(5) 10(5)

48 1 9 9 9(10) 9(10) 9(10) 10

2 10(4) 9(10) 10 10 10 9

3 10(4) 10(5) 10(5) 10(5) 10(5) 9

4 10(4) 10(5) 10 10(5) 10(5) 9

5 10(5) 10(5) 10(5) 10(5) 10(5) 10

6 10(4) 10(5) 10(5) 10(5) 10 9

49 1 10 10 10 10 10

2 10 10 10 10 10

3 10(5) 10(5) 10 10 10

4 10(5) 10(5) 10 10(6) 10

5 10(4) 10(5) 10 10 10

6 10(2) 10(5) 10 10(5) 10

50 1 10 10 9(10) 10 10 10

2 10(9) 10(9) 10 9(10) 10 9

3 Not recovered

4 10(1) 10(5) 10(5) 10(5) 10(5) 9

5 10(0) 10(5) 10(5) 10(5) 10(5) 10

6 10(0) 10(5) 10 10(5) 10(5) 9

51 1 10 10 10 10 10

2 10 10 10 10 10

3 10 10(5) 10 10 10

4 10 10(6) 10(6) 10 10(6)

5 10(4) 10(5) 10 10 10(5)

6 10(5) 10(5) 10(5) 10(5) 10(5)

52 1 10 10 10 10 10 9

2 10(5) 10(5) 10(9) 10(5) 10(9) 9

3 10(0) 10(3) 10(6) 10(5) 10(3) 9

4 10(5) 10(5) 10(6) 10(5) 10(5) 10

5 10(0) 10(3) 10(5) 10(4) 10(4) 10

6 10(0) 10 10 10 10 9
62 63

Table 7 (continued)

Exposure

Time Exposed

System (years) Window

Exposed Under 1/2 Inch 1/2 Inch Copper

Ring Jacket Window Ring Cathode

53 1 10

2 10

3 10

4 10

5 10

6 10

54 1 10 Missing

2 10 Missing

3 10 Missing

4 10 Missing

5 10 9

6 10 Missing

55 1 10

2 10

3 10

4 10

5 6

6 6

56 1 10

2 10 10 10 10 10

3 10 10 10 10 10

4 10 10 10 10 10

5 10 10 10 10 10

57 1 Not recovered

2 10(5) 10(5) 10 10(5) 10 10

3 10(0) 10(4) 10 10(5) 10(5) Missing

4 10(6) 10(5) 10 10 10 10

5 10(0) 10(4) 10(5) 10(4) 10(4) 10

62 1 10

2 10

3 10

4 8

5 10

63 1 10

2 10

3 10

4 10

5 10
Table 7 (continued)

Exposure

Time Exposed Exposed Under 1/2 Inch 1/2 Inch Copper

System (years) Window Ring Jacket Window Ring Cathode

64 1

2

3

4

5

65 1

2

3

4

5

66 1

2

3

4

5

67 1

2 Not recovered

3

68 1

2

3

10

10

10

10

10

10

10

10

10

10

10 Missing

10 Missing

10 Missing

10 Missing

10 10

10

10

10 • 10

10

69

70

1 Not recovered

2 10

3 Not recovered

1 10

2 10

3 10

73 1 9(10) 6(10) 10(10) 9(10) 9(10)

2 8(10 4(10) 9(10) 8(10) 8(10)

74 1 5(10) 2(10) 9(10) 9(10) 4(10) 10

2 4(10) 4(10) 8(10) 8(10) 8(10) 10

75 1 10(10) 10(10) 10(10) 10(10) 10(10)

2 10(10) 10(10) 10(10) 10(10) 10(10)

76 1 10(10) 6+(10) 10(10) 10(10) 10(10) 10

2 5(10) 6(10) 10(10) 10(10) 10(10) 10
64 65

Table 7 (continued)

Exposure

a

gg

g

g

System

Time

(years)

Exposed

Wi ndow

Exposed

Ring

Under

Jacket

1/2 Inch

Wi ndow

1/2 Inch

Ring

Copper

Cathode

77 1 10(10) 10(10) 10(10) 10(10) 10(10)

2 8(10) 6(10) 10(10) 9(10) 9(10)

78 1 6(10) 5(10) 10(10) 10(10) 10(10) 10

2 5(10) 4(10) 10(10) 5(10) 10(10) 10

79 1 6+(10) 6(10) 10(10) 10(10) 10(10)

2 8(10) 5(10) 10(10) 9(10) 9(10)

80 1 8(10) 6(10) 10(10) 10(10) 10(10) 10

2 5(10) 4(10) 10(10) 8(10) 8(10) 10

81 1 9(10) 9(10) 10(10) 10(10) 10(10)

2 8(10) 5(10) 10(10) 10(10) 10(10)

82 1 5(10) 5(10) 10(10) 10(10) 10(10) 10

2 4(10) 2(10) 9(10) 9(10) 9(10) 10

83 1 10(10) 10(10) 10(10) 10(10) 10(10)

2 10(10) 10(10) 10(10) 10(10) 10(10)

84 1 10(10) 10(6) 10(10) 10(10) 10(10) 10

2 5(10) 5(10) 10(10) 10(10) 10(10) 10

85 1 10(10) 10(10) 10(10) 10(10) 10(10)

2 7(10) 5(10) 10(10) 10(10) 10(10)

86 1 5(10) 5(10) 10(10) 10(10) 10(10) 10

2 4(10) 4(10) 10(10) 8(10) 10(10) 10

87 1 7(10) 7(10) 9(10) 7(10) 8(10)

2 5(10) 5(10) 5(10) 8(10) 8(10)

88 1 6(10) 5(10) 8(10) 8(10) 8(10) 10

2 2(10) 3(10) 8(10) 8(10) 8(10) 10

89 1 10 9 9 10 10

90 1 9 9 9 9 10 10

91 1 9(9) 6(9) 9(9) 9(9) 9(9)

93 1 9(0) 9(0) 9(0) 9(0) 9(0)
Do

Table 8. Performance of Shields in Cable Specimens

Buried Up to Five Years in Coastal Sand (Site E)

System

Exposure

Time

(years)

Exposed

Wi ndow

Exposed

Ring

Under

Jacket

1/2 Inch

Wi ndow

1/2 Inch

Ring

Copper

Cathode

47 1 9 9(10) 9 9 9

2 10 10 10 10 10

4 10(5) 10(5) 10(5) 10(5) 10(5)

5 10(6) 10 10(5) 10(5) 10

6 10(5) 10(5) 10(5) 10(5) 10(5)

48 1 10 10 9(10) 9(10) 9(10) 10

2 10 10 10 10 10 9

4 10(2) 10(5) 10(4) 10(5) 10(2) 9

5 10(0) 10(5) 10(5) 10(4) 10(4) 9

6 10(0) 10(5) 10(5) 10(1) 10(5) 9

49 1 Not recovered

2 10 10 10 10 10

3 10 10 10(9) 10(9) 10(9)

4 10(5) 10(5) 10(5) 10(5) 10(5)

5 10(5) 10(6) 10(5) 10(6) 10(6)

6 10(2) 10 10(5) 10(3) 10(3)

50 1 9 9 9 9 9 10

2 10 10 10 10 10 9

3 10(1) 10(5) 10(5) 10(5) 10(5) 9

4 10(5) 10(5) 10(5) 10(5) 10(5) 10

5 10(5) 10(5) 10(5) 10(5) 10(5) 9

6 10(5) 10 10(0) 10(5) 10 9

51 1 10 10 10 10 10

2 10(5) 10(5) 10(9) 10(9) 10(9)

3 10(5) 10(5) 10(6) 10(5) 10(5)

4 10 10 10(6) 10(6) 10

5 10(2) 10(5) 10(5) 10 10(5)

6 10(4) 10(4) 10(4) 10(4) 10(4)

52 1 10(2) 10(5) 10 10(5) 10(5) 9

2 10(5) 10(5) 10(5) 10(5) 10(5) 9

3 10(0) 10(0) 10(0) 10(0) 10(0) 9

4 10(0) 10(3) 10(0) 10(0) 10(3) 9

5 10(0) 10(0) 10(0) 10(0) 10(0) 9

6 10(0) 10(0) 10(0) 10(0) 10(0) 9

53 1 10 10 10 10 10

2 10 10 10 10 10

3 10 10 10 10 10

4 10 10 10 10 10

5 10 10 10 10 10

6 10 10 10 10 10
Table 8 (continued)

Exposure

System

Time

(years)

Exposed

Wi ndow

Exposed

Ring

Under 1/2 Inch

Jacket Window

1/2 Inch

Ring

Copper

Cathode

54 1 10 10

2 10 9

3 10 9

4 5 Missing

5 10 9

6 9 9

55 1 10

2 10

3 10

4 10

5 10

6 10

56 1 10 10 10 10

2 10 10 10 10 10

3 10(5) 10(5) 10(7) 10(5) 10(6)

4 10(2) 10 10 10(5) 10

57 1 10(4) 10(4) 10(5) 10(5) 10(5) 9

2 10(0) 10(5) 10 10(5) 10(5) 10

3 10(0) 10(4) 10(5) 10(4) 10(4) Missing

4 10(4) 10(4) 10(4) 10(4) 10(4) 10

58 1 8(10) 8(10) 8(10) 8(10) 8(10)

2 5(10) 5(10) 5(10) 8(10) 5(10)

3 0(10) 0(10) 0(10) 0(10) 0(10)

4 0(10) 0(10) 0(10) 0(10) 0(10)

59 1 5(10) 5(10) 5(10) 8(10) 8(10) 10

2 5(10) 2(10) 0(10) 2(10) 2(10) Missing

3 5(10) 5(10) 5(10) 5(10) 5(10) 10

4 5(10) 3(10) 7(10) 5(10) 9(10) 10

60 1 8(10)8 8(10)8 8(10)8 8(10)8 8(10)8

2 8(10)8 8(10)4 8(10)5 8(10)8 8(10)4

3 8(10)4 8(10)5 8(10)4 8(10)4 8(10)4

4 8(10)4 8(10)4 8(10)0 8(10)2 8(10)4

61 1 10(10)0 10(10)0 10(10)0 10(10)0 10(10)0 10

2 10(10)2 10(10)0 8(10)0 10(10)3 10(10)2 Missing

3 10(10)0 10(10)0 10(10)0 10(10)0 10(10)0 10

4 10(10)0 10(10)0 10(10)0 10(10)0 10(10)0 Missing

5 10(10)0 10(10)0 10(10)0 10(10)0 10(10)0 10
64

65

66

73

74

75

76

77

78

79

80

81

82

83

68

Table 8 (continued)

Exposure

Time

(years)

Exposed

Window

Exposed

Ring

Under 1/2 Inch

Jacket Window

1/2 Inch

Ring

Copper

Cathode

1 10

2 10

3 10

4 8

1 10

2 10

3 10

4 10

1 10

2 10

3 10

4 10

1 10

2 10

3 10

4 10

1 10 10

2 10 Missing

3 10 10

4 10 Missing

1 9(10) 9(10) 9(10) 9(10) 9(10)

1 5(10) 2(10) 9(10) 9(10) 9(10) 10

1 10(10) 10(10) 10(10) 10(10) 10(10)

1 5(10) 4(10) 10(10) 2(10) 5(10) 10

1 6(10) 6(10) 10(10) 10(10) 10(10)

1 3(10) 2(10) 10(10) 9(10) 10(4) Mi ssing

1 9(10) 9(10) 6+(10) 6+(10) 9(10)

1 4(10) 4(10) 10(10) 10(10) 10(10) 10

1 5(10) 9(10) 9(10) 10(10) 9(10)

1 3(10) 3(10) 9(10) 10(10) 9(10) 10

1 10(10) 10(10) 10(10) 10(10) 10(10)
Table 8 (continued)

Exposure

System

Time

(years)

Exposed

Wi ndow

Exposed

Ring

Under

Jacket

1/2 Inch

Wi ndow

1/2 Inch

Ring

Copper

Cathode

84 1 10(10) 6(10) 10(10) 4(10) 9(10) 10

85 1 9(10) 6(10) 10(10) 10(10) 10(10)

86 1 5(9) 4(4) 10(9) 9(9) 10(9) 10

87 1 7(10) 7(10) 6(10) 9(10) 9(10)

88 1 5(10) 3(1) 9(10) 8(10) 8(10) 10
70

Table 9. Performance of Shields in Cable Specimens

Buried Up to Six Years in Tidal Marsh (Site G)

Exposure

System

Time

(years)

Exposed Exposed

Window Ring

Under

Jacket

1/2 Inch

Wi ndow

1/2 Inch

Ring

Copper

Cathode

41 1 5 2 6 6 6

2 5 5 5 5 5

3 10 10 6+ 10 10

4 Destroyed

5 Destroyed

6 Destroyed

42 1 Destroyed 10

2 Destroyed 10

3 Destroyed 9

4 Destroyed 9

5 Destroyed 9

6 Destroyed 9

43 1 5 8 5(10) 5(10) 6(10)

2 0 0 0(10) 0(10) 8

3 0 0 0(10) 0(10) 0(10)

4 0(10) 0(10) 0(10) 0(10) 0(10)

5 0(10) 0(10) 0(10) 0(10) 0(10)

6 0(10) 0(10) 0(10) 0(10) 0(10)

44 1 1 1 6(10) 1(10) 0(10) 10

2 0 0 0(10) 0(10) 0(10) 10

3 0 0 0(10) 0(10) 0(10) 9

4 0(10) 0(10) 0(10) 0(10) 0(10) 9

5 0(10) 0(10) 0(10) 0(10) 0(10) Missing

6 0(10) 0(10) 0(10) 0(10) 0(10) Missing

45 1 2 2 3 2 2

2 3 5 3 4 3

3 0 1 1 0 1

4 2 2 2 0 2

5 Destroyed

6 Destroyed

46 1 3 1 4 5 1 10

2 Destroyed 10

3 1 1 1 1 1 9

4 4 0 2 5 2 9

5 Destroyed Missing

6 Destroyed Missing
70 71

Table 9 (continued)

Exposure

Time Exposed Exposed Under 1/2 Inch 1/2 Inch Copper

System (years) Window Ring Jacket Window Ring Cathode

47 1 4 10 10 6(2) 10(5)

2 6(0) 5 10 10(0) 10(5)

3 10(4) 10(5) 10(4) 10(5) 10(5)

4 10(0) 9(0) 5(0) 3(0) 10(0)

5 10(0) 10(1) 10(2) 10(5) 10(2)

6 10(0) 10(0) 10(0) 10(0) 10(0)

48 1 6 9 9 6+ 9 10

2 0 9(3) 9(0) 9(0) 9(0) 10

3 6(0) 10(6) 9(6) 8(0) 9(6) 9

4 0 4(0) 10(0) 4(0) 9(0) 4

5 10(0) 10(0) 10(0) 10(0) 10(0) 9

6 10(0) 10(1) 10(0) 10(5) 10(1) Missing

49 1 5 10 10 10(2) 10

2 10(0) 10(1) 10(6) 10(0) 10(5)

3 1(0) 9(5) 10(0) 10(3) 10(5)

4 2(0) 10(4) 9(0) 3(0) 10(4)

5 10(0) 10(2) 10(2) 10(2) 10(3)

6 0 6(0) 8(0) 4(0) 8(0)

50 1 5 3 10(0) 6(2) 5 10

2 0 6 10(1) 9(1) 9(1) 10

3 4(0) 10(5) 10(5) 10(0) 10(5) 9

4 6(0) 5(0) 10(0) 10(0) 10(0) 5

5 5(4) 10(2) 5(3) 5(4) 10(2) 9

6 0 10(4) 1 5(1) 10(4) 9

51 1 6 10 10(0) 10(0) 10(4)

2 5(0) 6(0) 10(0) 10(0) 5(0)

3 10(0) 9(0) 9(0) 10(0) 9(0)

4 2(0) 10(0) 5(0) 10(0) 5(4)

5 10(0) 10(0) 10(0) 10(0) 10(0)

6 6(0) 10(0) 10(0) 10(0) 10(0)

52 1 10 10 10(0) 10(0) 10(4) 9

2 4(0) 9(0) 10(0) 10(0) 10(0) 7

3 10(0) 5(0) 10(0) 10(0) 10(0) 9

4 5(0) 10(0) 10(0) 10(0) 10(0) 9

5 1(0) 1(0) 1(0) 1(0) 1(0) 9

6 5(0) 5(0) 5(0) 5(0) 5(0) 9

53 1 10

2 10

3 10

4 10

5 10
Table 9 (continued)

Exposure

Time Exposed Exposed Under 1/2 Inch 1/2 Inch Copper

System (years) Window Ring Jacket Window Ring Cathode

54 1 10 9

2 10 9

3 10 9

4 10 < Missing

5 10 Missing

55 1 9

2 4

3 Not recovered

4 3

5 3

6 5

56 1 10 10 10 10 10

2 0 10(2) 10(0) 10(0) 10(5)

3 10(5) 10(2) 10(5) 10(5) 10(5)

4 0(0) 1(0) 10(0) 10(0) 10(0)

5 10(0) 10(1) 10(0) 10(0) 10(0)

6 0(0) 10(1) 10(0) 5(0) 10(1)

57 1 9(2) 9(3) 10(5) 9(3) 9(3) 9

2 0 5(0) 5(0) 4(5) 10(0) 9

3 0 9(4) 9(5) 5 10(3) Missing

4 0 0(4) 0 0 0 Missing

5 0(0) 2(2) 10(0) 1002 10(2) Missing

6 0(0) 0(0) 5(0) 3(0) 3(0) 3

58 1 9(10) 8(10) 5(10) 9(10) 9(10)

2 0(10) 0(10) 0(10) 0(10) 0(10)

3 8(10) 8(10) 8(10) 8(10) 8(10)

4 5(9) 3(9) 7(10) 6(10) 6(10)

5 0(6) 0(10) 0(10) 0(10) 0(10)

59 1 8(10) 8(10) 8(10) 8(10) 8(10) 9

2 0(10) 0(10) 0(10) 0(10) 0(10) Missing

3 8(10) 8(10) 8(10) 8(10) 8(10) 9

4 0(0) 9(10) 5(10) 3(3) 10 9

5 6(10) 0(5) 0(6+) 0(4) 0(10) 9

60 1 5(10)3 8(10)8 8(10)0 8(10)0 8(10)8

2 3(10)0 2(10)0 2(10)0 3(10)0 3(10)0

3 0(10)0 0(10)0 0(10)0 0(10)0 0(10)0

4 4(10)0 8(10)0 8(10)0 8(10)0 8(10)0

5 Not recovered
Table 9 (continued)

Exposure

Time Exposed Exposed Under 1/2 Inch 1/2 Inch Copper

System (years) Window Ring Jacket Window Ring Cathode

1 10(10)0 10(10)4 8(10)0 10(10)0 10(10)8 9

2 10(10)0 10(10)0 10(10)0 10(10)0 10(10)0 9

3 10(10)0 10(10)0 10(10)0 10(10)0 10(10)0 9

4 10(10)0 10(10)0 9(10)0 10(10)0 10(10)0 9

5 9(10)0 9(10)0 10(10)0 10(10)0 10(10)0 9

62 1

2

3

4

5

6+

5

10

5

10

63 1

2

3

4

5

10

5

10

5

5

64 1

2

3

4

5

10

10

10

5

5

65 1

2

3

4

5

10

10

10

10

10

73

74

75

76

77

1 9(10) 9(10) 10(10) 9(10) 9(10)

2 0(10) 1(10) 9(10) 8(10) 8(10)

1 0(10) 1(5) 9(9) 9(9) 3(5) 10

2 0(0) 0(0) 8(0) 2(0) 0(0) 10

1 10(10) 10(10) 10(10) 10(10) 10(10)

2 1(10) 5(10) 10(10) 5(10) 5(10)

1 1(10) 10(10) 10(10) 10(10) 10(10) 10

2 0(10) 0(10) 5(10) 0(10) 4(10) 10

1 4(10) 1(10) 10(10) 10(10) 10(10)

2 0(10) 0(10) 10(10) 3(10) 0(10)

1 10(2) 10(0) 10(4) 9(0) 10(0) 10

2 0(0) 0(0) 8(4) 8(0) 3(0) 10

78
79

80

81

82

83

84

85

86

87

88

89

90

91

92

Table 9 (continued)

Exposure

Time

(years)

Exposed Exposed

Wi ndow Ri ng

Under

Jacket

1/2 Inch

Window

1/2 Inch

Ring

Copper

Cathode

1 5(10) 1(2) 9(10) 9(10) 9(10)

2 1(3) 2(3) 8(10) 8(10) 8(10)

1 0(0) 1(1) 10(10 6(10) 10(10) 10

2 Destroyed 10

1 5(10) 5(10) 10(10) 10(10) 10(10)

2 4(10) 5(10) 10(10) 8(10) 10(10)

1 1(10) 1(10) 9(10) 9(10) 9(10) 10

2 Destroyed 10

1 2(10) 5(10) 10(10) 10(10) 10(10)

2 5(3) 5(3) 10(10) 8(8) 4(8)

1 7(10) 5(6) 10(10) 10(10) 10(10) 9

2 0(10) 0(10) 9(10) 2(10) 2(10) Missing

1 5(10) 4(1) 10(10) 10(10) 10(10)

2 Destroyed

1 0(0) 0(1) 9(5) 9(3) 9(2) 10

2 Destroyed

1 6(10) 3(10) 8(10) 8(10) 8(10)

2 0(4) 0(3) 8(5) 8(5) 8(5)

1 0(0) 0(0) 8(8) 8(4) 8(4) 9

2 Destroyed

1 9 9 9 9 9

1 9 9 9 9 9 9

1 Destroyed

1 Destroyed
NBS-114A (rev. 2 -ac) U.S. DEPT. OF COMM.

BIBLIOGRAPHIC DATA

SHEET (See instructions)

4. TITLE AND SUBTITLE

PUBLICATION OR

REPORT NO.

2. Performing Organ. Report No. 3.

NBSIR 81-2243

Publication Date

April 1981

Corrosion Evaluation of Underground Telephone Cable Shielding Materials

5. AUTHOR(S)

W. F. Gerhold and J. L. Fink

6. PERFORMING ORGANIZATION (If joint or other than N BS, see instructions) 7. Contract/Grant No. national bureau of standards

DEPARTMENT OF COMMERCE *. Type of Report & Period Covered

WASHINGTON, D.C. 20234

9.

SPONSORING ORGANIZATION NAME AND COMPLETE ADDRESS (Street. City. State, ZIP)

Rural Electrification Administration

Department of Agriculture

Washington, D.C. 20250

10.

SUPPLEMENTARY NOTES

1 1 Document describes a computer program; SF-185, FIPS Software Summary, is attached.

11.

ABSTRACT (A 200-word or less factual summary of most significant information. If document includes a significant

bibliography or literature survey, mention it here)

Corrosion data is given on the performance of base and plastic coated metals intended

for use as cable shields for buried telephone cable. The materials investigated on specially prepared specimens were buried for periods up to six years in six different

soil environments. Metals tested included homogeneous plastic-bonded and metallurgically-bonded laminates. Some specimens were exposed bare (uncoated), while others

had plastic coatings or other types of coatings on either one or both sides. Metals

studied included aluminum, copper, low carbon steel and stainless steel alloys.

12. KEY WORDS (Six to twelve entries; alphabetical order; capitalize only proper names; and separate key words by semicolons)

alloys; corrosion; metals; metallurgically-bonded; plastic-bonded; soils; telephone

cables; underground

13. AVAILABILITY 14. NO. OF

| yj/Unl imited HI For Official Distribution. Do Not Release to NTIS

PRINTED PAGES

77

| ! Order From Superintendent of Documents, U.S. Government Printing Office, Washington, D.C.

20402. 15. Price

Order From National Technical Information Service (NTIS), Springfield, VA. 22161

$9.50

USCOMM-DC 6043-P80
X

<t1