A11105

nbs

PUBLICATIONS

NBSIR 82-2509

Corrosion Evaluation of

Underground Telephone Cable

Shielding Materials

U.S DEPARTMENT OF COMMERCE

National Bureau of Standards

Materials Chemistry Division

Washington, DC 20234

June 1 982

Prepared for

^ ^

'al Electrification Administration

lartment of Agriculture

lyj ;hington, DC 20250

Udu

62-Z5U9

B62

rtVTOJ3/-L BTJ*RAa

OV 8TAlO>AiD€

LIUHAJIT

NBSIR 82-2509 JUL 2 1 1982

(\O\cKC0

CORROSION EVALUATION OF

UNDERGROUND TELEPHONE CABLE

SHIELDING MATERIALS

J. L. Fink, E. Escalante, and W. F. Gerhold

U.S. DEPARTMENT OF COMMERCE

National Bureau of Standards

Materials Chemistry Division

Washington, DC 20234

June 1 982

DISTRIBUTION OF THIS DOCUMENT IS UNLIMITED

Prepared for Rural Electrification Administration

Department of Agriculture

Washington, DC 20234

'"»€au Of

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

NATIONAL BUREAU OF STANDARDS, Ernest Ambler, Director
K

- '•

AAiLaOMATC T9

tAJuiJuj

: £ JUt

h

!%'5»

'1.

•# «

‘1&

il'^ Mf.

I'l

•:«« ts 1?l«;§‘j< 30 MOITAUJAVS WO'CxiFtflOO

W3U3T bvtwoflopoatflu

^jAiHatAwi anajiiHB

eg

t(^irtUD -W t-ne ,f4rt4l*3«3'.^

i.

^ 'f.A'

' 3a^Ah.’»«VA 'e

• * * •'* '***; -M • • 'y ‘W I :> «

-

• ' *if^ *i

. , , . -fe /i’> -V- •

‘ / • w;, Ut

30 >^&ii

- N. • •*'^*'* ^ y|-»i_

A

i»^4tbi<:a mli>alKM 30fli3f^M00 ^6 TW3MY«Aq3Q ,^M #;

.>*<1 ,n»kknA I»»*i'r3 .iSC|[AG;#)ATS UASRUa^JAklOlTA Irt

r/\::.
CORROSION EVALUATION OF UNDERGROUND TELEPHONE CABLE SHIELDING MATERIALS

J. L. Fink, E. Escalante, and W. F. Gerhold

Corrosion and Electrodeposition Group

Materials Chemistry Division

National Bureau of Standards

Washington, DC 20234

INTRODUCTION

The increase of 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 cable

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 summarizing the results

obtained for these materials and the additional systems after burial for

periods of up to six years were presented at the Corrosion/74 [2] and

Corrosion/76 Symposia [3]. This paper (the fifth report) contains additional

data for some of the systems included in the earlier reports. Table 1 describes

the various cable systems includad in this report.

1
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 ranges from extreme acidity (4.0)

to high alkalinity (8.8). The electrical resistivity of the soils ranges 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,

^he 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:

Saqemoor 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 -devel oped soils found in the eastern part of the United

States. The site is located at the Loch Raven Reservoir of the Baltimore City

2
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 saH 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.

3
Tidal marsh (Site G) is a soil typical of the poorly-drai ned 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 ’che 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 shov/n 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 tne ring was an exposed

area 0.5 inch (1.3 cm) wide around the ci rcumferenca 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

v/ere sealed with a sealing compound and wrapped with vinyl tape to prevent

entry of moisture at the end areas.

4
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 surrounding area one-half inch around the exposed window, the

jacketed surrounding 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. It should be noted that at the time of this report

specimens of Site A had not been recovered since the underground corrosion

removals of 1979 and that the results indicated are those of the fourth NBS

report, NBSIR 81-2243 [4]. Specimens of selected systems with varying

degrees of corrosion are shown in figures 2 through 37. The words "tacky"

and "semi-tacky" are used to describe the filling compound used in the exposed

specimens. Specimens with filling compounds were tacky at the time of installation. 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 sufficient to

5
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 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 various systems and their performance

in the six soil environments in which the specimens were exposed are described

below.

System 56 . This system consisted of a 3-mil (0.1 mm) Type 430 stainless

steel outer shield bonded to a 3-mil (0.1 mm) 1100 aluminum alloy inner

shield with a clear flooding compound on the core side.

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

on specimens exposed 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, four, and six years at Site E. In general, the inner shield

was at or near ELD on specimens exposed from two to six years at Site G.

^ 6
The filling compound was still tacky except 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. The 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. For the specimens buried

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

jacketed and unjacketed areas. The inner shield of specimens buried at Site D

for three and five years and at Site E for two and three years were ELD at the

unjacketed window, while all areas exposed at Site E on the inner shield for

six years were ELD. Similarly, the inner shield of specimens exposed at

Site G was ELD at all examined areas, while only the window and ring areas

were ELD on the outer shield for the same exposed time.

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

corroded.

System 58 . This system consisted of a 3-mil (0.1 mm) Type 304 stainless

steel outer shield with a 4-mil (0.1 mm) vapor deposited aluminum alloy

coating on the inner shield.

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

7
The outer shield was unaffected by corrosion at Sites A and E for up to

six years. Nil or superficial corrosion was noted on specimens from Site C

for up to three years of exposure. The outer shield at Site C buried for six

years was noted as having superficial corrosion at all areas examined, while

all areas examined on the inner shield were ELD or near ELD. Corrosion in

varying degrees was noted on the cuter shield after being buried up to six years

at Site G. However, the inner shield at the same site was ELD at all areas

examined. The specimen at Site E was not installed for the six year exposure

because of a lack of material.

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.

Coupling this system zo copper accelerated corrosion of both shields.

With few exceptions, corrosion was superficial or nil on the outer shield

exposed up to five years at Sites A and C, and six years at Site E. Specimens

buried for five and six years at Site G were perforated due to corrosion on the

outer shield at all areas examined, while the inner shield was ELD for

specimens exposed for two to six years. All areas of the inner shield were

also ELD for specimens buried for two to six years at Site E.

System 60 . This system consisted of a 3-mil (0.1 mm) Type 304 stainless steel shield with a 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 tne stainless steel on any of the

specimens buried for up to five years at these sites. With very few exceptions,

the stainless steel shield was unaffected by corrosion at all areas examined

for specimens buried for up to six years at Sites A, C, and E. The stainless

8
steel shield for specimens from for the six year exposure at Site G was

perforated at and adjacent to the window area as well as at the jac;<eted

areas examined. The vapor deposited aluminum coated outer shield was near

ELD at all areas except for the area adjacent to the ring on the specimen

buried up to five years at Site A, while the vapor deposited aluminum inner

shield showed slight corrosion at all areas. Both inner and outer vapor

deposited aluminum shields of specimens buried for five and six yea'^s at

Site C were at or near ELD, while companion specimens at Site G were ELD

for two through six years at all areas examined. The outer aluminum shield

at and adjacent to the window and/or ring areas of specimens buried for

four years at Site E were ELD. The inner aluminum shield at tne jacketed

areas was ELD for the same exposure time. The specimen at Site E was not

installed for the six year exposure because of a lack of material.

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.

Coupling this system to copper accelerated corrosion on the inner and

outer vapor deposited aluminum coating at all four sites. In general, the

stainless steel shield specimens exposed at Sites A and E for uo to five

years were unaffected by corrosion. However, the stainless steel shield

specimens exposed at Site G for up to six years were perforated due to

corrosion at nearly all areas examined. With few exceptions, the stainless

steel shields exposed at Site C for two, four, and six years were unaffected

by corrosion. Perforation due to severe corrosion on tht inner aluminum

shields exposed at Site A was observed, while ELD or near ELD of the outer

aluminum shield of specimens buried up to five years was evident. Specimens

exposed for two through six years at Sites C, E, and G were ELD at all

areas on the inner and outer aluminum shield examined.

9
System 62 . This system consisted of a 50-pair, 22-gauge air core

cable having an 8-mil (0.2 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 shell.

The performance of this system was excellent after exposure for five

years at Sites A and C and for four years at Site B. Specimens exposed up

to six years at Sites 0 and E were unaffected by corrosion with the exception

of the specimens exposed for four years. Perforation due to localized

pitting corrosion was noted for specimens exposed at Site G for two and

four years, while companion specimens exposed for three and five years were

unaffected by corrosion. Specimens from Sites C and G showed minor degradation

after exposure for six years.

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

an S-mil (0.2 mm) uncorrugated aluminum alloy shield bonded on 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 Site A

and for six years at Sites B, C, D, and E. The shields of specimens buried

for two, four, and five years at Site G were perforated due to corrosion,

while companion specimens exposed for one, three, and six years were unaffected

by corrosion. Slight dissipation was noted at the sheared ends of the

specimens.

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

an 8-mil (0.2 mm) uncorrugated aluminum alloy shield bonded on both sides

to a 2-mil (0.05 mm) 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.

10
Specimens exposed for four years at Site B, five years at Site A, and

six years at Sites D and E were unaffected by corrosion. Only four specimens

were buried at Site B due to a lack of sufficient material to allow for a

five and six year exposure. Pitting corrosion which resulted in perforation

of the shield v/as observed on the specimens buried for four years at Site C

and specimens exposed for four, five, and six years at Site G. The shield

of the specimen from Site C buried for six years showed minor degradation.

Slight dissipation at the sheared ends of the specimens was observed at all

sites.

System 55 . Tnis system consisted of a 25-pair, 24-gauge cable having

an 8-mil (9.20 mm) uncorrugated aluminum alloy shield bonded on 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.

There was no apparent corrosion on specimens of this system after

exposure for five years at Site A and for six years at Sites B, C, 0, E,

and G

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

shield v/as coupled to copper.

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

These specimens were unaffected by corrosion after exposure for up to

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

System 67 . This system consisted of 4-mil (0.1 mm) aluminum foil [3

3/4 in. X 3 in. (9.5 cm x 20.3 cm)] coaced on both sides with a 5-mil (0.15

mm) ethylene acrylic acid copolymer.

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

11
There was no apparent degradation of specimens of this system after

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

(Specimens buried for two years at Sii:es B and 0 and for three years at

Site C were not recovered.)

System 68 . This system consisted of 4-mil (0.1 mm) aluminum foil

[3 3/4 in. X 8 in. (9.5 cm x 20.3 cm)] coated on both sides with a 6-mil

(0.15 mm) polyester film.

These specimens were exposed at Sites A, B, C, and D only.

Specimens of this system were unaffected by corrosion after exposure for

three years at Site A and up to four years at Sites B, C, and D.

System 59 . This system consisted of 4-mil (0.1 mm) aluminum foil

[1 1/2 in. X 12 in. (3.3 cm x 30.4 cm)] coated on both sides with a 5.5 mil

(0.14 mm) polyester film.

These specimens were exposed at Sites A, B, C, and D only.

Corrosion of specimens of this system was nil for up to three years at

Site A and for up to four years at Sites B, C, and D. (Specimens exposed

for one and three years at Site D and for three years at Sites B and C were

not recovered.

)

Sysi:em 70 . Specimens of this system (Table 1) were exposed at Sites A,

B, C, and D only.

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

up to four years at Sites B, C, and D. Severe corrosion was observed for

the specimen exposed at Site A for three years. More than 25 percent of the

metal bhield was dissipated due to corrosion. There was no window or ring on

specimens of this system.

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

this report.

12
System 73 . In general, the inner and outer shield of specimens of

this system (Table 1) exposed for one year at all sites were unaffected by

corrosion. Degradation of the outer black plate steel shield was severe at

the unjacketed window and ring areas on the specimen buried at Site B fcr

up to three years. The shield was near ELD at the unjacketed ring area for

specimens buried for three years. The outer shield of specimens exposed at

Site A for two years and at Sites C and D for two and three years was

severely corroded at the unjacketed window and/or ring areas. Perforation

due to corrosion at the window areas of the outer shield of specimens

exposed for two years at Site E was noted. In general, the inner aluminum

alloy shield was unaffected by corrosion except at Site G where ELD or near

ELD was observed at or adjacent to ring areas on specimens exposed for

three years. The outer shield exposed for three years at Site G was ELD at

all areas examined, except for the jacketed areas.

The filling compound was tacky except at corroded areas.

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

shields were coupled to copper.

Coupling specimens of this system to copper accelerated corrosion of

the shields at unjacketed areas. With few exceptions corrosion on the

inner shields of specimens buried up to three years at all sites was nil or

superficial. Specimens at Site B were ELD or near ELD for the first three

years of exposure at the window and/or ring areas, while the adjacent

window and ring areas were severely corroded. Severe degradation was noted

at the window and/or ring areas exposed for one, two, and three years at

Sites D and E. Of the specimens buried at Site G all areas examined on the

inner shield were ELD after two and three years of exposure. The outer

shield at the window area was ELD on specimens exposed at Site G for one.

13
two, and three years, while the ring and adjacent ring area was ELD on

specimens buried for two and three years.

The filling compound was still tacky except at corroded areas.

System 75 . The inner aluminum alloy shield on specimens of this

system (Table 1) exposed for up to three years at all sites was unaffected

by corrosion. The outer steel shield on specimens buried at Sites C, E,

and G for one year, Sites A and B for up to two yea>^s, and Site D for up to

three years was also unaffected by corrosion. Corrosion was superficial

or nil on specimens buried at Sites D and E for three years.

With one exception, corrosion at all areas examined, on both shields

was nil on specimens buried for one to three years at Site C. The outer

shield exposure showed slight corrosion at all areas examined after two

years of exposure at the same site. At Site G the window area was near ELD

for the specimen buried for two years and near ELD at the ring area after

three years exposure.

The filling compound was still tacky except at corroded areas.

System 76 . Same as System 75 except that the shielas 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 aluminum alloy shield of the specimens buried for

up to three years. With one exception, the outer steel shield was corroded

to varying degrees at unjacketed areas on all specimens exposed for up to

three years. Corrosion at these areas was most severe on specimens buried

at Sites C, E, and G. The outer shield of the specimens buried for tv/o

years at Site G was ELD at the window and ring areas. Both ring and jacketed

areas were ELD after exposure at this site for three years. The outer shield

of the specimen buried for one year at Site A was unaffected by corrosion.

14
The filling compound was still tacky except at corroded areas.

System 77 . The aluminum alloy inner shield on specimens of this

syscem (Taole 1) were unaffected by corrosion after exposure for up to

three years in all soils with the exception of one specimen at Site G.

There was no degradation of the outer steel shield of specimens buried for

one year at Sites A, B, and D. After exposure for three years, corrosion

of the outer shield was superficial or nil at jacketed areas for all specimens

except for those exposed at Sites B and C. Corrosion of the outer shield

was observed at the window and ring areas of all specimens buried for two

and three years in all soils. Perforation due to localized pitting corrosion

was noted at window and ring areas on specimens buried at Sites A and D for

two years and at Sites B, C, and E for up to three years on the outer

shielo. The specimens exposed at Site G for two and three years were ELD

at and adjacent to tne window and/or ring areas.

The filling compound was still tacky except at corroded areas.

System 7 8. Same as System 77 except that the shields were coupled to

copoer.

Coupling the shields to copper accelerated corrosion of the outer

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

inner shields of specimens bur''ed for three years at Sites B and D were

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

at Sites C and G occurred at the window and/or ring areas. For specimens

buried at Site G for up to three years , the inner snield 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 specimens buried

for two and three years at Sites B, C, and G, the outer shield was at or

15
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 three years at Site E.

The filling compound was still tacky except at corroded areas.

System 79 . Except for the specimens of this system (Table 1) buried

at Site G, there was no degradation of the inner aluminum alloy shield on

any of the specimens buried up to three years. Severe corrosion was noted

on the inner shield at the window and ring areas on specimens exposed for

up to three years at Site G. In general, corrosion of the outer steel

shield occurred at or adjacent to the un jacketed window and ring areas.

Perforation due to corrosion at the jacketed and adjacent window areas was

observed after exposure for one year at Site E. At the same site, the

wincow and ring areas on the outer steel shield were perforated due to

corrosion for specimens exposed for two and three years. The specimen

buried for up to three years at Site G was at or near ELD at or adjacent to

window and ring areas.

The filling compounds were still tacky at all uncorroded areas, while

corroded areas were noted as dry.

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

copper.

Coupling specimens of this system to copper accelerated 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 and C for

two years and Sites D and E for three years. The inner aluminum alloy

shield was perforated due to corrosion at unjacketed window and ring areas

on specimens buried up to three years at all sites. Specimens exposed for

three years at Sites B, C, and G were ELD at the window and ring areas on

16
the outer steel shield and were ELD on both shields of specimens exposed at

Sites C and G for the same time. All areas examined on the inner and outer

shields for specimens buried at Site G for two and three years were ELD and

were considered destroyed.

The filling compounds were still tacky at all uncorroded areas, while

corroded areas were noted as dry.

System 81 . There was no corrosion of the inner aluminum alloy shield

for specimens of this system (Table 1) after exposure for one and two years

at Sites A and G and up to three years at Sites B, C, D, and E. Corrosion

of the steel outer shield in varying degrees was noted at un jacketed window

and/or ring areas of specimens exposed up to three years at Sites B, C, D,

and E. The inner and outer shields at the unjacketed window and ring areas

of the specimens were ELD after the third year of exposure at Site G.

However, only the inner shield was ELD at the adjacent ring after the same

amount of time.

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

copper.

Coupling specimens of this system to copper accelerated corrosion of

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

inner and outer shields at jacketed areas exhibited little or no corrosion

after exposure at Sites A and B for up to two years and at Sites C, D, and E

for up to three years. Severe corrosion was observed on the outer steel

shield at the window and/or ring areas of specimens buried at Site A for

two years and at Sites D and E for up to three years. The outer shield at

the window and ring areas was severely corroded after exposure of one year

at Site B as were the adjacent window and ring areas of the outer shield

after exposure for three years. Specimens buried for two and three years

17
at Site B and one year at Site G were ELD at the window and ring areas,

while specimens exposed at the same site for two and three years were ELD

at all areas examined and were considered destroyed.

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

System 83 . With few exceptions specimens of this system (Table 1)

were unaffected by corrosion. Specimens exposed at Site C were perforated

due to corrosion on the outer steel shield at the window and ring areas for

specimens exposed up to two years and severely corroded at the same areas

after three years. The aluminum alloy inner shield of specimens exposed

for two years at Site G shewed slight corrosion at the adjacent window areas,

while severe corrosion was observed at the window and ring areas of specimens

buried at the same site for the same amount of time. Perforation was noted at

the window and ring areas of the outer shield for specimens exposed at Site G

for two years and at the adjacent ring area of specimens exposed for up to

three years. The window area of the outer shield was near ELD on the specimen

buried for three years at Site G.

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. The specimen at Site A was unaffected by corrosion after an exposure

of two years. Varying degrees of corrosion were noted at the unjacketed

window and ring areas on the outer shield of specimens buried up to three

years. Perforation due to corrosion was observed at the unjacketed window

and/or ring areas for specimens exposed at Sites B, C, and E for up to

18
three years, and at Site D for two and three years. The outer shield of

the specimen exposed for two years at Site G was ELD at the un jacketed

window and ring areas. However, ELD was observed on both shields at the

same areas of specimens exposed at Site G for three years. All inner

shield areas except the adjacent window area were ELD afte*^ exposure for

three years at Site G.

The filling compounds were semi -tacky to dry for all specimens.

System 85 . With few exceptions specimens of this system (Table 1)

were noted as having superficial or nil degradation on the inner aluminum

alloy shield exposed up to three years in all soils. The inner shield at

the unjacketed ring area was near ELD on the specimen buried at Site G for

one year. Companion specimens buried for two and three years at tne same

site were severely corroded at all areas examined and were considered

destroyed. The corrugated steel outer shield was unaffected by corrosion

on specimens at Site A buried for two years. Perforation due to severe

corrosion was noted at the un jacketed window and/or ring areas on the outer

shields of specimens exposed for three years at Sites 8, C, D, and E.

Slight degradation of the inner shield at and adjacent to the window of the

specimen exposed at Site C was observed for the three year exposure.

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 the unjacketed areas. The inner aluminum alloy

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

examined. The companion specimen exposed for three years at the same site

was ELD at and adjacent to window and/or ring areas. Severe corrosion of both

19
shields was noted on specimens buried up to three years at Site G. The

inner shield on the specimen exposed for one year at Site G was perforated

due to corrosion at all areas examined, while corrosion on the outer steel

shield at jacketed areas was negligible. Specimens buried at the same site

were ELD on the outer shield at the un jacketed window and ring areas after

one year exposure. Both shields were ELD at all area examined for specimens

exposed at Site G for two and three years and were considered destroyed.

With few exceptions for the specimens buried in the other four sites for

three years, both shields were perforated to severely corroded at all areas

exami ned.

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

System 87 . There was no degradation of the corrugated aluminum alloy

inner shield on specimens of this system (Table 1) buried up to three years

in four of the six soils. The inner shield of the specimen exposed for two

years at Site G was perforated due to corrosion at all areas examined,

while the companion specimen exposed for three years was ELD at all areas

on both the inner and outer shield and was considered destroyed. Perforation

due to localized pitting corrosion at the window and ring areas on the

steel outer shield was noted for specimens exposed at Site A for one and two

years and at Site D for two and three years. Companion specimens at Sites B, C,

and E buried up to three years were perforated or severely corroded at or

adjacent to window and ring areas.

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

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

copper.

Coupling specimens of this system to copper accelerated the corrosion

of the black plate steel outer shield at the window and ring areas after an

20
exposure of up to three years in all soils. In general, the performance of

the outer shields at unjacketed areas was fair to very poor for specimens

buried at the six sites. Corrosion of the corrugated aluminum alloy inner

shield was nil at all areas examined for up to three years in four of the

six soils. The inner shield of the specimen buried for three years at Site

C was ELD at all areas examined. Both shields of specimens exposed at Site

G for two and three years were ELD at all areas rated, and were considered

destroyed.

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

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

cable having a 5-mil (0.1 mm) corrugated copper alloy shield and a low

density polyethylene jacket.

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

of the soils after exposure for two years.

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

copper.

Coupling specimens of this system to copper had little or no effect on

the corrosion behavior of the copper alloy shield.

System 91 . This system consisted of a 3-mil (0.1 mm) corrugated 1006

low carbon steel outer shield bonded to a 3-mil (0.1 mm) corrugated 4022

aluminum alloy inne-^ shield.

Corrosion of either shield at the jacketed areas was not appreciable

for specimens buried for one year at Site D or two years at Site 3. Severe

corrosion was observed on the outer shield at the window and/or ring areas

of specimens exposed for up to two years at Sites B, C. and E. ELD or near

ELD was noted on the window and ring areas on both shields of specimens

exposed for two years at Site D. The inner and outer shields were at or near

21
ELD at the window and ring areas on specimens exposed for one and two years

at Site E. The specimen at Site A was ELD at all areas examined after one

year of exposure, and the same was observed for the specimen at Site G

after two years of exposure. All three specimens were considered destroyed

at these sites.

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.

Corrosion of varying degrees was noted on the inner aluminum alloy shield

for specimens buried at Site B for two years. The outer shield was at or

near ELD at the window and ring areas for specimens exposed at Site B for

two years and at or near ELD on the inner and outer shield of specimens at

Site E buried for one and two years. The shields of specimens were ELD and

considered destroyed after burial for one year in all three soils and after

two years at Site G.

System 93 . This system consisted of a 3-mil (0.1 mm) corrugated 1006

low carbon steel inner shield bonded to a 3-mil (0.1 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 che 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

at all areas examined, while the inner shield was ELD at all areas except

under the jacket. Corrosion of the inner and outer shield varied from

superficial to moderate at all areas examined after burial for up to two years

at Sites B, C, D, and E.

22
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 specimens exposed for

one and two years at these sites were ELD at all areas examined and were

considered destroyed.

System 95 . This system consisted of a 25-mil (0.6 mm) uncorrugated

seamless aluminum alloy outer shield and a 112-mil (2.8 mm) solid copper

alloy center conductor, with a high density polyethylene jacket.

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

With one exception corrosion was nil or superficial in all of the soils

after exposure for one year. The specimen buried at Site G was ELD at the

un jacketed window and ring areas and experienced severe corrosion at the

area adjacent to the unjacketed window.

System 96 . Same as System 95 except that the shields were coupled to

copper.

Specimens of this system were exposed at Sites 8, D, E, and G only.

Coupling specimens of this system to copper accelerated corrosion of

the shields in all soils buried for one year. In genera!, there was little

or no degradation of the specimen buried at Site B nor was there degradation

at the jacketed areas of specimens at Sites D and E. The unjacketed areas

on specimens buried in Sites D and E were perforated due to pitting cor^’osion

and the specimen exposed at Site G was ELD at all areas examined and was

considered destroyed. The specimen from Site D was exposed without a

wi ndow.

System 97 . Specimens of this system (Table 1) were exposed at Sites

B, D, E, and G only.

23
With one exception, specimens of this system were unaffected by corrosion

during their first year of exposure. The shield of the specimen from Site

G was severely corroded at the unjacketed ring area and near ELD at the

unjacketed window area.

The filling compounds were still tacky.

System 98 . Same as System 97 except that the shields were coupled to

copper.

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

Coupling specimens of this system to copper accelerated corrosion of

the aluminum alloy shield at the window and ring areas in all soils buried

for one year. The specimen exposed at Site E was perforated due to localized

pitting corrosion at the window and ring areas. After burial of one year

at Site G, the shield of the specimen was near ELD at the area adjacent to

the window while the window, ring, and adjacent ring areas were ELD.

The filling compound was still tacky at all areas.

System 99 . Specimens of this system (Table 1) were exposed at Sites

B, D, E, and G only.

Corrosion was nil for specimens buried for one year with the exception

of one. At Site G, the tin-free steel outer shield of the specimen developed

severe corrosion at the unjacketed window area and perforation due to

localized pitting corrosion at the unjacketed ring area.

The filling compound was still tacky.

System 100 . Same as System 99 except that the shields were coupled to

copper.

Specimens of this system were exposed at Sites B, D, E, and G.

Coupling specimens of this system to copper accelerated corrosion of

the tin-free steel outer shields in most sites. After exposure for one

24
year at Sites B, D, and G the un jacketed window and ring areas were perforated

due to corrosion. Ail other areas examined at all sites were unaffected by

corrosion.

The filling compound was still tacky at all areas.

System 101 . Specimens of this system (Table 1) were exposed at Sites

B , D , E , and G.

There was no degradation on the uncorrugated aluminum alloy inner

shield on any of the specimens buried for one year. In general, slight

rust stain was noted on specimens exposed at Site B on the tin-plated steel

outer shield at jacketed and unjacketed seamed areas. The outer shield of

the specimen buried at Site G was perforated by corrosion at all areas

exami ned.

The filling compound was semi -tacky except at corroded areas where it

was dry.

System 102 . Same as System 101 except that the shields were coupled

to copper.

Specimens of this system were exposed at Sites B, 0, E, and G only.

Coupling specimens of this system to copper accelerated corrosion of

the corrugated tin-plated steel outer shield. All areas examined on the

aluminum alloy inner shield were unaffected by corrosion. Degradation of

either shield at Site D was superficial or nil for the first year of exposure.

Severe corrosion was observed at the window and ring areas of the specimens

buried at Site B. The specimen at Site G was ELD at the window area due to

corrosion on the outer jacket, and corrosion at all areas rated on this

specimen was moderate to severe.

The filling compound was still tacky except at corroded areas which

were dry.

25
System 103 . Specimens of this system (Table 1) were exposed at Sites

B, D, and E only. Corrosion of both shields was nil or superficial after

one year of burial in the tnree soils with the exception of one specimen.

The outer shield at the unjacketed window area of the specimen showed slight

localized pitting corrosion after exposure at Site B.

The filling compounds were still tacky.

System 10^ . Specimens of this system (Table 1) were exposed at Sites

B, D, and E only. After an exposure of one year at three sites, the specimen

degradation of the inner and outer shields was nil or superficial with the

exception of one specimen. Slight localized pitting corrosion was noted on the

low carbon steel inner shield at the un jacketed window area for the specimen

recovered from Site E.

The filling compound was still tacky.

System 105 . Specimens of this system (Table 1) were exposed at Sites

B, D, and E only. Specimens buried at all three sites were unaffected by

corrosion after one year of burial.

The tilling compounds were still tacky.

26
SUMMARY AND DISCUSSION

The data presented describes the performance of various cable systems

after exposure for up to six years in different soil environments. Forty-eight

(48) 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 non-copper shield materials. This was done to simulate

field conditions where the shield may be coupled to existing caole systems

having copper shields or to copper ground rods.

Six soil environments were employed which have chemical and physical

properties representati ve of a wide range of soils that may be encountered

in the United States in actual field installations. Some a^'e moderately

corrosive and some are very corrosive toward ferrous anc other metals or

al 1 oys

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.

The performance of Systems 56 and 57 after exposure for six years was

excellent in alkaline soil. Specimens of System 56 buried in Lakewood sand

showed no corrosion after five years of exposure. Specimens o'^' System 56 exposea

for six years were fair in clay soil and coastal sand, while specimens of

System 57 buried in the same soils were poor, as were the specimens exposed in a

tidal marsh. Specimens of Systems 56 and 57 were not installed in Hagersoown loam.

Systems are described in table 1. 27
Specimens of System 58 exposed for five years were good in an alkaline

soil. However, the specimens of System 59 buried for the same amount of

time and in the same soil were poor. Corrosion of System 60 after four

years in coastal sand was very poor and the same was true for specimens

exposed in alkaline soil for five years. Similarly, specimens of System 58

in coastal sand buried for five years and System 61 in alkaline soil were

noted as very poor. After exposure for six years, specimens of Systems 58,

59, 60, and 61 were very poor in clay soil and tidal marsh as were specimens

of Systems 59 and 61 buried for the same time in coastal sand. Specimens

of Systems 58, 59, 60, and 61 were not installed in Hagerstown loam and

Lakewood sand.

After exposure for five years in an alkaline soil, six years in clay

and Lakewood sand, and four to six years in Hagerstown loam, there was

little or no degradation due to corrosion on specimens of Systems 62, 63,

64, 65, and 66. Similarly, there was no degradation on specimens of System

65 after exposure for up to six years in a tidal marsh. The performance of

Systems 62, 63, and 64 exposed in a tidal marsh was, in general, fair.

Specimens of System 66 were not buried in this soil.

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

alkaline soil and four years in Hagerstown loam, clay, and Lakewood sand

were unaffected by corrosion. Specimens of System 70 exposed for three

years in an alkaline soil were poor, while specimens buried in Hagerstown

loam, clay, and Lakewood sand were excellent. Systems 67, 68, 69, and 70

were not installed in coastal sand or tidal marsh.

After exposure for three years in coastal sand, corrosion of System 73

was generally rated as good. Specimens of Systems 73 and 74 (same as

System 73 except coupled to copper) buried in alkaline soil were poor to

28
very poor. Similarly, companion specimens of the same systems exposed for

three years in Hagerstown loam, clay, Lakewood sand, coastal sand, and a

tidal marsh, were poor to very poor.

Specimens of System 75 buried for two years in an alkaline soil and

three years in clay, Lakewood and coastal sand, showed little or no corrosion,

while the specimens exposed in a tidal marsh were poor. System 75 exposed

in Hagerstown loam and System 75 exposed in Lakewood sand were good after

three years of exposure. System 76 (same as System 75 except coupled to

copper) was generally fair to poor in Hagerstown loam, clay, and coastal

sand exposed for three years.

The performance of System 77 exposed for two years in an alkaline soil

was good, while System 78 (same as System 77 except coupled to copper) was

poor to very poor. Specimens of System 77 buried for three years in Hagerstown

loam were fair while specimens of System 78 under the same conditions were

judged to be poor to very poor. Systems 77 and 78 were poor to very poor

in clay soil, Lakewcod sand, coastal sand, and tidal marsh after an exposure

of three years.

Of the soecimens of System 79 exposed for two years in an alkaline

soil and three years in Lakewood sand there was little or no corrosion

observed. System 80 (same as System 79 except coupled to copper) buried

for two years in an alkaline soil was fair, as was System 79 exposed for

three years in coastal sand. The performance of specimens for System 79

buried for three years in Hagerstown loam and clay soil was fair to poor.

The corrosion resistance of System 79 in a tidal marsh was poor to very

poor after three years of exposure. The performance of System 8C in

Hagerstown loam, clay, Lakewood sand, coastal sand, and tidal marsh was

also poor to very poor for the same length of time.

29
There was no corrosion on System 81 buried in alkaline soil for two

years. However, System 82 (same as System 81 except coupled to copper)

exposed in the same soil and for the same length of time was observed as

poor. Specimens of System 81 exposed in Lakewood and coastal sand for

three years were fair. The System 81 specimens buried in Hagerstown loam

and System 82 in Lakewood and coastal sand were in general, poor. System

81 in clay soil and tidal marsh was very poor as were the specimens of

System 82 in Hagerstown loam and clay soil. Specimens of System 82 exposed

in. a tidal marsh for three years were considered destroyed.

Systems 83 and 84 were unaffected by corrosion after being exposed for

two years in an alkaline soil. System 83 remained unaffected after three

years in Hagerstown loam, Lakewood and coastal sand. Specimens of System 84

(same as System 83 except coupled to copper) buried in Lakewood and coastal

sands for three years were good while companion specimens in Hagerstown

loam were noted as fair. Both systems were poor to very poor in clay soil

and tidal marsh after being buried for three years.

Ct‘ the specimens of System 85 exposed in an alkaline soil for two

years, no corrosion was observed. However, System 86 (same as System 85

except coupled to copper) buried in the same soil for the same time was

fair as were the specimens in coastal sand after two years and in Lakewood

sand after three years. Specimens of System 85 in Hagerstown loam and clay

soil were observed as poor after exposure for three years. Severely corroded

specimens of System 86 were found in Hagerstown loam, clay, Lakewood, and

coasual sand buried for three years. Both systems were destroyed due to

exposure after exposure for three years in a tidal marsh.

The corrosion of Systems 87 and 88 buried for two years in an alkaline

soil was moderate as were the specimens of System 87 in Lakewood sand after

30
three years. Coastal sand specimens of System 87 were good, while System 88

(same as System 87 except coupled to copper) was very poor. Corrosion

resistance of both Systems was poor to very poor after being buried for

three years in Hagerstown loam and clay soil. Severe corrosion of Systems

87 and 88 exposed in a tidal marsh was noted and the specimens were considered

destroyed after three years of exposure.

The performance of specimens of Systems 89 and 90 buried in an alkaline

soil for one year and two years in all other soil environments showea

little or no corrosion attack. Systems 91 and 92 in Hagerstown loam and

System 91 in clay soil, Lakewood and coastal sand, were very poor after an

exposure of two years. Specimens of both Systems 91 and 92 were considered

destroyed after exposure in alkaline soil for one year and tidal marsn for

two years. There were no specimens of System 92 installed in clay soil,

Lakewood, or coastal sand.

Specimens of System 93 buried for two years in Hagerstown loam, clay,

Lakewood and coastal sand were observed as generally good. The one year

exposure of System 93 in an alkaline soil was very poor. Spec'-'mens of

System 94 (same as System 93 except coupled to copper) buried in the same

soil for one year and buried in Hagerstown loam for two years were destroyed

due to corrosion. Specimens for System 93 were not installed in a tidal

marsh, nor was System 94 installed in clay soil, Lakewood sand, coasial

sand, and tidal marsh.

Except for Systems 96, 100, and 102, Systems 95 through 105 showed

little or no corrosion in Hagerstown loam, Lakewood and coastal sand after

one year of exposure. In general. Systems 95 through 105 buried in tidal

marsh for one year were noted to be poor to very poor. Corrosion resistance

was fair to good on System 96 in Lakewood and coastal sand. System 100 in

31
Hagerstown loam, coastal sand, and tidal marsh, and System 102 in coastal

sand. Little or no corrosion was observed for specimens of System 96 in

Hagerstown loam and for Systems 100 and 102 in Lakewood sand. The specimens

of System 102 buried in a tidal marsh were very poor, while specimens of

System 96 were destroyed after exposure for one year in the same soil.

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.

56, 58, 60, 61, 73, 77, 79, 81, 85, 87, 91, and S3.

When Systems Mo. 57, 59, 74, 76, 78, 80, 82, 84, 86, 88, 92, 94, 96,

and 102 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 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. 57

and 59. For these specimens, the copper was anodic to the stainless steel

outer shield and cathodic to the inner aluminum shield. With the exception

of one specimen, 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.

32
REFERENCES

[1] G. A. Lohsl and M. Romanoff, "Corrosion Evaluation of Shielding Materials

for Direct Burial Telephone Cables," a paper at the 18th International

Wire and Cable Symposium, Atlantic City, NJ, December 5, 1969.

[2] W. F. Gerhold, J. P. McCann, and W. E. Williamson, "Corrosion of Underground Telephone Cable Shielding Materials in Soil Environments After

Exposure for Four Years," paper presented at NACE Corrosion/74, Chicago,

IL, March 1974.

[3] W. F. Gerhold and J. P. McCann, "Corrosion Evaluation of Underground

Telephone Cable Shielding Materials," paper #31 presented at NACE

Corrosion/76, Houston, TX, March 1976.

[4] W. F. Gerhold and J. L. Fink, "Corrosion Evaluation of Underground

Telephone Cable Shielding Materials," Department of Commerce, NBSIR

81-2243, April 1981.

33
Tables

Table 1 Description of Various Systems Included in the Soil Corrosion

Study of Telephone Cable Shielding Materials

Taole 2 Properties of the Soils at the Test Sites

Table 3 Rating Code for the Corrosion Evaluation of Shields in Cable

Specimens

Table 4 Performance of Shields in Cable Specimens Buried for Up to Six

Years in Sagemoor Sandy Loam (Site A)

Table 5 Performance of Shields in Cable Specimens Buried for Up to Six

Years in Hagerstown Loam (Site B)

Table 6 Performance of Shields in Cable Specimens Buried for Up to Six

Years in Clay Soil (Site C)

Table 7 Performance of Shields in Cable Specimens Buried for Up to Six

Years in Lakewood Sand (Site D)

Table 8 Performance of Shields in Cable Specimens Buried for Up to Six

Years in Coastal Sand (Site E)

Table 3 'Performance of Shields in Cable Specimens Buried for Up to Six

Years in Tidal Marsh (Site G)

34
Figure Captions

Figure 1 Preparation of specimens for cable exposure tests.

Figure 2 System 95 exposed for one year.

Figure 3 System 101 exposed for one year.

Figures 4 & 5 Systems 73, 75, 77, 79, 81, 85, and 87 exposed at

Site A for two years.

Figures 6 & 7 Systems 74, 78, 80, 82, 86, and 88 exposed at Site

for two years.

Figures 8 thru 33 Selected Systems between Systems 73 and 88 exposed

for three years.

Figures 34 & 35 System 56 exposed for six years.

Figures 36 & 37 System 57 exposed for six years.

35
Table 1.

System

56

57

58

59

60

61

62

63

64

65

66

67

68

69

70

Description of Various Systems Included in the Soil Corrosion Study

of Telephone Cable Shielding Materials.

Description

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.

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

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

deposited aluminum on the outer surface.

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

3-

mil (0.03 mm) Type 304 stainless steel with 2-mil (0.05 mm) vapor

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

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

50-pair, 22-gauge air core cable having an 3-mil (0.20 mm)

aluminum alloy shield with a copolymer coating on both sides of

the shield. Cable core was removed.

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

aluminum alloy shield bonded on both sides to a polyolefin polymer.

Shield was bonded to the jacket.

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

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

polyolefin polymer. Shield was bonded to the jacket.

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

aluminum alloy shield bonded on both sides to a polyolefin polymer.

Shield was bonded to the jacket.

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

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.

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.

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.

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.

36
System

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 S-mil (0.20 mm) corrugated aluminum alloy inner shield coated on both sides v/ith 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 'shi el d.

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 on 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 on 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 on 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 on 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 on 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 on both sides with 2-mil (0.05 mm) ethylene

acrylic acid copolymer and an 3-mil (0.20 mm) corrugated aluminum

alloy inner shield coated on both sides with ethylene acrylic acid

copolymer. This was a filled cable with amorphous polypropylene

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

37
Table 1 (continued)

System ; Description

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 on both sides with a 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.

95 25-mil (0.64 mm) uncorrugated seamless aluminum alloy outer shield

and a 112-mil (2.84 mm) solid copper alloy center conductor with

a high density polyethylene jacket.

96 Same as System 95, except that the outer shield was coupled to

copper.

97 25-mil (0.64 mm) uncorrugated seamless aluminum alloy outer shield

and a 112-mil (2.84 mm) solid copper alloy center conductor. This

was a filled cable having a flooding compound of polyisobutylene

between jacket and outer shield, with a high density polyethylene

jacket.

98 Same as System 97, except that the outer shield was coupled to

copper.

38
Table 1 (continued)

System Description

99 25-pair, 22-gauge cable having a 6-mil (0.15 mm) corrugated tin

free steel outer shield, coated on 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 on both sides with a 2-mil

(0105 mm) ethylene acrylic acid copolymer. This was a filled cable

having a clear flooding compound over the core and inne'r shield,

and another type of clear flooding compound over the outer shield.

100 Same as System 99, except that the shields were coupled to copper.

101 6-mil (0.15 mm) corrugated tin plated steel outer shield coated on both sides with a 2-mil (0.05 mm) ethylene acrylic acid copolymer

and a 25-mil (0.64 mm) uncorrugated seamless aluminum alloy inner

shield (outer conductor) having a 98-mil (2.49 mm) solid copper

alloy center conductor with a black polyethylene inner and outer

jacket.

102 Same as System 101, except outer shield was coupled to copper.

103 25-pair, 22-gauge cable having a corrugated aluminum alloy outer

shield bonded to a corrugated low carbon steel inner shield coated

only on the inner shield. This was a filled cable having a clear

flooding compound on the outer and inner shields.

104 25-pair, 22-gauge cable having a corrugated aluminum alloy outer

shield bonded to a corrugated low carbon steel inner shield.

This was a filled cable having a clear flooding compound on the

outer and inner shields.

105 25-pair, 22-gauge cable having a corrugated aluminum alloy outer

shield bonded to a corrugated low carbon steel inner shield coated

on both the outer and inner shields. This was a filled cable having

a clear flooding compound on the outer and inner shields.

39
LO 1 CO 1 rH o 1 rH 1 ro cn z rS 0 Oft u-ft Oft CJ m t CSi 1 0 en cn lT> CSI cn in cn

lo t ^ GO 1 m 0 o 1 lO 1 m 0 to cNJ cn r-e. lO *“

rn 1

fSJ 4-» o 0 1 0 1 m 0

IV o 0 1 ( UO a 0 0 L. wn X c

33 o U r—

O! r— W -*- fn 0 0 0 0 13 S O 1 1 5 u 0 > 0 1 0 0 u W 0) Q Q.

C. c,* ’jtf o «J ro 0 CS3 0 CSJ t- + Z ! 1 IT 1 m Oft I Oft 1 CSi CSi m

c. ^ eft CO w Z ^ csj cn CSJ O

Q.O O*1 ro 1 «T 1 Oft in o s; 1 csi in rsi 0 r*^ cn S3 00 , 0 1 CSJ 0 Of 0 { «T 1 0 •«T m cn

c« 0 0 0

OD <T CO

O 0 0 n 0 uO

P's. IT rH f-H rH

a. CO o m i"S ® Jft IT r-e. r*. PN,

>>

•<“ E > U 0 0 0 0 lT> 0 0 0 0 0 Oft 0 .*« I <T CM <*n 0 m eft _ c in 0 -n x:

3;

C

(n

CS wi

CL* 13 t7) W C 13 eft u C OJ w ^ 4> TO *0

u TOu L. fO *J C 0 0 0 0 0 c U W. -Y-. 0 0 0 0 0 0 0 0 eft 0 0 0. CJ Q. a.a

CO _x c 2 u. :s re • z Z a. «

or c C eft > >» TO TO 0 0 •f— re e 0 0 C cc X 0 0 Cft *J or 3 ?

re C. 03 c -o U CL u Q»

X 0 0 0 03 H- 0 :s E

130 E

>» re "O 0 TO c •3 D re c rr

eft c eft <e eft 5 eft U

S- 0 TO re 0 c E 0 «ft 0 13 E u 5 4.J 03 cv >> 03 eft re cn cn V 13 TO c 13 re re C

Uft »yft “ LJ CJ hsite I

den < 00 0 Q LU 0 oo

cAO

lT> .13 ^ ^ O U

f—* l; •—

(/) «>>

tra

a

</i -o -a

a» q; c W -r- 13 E >

i- ^ o»

a> o 'Oo o ^ e a —

"3 4J I vn «-iO 13 ! o; Q CC H o
Table 3. Rating Code for the Corrosion Evaluation

of Shields in Cable Specimens

Rating Performance Degree of Corrosion

10 Excel 1 ent Unaffected. No indication of corrosion.

9 Excel 1 ent Superficial rust or etching on surface. -

8 Very Good Uniform metal attack, rust, and/or slight localized

pitti ng.

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

or dissipation of metall urgical ly or plastic-bonded

metals leaving cathodic metal intact.

6+ Good Localized pitting; only one perforation in shield

by pitting.

6 Good Localized pitting: two to five perforations in

shield by pitting.

5 Fai r Many localized pits causing perforation of shield;

< 5 percent of shield dissipated by corrosion;

extensive del ami nation of metal 1 urgical ly bonded

metals.

4 Poor Severe corrosion: pitting to perforation of shield;

five to ten percent of shield dissipated by corrosion

severe corrosion of anodic part of metal 1 urgical ly

bonded metals.

3 Poor Severe corrosion: pitting to perforation of shield;

ten to twenty-five percent of shield dissipated by

corrosion.

2 Very Poor Severe corrosion: more than twenty-five percent of

shield dissipated by corrosion; shield still has

electrical continuity along the cable.

1 Very Poor Severe corrosion: shield is close to electrical

discontinuity (ELD) due to perforation in shield and

dissipation of metal by corrosion.

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

corrosi on.

41
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

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 10(5) 10(5) 10(0) 10(5) 10(7)

2 10(5) 10(4) 10(0) 10(5) 10(5) , 3 10(5) 10(5) 10(0) 10(7) 10(7)

4 10(10) 10(10) 10(5) 10(7) 10(7)

5 10(7) 10(7) 10(7) 10(7) 10(7)

59 1 10(0) 10(2) 10(2) 10(0) 10(3) 9

2 10(0) 10(2) 6(10) 10(0) 10(1) 9

sj 9(0) 9(2) 9(0) 10(0) 9(2) 10

4 9(5) 9(4) 9(0) 9(7) 9(5) 9

5 9(5) 10(4) 3(5) 9(3) 9(5) 10

60 1 0(10)5 0(10)5 0(10)0 0(10)5 0(10)3

2 0(10)8 1(10)8 0(10)0 1(10)7 0(10)7

3 0(10)4 1(10)3 0(10)0 0(10)2 0(10)5

4 1(10)5 2(10)7 0(10)0 1(10)7 1(10)7

5 1(10)7 1(10)8 1(10)7 1(10)7 7(10)8

61 1 0(10)1 0(10)0 0(10)1 0(10)3 0(10)5 9

2 1(10)5 1(10)5 0(10)0 0(10)2 0(10)3 10

3 0(10)0 1(10)4 0(5)0 0(10)2 1(10)2 10

4 0(10)5 0(10)4 0(10)1 0(10)5 0(10)5 10

5 0(10)0 0(10)3 0(10)0 0(10)0 0(10)3 9

42
Table 4 (continued)

Exposure

Time Exposed Exposed Under 1/2 Inch 1/2 Inch Copper

SysteiTi (years) Wi ndow Ring Jacket Wi ndow Ring Cathode

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 10

5 10

65 1 10

2 10

3 10

4 10

5 10

66 1 10 10

2 10 9

3 10 Mi ssi ng

4 10 10

5 10 Mi ssi ng

67 1 10

2 10

3 10

68 1 10

2 10

3 10

69 1 10

2 10

3 10

70 1 10

2 10

3 3

43
Table 4 (continued)

Exposure

System

Time

(years)

Exposed

Wi ndow

Exposed

Ri ng

Under

Jacket

1/2 Inch

Wi ndow

1/2 Inch

Ring

Copper

Cathode

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

-1J. 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)

SO 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 X 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 Not recovered

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)

85 1 5(10) 6(10) 10(10) 10(10) 10(10) 10

2 5(10) 5(10) 10(10) 10(10) 10(10) 10

87 1 9(10) 9(10) 10(10) 10(10) 9(10)

2 5(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

44
Table 4 (continued)

System

Exposure

Time

(years)

Exposed

Wi ndow

Exposed

Ring

Under

Jacket

1/2 Inch

Wi ndcw

1/2 Inch

Ri ng

Copper

Cathode

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

45
Table 5. Performance of Shields in Cable Specimens Buried Up to Six

Years in Hagerstown Loam (Site B)

Exposure

Time Exposed Exposed Under 1/2 Inch 1/2 Inch Copper

System (years) Window Ring Jacket Window Ring Cathode

62 1 10

2

- 10

3 10

4 10

63 1 10

2

1 n

3 10

4 10

5 10

6 10

54 1 10

2 10

V./ 10

4 10

65 1 10

0 10

0. 10

4 10

5 10

6 10

66 1 10 10

2 10 10

3 10 10

4 10 Missi ng

5 10 Mi ssi ng

6 10 9

67 1 10

2 Not recovered

3 10

4 10

68 1 10

2 10

3 10

4 10

69 1 10

2 10

3 Not recovered

4 10

46
70

73

74

75

76

77

78

79

80

81

82

Table 5 (continued)

Exposure

Time Exposed Exposed Under 1/2 Inch 1/2 Inch Copp

(years) Wi ndow Ring Jacket Wi ndow Ring Oath

1 10

2 10

3 - 10

10

1 2(10) 2(10) 10(10) 9(10) 9(10)

2 4(10) 3(10) 9(10) 8(10) 8(10)

3 2(10) 1(10) 8(10) 8(10) 8(10)

1 0(10) 1(10) 9(10) 9(10) 5(10) 10

2 3(10) 2(10) 9(10) 8(10) 10(10) 10

3 0(10) 1(10) 8(10) 2(10) 3(10) 9

1 10(10) 10(10) 10(10) 10(10) 10(10)

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

3 6+(10) 6+(10) 10(10) 10(10) 10(10)

1 5(10) 5(10) 10(10) 5(10) 5(10) 10

2 5(10) 5(10) 10(10) 5(10) 10(10) 10

3 3(10) 4(10) 10(10) 5(10) 7(10) 10

1 10(10) 10(10) 10(10) 10(10) 10(10)

2 5(10) 6(10) 10(10) 8(10) 8(10)

3 4(10) 6+(10) 8(10) 8(10) 9(10)

1 2(10) 2(10) 10(10) 9(10) 9(10) 10

2 1(10) 1(10) 10(10) 8(10) 8(10) 10

3 0(10) 0(10) 6(10) 2(10) 2(10) 10

1 6(10) 5(10) 10(10) 10(10) 10(10)

2 5(10) 5(10) 9(10) 8(10) 8(10)

3 4(10) 3(10) 8(10) 8(10) 8(10)

1 2(10) 2(10) 9(10) 9(10) 10(10) 10

2 2(6+) 1(9) 8(9) 8(10) 9(10) 10

3 0(4) 0(4) 5(10) 4(10) 5(10) 10

1 9(10) 5(10) 9(10) 9(10) 9(10)

2 3(10) 4(10) 9(10) 9(10) 9(10)

3 4(10) 9(10) 5(10) 6(10) 6+(10)

1 2(10) 2(10) 9(10) 9(10) 9(10) 9

2 1(10) 1(10) 9(10) 8(10) 8(10) 10

3 1(10) 1(10) 8(10) 2(10) 2(10) 9

47
Table 5 (continued)

Exposure

System

Time

(years)

Exposed

Wi ndow

Exposed

Ring

Under

Jacket

1/2 Inch

Wi ndow

1/2 Inch

Ring

Copper

Cathode

83 1 10(10) 10(10) 10(10) 10(10) lOQO)

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

3 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

3 3(10) 5(10) 10(10) 10(10) 10(10) 9

85 i 9(10) 4(10) 9(10) 4(10) 9(10)

2 6(10) 4(10) 10(10) 8(10) 9(10)

3 4(10) 4(10) 8(10) 8(10) 3(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

3 1(6) 2(6) 9(6) 8(6) 9(6) 10

87 1 5(10) 5(10) 9(10) 8(10) 3(10)

2 4(10) 4(10) 9(10) 8(10) 8(10) , 3 3(10) 3(10) 8(10) 6(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

3 2(10) 0(10) 7(10) 7(10) 7(10) 10

39 i 9 9 9 9 9

2 9 9 9 9 9

90 1 9 9 9 9 9 10

2 9 9 9 9 9 9

91 1 4(5) 3(8) 8(9) 6(9) 7(9)

2 0(9) 3(9) 8(9) 7(9) 3(9)

92 1 Destroyed

2 0(4) 0(3) 7(7) 4(6) 0(5) 10

93 T S(5) 9(7) 9(7) 9(7) 9(7)

2 9(7) 9(7) 9(7) 9(7) 9(7)

94 1 Destroyed 10

2 Destroyed 10

95 1 9 9 10 10 10

95 1 8 8 10 8 8 10

97 1 10 10 10 10 10

48
Table 5 (continued)

Exposure

Time Exposed Exposed Under 1/2 Inch 1/2 Inch Copper

System (years) Wi ndow Ring Jacket Wi ndow Ring Cathode

98 1 8 8 10 10 10 10

99 1 10(10) - 10(10) 10(10) 10(10) 10(10)

100 1 5(10) 6(10) 10(10) 10(10) 10(10) 9

101 1 8(10) 8(10) 8(10) 8(10) 8(10)

102 1 4(10) 4(10) 10(10) 9(10) 9(10) 9

103 1 8 10 10 10 10

104 1 10 10 10 10 10

105 1 10 10 10 10 10

49
Table 6. Performance of Shields in Cable Specimens Buried Up to Six

Years in Clay Soil (Site C)

Exposure

System

Time

(years)

Exposed

Wi ndow

Exposed

Ring

Under

Jacket

1/2 Inch

Wi ndow

1/2 Inch

Ri ng

Copper

Cathode

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) Missi ng

3 10(5) 10(5) 10 10 10 Missi ng

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 10(5) 10(5) 10(4) 10(7) 10(8).

2 10(2) 9(3) 10(4) 10(5) 9(5)

3 9(2) 9(5) 10(0) 10(4) 10(7)

4 9(5) 7(7) 9(1) 9(5) 9(7)

5 3(4) 6+(5) 10(2) 9(5) 6+(5)

6 9(1) 9(0) 9(0) 9(0) 9(1)

59 1 9(3) 10(2) 10(3) 10(5) 10(2) Missi ng

OU 10(1) 10(0) 10(0) 10(0) 10(0) 9

3 10(0) 10(0) 5(0) 10(0) 10(0) 10

‘-r 10(0) 8(0) 5(0) 9(0) 6+(0) Missi ng

5 9(0) 5(0) 10(0) 9(0) 10(0) Missi ng

6 6+(0) 6+(0) 3(0) 6+(0) 6(0) 5

60 1 4(10)7 6(6)6 4(10)1

2 0(10)5 0(10)8 3(10)2

3 1(10)7 2(10)7 0(10)0

4 0(10)7 0(10)3 4(10)1

5 0(10)0 0(10)1 0(10)0

6 0(10)0 0(10)0 0(6)0

5(10)5 5(10)5

7(10)5 2(10)5

2(10)5 2(10)8

2(10)5 3(10)7

0 ( 10)1 0 ( 10)1

0 ( 10)0 0 ( 10)0

61 1 0(10)0 0(10)4 0(10)1 0(10)0 0(10)5 10

2 0(10)0 0(10)0 0(5)0 0(10)0 0(10)0 9

3 0(10)0 0(6+)0 0(6)0 0(5)0 0(6)0 Missi ng

4 0(10)0 0(10)0 0(10)0 0(10)0 0(10)0 6

5 0(5)0 0(9)0 0(6+)0 0(9)0 0(9)0 9

6 0(10)0 0(10)0 0(10)0 0(10)0 0(10)0 3

50
Table 6 (continued)

Exposure

System

Time

(years)

Exposed

Wi ndow

Exposed

Ring

Under

Jacket

1/2 Inch

Wi ndov;

1/2 Inch

Ri ng

Copper

Cathode

62 1 10

2 10

3 10 • 4 10

5 10

6 7

63 1 10

2 10

3 10

4 10

5 10

6 10

64 TX 10

r\L 10

3 10

4 5

5 10

6 7

65' 1 10

2 10

3 10

4 10

5 10

6 10

66 1 10 10

2 10 Missi ng

3 10 Mis si ng

4 10 Mi ssi ng

5 10 Missi ng

6 10

67 1 10

2 10

5 Not rec cvered

4 10

68 1 10

2 10

3 Not recovered

4 10

51
Table 6 (continued)

Exposure

Time Exposed Exposed Under 1/2 Inch 1/2 Inch Cooper

System (years) Wi ndow Ring Jacket Vii ndow Ring Cathode

69 1 10

2 10

3 Not recovered

4 10

70 1 10

2 10

3 10

4 10

73 1 9(10) 2(10) 9(10) 9(10) 5(10)

2 2(10) 2(10) 8(10) 8(10) 8(10)

3 4(10) 2(10) 8(10) 8(10) 8(10)

74 1 1(10) 1(8) 9(10) 3(10) 2(10) 10

2 0(0) 0(3) 9(10) 8(8) 8(10) Missi ng

0(10) 4(10) 9(10) 3(10) 2(10) 10

75 1 10(10) 10(10) 10(10) 10(10) 10(10)

2 8(10) 8(10) 8(10) 8(10) 8(10)

3 10(10) 10(10) 10(10) 9(10) 10(10)

76‘ 1 2(10) 2(10) 10(10) 8(10) 6(10) 10

2 5(10) 4(10) 10(10) 5(10) 5(10) 10

3 4(10) 4(10) 10(10) 7(10) 5(10) 10

77 1 6(10) 10(10) 10(10) 10(10) 10(10)

2 5(10) 4(10) 10(10) 8(10) 8(10)

3 3(10) 3(10) 10(10) 8(10) 5(10)

78 1 2(10) 2(10) 10(10) 9(10) 10(10) 10

2 0(8) 0(4) 8(10) 1(10) 0(10) 10

3 0(0) 0(0) 8(4) 3(5) 1(5) 9

79 1 Not recov ered

2 5(10) 4(10) 10(10) 8(10) 8(10)

3 3(10) 5(10) 9(10) 8(10) 8(10)

80 1 2(5) 2(2) 10(10) 10(10) 10(10) 9

2 0(0) 0(0) 8(8) 8(1) 8(3)

5(1)

10

3 0(0) 0(0) 6+(0) 5(0) g

81 1 9(10) 6+(10) 10(10) 10(10) 10(10)

2 Not recovered

3 4(10) 2(10) 6+(10) 7(10) 8(10)

52
Table 6 (continued)

Sys tem

Exposure

Time Exposed

(years) Window

Exposed

Ri ng

82 1 2(10) 1(5)

2 0(0) 0(1)

3 0(0) 0(0)

83 1 10(10) 10(10)

2 10(10) 6(10)

3 2(7) 5(10)

84 1 6(10) 6(10)

2 5(10) 5(10)

3 2(7) 4(10)

85 1 6+(10) 5(10)

2 6(10) 4(10)

3 4(9) 5(9)

86 1 0(9) 1(0)

2 1(0) 0(0)

3 0(0) 1(0)

87 1 6(10) 5(10)

2 4(10) 3(10)

3 5(10) 2(10)

88 1 2(5) 1(10)

2 1(0) 1(5)

3 0(0) 0(0)

89 1 9 9

2 8 8

90 1 9 9

2 8 8

91 1 0(0) 0(0)

2 1(1) 1(4)

93 1 5(5) 5(5)

2 7(7) 6(6)

Under 1/2 Inch 1/2 Inch Copper

Jacket Wi ndow Ri ng Cathode

10(10) 9(10) 10(10) Missi ng

9(10) 2(8) 4(8) 10

9(0) 2(0) 2(2) 9

10(10) 10(10) 10(10)

10(10) 10(10) 10(10)

10(10) 5(10) 9(10)

10(10) 10(10) 10(10) 10

10(10) 10(10) 10(10) 10

10(10) 4(7) 10(10) 10

9(10) 9(10) 9(10)

10(10) 8(10) 9(10)

10(10) 8(10) 8(10)

9(9) 9(9) 9(9) Missi ng

10(0) 8(0) 10(0). Missi no 8(1) 5(4) 3(0) 10

9(10) 8(10) 8(10)

8(10) 8(10) 8(10)

8(10) 8(10) 8(10)

9(10) 0(10) 9(10) 10

8(10) 8(1) 8(10) 10

7(0) 7(0) 8(0) 0

9 9 9

9 9 9

9 9 9 10

9 9 9 Mi ssi ng

6(6) 6(6) 5(5)

5(5) 7(4) 7(5)

6(6) 5(5) 5(5)

8(7) 8(7) 8(7)

53
Table 7. Performance of Shields in Cable Specimens Buried Up to Six

Years in Lakewood Sand (Site 0)

Exposure

System

Time

(years)

Exposed

Wi ndow

Exposed

Ring

Under

Jacket

1/2 Inch

Ui ndow

1 1/2 Inch Copper

Ring Cathode

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

6 Not recovered

57 1 Not recovered

2 10(5) 10(5) 10 10(5) 10 10

3 10(0) 10(4) 10 10(5) 10(5) Missi no

4 10(6) 10(5) 10 10 10 10

5 10(0) 10(4) 10(5) 10(4) 10(4) 10

6 Not recovered

62 1

j. 10

2 10

3 10

4 8

5 10

6 10

63 1 10

2 10

3 10

4 10

5 10

6 10

54 1 10

2 10

3 10

4 10

5 10

6 10

65 1 10

2 10

3 10

4 10

5 10

6 10

54
Table 7 (continued)

Exposure

Time Exposed Exposed Under 1/2 Inch 1/2 Inch Copper

System (years) Window Ring Jacket Window Ring Cathode

66 1 10 Missi ng

2 10 Mis si ng

3 10 Mi ssi ng

4 10 Missi ng

5 10 10

6 10 Mi ssing

67 1 10

2 Not recovered

3 10

4 10

68 12

3

4

10

10

10

10

69

70

1 Not recovered

2 10

3 Not recovered

4 10

1 10

2 10

3 10

4 10

73 1 9(10) 5(10) 10(10) 9(10) 9(10)

2 8(10) 4(10) 9(10) 8(10) 8(10)

3 8(10) 3(10) 8( 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

3 4(10) 2(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)

10(10)

10(10)

3 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

3 6+ (10) 6+{10) 10(10) 10(10) 10(10) 10

77 1 10(10) 10(10) 10(10) 10(10) 10(10)

2 8(10) 6(10) 10(10) 9(10) 9(10)

3 9(10) 9(10) 10(10) 9(10) 9(10)

55
Table 7 (continued)

Exposure

Tima Exposed Exposed

System (years) Window Ring

78 1 6(10) 5(10)

2 5f 10) 4(10)

3 4(10) 2(10)

79 1 6+(10) 6(10)

C 8(10) 5(10)

8(10) 8(10)

80 1 3(10)

5(10)

6(10)

2 4(10)

3 3(10) 2(10)

81 1X 9(101 9(10)

2 8(10) 5(10)

3 5(10) 4(10)

82 5(10) 5(10)

2 4(10) 2(10)

3 4(10) 2(10)

83 i 10(10) 10(10)

2 10(10) 10(10)

3 10(10) 10(10)

84 11 10(10) 6(10)

2 5(10) 5(10)

3 6(10) 6(10)

85 1 10(10)- 10(10)

2 7(10) 5(10)

3 5(10) 5(10)

86 1 5(10) 5(10)

2 4(10) 4(10)

3 2(3) 2(6+)

87 1 7(10) 7(10)

2 5(10) 5(10)

3 5(10) 5(10)

88 1 6(10) 5(10)

2 2(10)

2(10)

3(10)

3 2(10)

89 i 10 9

2 9 9

Under

Jacket

1/2 Inch

Wi ndow

1/2 Inch

Ri ng

Copper

Cathode

10(10) 10(10) 10(10) 10

10(10) 5(10) 10(10) 10

10(10) 9(10) 7(10) 10

10(10) 10(10) 10(10)

10(10) 9(10) 9(10)

10(10) 9(10) 9(10)

10(10) 10(10) 10(10) 10

10(10) 8(10) 8(10) 10

9(10) 9(10) 8(10) 10

10(10) 10(10) 10(10)

10(10) 10(10) 10(10)

10(10) 9(10) 9(10)

10(10) 10(10) 10(10) 10

8(10) 9(10) 9(10) 10

9(10) 8(10) 9(10) 10

10(10) 10(10) 10(10)

10(10) 10(10) 10(10)

10(10) 10(10) 10(10)

10(10) 10(10) 10(10) 10

10(10) 10(10) 10(10) 10

10(10) 10(10) 10(10) 10

10(10) 10(10) 10(10)

10(10) 10(10) 10(10)

10(10) 9(10) 10(10)

10(10) 10(10) 10(10) 10

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

9(6+) 8(9) 9(8) 10

9(10) 7(10) 8(10)

5(10) 8(10) 8(10)

8(10) 8(10) 8(10)

8(10) 3(10) 8(10) 10

8(10) 8(10) 8(10) 10

7(10) 8(10) 8(10) 9

9 10 10

9 9 9

56
Table 7 (continued)

Exposure

System

Time

(years)

Exposed

Wi ndow

Exposed

Ring

Under

Jacket

1/2 Inch

Wi ndow

1/2 Inch

Ring

Copper

Cathode

90 1 9 9 9 9 10 10

9 9 9 9 9 10

91 1 6(9) 6(9) 9(9) 9(9) 9(9)'

2 1(1) 0(0) 5(5) 6(6) 6(6)

93 1 9(7) 9(7) 9(7) 9(7) 9(7)

2 8(7) 6+(6+) 8(6) 8(7) 8(7)

95 1 9 9 10 10 10

96 1

- 4 9

- 7

97 1 10 10 10 10 10

98 1 8 8 10 10 10 10

99 1 10(10) 10(10) 10(10) 10(10) 10(10)

100 1 10(10) 10(10) 10(10) 10(10) 10(10) 10

101 1 10(10) 10(10) 9(10) 10(10) 10(10)

102 10(10) 10(10) 9(10) 9(10) 9(10) 10

103 1 10 10 10 10 10

104 1 10 10 10 10 10

105 1 10 10 10 10 10

57
Table 8. Performance of Shields in Cable Specimens Buried Up to Six Years in

Coastal Sand (Site E)

System

Exposure

Time

(years)

Exposed

Wi ndow

Exposed

Ring

Under 1/2 Inch

Jacket Window

1/2 Inch

Ring

Copper

Cathode

56 1 10 10 10 10 10

2 10 - 10 10 10 10

3 10(5) 10(5) 10(7) 10(5) 10 (S)

4 10(2) 10 10 10(5) 10

5 Not recovered

6 10(5) 10(3) 10(5) 10(5) 10(5)

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) Missi ng

4 10(4) 10(4) 10(4) 10(4) 10(4) 10

5 Not recovered

6 10(0) 10(0) 10(0) 10(0) 10(0) 9

58 1 10(7) 10(7) 10(7) 10(7) 10(7)

2 10(4) 10(4) 10(2) 10(7) 10(7)

3 10(4) 10(4) 10(5) 10(5) 10(5)

4 10(1) 10(0) 10(1) 10(4) 10(5)

C 10(5) 10(5) 10(0) 10(1) 10(3)

59 1 10(1) 10(2) 10(7) 10(0) 10(7) 10

2 10(0) 10(0) 10(0) 10(0) 10(0) 9

3 10(0) 10(0) 6(0) 9(0) 9(0) 9

4 10(0) 10(0) 10(0) 10(0) 10(0) 9

5 10(0) 10(0) 5(0) 5(0) 10(0) 9

6 10(0) 10(0) 10(0) 10(0) 10(0) 9

60 1 2(10)7 2(10)7 8(10)7 4(10)8 5(10)8

2 0(10)5 0(10)1 0(10)2 2(10)5 5(10)4

3 0(10)5 4(10)7 0(10)4 4(10)5 5(10)8

4 0(10)5 0(10)4 3(10)0 0(10)5 2(10)5

5 Not recovered

61 1 0(10)0 0(10)0 0(10)0 0(10)0 0(10)0 10

2 0(10)1 0(10)0 0(10)0 0(10)0 0(10)0 Mi ssi ng

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

4 0(10)0 0(10)0 0(6)0 0(10)0 0(10)0 Missing

5 0(10)0 0(10)0 0(10)0 0(10)0 0(10)0 10

6 0(10)0 0(10)0 0(6)0 0(6)0 0(9) 10

62 1 10

c 10

3 10

4 8

5 10

6 Not recovered

58
Table 8 (continued)

System

63

64

65

66

73

74

75

76

77

Exposure

Time Exposed Exposed Under 1/2 Inch 1/2 Inch Copper

(years) Window Ring Jacket Window Ring Cathode

1

2

3

4

5

6

10

10

10

10

10

10

1

2

3

4

5

6

10

10

10

10

10

10

1

2

3

4

56

10

10

10

10

10

10

1 10 10

2 10 Miss

3 10 10

4 10 Mi ss

5 10 10

6 10 Mi ss

1 9(10) 9(10) 9(10) 9(10) 9(10)

2 0(10) 5(10) 9(10) 9(10) 9(10)

3 9(10) 8(10) 8(10) 9(10) 9(10)

1 5(10) 2(10) 9(10) 9(10) 9(10) 10

2 4(10) 3(10) 8(10) 8(10) 8(10) 10

3 3(10) 2(10) 9(10) 8(10) 8(10) 10

1 10(10) 10(10) 10(10) 10(10) 10(10)

2 9(10) 9(10) 10(10) 10(10) 10(10)

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

1 5(10) 4(10) 10(10) 2(10) 5(10) 10

2 10(10) 6(10) 10(10) 10(10) 10(10) 10

3 5(10) 3(10) 10(10) 5(10) 5(10) 10

1 6(10) 6(10) 10(10) 10(10) 10(10)

2 10(10) 6(10) 10(10) 9(10) 8(10)

3 5(10) 6(10) 10(10) 8(10) 6(10)

59
Table 8 (continued)

Exposure

System

T ime

(years)

Exposed

Wi ndow

Exposed

Ring

Under

Jacket

1/2 Inch

Wi ndow

1/2 Inch

Ring

Copper

Cathode

7S 1 3(10) 2(10) 10(10) 9(10) 10(4) Missi ng

2 0(10) 2(10) 9(10) 9(10) 8(10) 10

3 2(10) 2(10) 10(10) 5(10) 8(10) 10

70/ ^ 1 9(10) 9(10) 6+(10) 6+(10) 9(10)

Ou 5(10) 6(10) 10(10) 9(10) 10(10)

3 5(10) 5(10) 9(10) 8(10) 6+(10)

80 1 4(10) 4(10) 10(10) 10(10) 10(10) 10

2 2(10) 2(10) 10(10) 9(10) 10(10) 10

3 4(10) 3(10) 6+(10) 8(10) 8(10) 10

81 1 5(10) 9(10) 9(10) 10(10) 9(10)

2 4(10) 5(10) 10(10) 10(10) 10(10)

3 5(10) 5(10) 8(10) 8(10) 6+(10)

S2 -njL 3(10) 3(10) 9(10) 10(10) 9(10) 10

2 2(10) 3(10) 8(10) 9(10) 8(10) 10

3 4(10) 2(10) 8(10) 8(10) 8(10) 10

83 T 10(10) 10(10) 10(10) 10(10) 10(10)

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

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

84 1 10(10) 6(10) 10(10) 4(10) 9(10) 10

2 7(10) 5(10) 10(10) 10(10) 10(10) 10

3 7(5) 6(10) 10(10) 10(10) 7(10) 10

85 1 9(10) 6(10) 10(10) 10(10) 10(10)

2 5(10) 7(10) 10(10) 9(10) 9(10)

3 Not recovered

86 1 5(9) 4(4) 10(9) 9(9) 10(9) 10

2 4(5) 5(1) 10(5) 8(5) 10(3) 10

3 2(6+) 2(4) 8(6) 8(6) 9(6) 10

87 1 7(10) 7(10) 6(10) 9(10) 9(10)

2 8(10) 8(10) 8(10) 8(10) 8(10)

o 6(10) 7(10) 8(10) 8(10) 8(10)

88 TX 5(10) 3(10) 9(10) 8(10) 8(10) 10

2 4(10) 2(10) 8(10) 8(10) 8(10) 10

3 3(10) 2(10) 7(10) 8(10) 8(10) 8

60
Table 3 (continued)

Exposure

System

Time

(years)

Exposed

Wi ndow

Exposed

Ri ng

Under

Jacket

1/2 Inch

Wi ndow

1/2 Inch

Ring

Copper

Cathode

89 1 9 9 9 9 9

2 9 9 9 9 9

90 1 9 9 9 9 9 - 10

2 9 9 9 9 9 Mi ssi ng

91 1 2(2) 0(0) 5(5) 6(6) 6(6)

2 1(1) 1(1) 5(5) 5(5) 5(5)

93 1 8(7) 7(7) 8(7) 6(6) 8(7)

2 6(6) 6(6) 8(7) 6+(6+) 6(6)

95 1 10 10 10 10 10

96 1 6+ 5 8 7 7 10

97 1 10 10 10 10 10

98 1 6 6+ 10 10 10 10

99 1 10(10) 10(10) 10(10) 10(10) 10(10)

IGO 1 6(10) 6+(10) 10(10) 10(10) 10(10) 10

101 1 Not recovered

102 1 7(10) 5(10) 8(10) 8(10) 8(10) 10

103 TX 9 9 10 9 9

1G4 1 8 9 9 9 9

105 1 10 10 10 10 10

61
Table 9. Performance of Shields in Cable Specimens Buried Up to Six Years in

Tidal Marsh (Site G)

Exposure

System

Time

(years)

Exposed

Wi ndow

Exposed

Ring

Under

Jacket

1/2 Inch

'Wi ndow

1/2 Inch

Ring

Copper

Cathode

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) 5(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) Missi ng

4 0 0(4) 0 0 0 Missing

5 0(0) 2(2) 10(0) 10(2) 10(2) Mi ssi ng

6 0(0) 0(0) 5(0) 3(0) 3(0) 3

58 1 6(0) 6(0) 5(0) 5(0) 6(0)

2 9(0) 5(0) 5(0) 6+(0) 5(0)

3 9(0) 9(0) 5(0) 6(0) 6+(0)

4 6(0) 5(0) 5(0) 5(0) 5(0)

5 6(0) 9(0) 8(0) 9(0) 9(0)

6 5(0) 6+(0) 6+(0) 6(0) 9(0)

59 1 9(0) 6+(l) 9(0) 6(0) 10(1) 9

2 6(0) 6(0) 5(0) 5(0) 6(0) 9

3 5(0) 9(0) 5(0) 6(0) 6(0) 9

4 2(0) 6(0) 5(0) 6(0) 0(0) 9

5 6(0) 5(0) 6(0) 6(0) 6(0) 9

6 6(0) 4(0) 5(0) 5(0) 5(0) 0

60 1 0(6)0 2(8)5 1(5)0 0(510 l(6+)7

2 0(10)0 0(6)0 0(5)0 0(9)0 0(6)0

3 0(8)0 0(9)0 0(6)0 0(6)0 0(8)0

4 0(9)0 0(8)0 0(5)0 0(9)0 0(8)0

5 Not recovered

6 0(5)0 0(9)0 0(5)0 0(6)0 0(9)0

61 1 0(5)0 1(8)4 0(5)3 0(510 0(5+)Q 9

2 0(5)0 0(6+)0 0(5)0 0(9)0 0(9)0 9

3 0(6+)0 0(6+)0 0(6)0 0(6)0 0(9)0 9

4 0(4)0 0(6)0 0(5)0 0(8)0 0(9)0 9

5 0(4)0 0(8)0 0(6+)0 0(9)0 0(6)0 9

6 0(6)0 0(8)0 0(5)0 0(6)0 0(5)0 9

62
Table 9 (continued)

System

62

63

64

65

73

74

75

76

77

Exposure

Time Exposed Exposed Under 1/2 Inch 1/2 Inch Copper

(years) Window Ring Jacket Window Ring Cathode

1

2

3

4

5

6

6+

5

10

5

10

7

1

2

3

4

5

6

10

5

10

5

5 10

1

2

3

4

5

6

10

10

10

5

56

1

2

3

4

56

10

10

10

10

10

10

1 9(10) 9(10) 10(10) 9(10) 9(10)

2 0(10) 1(10) 9(10) 8(10) 8(10)

3 0(7) 0(0) 8(10) 0(10) 0(1)

1 0(10) 1(5) 9(9) 9(9) 3(5) 10

2 0(0) 0(0) 8(0) 2(0) 0(0) 10

3 0(0) 0(0) 8(0) 2(0) 0(0) 9

1 10(10) 10(10) 10(10) 10(10) 10(10)

2 1(10) 5(10) 10(10) 5(10) 5(10)

3 5(10) 1(10) 10(10) 8(10) 2(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

3 2(10) 0(10) 0(10) 4(10) 2(10) 10

1 4(10) 1(10) 10(10) 10(10) 10(10)

2 0(10) 0(10) 10(10) 3(10) 0(10)

3 0(0) 0(10) 9(10) 2(5) 0(10)

63
Table 9 (continued)

Exposure

System

Time

(years)

Exposed Exposed

Window Ring

Under

Jacket

1/2 Inch

Wi ndow

1/2 Inch

Ring

Copper

Cathode

73 i 10(2) 10(0) 10(4) 9(0) 10(0) 10

2 0(0) 0(0) 8(4) 8(0) 3(0) 10

3 0(0) 0(0) 6(2) 1(0) 2(0) 9

79 1 5(10) 1(2) 9(10) 9(10) 9(10)

2 1(3) 2(3) 8(10) 8(10) 8(10)

3 0(0) 0(0) 8(0) 5(0) 8(1)

SO 1 0(0) 1(1) 10(10) 6(10) 10(10) 10

2 Destroyed 10

3 Destroyed 9

SI 1 5(10) 5(10) 10(10) 10(10) 10(10)

2 4(10) 5(10) 10(10) 8(10) 10(10)

3 0(0) 0(0) 5(5) 4(2) 4(0)

82 1 1(10) 1(10) 9(10) 9(10) 9(10) 10

2 Destroyed 10

3 Destroyed 9

83 1 2(10) 5(10) 10(10) 10(10) 10(10)

2 5(3) 5(3) 10(10) 8(8) 4(8)

3 1(10) 5(10) 10(10) 5(10) 7(10)

84 1 7(10) 5(6) 10(10) 10(10) 10(10) 9

2 0(10) 0(10) 9(10) 2(10) 2(10) Mi ssi ng

3 0(0) 0(0) 10(0) 3(2) 3(0) 8

85 1 5(10) 4(1) 10(10) 10(10) 10(10)

2 Destroyed

3 Destroyed

86 1 0(0) 0(1) 9(5) 9(3) 9(2) 10

2 Destroyed 10

3 Destroyed G

87 1 6(10) 3(10) 8(10) 8(10) 8(10)

2 0(4) 0(3) 8(5) 8(5) 8(5)

3 Destroyed

OO n 0(0) 0(0) 8(8) 8(4) 8(4) 9

2 Destroyed 9

3 Destroyed 9

89 1 9 9 9 9 9

2 9 9 9 9 9

64
Table 9 (continued)

Exposure

System

Time

(years)

Exposed

Wi ndow

Exposed

Ring

Under

Jacket

1/2 Inch

V/i ndow

1/2 Inch

Ring

Copper

Cathode

90 1 9 9 3 9 9 9

2 9 9 9

Q 9 9

91 1 Destroyed

-

2 Destroyed

92 1 Destroyed

2 Destroyed

95 1 0 0 7

•*> 7

96 1 Destroyed

97 1 1 3 10 10 10

98 1X 0 0 10 2 0 9

99 1 4(10) 6(10) 10(10) 10(10) 10(10)

100 1 5(10) 5(10) 10(10) 10(10) 10(10) - 9

101 1 4(10) 5(10) 6(10) 6(10) 5(10)

102 1 0(10) 4(10) 5(10) 4(10) 5(10) Q

65
PREPg.f?AT10N Or SPEClSiENS

FOR CABLE EXPOSURE TESTS

SPECIMEN 0!MENS!ONS

;?ec:men t'^pe

z

(4

1.5-

A

L-ieruL.. SPECIMEN TYP^ 2 CORE AND INNE.P JACKET

7 :t?‘

—^— SHIELO OVERLAP

~s. '^CCRRUGATEO SH'.ELO

CUTER JACKET

PREPARATION OF SPECIMEN TYPE

^

i| ^\*—c - SEAL BOTH ENDS W1"'H SEAL. NO

COMPOUND A.ND VINYL TAPE \

/

0.5“ RING AROUND

CIRCUMFERENCE OF

A CABLE

N3S IDENTlFiCATION TAG

2"x 0.5 WlMDO'.v

AT SHIELD OVERLAP

0.5“ RING AROUND

CIROUMFERE.NCE OF

PREPARATTCN OF SPECIMEN "'''pr ? I K

2.75"-

Fiaure 1 PreDarat'icn o: = Dec'.Tens GDI a e.xccsure t.asTC
Fiqure 2. Outer Shield; System 95, Sites B,D,E, and 0, left

to right, exposed for one year. Severe corrosion

at the window and ring areas on the specimen from

Site G

Figure 3. Outer Shield; System 101, Sites B,D, and G, top to

bottom, exposed for one year. Dark areas indicate

corrosion at the window and ring areas on the

specimen from Site G.

67
in

Figure 4

Outer Shield; Systems 73,75,77,79,81,85, and 37,

left to right. Exposed at Site A for two years.

Dark areas on specimens indicate corrosion.

Inner Shield; Systems 73,75,77,79,31,35, ana 37,

left to right. Exposed at Site A for two years.

Corrosion was not apoarent.

68
Figure 6. Outer Shield; Systems 74,78,80,32,36, and 88, lef

to right, exposed at Site A for two years. Dark ar

on specimens indicate corrosion. Coupling this system

to copper accelerated corrosion.

Figure Inner Shield; Systems 74,78

to right, exposed at Site A

on System 80 and 32 at the

80,32,86, and 88, left

for two years. Degradation

window and ring areas.

69

(D
Figure 3

Outer Shield; System 73, Sites 3,C,D,E, and 0,

left to riaht, exposed for three years. Specimens

from Sites'^3,C, and S are perforated at the window

and or ring areas.

Figure 9

Inner Shield;

left to right,

degradation of

specimen from S

System 73, Sices 3,C,D,E,

exposed for three years,

the window and ring areas

i t e 0 .

and 0 , Severe

of the

70
Figure 10. Outer Shield;

left to right,

this system to

all specimens.

System 74, S

exposed for

copper accel

i tes B , C , 0 , E , three years,

erated corros

and 0 , C 0 u 0 1 i n g

on on

Figure 11. Inner Shield; Sy

1 eft to right, ex

this system to co

the s p e c i m e n f rom

stem 74, Sites

posed for three

pper accel era te

Site 0

3,C,D,E, and 0,

years. Coupling

d corrosion on

71
1

Figure 12. Outer Shield; System 73, Sites 3,C,D,E, and G,

left to right, exposed for three years. Dark areas

indicate corrosion on the specimens.

Figure 13. Inner Shield; System 75, Sites B,C,D,E, and G,

left to righr, exposed for three years. Corrosion

was not apparent.

72
Figure 14. Outer Shield; System 77, Sites 3,C.D,E, and , left to right, exposed for three years. Severe

corrosion at the window and ring areas of the

specimen from Site G.

Figure 15. Inner Shield; System 77, Sites B,C,D,E, and G,

left to right, exposed for three years. Degradation at the window area of the specimen frcm

Site G

73
Figure 16 . Outer Shield;

left to right,

this system to

the window and

System 78, Sites B,C,D,E, and

exposed for three years. Couplinn

cooper accelerated corrosion at

ring areas on all specimens.

Figure 17. Inner Shield;

left to right,

this system to

Sites C and 0.

System 73, Sites B,C.D.E, and G,

exposed for three years. Coupling

cooper accelerated corrosion at

74
Figure 18 . 0 u ter S hie Id; Sy s t e m / 9, S i tes B, C :.3, E

1 a ft t 0 r i gh t 5 ex po s e d fo r th r e e y e^irs . a r eas i ndi cat e CO rr 0 s i 0 n on s pe c i m ens w

c 0 rros i 0 n on th e sp e c i m en T rom S i t

a G a

a n d r i n g a rea s

, and G

,

Dark

ith severe

t window

Figure 19 Inner Shield;

left to right,

degradation at

specimen from

System 79,

exposed fo

the window

Site G .

S'ites 3,C,D,E,

r three years,

and ring'areas

and G , Severe

on the

75
F i a u r e 20. Outer Shield;

left to right,

this system to

the window and

System SO, Sites B,C,D,E, and G,

exposed for three years. Coupling

copper accelerated corrosion at

ring areas on all specimens.

21 . Inner Shield; System 80, Sites B,C,D,E, and G , left to riaht. exposed for three years. Coup] i ng

this system to copper accelerated degradation a t

the window and ring areas on specimens from

Sites B,C, and G.

76
Figure 22. Outer Shield; System 81, Sites 3,C,D,E, and 6,

left to right, exposed for three years. Dark areas

indicate corrosion on specimens with severe corros

at the window and ring areas on the specimen from

S i t e G .

Figure 23. Inner Shield; System 81, Sites B,C,D,E,

left to right, exposed for three years,

degradation on the specimen from Site G

and G , Severe

i 0 n

77
Figure 2 ^

Outer Shield; System 32, Sites B,C,D,E,and 0,

left to riaht, exposed for three years.Couolino

this system to copoer accelerated corrosion on

the specimens from Sites C and severely.

Figure 25. Inner Shield;

left to right,

this system to

the specimens

System 82, Sites 3,C,D,E, and 0,

exposed for three years. Couolinn

copper accelerated corrosion on

from Sites 3,C, ana

78
Figure 26. Outer Shield; System 85, Sites R,C,D, and G,

left to right, exposed for three years. Dark

areas indicate corrosion on the specimens with

severe corrosion on the specimen from Site G

at the window and ring areas.

Figure 27. Inner Shield; System 85, Sites B,C,D, and G,

left to right, exposed for three years. The

specimen from Site G was severely corroded.

79
F 1 g u r a 28. Outer Shield; System 38, Sites B,C,0,E, and d,

left to right, exposed for three years. CounMnn

this system to copper accelerated corrosion at

most examined areas on all specimens.

Inner Shield; System

left to right, exposed

this system to copper

on most specimens with

the specimen from Site

86 , Sites B,C,D,E,

for three y ears . C

accelerated degrade

50 \/ 0)<'0 deoradaci on

G.

and G , 0 u p 1 i n g

t i on

on

80

Fiaure 29
tA> 0. Outer Shield; System 87, Sites B,C,D,E, and , left to right, exposed for three years. Dark

areas indicate corrosion on specimens with

severe corrosion on the specimens from Sites

C and G

F i g u r e 31. Inner Shield; System 37, Sites B ^ ny r- • ^ — , dOG T,

left to right. exposed for three years . Severe

degradation on the specimen from Site

81

cr

(It
Figure 32. Outer Shield; System 88, Sites B,C,D,E, and 0,

left to right, exposed for three years. Couoling

this system to copper accelerated corrosion

on all s peci mens

Figure 33. Inner Shield; System 38, Sites B,C,D,E, and G,

left to right, exposed for three years. Coupling

this system accelerated degradation on the

specimens from Sites C and G.

82
Figure 34. Outer Shield; System 56, Sites A,C,E,

left to right, exposed for six years,

areas indicate corrosion on specimens

severe corrosion on the specimen from

at the window and ring areas.

and 0 , Dark

w i t h

Site G

Figure 35. Inner Shield; System 56, Sites A,C,E, and G-,

left to right, exposed for six years. Severe

degradation on the specimens from Sites C and G.

83
Figure 36. Outer Shield; System 57, Sites A,C,E, and G,

left to right, exposed for six years. Coupling

this system to cooper accelerated corrosion

on all specimens indicated by dark areas.

Figure 37. Inner Shield; System 57, Si

left to right, exposed for

this system to copper accel

on the specimens from Sites

tes A,C,E, and G,

six years. Coupling

erated degradation

C and G severely.

84
NBS-n4A (REV. 2 «ec) U.S. DEPT. OF COMM.

BIBLIOGRAPHIC DATA

SHEET fSee instructions)

4, TITLE AND SUBTITLE

PUBLICATION OR

REPORT NO.

2. Performing Organ. Report NoJ 3. Publication Date

CORROSION EVALUATION OF UNDERGROUND TELEPHONE CABLE SHIELDING MATERIALS

5. AUTHOR(S)

J. L. Fink, E. Escalante, and W. F. Gerhold

6. PERFORMING ORGANIZATION (If joint or other than MBS, see instructions) 7. Contract/Grant No. 1

NATIONAL BUREAU OF STANDARDS

DEPARTMENT OF COMMERCE

WASHINGTON, D.C. 20234

I

I ^

8.

Type of Reoort & Perioa Covered }

9.

SPONSORING ORGANIZATION NAME AND COMPLETE ADDRESS (Street, City. State. ZIP) 1 Rural Electrification Administration

Department of Agriculture

Washington, D.C. 20250

10.

SUPPLEMENTARY NOTES

I 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. I f document includes a significant

bibliography or literature survey, mention it here)

liorrosion data are 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 metallurgical ly-bonded laminates. Some specimens were exposed bare (uncoatedj, while others nad i Dlastic coatings or other types of coatings on either one or both sides. Metals ! studied included aluminum, copper, low carbon steel, and stainless steel alloys. |

i

i

i

I

12. KEY WORDS (S/x to twelve entries; alphabetical order; capitalize only proper names; and separate key words by semiccicns)

Alloys; corrosion; metal lurgical ly-bonded; metals; plastic-bonded; soils; telephone

cables; underground

13. AVAILABILITY

Unlimited

1

i For Official Distribution. Do Not Release to NTIS

^

i Order From Superintendent of Documents, U.S. Government Printing Office, Washington, D.C.

20402.

Order From National Technical Information Service (NTIS), Springfield, VA. 22161

14. NO. OF

PRINTED PAGES

15. Price

•jSCOmm-DC 6043-O80