r^A7:0DJAL BIIE^EAU OF STANDARDS REPORT

KSS PROJECT NBS REPORT

1002“30"10627 January 25, 1962 7^21

FIRE ENDURANCE TEST

of

TWO BULKHEAD ASSEMBLIES

by

J, V. Ryan and E. W. Bender

for

U. S. COAST GUARD

NATIONAL BUREAU OF ST

intended for use within the

to additional evaluation and r listing of this Report, either the Office of the Director, Na

however, by' the Government

to reproduce additional copi(

IMPORTANT NOTICE

irogress accounting documents Approved for public release by the opelllteSe

Director of the National Institute of sion is obtained in writing from Standards and Technology (NIST) permission is not needed,

^ u r, -^a7c prepared If that agency wishes on October 9, 2015.

NBS

FIRE ENDURANCE TEST

of

TWO BULKHEAD ASSEMBLIES

by

J. V. Ryan and E. W. Bender

ABSTRACT

Two bulkhead assemblies were subjected to

a standard fire test. The two differed only

in the density of the asbestos marine boards

used. Each served as an effective barrier to

flame passage for the full 60 minutes of the

test. Excessive temperature rise was reached

on the unexposed surface of the 3^ lb per cu ft

board at 13*9 minutes and on the 36 lb per cu ft

board at l4.5 min.

1. Introduction

At the request of Headquarters, U. S. Coast Guard

(letter of 30 November 1961, MMT, JJ/164. 008/48, JJ/164.008/

49 ), two bulkhead specimens were subjected to fire test in

compliance with Subpart 164.008-3(b) of Specification for

Bulkhead Panels for Merchant Vessels.

2. Specimens

The specimens were submitted by Turners Asbestos

Cement Co., Ltd., Manchester, England. The materials were

delivered to the National Bureau of Standards where they

were assembled under the supervision of a representative of

the submittor. Each specimen, when assembled, consisted of

two pieces of Turnall Asbestos Ships Board with a vertical

joint between, a metal joint member, and metal channel on

the four edges. The edges of the Turnall boards were sanded

to a slight bevel before assembly to prevent binding in the

metal members. The details of the assembly are shown in

Figure 1 at the end of this report.

2

The two specimens differed only as to the densities of

the asbestos marine boards. Enough pieces for two specimens

of each density, 30 and 36 lb per cu ft, were received in

good condition. Measurements made on each piece prior to

assembly indicated the following:

Nominal

Density VJeight Length Width

Mean

Thickness

Actual

Density

Ib/ftb lb in. in. in. lb/ft3

30 22 95 18 .768 28.9

21.5 95 18. 06 .769 28.2

40 9k. 97 30.5 .768 31.1

39 95 30.5 . 765- 30.4

36 27.5 95-03 18. 06 .755 3.^

26 95.06 18. 06 .759 34.5

44.

5

94.88 30.5 .761 344

^3 95 30.56 .757 33.8

The pieces actually used in the test specimens were those

having actual densities (underlined above) nearest the nominal

density.

3. Test Method

The specimens were mounted in two openings of a test frame

arranged to permit the simultaneous fire exposure of three

bulkhead specimens in the wall test furnace. The third opening was closed with an insulated metal panel.

Care was taken that each specimen was restrained against

vertical movement, so that the only relief from thermal expansion

would be that provided for in the design and fabrication of the

specimens* frame and joint details. The periphery between each

specimen and the furnace test frame was sealed with a fillet

of plaster. This plaster fillet covered all the metal on the

fire exposed side except the vertical joint member between the

two pieces of marine board.

- 3

-

Eight thermocouples were placed on the unexposed surface

of each specimen, distributed as shown in Figure 1. Each

thermocouple junction and several inches of its lead wires

were covered by a 6- by 6- by 0.4-in. felted asbestos pad.

Twelve thermocouples, encased in porcelain insulators and

iron pipes, were distributed within the furnace chamber.

The furnace fuel was gas from the local municipal supply.

The fuel flow was adjusted as necessary to produce average

furnace temperatures as close as feasible to those of the

standard time-temperature curve of ASTM E-119? which include:

1000°F at 5 min, 1300°F at 10 min, 1550°F at 3^ min, and

1700°F at 1 hr.

4. Results

The test was conducted on January 10, 1962 and was

witnessed by the following:

W, L. Russon, LCDR, USCG

Ho A. Pledger, Lt, USCG

Paul Gibson, USCG

Graham I. Sleeman, Turners Asbestos Co.

George J. Goll

Willard R.Seipt

No cracks developed through either specimen during the

test, although a diagonal flexure line near the bottom of

the unexposed surface of the 30 ~lb specimen observed at

52 min corresponded to a crack in the exposed surface. The

joint members bowed slightly toward the fire in the first

few minutes but, after about 12 min, the joint members and

marine boards bowed away from the fire. The test was stopped

at 1 hr.

Both specimens remained effective barriers to flame

passage throughout the test, there being no cracks in the

unexposed surface. The limiting 250°F temperature rise at

one thermocouple on the unexposed surface of the asbestos

marine board was reached at 13.9 minutes for the 30 It) per

cu ft board specimen and at l4.5 minutes for the 36 lb per

cu ft board specimen. The fire exposure severity for the

1 hr test was 99»3 percent. Additional temperature data are

given in Figure 1; the condition of the specimens at the

start and at the end of the test are shown in Figures 2, 3?

and 4.

- 4 -

5* Summary

The results of the test indicated that both specimens

served as effective barriers to flame passage for 1 hr, and

that the limiting temperature rise was reached at 13*9 niin

for the particular samples of nominal 3 O 3_b per cu ft Turnall

board and at l4.5 min for the particular samples of nominal

36 lb per cu ft Turnall board used in the specimens.

Neither the contents of this report nor the fact that

the test was made at the National Bureau of Standards shall

be used for advertising or promotional purposes.

TG10230-20;FR 36O8

USCOMM-NBS-DC
^BaBCgaaca.

. . 96»^^V
TEMPERATURE

DATA

AND

CONSTRUCTION

DETAILS

2400 |
• i .

J

r

I
Figure 2. Unexposed surface at start of test.
• \ #

*, "j * /
I tT A!-// f(X>M'N

Figure 3* Unexposed surface at end of test
V.

'}

y 

% $
Figure 4 . Exposed surface about 10 minutes after end of test.
«