MIL-D-0010132 Discs, Valve

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MIL-D-0010132K(EA)

3.3.1.3 Tensile set. The average tensile set shall not exceed 15 percent

when specimens are stretched 600 percent, held for 10 minutes, released, and

rested-for 10 minutes when tested as specified in 4.4.4.1(c).

3.3.1.4 Durometer hardness. The average Type A Shore Durometer hardness

shall be 40 � 5 for the type III disk when tested as specified in 4.4.4. l(d).

Aged (oven process).

3.3.2

3.3.2.1 Tensile strength and ultimate elongation. After aging in accordance

with 4.4.4.l(b), the average tensile strength and average ultimate elongation

of the test slab shall increase or decrease no more than 20 percent of actual

values obtained in 3.3.1.1 and 3.3.1.2 when tested as specified in 4.4.4.1(c)

The tensile strength shall not be less than 17.9 megapascals.

3.3.2.2 Disk characteristics. After aging in accordance with 4.4.4.l(b),

the disks shall exhibit no tackiness or increased hardness. The disks shall

not tear when tested as specified in 4.4.4.2(a).

3.3.3 Resistance to oxygen -pressure aging. Disks shall show no cracking or

increased hardness or tackiness after 72 hours of accelerated aging in oxygen,

at a pressure of 2.10 � 0.10 megapascals and a temperature of 70� + l�C, when

tested as specified in 4.4.4.3.

3.4 Resistance to airflow. When the outlet valve Is clean, thoroughly dry,

and properly assembled to the outlet valve seat as shown on Drawing D5-2-606

(Seat. C15 Outlet Valve), D5-81-3 (C29R1 Voicemitter-Outlet Valve), or

E5-81-125 (C29R5 Voicemitter-Outlet Valve Assembly), whichever is applicable,

the resistance to airflow through the assembled outlet valve less valve seat

housing assembly (Drawing D5-81-134) shall not exceed 22 millimeters of water

at an airflow of 85 liters per minute when tested as specified in 4.4.4.2(b).

When testing the complete 0C29R5 voicemitter assembly, resistance to airflow

shall not exceed 30 millimeters of water at an airflow of 85 liters per minute

when tested as specified in 4.4.4.2(b).

3.5 Leakage. When the outlet valve disk is thoroughly dry and properly

assembled to the outlet valve seat as show on Drawing D5-2-606 (Seat, C15 Out-

let Valve), D5-81-3 (C29R1 Voicemitter-Outlet Valve), or ES-81-125 (C29R5 Voice-

mitter-Outlet Valve Assembly), whichever is applicable, the leakage through the

assembled outlet valve shall not exceed 15 milliliters of air per minute at a

pressure drop of 1.0 inch of water when tested as specified in 4.4.4.2(c).

3.6 Preproduction. Prior to the start of regular production and followlng

any change in regular production methods or rubber formulation, a preproduction

sample of disks and test slabs shall be produced in accordance with this speci-

fication for examination and test (see 4.3).