4.8.25 Oxygen regulator purge. The regulator inlet shall be connected
to a regulated source of oxygen (see 4.7.2). With the supply valve in the "on"
position, the diluter toggle in the 100 percent position, and the emergency
pressure control in the emergency position, apply the required pressure
(see 4.7.5) to the inlet and allow the regulator to flow freely for five minutes
The regulator shall conform to the requirements of 3.6.24.
Do not perform this test on test stand models
62A-116-E1, 1172AS100, or 1316AS100.
4.8.26 Oxygen bomb (2000 psi regulators only). Nonmetallic parts
and the regulator shall be subjected to oxygen bomb tests to determine
compatibility of the items with high pressure oxygen.
126.96.36.199 Equipment. The equipment used in performing these tests shall
be in accordance with Figures 1 and 2. The main valve shall be a rapid-
opening 1/4 inch valve~ shall require no internal lubrication for operation,
and shall be rated for at least 3,000 psi operation. The valve shall be leak
tight when closed and shall open with such rapidity that at least 95 percent
of the total pressure rise shall have occured within the test chamber in
20 7 mlliseconds. The pressure rise time may be determined by measurement
with a fast-responding small volume pressure transducer substituted for the
test chamber in the test setup. The tubing and fitting connecting the valve
to the test chamber shall be 3/16 inch size and shall be fabricated from
corrosion-resistant steel. The run of tubing between the valve and the test
chamber shall not be bent more than 4 degrees. The bleed valve shall be of
a type which uses no organic material to accomplish its seal and requires
no interior lubrication for operation. The bleed valve shall be installed
so that when it is closed the test chamber does not communicate with the
packing side of the valve. Test samples 3/16 inch diameter by 0.75 inch thick,
shall be made from three of the test slabs submitted for qualification before
the test slab is exposed to the ozone-resistance test.
188.8.131.52 Procedure (elastomeric material). Each elastomer sample
used in the high pressure portion of the regulator shall be subjected to the
following procedure: A sample shall be inserted in the corrosion-resistant
steel recess of the test chamber and the test chamber assembled. The quick-
acting valve shall be fully opened, and the test chamber pressurized with
oxygen at 2175 25 psig for 30 seconds. At the end of the 30 second
period, the pressure in the test chamber shall be released by means of the
bleed valve, the test chamber opened and the sample shall be visually
examined. If there is no indication of ignition, the pressurizing operation
shall be repeated at 60-second intervals. The pressurizing operations shall be
repeated until either ignition occurs, or until three pressurizing operations
have been performed. Remove the sample from the test chamber; the sample
shall not show any evidence of charring or deterioration. With a fresh sample,
the series of three pressurizing operations shall be repeated. This procedure
shall be continued until either a sample has ignited, or until five test
samples have been tested. The test material shall pass the requirements
specified in 3.6.25.