ADC 150-1122-03, Руководство пользователя

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Appendix B - Technical Reference 150-454-111-06
28 February 25, 2000 HRE-454
Vented-to-Pressurized Conversion Procedure
The following instructions are for converting the HRE-454 gel-filled vented enclosures to external pressurized
enclosures.
The HRE-454 enclosure can be converted to a pressurized housing that uses a continuous, local, air pressure
source. The conversion requires replacing the breather vent valve with an optional pressure relief valve. The
breather vent valve, located in the base pan, allows the internal pressure to equalize with the outside pressure. The
optional pressure relief valve, included in the shipping kit, replaces the breather vent valve and prevents over-
pressurization when pressurized from the external air source. The HRE-454 comes with a gel-filled cable, which
precludes pressurizing through the cable stub.
Use the following instructions, along with Figure 2 on page 5 , to convert the HRE-454 enclosure from a vented
housing to a pressurized one:
1 Locate the breather vent valve on the bottom of the housing (see Figure 4 on page 7 ). It is a metal valve
located on the far side away from the cable stub inlet.
2 Remove the valve by unscrewing it in a counterclockwise direction.
3 Save the vent or store it inside the housing for future conversions.
4 Check the threaded hole for debris and clean it, if necessary.
5 Remove the pressure relief valve from the plastic bag. Verify that an O-ring is installed on the threaded end
of the valve.
6 Carefully place the threaded end of the pressure relief valve into the threaded brass fitting from which the
breather vent valve was removed.
7 Hold the valve straight and push it into the hole. Turn the valve clockwise to screw it in place.
8 Handtighten the valve until it is secure against the gasket material.
The housing is now ready to be pressurized through either the Schrader air stem valve, which accepts a standard
tire valve chuck, or the air intake stem of the T-valve, as shown in
Figure 2 on page 5 and Figure 4 on page 7 . A
desiccant bag is also included in the HRE-454 along with the pressure relief valve. Remove this bag and place it
in the HRE-454 prior to pressurization.
1 Attach a plastic tube,
1
/
4
-inch (.64 cm) inner diameter (ID) by
3
/
8
-inch(.83 cm) outer diameter (OD), from the
external air source to the
1
/
4
-inch (.64 cm) air intake protrusion of the T-valve. (The plastic tube is not
included.)
2 Secure the tube to the valve with the hex bolt and ferrule.
The maximum pressure for an air-filled enclosure is 12 PSI.
Static pressurization requires monitoring and maintenance as the pressure decreases over
time.
If there are any signs of resistance while screwing the valve into place, you could be
crossthreading the part. Remove the valve and restart.