Installation, Operation & Maintenance Manual
20
External-Style Pressure Relief Valve A-1402C Series
4.1.9
RUPTURE DISC
4.1.9.1
These valves include a rupture disc (Figure 4-6) beneath the main valve
assembly. Examine the disc for nicks, damage or any signs of stretching.
Replace the disc if any defects are observed.
4.1.10
RUPTURE DISC FLANGE
4.1.10.1
Look very carefully at the section of the disc flange (Figure 4-7) that is contoured
to hold the disc. No scratches, radial tool marks, nicks, burrs, or corrosion can
be present in the groove or the disc will fail to maintain a pressure-tight seal. If
dents, pits or gouges are observed, do not attempt to remove them by machining.
Discard the flange and obtain a new one.
4.1.10.2
Similarly, on the raised surface on the underside of the valve body flange
(also in contact with the rupture disc) must be completely free of imperfections,
see Figure 4-9.
Examine it carefully. No re-machining is permissible.
Replace the valve body if defects are observed.
Figure 4-6 Rupture Disc
Figure 4-7 Rupture Disc and Disc Flange
Figure 4-8 Spring Guide
Figure 4-9 Underside of Valve Body Flange