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Installation, Operation & Maintenance Manual
18
External-Style Pressure Relief Valve A-1402C Series
4.1.5 PLUG
4.1.5.1
The sealing surface is the plug seat (Figure 4-4) Clean the plug with the emery paper (400 grit) then wipe it clean
with a cloth and a suitable solvent. Run your fingernail over the seat surface to detect any flaws.
4.1.6 SEALING SURFACE (VALVE MOUNTING)
4.1.6.1
The underside of the rupture disc flange is the surface that seals to the mounting plate on the railcar (Figure 4-5).
Machining of this surface is permitted. A good seating surface is necessary to ensure there are no leaks in this area.
NOTE:
Repair work is limited to cleaning and polishing. See Paragraph A4.11.1 of the Tank Car Specifications.
NOTE:
Please refer to paragraph A4.11.2 of the Tank Car Specifications and consult Appendix E for dimensions
and applicable tolerances.
NOTE
NOTE
WARNING: Machining Not Allowed.
Machining, grinding, welding or other alterations to the valve seat or
plug seat is not allowed per AAR M1002, Paragraph A4.11 of the Tank Car Specifications.
WARNING
Figure 4-5 Machinable Surfaces (Tongue Flange)