INSTALLATION


METAL TO METAL SEATED VALVES

 Perform installation welding in accordance with ASME Boiler and Pressure Vessel Code, Sec. I, Part PW, or ANSI B31.1 Para 127.

   IMPORTANT:

A.  DO NOT DISASSEMBLE VALVE. Valve must be assembled and tightly closed during welding to protect seat from heat distortion and weld splatter.
B.  Allow 1/16" gap between bottom of socket, or butt weld end, and end of pipe (PW 41.5.7, or ANSI B31.1 Para 127.3.3).
C.  Preheat per Table 1.

TABLE 1
PREHEAT AND POSTWELD HEAT TREAT REQUIREMENTS

P-1
SA-105
P-5
SA-182 GR. F22
P-8
SA-182 GR. F316
PREHEAT
50° F
(A100.4.1)*
PREHEAT
400° F
(A100.4.4)*
PREHEAT
NONE REQUIRED
(A100.4.7)*
POST WELD HEAT TREAT
NONE REQUIRED
(PW-39)
POST WELD HEAT TREAT
REQUIRED WHEN NOMINAL
WALL THICKNESS EXCEEDS 5/8"
(PW-39)
LOCALIZED ONLY PER (PW-39-4-2)
POST WELD HEAT TREAT
NONE REQUIRED
(PW-39)
* ASME BOILER AND PRESSURE VESSEL CODE, SECTION I, PART PW-38



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