Flowserve McCANNA CryoSeal Ball Valves - Manual (Page 5)

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McCANNA CryoSeal ® Ball Valves FCD MMENIM2007-01-AQ – 04/15
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2.3.2 If necessary, valves may be welded in line without disassembly, however special precautions
must be taken. The valve should be in the open position during welding and remain open until
it cools to ambient temperature. Welding procedures should be followed by qualified personnel
and in accordance with Section IX of ASME Boiler Pressure Vessel Code. The critical tempera-
ture areas (shown in Figure 1) should not exceed 350° F.
a WARNING: Do not attempt any welding on in-line valves under pressure.
2.3.3 When more than one weld is required for each end, the weld passes should alternate from end
to end until the welds are completed.
After the valve has cooled, the bonnet fasteners must be re-torqued to the recommended torque
value (shown in Table 3). When possible, a final seat test should be performed before placing
the valve into service.
2.4 Valves with Vented Cavity Relief:
2.4.1 Install vented valves with the arrow on the body pointed in the direction of normal flow. (Figure 2)
Figure 2. Cavity Relief
Figure 1. Critical Weld Areas
CRITICAL TEMPERATURE AREAS