Flowserve TSQVIOM Durco Mach 1 Severe Service Valve IOM - Manual (Page 3)

3
SECTION I
INSTALLATION INSTRUCTIONS – FLANGED AND WELDED
TSQV PLUG VALVES
FLANGED:
Installation of Flowserve flanged valves is best accomplished by locating valves in
pipeline flanges, assuring all corrosion and foreign materials are removed from pipe
flange, and then centering the gaskets with the valve flanges. Fasteners or taper
pins should be used to align holes and locate gaskets. Fasteners should be
tightened to the corresponding valve and fastener value.
WELDING:
Flowserve Corporation, Flow Control Division recommends using only qualified
welding procedures and personnel for weld installation of TSQV valves.
The following precautions should be observed:
1. The valve should be inspected prior to welding to assure that no foreign materials
obstruct the flow passageway and that the weld preparation area is free of corrosion
and physical damage.
2. The valve should be in the open position while being welded. Open position is
when the flats on the plug stem are parallel with the pipeline.
3. The TSQV valve contains various sleeve and diaphragm materials that have
different maximum temperature limitations. Refer to Table 1.1 for temperature
limitations.
4. The valve body sleeve and diaphragm area must not exceed these temperatures
during welding. This includes preheats, interpasses or post weld heat treatments, as
applicable. Refer to Figure 2 for locations of the sleeve and diaphragm in the center
valve section
5. Welding of the TSQV Valve without disassembly may be accomplished with no
damage to the sleeve and diaphragm. Precautions MUST be taken to cool the valve
bowl and monitor temperature. The temperature of the center or bowl area of the
valve must not exceed the listed temperature of the material. Valves, sizes two inch
and smaller, must be wrapped with water soaked, fire-resistant material to cool the
valve bowl and inlet where the weld is to be made. Use temperature melt crayons
equal to the sleeve and diaphragm rating to mark the body welding end and monitor
the body temperature. Thermocouples may be attached to the welding end of the
body or surface pyrometers may be used to monitor the body bowl temperature.
CAUTION: DO NOT ALLOW WATER
FROM THE SOAKED WRAPPING
MATERIAL TO ENTER THE
WELDMENT.
Table 1.1 – Temperature Limitations
Material
Description
Max.
Temperature
UHMWPE 200°F (93°C)
PFA 500°F (260°C)
FEP and Tefzel 275°F (135°C)