TDW PIG-SIG V, Инструкция по эксплуатации и техническому обслуживанию

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Section IV – Pipeline Under Pressure
1.0 Continued
1.3 Tapping the Line
A.
Threaded Valves
: Apply thread sealant to the
external pipe thread of the nipple and thread
tapping valve onto the nipple. The valve must be
rated to at least line pressure, and must have a
minimum through-bore of 2-1/16 inches to permit
passage of the TDW PIG-SIG V plug assembly.
Flanged Valves
: Utilizing a new gasket, install
the valve on the flanged fitting; consider the
orientation of the valve. Keep the fitting-face and
Valve-face parallel. Make sure not to damage the
gasket and that the gasket does not extend into
the bore of the valve.
B. For All Valves : After the valve has been
installed, check the nipple for swaging (distortion)
caused by possible over-tightening of the valve.
This can be done using a THREAD-O-RING
gauging tool if available. Otherwise, insert a
dummy plug without an O-ring through the valve
and into the fitting. If the plug threads into the
fitting, the nipple has not been distorted. If it does
not turn, the fitting is distorted and will not accept
the threads of the PIG-SIG V plug.
⚠ CAUTION
If utilizing a threaded valve, do not
over-tighten the valve during
installation. Over-tightening can
swage the nipple diameter too small
to install the PIG-SIG V plug
assembly.
NOTE :
On all flanges above 500-psi working pressure, use a new
Flex Type, Elastograph, or equal gasket on all connections.
On Ring-Type Joint (RTJ) Flanges, use a new RTJ gasket.