GENERAL TORQUE VALUES - Continued
Inch Series Four Bolt Flange Fitting For High-Pressure Service
Clean sealing surfaces (Figure 23, Item 1). Inspect. Scratches, nicks, and burrs cause leaks. Roughness
causes O-ring wear. Out-of-flat causes O-ring extrusion. If imperfection cannot be polished out, replace
Install the O-ring (Figure 23, Item and backup ring, if used) into groove. Use clean oil to hold it in place. Refer
to LO 5-3805-294-13.
Split flange: Loosely assemble split flange (Figure 23, Item 2) halves. Make sure split is centrally located and
perpendicular to port. Hand tighten cap screws to hold flange halves and line in place. Do not pinch O-ring
(Figure 23, Item 3).
Single piece flange (Figure 23, Item 4): Make sure flange is centrally located on port and line is centered in
flange. Install the cap screws. Hand tighten cap screws to hold flange and line in place. Do not pinch O-ring.
After components are properly positioned and cap screws are hand tightened, tighten one cap screw and then
the diagonally opposite cap screw. Tighten the two remaining cap screws. Tighten all cap screws as specified
in the table.
Inch Series Four Bolt Flange Fitting for High-Pressure Service.
Inch Series Four Bolt Flange Fitting for High-Pressure Service Torque Values.
Min - Max Torque
Cap Screw Size a - inch
Nominal Flange Size - inch