Page 23 - InertexCatalog2010

OPRA® Small ID Noted as the PW or Pipe Wall Style:
All OPRA® element of the OPRA® PW gasket is positioned as close as possible to the flange ID. The ID of OPRA® PW
gaskets range from 1/8” larger than the nominal pipe size (NPS ½” – NPS 3) to ¼” larger than the nominal pipe size (NPS
4 – NPS 8) to 3/8” larger then the nominal pipe size (NPS 10 – NPS 24).
1) The width of the sealing area ranges from ½” wide for NPS ½ - NPS 3, 5/8” wide for NPS 4 – NPS 8 and ¾” wide
for NPS 10 – NPS 24.
2) Instead of having a standard bolt hole pattern, OPRA® PW gaskets have a slot for each bolt. The OD of the slot
aligns the gasket correctly on the flange. Replacing the standard bolt hole with a slot is another means of
reducing the gasket contact area.
3) OPRA® PW gaskets are our standard design for standard pipe flanges
OPRA® Large ID Noted as the BC or Bolt Circle Style:
1) The sealing area of the OPRA® BC gasket is positioned as close as possible to the inside edge of the bolt holes.
2) The width of the sealing area is ½” for all OPRA® BC gasket sizes.
3) OPRA® BC gaskets are a design option that can be used with non-standard gaskets – specifically large diameter
vessel gaskets.
Selection:
1) OPRA® PW design is the standard for pipe flanges; however, the OPRA® BC pipe flange gaskets are available if
necessary.
2) OPRA® gaskets can be custom designed for any non-standard piping or vessel flange. Information required for
design is: Vessel Flange ID, OD, and BCD. Number of bolts, diameter of bolt, assembly torque recommended
and flange profile (smooth, grooved, serrated, etc).