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Series GHP High Performance Butterfly Valves
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| Recommended Standards and Specifications |
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| ANSI- |
B16.34
B31.1
B31.3
B16.5 |
Steel Valves
Power piping
Chemical plant/petroleum refinery piping
Steel pipe flanges and flange fittings |
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| MSS- |
SP-55
SP-67
SP-68 |
Quality standard for steel casting
Butterfly valves
High pressure offset disc butterfly valves |
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| API- |
609
598 |
Butterfly valves
Valve inspection and test |
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Seat Design
The Hi-Seat is a true interference seat design and does not rely on line pressure to assist in sealing. All seats seal drop-tight
bi-directionally at low pressure as well as high pressure.
Polymer (PTFE, RTFE) seats incorporate a U-shaped envelope or an O-ring behind the patented dual-lock seat to provide seating energy
and memory.
The memory design allows axial flexibility in both directions of flow as well as allows radial flexibility when the disc is not
fully closed, reducing seat/disc interference, seat wear and stem torque. When the disc closes, the memory design provides circumferential
stiffness and assures the required disc/seat seal tightness.
Seating and Un-seating Torque
Seating and un-seating torques are a function of the size of the valve and the shutoff pressure of the system.
Specific torque ratings can be found in the Seating/Un-seating chart located in the brochure. All torques listed are for normal
service conditions (i.e. operating frequency is a minimum of once per month; disc corrosion is expected to be mild or minor, the
media is a clean gas, liquid or steam, and is non-abrasive) and chemical effects upon the seat are minor.
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