Flowserve 1878 Swing Check Valves with Pressure Seal - Manual (Page 3)

1878 Swing Check Valves with Pressure Seals FCD ADENIM0007-00
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1.0 PHYSICAL DESCRIPTION AND OPERATION OF EQUIPMENT
1.1 Swing Check Valve
The swing check valve is designed for use in a system where protection against reversal of flow in the line is desired.
The force of the upstream fluid swings the disc out of the waterway, allowing the fluid to pass through the valve with
minimal pressure drop. However, should the direction of flow completely reverse, the disc weight will cause the disc to
swing into the waterway and, along with the force of the reversed flow, force it to seal against the seat.
A dual seat may be supplied which provides a hard surface for high differential pressure sealing and a resilient seat for
sealing during low differential pressure.
2.0 Design Conditions
Refer to the applicable drawing in Section 13 of this manual.
3.0 Operating Conditions
Refer to the applicable drawing in Section 13 of this manual.
4.0 Test Conditions
4.1 Each valve covered by this manual has received the following hydrostatic tests:
4.1.1 Shell hydrostatic test at 1.5 times the 100
°
F pressure rating.
4.1.2 A seat leakage and disc closure test at 110% of the 100
°
F pressure rating.
5.0 Operating Precautions And Limitations
5.1 Maximum hydrostatic test pressure shall not exceed the values imposed by the ASME Code, Section III.