NON RETURN VALVE is automatic in operation and designed to prevent reversal of flow in fluid piping systems. The valves are maintained open by the flow of fluid in the forward direction and are closed by the back pressure of the fluid or by the weight of the closing mechanism or a spring force. Various designs are available as listed below.
The range of non-return valve size from 50MM to massive units of 600MM Dia. The swing check variation is low-pressure drop unit based on a hinged disc. This type of valve is suitable for low-velocity applications with infrequent velocity reversals. The valve can be fitted with external weights to allow the faster closure to reduce water hammer or shock pressure on flow reversal. External systems can also be included to force the valve closed in the event of a local fire.
MATERIAL OF CONSTRUCTION
|
No. |
PART NAME |
MATERIAL |
SPECIFICATION |
|
1. |
BODY |
CAST IRON |
IS:210 GR. FG-200 |
|
2. |
DISC WITH HINGE |
||
|
3. |
COVER |
||
|
4. |
BODY SEAT RING |
L. T. BRONZE |
IS : 318 GR LTB-2 |
|
5. |
DISC FACING RING |
||
|
6. |
HINGE PIN |
STAINLESS STEEL |
AISI-410 |
|
7. |
BOLTS / STUDS |
CARBON STEEL |
IS: 1363 CL-4.6 |
|
8. |
NUTS |
IS : 1363 CL -4.0 |
|
|
9. |
GASKET |
RUBBER |
IS 638 TYPE (B) |
|
10. |
AIR RELEASE PLUG |
M.S GLVD |
|
|
11. |
SIDE PLUG |
HYD. TEST PRESSURE
|
RATING |
BODY |
SEAT |
|
PN-1.0 |
15 kg/ cm2 |
10 Kg / cm2 |
|
PN-1.6 |
24 Kg / cm2 |
16 Kg / cm2 |
|
DURATION |
5min |
2 min |
MATERIAL SPECIFICATIONS
