GB/T 35149-2017 in English

GB/T 35149—2017 Interpretation of the Standard for Piston Balanced Pump Control Valve

1. Overview of the Standard

This standard specifies in detail the terms and definitions, structural forms, model compilation, material requirements and test methods of piston balanced pump control valves. Applicable to valves with nominal sizes of DN50~DN400 and nominal pressures of PN10, PN16 and PN25.

2. Explanation of key terms

Balanced: A structural form that uses medium pressure to balance the force of the valve disc to reduce the axial force during opening and closing. Piston balanced pump control valve: A piston-driven valve with cut-off and check functions, suitable for starting water pumps and preventing water hammer damage.

3. Structure and model

4. Material requirements

Valve body: Ductile iron (QT500-7), austenitic stainless steel (CF8). Valve shaft: Martensitic stainless steel (20Cr13, 30Cr13). Seal ring: Rubber (NR), styrene-butadiene rubber (SBR).

5. Technical requirements

6. Test methods and inspection rules

Shell strength: Withstand 1.5 times the nominal pressure and no leakage for 5 minutes.
Sealing performance: Withstand 1.1 times the nominal pressure and no leakage for 5 minutes.

7. Action performance

Opening time: 2s~120s,
Closing time: 75%~85% of the fast stage, the rest of the slow stage.

Implementation suggestions

In actual applications, the appropriate model should be selected according to the needs of the water pump system, and the sealing and action performance should be checked regularly to ensure long-term stable operation.