Detailed Introduction

Water hammer relief valves are used to reduce pressure fluctuations in pipeline systems caused by pump start-up, shutdown, or power outages during pump stoppage, providing reliable protection for pumps and pumping stations. This valve is a pilot-operated, hydraulically actuated piston control valve, specifically available in angle-type and straight-through configurations. The pressure differential across the water hammer relief valve serves as the driving force for its opening and closing. The drive mechanism comprises two control chambers: an upper chamber controlled by pilot valves, operated by adjusting the high-pressure and low-pressure pilot valves, and a lower chamber vented to atmosphere through a fixed orifice, providing cushioning during valve closure.

Sudden pump shutdowns in pipelines typically generate significant pressure fluctuations. In water supply systems with long pipelines, these pressure fluctuations often manifest as pronounced low-pressure segments followed by sudden high-pressure surges. The low-pressure pilot valve detects this initial pressure drop and opens itself, thereby activating the main valve to prevent high-pressure surges from returning through the system. The opened main valve vents the subsequent high-pressure surge to the atmosphere. The high-pressure pilot valve detects the same high-pressure surge and opens, keeping the main valve open to discharge excess energy. When system pressure returns to the high-pressure pilot valve's set point, the pilot valve itself closes, causing the main valve to shut off. This stabilizes system pressure between the predetermined high and low pressure limits.

Features

1. Maintains precise and consistent pressure stability. Upon overpressure or pressure dropping below the set value, it fully opens to promptly drain and relieve pressure.

2. Adjustable closing speed eliminates pressure fluctuations during valve closure.

3. It can be installed in any position, allowing for maintenance and inspection without altering pressure settings or removing it from the pipeline.

4. The protective pressure can be freely set according to on-site conditions, making commissioning convenient.

5. Long service life, featuring a unique anti-cavitation valve seat design with all internal components manufactured from stainless steel.

6. Install filtration devices in control pipelines to reduce the risk of blockage.

7. Replaceable elastic sealing ring ensures tight valve closure.

8. Equipped with a visual rod that displays the piston's operating position.

9. Air cushion cushioning: The air chamber beneath the piston shoulder provides cushioning during valve closure.

10. Differential Piston Design: Even under extremely low operating pressures, the unique differential piston design delivers reliable operating force, ensuring automatic valve closure when pressure returns to normal levels.

11. Cavitation Resistance: Since water hammer prevention valves typically discharge directly into the atmosphere, high-velocity water flow and cavitation often occur during operation. The valve's unique seat design (V-shaped opening) not only protects the seat from cavitation damage but also prevents impact from high-velocity discharge flows.

Pressure: PN16

Valve Body: QT450

Valve Core: SS304

Valve Seat: SS304

Medium: Water

Temperature: ≤120°C

Model Selection Recommendations