Product Overview

It is used for effective isolation during cross-connections between urban water supply pipe networks and various user pipe networks, or between domestic drinking water and heterogeneous water systems such as reclaimed water, fire-fighting water, air-conditioning water, and greening water. It is also used for supporting installation of non-negative pressure equipment, and can strictly prevent the occurrence of backflow pollution.

Main Features

• Threaded connection for quick, easy installation and disassembly.
• Dual-check valve structure to block backflow and prevent pollution.
• Good pressure resistance for stable work without easy leakage.
• High-quality corrosion-resistant internal parts for long service life.
• Compact structure, small size, suitable for narrow spaces and easy maintenance.

Working Principle

The working principle of the LHS711X threaded backflow preventer is to use two check valves in series to form a pressure isolation zone. When the system pressure is normal, the check valves open to allow water to flow forward; if backflow risk occurs (e.g., downstream pressure exceeds upstream pressure), the check valves close immediately, and the drain valve in the isolation zone opens to release pressure, thereby preventing water backflow.

Structural Features

• A threaded connection design for easy installation and disassembly with pipeline systems.
• Two series-connected check valves as the core components to block reverse water flow.
• A built-in pressure isolation zone between the two check valves, equipped with a drain valve for pressure relief during backflow risks.
• A compact overall structure that adapts to common pipeline installation spaces.

Maintenance

• Check hydraulic oil level annually
• Test closing time every 6 months
• Inspect disc and seat for wear during system shutdowns
• Lubricate adjustment mechanism yearly
• Verify proper operation after system pressure changes