Butterfly Valve With Bypass

This product is derived from the double eccentric butterfly valve of our company. It also has superior performance and security. Plus the bypass system’s unique advantages, it’s more and more popular with the clients around the world.

It consists of the main valve，the integral bypass pipe and bypass valve.

When closing the valve, close the main valve first and then the bypass valve; When opening the valve, first open the bypass valve, then the main valve. In this way, to balance the differential pressure between upstream and downstream, and the main butterfly valve can be opened and closed easily.

Valve Body

The bodies are constructed of ductile cast iron, with double flange ends in accordance with EN1092-2(other standard drilling be provided as special request)

Valve Disc

The flow through disc design is employed to minimize line turbulence and lower head loss. The greater free flow area provides less pressure drop in the full-open position than other disc shapes. The material of ductile iron and stainless steel are available.

The internal and external coating(FBE) in 250μm DFT is corrosion and abrasion resistant, suitable for use for drink water, treated wastewater, raw water etc.

The valves have position indicator and have adjustable end limit stops at both open and closed end position to prevent damage by excessive operating force. They shall close clockwise. For underground valves, the position indicator will be extended above ground.

The gearbox operator is worm wheel type, and has self-locking function. If necessary, the spurgear/bevelgear is equipped with to reduce the required input torque.

All the valves are designed for no leakage under flow from either direction tested at a differential pressure across the seal of rated working pressure. Each valve is subject to a body strength and seat leakage test of separately 1.5 times and 1.1 times the design pressure according to EN12266 before leaving workshop. Test certificate is to be submitted.