SEALS FOR BUTTERFLY VALVES IN HYDROELECTRIC PLANTS

In hydroelectric plants control valves for the turbine’s water flow are the most commonly used applications. Their regulation is generally realized with butterfly valves whose guarantee excellent results in both terms of water flows blocking and regulating.

Challenge

A primary manufacturer of systems for the hydroelectric industry, tired of the premature wear of the standard seals used in the butterfly valves, asked us to study a sealing solution for a butterfly valve capable of ensuring a long seal even in presence of dirty water.

Solution

Firstly our technical team analyzed the operating conditions of the application and evaluated the customer’s need to maintain the size of the existing seats since it is a refitting and not a new valve project.

TECHNICAL DATA

• Pressure: from 40 to 90 bar
• Fluid: river water with possible contamination of dirt and mud

For this application we have designed a seal with a secondary lip which  allowed us to improve the stability of the seal and guarantee a longer operating life even in the presence of contaminants.

Furthermore, thanks to the use of finite element analysis (FEM), the best sizing of the seal was calculated considering the operating pressures. Our techinicians chose to realize the seals in  SINTEK HTPU, a special polyurethane resistant to hydrolysis with superior mechanical characteristics. SINTEK HTPU allows to obtain greater resistance to tearing.

Refer to our general catalog to find out the recommended materials in ecah operating conditions.