Interlock safeguards diaphragm valves

Usually located in wash-down areas, these small valves commonly control the flow of high purity water in closed loop systems. Because of the valves’ small size, conventional stainless steel interlocks are usually too big and heavy.

To solve this problem, Smith Flow Control has developed a new interlock for use with diaphragm valves in hygiene-critical applications.

The interlock uses a simple, rotational Ellis lock mechanism that is suitable for small valves due to its compact design. It has an Acetal plastic body, which is lightweight and well suited for use with small diaphragm valves. It is also said to be highly resistant to moisture, solvents and many other neutral chemicals. Despite this, it is tough, hardwearing and has a high resistance to repeated impacts. The Ellis key has a spring-loaded rubber seal, preventing water ingress during washdown or sterilisation procedures. 

"Smith Flow Control is renowned for its heavy duty mechanical interlocks for the oil and gas industries, but this new lock design demonstrates our ability to provide interlocks for specialist applications, such as small diaphragm locks," Dan Kelly, the company’s North American general manager, said.