Bypass pipes, accompanied by a three-way control valve, are often seen in hydronic systems at both served loads (e.g., reheat coils) as well as at primary equipment (e.g., cooling towers). Reasons for ...

In August’s column, I discussed three-way control valves, their associated bypass pipes, and the importance of a balancing valve being located within the bypass pipe. Such balancing valves are needed ...

Compressible fluid flow through control valves will inevitably cause some form of flow-induced vibration in the fluid system. Identifying the type and cause of the vibration requires detective work.

Learning the basics can ease loop tuning frustration and ensure stability. During plant operations, it seems that tuning control loops is an ongoing task, which can be a continual frustration to ...

In process flow control, there are many factors affecting variability, but the greatest contributor is the control valve’s performance. Issues associated with control valves, such as dead band, ...

In a typical chilled water hydronic system, fluid is moved through the piping network by pumps and controlled by a series of balancing and control valves. Distributed pumping is more than just ...

Choked flow in control valves is a subject of serious concern for industrial users. The term is usually associated with destructive process conditions that can damage valve internals or expose ...

Feedwater control valves play a critical role in boiler operation. One important parameter of their design is the pressure drop at the rated condition as well as off-design conditions. However, ...