Control Valve Cavitation Solutions

Cavitation is the formation of vapor spaces (bubbles) in the control valve cavity resulting from a rapid change in pressure. When the bubbles move downstream and are exposed to a larger cross-sectional area, velocity decreases and pressure increases, the surrounding higher pressure causes the lower pressure bubble to implode, which causes shockwaves. These shockwaves can cause metal fatigue and cause excessive wear on the internals of the valve. As the bubbles collapse, they make a discernible sound with accompanying vibration, and the damage to a valve can happen quickly (weeks or months).

Cavitation is very destructive and may wear out the trim and body parts of the valve in a short time. Using hard internal materials provides a slight improvement but costs more.

Flowserve Valtek Cavitation Solution Control Valves prevent cavitation damage and minimize hydrodynamic noise even under the most severe liquid applications. Their unique, patented designs eliminate cavitation damage and provide straightforward maintenance and a long life even with demanding applications. 

For more information about Flowserve Valtek Control Valves in Florida, contact Instrument Specialties by calling +1 407.324.7800  or visiting https://isisales.com.

Combating Cavitation in Industrial Process Control Valves

Cavitation in liquid processes produces bubbles which can
damage valves.

In process control valves, cavitation results from a rapid drop in pressure as liquid passes through the valve. It results in the formation of vapor spaces or bubbles within the valve cavity. When the bubbles move downstream into a larger cross-sectional area, velocity decreases and pressure increases. The higher pressure now surrounding the bubbles causes them to implode, producing shockwaves which propagate through the liquid. These shockwaves can cause metal fatigue and excessive wear on the internals of the valve. The collapsing bubbles also make a discernible sound with accompanying vibration. The cumulative effects of cavitation can cause rapid deterioration of a valve, resulting in reduced control function, frequent need for service, or premature failure.

There are ways to mitigate cavitation. Some involve changes in the process, others, incorporating a properly designed and selected valve with trim that reduces or prevents the conditions that cause cavitation. The paper below, authored by Flowserve, provides an in depth examination of the causes of cavitation, then continues with explanation of how their specialty valves are designed to overcome the conditions that promote it.

There are detailed illustrations showing the specific valve trim features that impede cavitation. Share your process control valve challenges with application experts, combining your process knowledge with their product application expertise to develop effective solutions.

Cavitation Control in Industrial Valves from Instrument Specialties, Inc.