- The Necessity of Fluid Control

The control of fluid dynamics in process systems is essential to ensure efficient and safe use of pumping systems. Uncontrolled fluid in motion can physically destroy a pumping system, including the pump, piping, valves, meters, back pressure valves, rupture disks and other in-line instrumentation and equipment.

A pump puts fluid in motion by adding energy to it. This kinetic energy, observed as pressure, is carried in the fluid and slowly lost into the piping system through friction. When the fluid in motion is quickly stopped or started, the kinetic energy is released in the form of a pressure spike. This occurs because fluids are not compressible and, therefore, transfer rather than absorb the shock of the sudden pressure change. This "water hammer" effect is similar to a hammer hitting a concrete wall. Some energy goes into the wall, a little is lost to friction, but most goes back into the arm, vibrating the hammer out of the hand.

Positive displacement pumps and quick closing valves both start and stop fluids that are in motion. Positive displacement pumps derive their pumping action by capturing a given amount of fluid in a chamber and pushing it out the pumpís discharge. Each pump cycle includes a suction stroke during which fluid flow is stopped. The stroke rate of a pump can reach into the hundreds and even into the thousands per minute. This pumping action produces an acceleration/deceleration of the fluid, creating units of uncontrolled energy, resulting in PULSATION, observed as pressure spikes.

Quick closing valves start and stop large volumes of fluid in motion. The velocity, the volume, and the density of the fluid all add to the pressure spike created when the valve is shut and kinetic energy is released. Without any type of cushion to absorb the energy, a high pressure SURGE is created, traveling up to the speed of sound. This hydraulic shock travels as a compression wave back and forth through the entire pipe system until it is finally dissipated by friction or a system component fails.

Not Just An Accessory ... A Necessity
The solution to the problems associated with fluid dynamics is found in Blacoh Fluid Control's line of SENTRY pulsation dampeners, surge suppressors, suction stabilizers, thermal expansion chambers, and auxiliary energy storage chambers. SENTRY controls the fluid energy by minimizing these pressure spikes and producing a smooth and even flow.