Surge Control

Surge control is used to prevent pressure surges, which can occur in a hydraulic system when the flow in a pipeline is stopped too quickly. When a valve closes or a pump stops the water or oil or other fluid in a hydraulic system will attempt to continue flowing. This will cause an increase in pressure which can damage the pipe. Surge control devices absorb and limit this pressure increase and prevent damage to the pipework.

What is hydraulic surge
Hydraulic pressure (transient flow) occurs when the flow of fluid in a pipeline is abruptly changed. Piping systems that use quick acting valves, or use pumps that start up or shut down rapidly, are susceptible to pressure transients (surges). These conditions can result in piping failure, damage to pumps, fittings, instrumentation, and other system components.
Controlling hydraulic surge
Controlling hydraulic surges can increase the life of hydraulic systems by effectively managing these destructive forces. Fast acting surge relief valves, Surge suppressors, bladder surge tanks, and hydropneumatic device (surge tank) can be used to control surges.

Typical applications
Surge control products are currently protecting fluid systems in numerous industries and defense industries, including airport refueling systems, bulk marine loading/unloading facilities, hydrocarbon pipeline system, fire systems (as surge tanks), municipal water and sewage pump systems, petro-chemical facilities, cogeneration plants, mobile fuel trucks, and diesel fuel loading

Surge Relief Valves
Surge Relief Valves are used in most applications including marine loading/unloading application, liquid pipeline transfer systems, fire protection and water pumping stations. They utilize a differential pressure valve to control pressure transients. A surge relief valve for a liquid transporting pipeline, comprising a surge relief line adapted to be tapped from the main transportation pipeline. The relief line includes the surge relief valve which is conditioned to open very quickly to substantial flow when the pressure in the line exceeds a predetermined safe limit, which is well above the normal pipeline pressure. When the surge relief valve opens very quickly, it diverts to a reservoir called the surge relief tank (Floating roof, slop tank, closed tank etc.), that quantity of liquid which is necessary to prevent the pressure from exceeding said predetermined limit. Hence, in the event of the surge, much of the pressure is absorbed in the liquid and pipe, and just that quantity of liquid which is necessary to relieve pressures of unsafe proportions is discharged to the surge relief tank. A return line can be employed to evacuate the reservoir to the main pipeline when the surge subsides.

Hydropneumatic surge tanks for water, waste water, and sewage service
Water, waste water, and sewage pumping applications, incorporate a hydraulically designed nozzle to dampen destructive energy and prevent vortexing.