Stonkus Hydraulic


Valve Actuators | Control Valves | Vacuum Primers | Accumulators | Relief Valves

Valve Actuators

Valves used in Parco systems are fitted with a specially designed cylinder actuator. The Parco Cabletorque Operator was developed in the 1950's and has evolved into a very efficient, durable, and time tested actuator. The cylinder is of the double rod design and is rigidly supported. The mounting configuration eliminates side loading and rod/piston seal problems associated with lever style and single rod actuators. The double rod design provides constant parallel thrust. Unlike a single rod cylinder, the Parco Cabletorque Operator applies equal torque to the valve during open and close cycles.

Actuators are available in single and tandem cylinder designs. The vast majority of operators utilize hydraulic cylinders engineered and built in house, a no compromise design with heads, pistons and glands cast in brass. Cylinder barrels are machined and honed stainless steel, oversized rods are hard chrome plated stainless steel. The design is simple and easy to maintain.

Cylinders are available in a wide variety of bore & stroke combinations and pressure classes. Air, oil, and water can be used as operation media.

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Control Valves

Parco systems are built primarily for quarter turn AWWA spec. valves in sizes ranging from 3" through 96". Most common valve types are Ball, Butterfly, Cone, and Plug. Specialty valves are also available for aggressive fluids, solids handling, high pressure and high velocity applications. Valves are carefully selected for each application with materials of construction that are appropriate for the intended service.

Vacuum Primers

Parco Priming Systems are used primarily to lift a column of fluid and provide flooded suction for non self-priming pumps. A vacuum is created in a tank by means of a reciprocating vacuum pump or pumps (in a duplex system) which is hard piped through a priming valve to the suction header and to the highest point of each pump casing. As vacuum is applied in the suction header, the water level rises to a point above the pump where it closes the priming valve and insures a positive air free prime.

Our pre-engineered, skid mounted packages are easily and quickly installed. Connections to the suction line and three phase power connections are all that are required. Duplex systems provide two reciprocating vacuum pumps mounted to an ASME code vacuum tank. All necessary vacuum and float switches are pre-wired to a tank mounted control panel housing all the necessary controls, indicating lights and switches.

Made in the USA, Parco Priming Systems are engineered and built in house and are offered in six standard sizes from 49 to 1,000+ cubic feet. Triplex and special application primers are also available.

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Parco Depend-A-Power Hydraulic Accumulators and Hydropneumatic Systems are used to store oil or water under pressure, providing usable operating fluid for Parco Control Valve Systems in applications where a clean source of operating fluid in a sufficient quantity and pressure are unavailable (finished water pump stations, sewage lift stations, stormwater pump stations) and in applications where valve operation is critical during a power failure.

Depend-A-Power Systems are pre-engineered, skid mounted packages that are easily and quickly installed. Connections to the supply line, return line, and 3 phase power connections are all that are required. Duplex systems provide two oil pumps and two air compressors mounted to a frame, an integral sump tank supports an ASME code pressure vessel. All necessary pressure and float switches are pre-wired to a tank mounted control panel housing all the necessary controls, indicating lights and switches.

Parco Accumulators are offered in low to medium pressure classes (100-1,300psi) with capacities from 10 to 1,000+ gallons. Many choices of fluids are available including water, standard petroleum based hydraulic oil, food grade fluid, and aviation fluid for low pressure (under 300psi) applications. Phosphate ester and water glycol are fire safe fluids and are recommended for use above 300 psi.

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Relief Valves

Parco Angle Pattern Relief Valves are designed for severe applications in surge relief and surge anticipation service for clean water systems. The ANRV is of the differential piston design utilizing a metal-to-metal seat allowing velocities to 100 ft./sec. High capacity pilot valves allow quick valve opening with smooth, controlled closure.

Valve body style is angle pattern. Body and piston construction is cast iron, ductile iron, or brass. Flanging is available in ANSI #125, or #250. Valves are available in sizes from 3" to 12". Capacities from 2,500 to 39,000 GPM, and heads to 400'.

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