Switch and Valve Concepts Used in Fluid Power

Pneumatic valves used in fluid power
(ASCO Numatics)

The direction in which a cylinder piston will move or a fluid motor will rotate can be controlled by the direction of flow into the device. A cylinder is said to reciprocate if it's piston travels back and forth being reversed automatically at each end of its stroke without human operator attention. In an air cylinder, automatic reciprocation can be stopped by an electrical action or by a shutoff valve in the airline. If stopped by electrical action it will continue to travel until it reaches one end or the other of its stroke. If stopped by shutting off the air, it can be made to stop anywhere in its stroke.

Cylinders and Actuators
(ASCO Numatics)

Fluid valves are typically described as being either in the open or closed position. As described, the open position allows the flow of fluid, while the closed position prevents flow. The normal position of the valve is defined as the position of the valve when its spool is unshifted and the power is off. This means that any mechanical actuators, such as springs, are in their non-actuated positions. Electrical actuators, such as solenoids, are powered off. 

The normal position can sometimes be referred to as the unshifted, de-energized, or unactivated position. Valves that do not have mechanical or electrical actuators do not have a normal position because they must be manually moved. When shifted they remain in that state until manually shifted to another position. The terms normally opened and normally closed are used to describe the condition of a valve when it is in the normal position.

Watch the video below for a better understanding of these concepts.

For more information on fluid power components, or on fluid systems, contact Process Control Solutions by visiting https://processcontrolsolutions.com or calling (800) 462-5769.

Fluid Power Applications in Water and Wastewater Treatment Plants

In plants all across the Midwest, ASCO Numatics solenoid valves, cylinders, manifolds, and other fluid automation devices provide ultra-reliable service in water and wastewater treatment facilities. ASCO Numatics has a well-earned, 50 year reputation as a key supplier for OEMs, engineering contractors, valve assemblers, and end users seeking dependable treatment of potable water and wastewater.


Some of the most common applications to use ASCO Numatics products are:

• Air Preparation
• Aeration and Odor Control
• Bio Refinery Solutions
• Carrier Water Control
• Disinfection and Filtration
• Process Valve Piloting
• Seal Water Control
• Solids Dewatering

For additional information on water and wastewater treatment applications, read the document below. For assistance with any ASCO Numatics requirement, contact Process Control Solutions by calling (800) 462-5769 or visiting https://fluidpower.processcontrolsolutions.com.

ASCP Numatics Water Wastewater Application Brief from Process Control Solutions, LLC

Numatics 503 Series Solenoid Pilot Actuated Valves

​The Numatics 503 Valve series provides higher flow and higher reliability in one versatile valve platform. The 503 Series is available in dual 3-Way and 4-Way solenoid air pilot actuated valves. They are available with manifold or individual base mountings, proprietary or ISO 15407. Numatics 503 series valves are compatible with the Numatics G3 Fieldbus Electronics Platform.

Standard Numatics 503 Series Valve Specifications:

• Cv 1.0 – 1.4
• Port Sizes: ¼, 3/8, 8mm, 10mm, Push-In, NPTF & G Tap
• 5 ported, 2X3-Way, 2 and 3 position, 4 Way, spool & sleeve & rubber seal
• Operating Pressure Range: 28" HG. Vacuum to 115 PSIG/ Vacuum to 8 Bar
• Pilot Pressure Range 29 to 115 PSIG / 2 to 8 Bar
• Temperature Range(Ambient): -14 °F to +115 °F/ - 10°C to 50 °C
• Numatics 503 Series Valve Features
• G3 Electronics Compatible
• Solenoid air pilot actuated
• Low wattage, 1.7 watt for DC application
• DC solenoids polarity insensitive with surg suppression
• Plug together circuit boards eliminate internal wiring
• Integral recessed gaskets
• Push-in Fittings to accommodate various tubing sizes
• Simple conversion from internal to external pilot
• IP 65 Certified

Numatics Offers Express Products Program

Numatics, Inc. is a leading manufacturer of pneumatic products and motion control products. Since 1945, Numatics has emerged as the prominent specialist in developing and manufacturing pneumatic and fluid power components for a widely diverse field of automated industry.

Numatics Express Shipping Program guarantees product shipment in two, three or five business days. Unlike most traditional quick ship programs, the Numatics Express Shipping Program includes the most comprehensive offering in the industry.

Check out the Numatics Express Catalog below. For any applications questions or ordering requirement, visit Process Control Solutions at this link, or call (800) 462-5769.

Numatics Express Catalog: Pneumatic and Motion Control Products from Process Control Solutions