Compact actuator delivers high torque with low air consumption
August 2002
Valves, Actuators & Pump Control
The compact pneumatic quarter turn actuator, supplied by Dupleix Liquid Meters (DLM), has been developed to be simple, reliable, and efficient using a patented rack and pinion design. Four separate racks, each with its own piston, develop torque around the centrally located pinion.
This four-piston design permits air pressure to be applied to four racks simultaneously, significantly increasing torque, and thus reducing the actuator's overall size compared to single and double piston designs.
Symmetrically spaced at 90° angles around the central pinion, the Compact's four piston/racks also achieve a more uniform load distribution than do single and double rack actuators, greatly reducing gear wear at the points of contact between rack and pinion.
A look at the operation of the Compact actuator reveals several other important advantages of its symmetrical four piston design, including a trouble-free high cycle life, minimum air consumption, energy efficiency, fast response, and of course, a compact size.
The corrosion resistant, anodised coating of the body, covers and stop provides protection internally and externally, and a two-layer external polyurethane paint coating provides protection against aggressive environments. The stop design allows rotational adjustment in both directions of actuator travel. The 'Safe Guard' design ensures secure operation, assembly and disassembly of the actuator.
Compact's superiority over single and double rack designs is achieved through distribution of the total torque equally among its four piston and racks, so that each rack generates less torque. At a given air pressure, Compact can produce the same torque output using smaller diameter pistons and a narrower pinion. Four small cylinders, each located on one side of a cube, results in a compact, space saving shape.
Four pistons result in a shorter piston travel, which is what is responsible for Compact's fast acting operation. The device's cube shape and short piston travel minimise dead space. Dead space is space not swept by piston travel that must be pressurised before piston motion begins. This is pressurised air that does no work but nonetheless requires energy to maintain pressure. This minimum dead space geometry is what results in minimum air consumption, which in turn means improved energy efficiency, since little pressurised air goes to waste.
For more information: Marc von Ruben, DLM, 011 457 0500, [email protected], www.dlm.co.za
Further reading:
Alfa Laval expands hygienic valve portfolio
Valves, Actuators & Pump Control
Alfa Laval is expanding its hygienic valve portfolio by introducing the Unique SSV pressure relief valve and the Leakage Detection butterfly valve, alongside new smaller sizes of the Unique Mixproof CIP and Unique Mixproof process valves.
Read more...
Preparing pump systems for adverse weather conditions
Valves, Actuators & Pump Control
As the severity of storms in South Africa increases, so has the rush of sediment-laden water become a major issue and a significant challenge for irrigation. When sediment levels rise to just 10 grams per litre or more, the risk of pump wear and dam silting increases dramatically.
Read more...
High-flow solenoid valve
Emerson Automation Solutions
Valves, Actuators & Pump Control
Emerson has introduced the new ASCO Series 327C solenoid valve, which features a direct-acting, high-flow design that provides superior flow-to-power ratio. It permits high flows at minimum power levels, making it ideal for use in power plants, refineries, and chemical processing facilities.
Read more...
Proportional cartridge valve series is the fastest in its class
Valves, Actuators & Pump Control
Parker Hannifin is introducing the enhanced version of the proportional cartridge throttle valve series, TFP. The new pilot valve further reduces the step response times by up to 30%, making the TFP the fastest valve in its class.
Read more...
Proportional cartridge valve series is the fastest in its class
Valves, Actuators & Pump Control
Parker Hannifin is introducing the enhanced version of the proportional cartridge throttle valve series, TFP. The new pilot valve further reduces the step response times by up to 30%, making the TFP the fastest valve in its class.
Read more...
Inspection system for leak detection in valves in hazardous areas
Extech Safety Systems
Valves, Actuators & Pump Control
Leaking valves in industrial plants not only lead to loss, safety risks and possible contamination and pollution, but also result in high economic costs. Therefore, valves in hazardous areas require regular proper inspection and preventive maintenance to ensure their functionality.
Read more...
Control head for automation of hygienic process valves
Burkert South Africa
Valves, Actuators & Pump Control
Burkert’s Type 8681 control head is optimised for decentralised automation of hygienic process valves. Thanks to its universal adapter, it can be combined with all normal commercial butterfly valves, ball valves and single- and double-seated valves.
Read more...
Hydroformed tube valve body
Burkert South Africa
Valves, Actuators & Pump Control
One of the most common necessities for manufacturing pharmaceuticals, cosmetics, food and beverages are diaphragm valves. What used to be a dull two-way race between forged and cast body variants is now being challenged by an exciting, ground-breaking technology. The hydroformed, light-weight diaphragm tube valve body will change the way you think about plant design and operation.
Read more...
Global pumping giant ready to support hydrogen economy
Valves, Actuators & Pump Control
With abundant sunshine and wind, southern Africa is perfectly positioned to become a global powerhouse in green hydrogen production. Two key projects are already in advanced stages of development in Namibia. KSB has identified the vast potential of these types of projects in southern Africa, and through its KSB Pumps and Valves subsidiaries in Namibia and South Africa is investing heavily in bringing the right skills to the region.
Read more...
Compact valve position indicator
Emerson Automation Solutions
Valves, Actuators & Pump Control
Emerson’s new TopWorx DVR Switchbox is an entry-level addition to the DV Series of valve position indicators. It combines a durable resin enclosure, compact size, and a patented cam design that provides a reliable valve position feedback for water and wastewater systems, food and beverage production lines, and industrial utilities.
Read more...
printer friendly version