Parker Hannifin has launched an advanced new range of Viking Lite directional pneumatic control valves that combine high flow rates and fast response in compact, lightweight and robust bodies. The new Viking Lite also features a specially developed valve spool wear-compensating system that minimises friction to reduce both breakaway forces and actuation pressures; it also enables operating life to be dramatically increased by up to 250 per cent, depending on the application.
As a global leader in motion and control technologies, Parker Hannifin already offers an extensive family of pneumatic directional control valves. However, with the launch of the Viking Lite, this family is extended still further, enabling the company to offer new products that enable engineers to increase the performance, reliability and productivity of pneumatics systems without penalties in terms of cost, footprint or weight.
Parker's innovative wear compensating system (WCS) is a key feature of the new Viking Lite directional control valves. The WCS utilises dynamic nitrile bidirectional spool seals that, unlike conventional static or O-ring seals held in a fixed position, are free-floating within specially machined grooves, which effectively form the land areas on the spool. Each seal has a narrow profile so it can easily expand radially when air pressure is applied, creating an extremely efficient seal against the highly polished valve bore. The seal is formed at low pilot pressures, thereby helping to minimise the energy required and ensuring low levels of stiction; in turn, this reduces breakaway forces and improves the speed at which the spool responds to control signals.
This simple but reliable method of construction also means that Viking Lite valves can be used in pneumatic circuits where high cylinder speeds are required, typically up to 1.0m/s, while wear is significantly reduced in comparison with conventional valves, giving a considerable increase in operating life. Although Viking Lite valves do not require lubrication, they can be used in circuits where other components require the use of lubricated air.
To extend the operating life still further, each valve body is manufactured from anodised aluminium, providing excellent resistance to corrosion, with die cast end covers and stainless steel screws. In addition, the combination of integral mounting holes with smooth outer faces prevents dirt or contamination from accumulating, making Viking Lite valves suitable for use in clean applications.
The new Viking Lite valves use direct body porting, are available in G1/8, G1/4 and G3/8 port sizes, and can be supplied for solenoid/solenoid or solenoid/spring operation. Each valve is suitable for use in systems with pressures up to 10bar, and can be used in applications where operating temperatures are typically between -10 and +50degC. Options include a choice of manifolds and pressure bars.