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A Type Pneumatic Actuator

CH-air A Type/PTFE/1 June 2006

Teflon® coated pneumatic actuator

Quick guide to the
CH-air A Type standard features : Robust rack and pinion con- struction
The CH-air A Type actuator is assembled using components machined to fine tolerances to produce a finished product with a very low friction coefficient. This produces an actuator that offers durability and reliability in service. It is compliant with all the usual actuator norms making it com-patible with similarly compliant valves, and position monitoring, control and feedback devices. Careful design in the CH-air A Type spring return models has virtually eliminated the out of balance torques between air and spring strokes so familiar with most of its rivals. This produces a balanced air and spring stroke which creates an equal loading on valve stems. Safety is a key feature, particu-larly in spring return models, where the use of pre-loaded spring capsules which fully relax before the actuator’s end cap is removed, protect engineers when servicing the actuator. Whilst the end of travel can be adjusted in both the fully open and closed positions, the more critical closed position adjust-ment is internal and therefore can not be inadvertently ad- justed by a site operator who may not understand the impor-tance of this adjustment. Attention to details like this have ensured that the CH-air A Type actuators carry the CE mark and have ATEX approval for use in hazardous areas. In all but the smallest and largest actuator sizes, the actuator has dual ISO:5211 drillings and a double square drive, making the mounting of the CH-air A Type actuators flexible and easy. The actuator is of rack and pinion design with an anti blow-out proof pinion, and its ex-truded aluminium body is hard anodized to protect it against oxidization in non-aggressive atmospheres. To cover more aggressive at-mospheres, an electroless nickel-plated version, a Teflon® coated version, and stainless steel versions are available. Repair kits containing replace-ment soft seals and acetal resin sliding parts are available, but with a guarantee of 1 million cycles is offered as standard, on all but the highest cycling appli-cations, the CH-air A Type actuator is almost maintenance High accuracy machining of components ATEX Ex II 2 GD Approved for use in hazardous areas CE Approved Guaranteed for 1,000,000 cycles Balanced air & spring strokes in spring return version Safe to dismantle for routine maintenance Compliant with all actuator standards Accessories are easy to mount

Body protection option –Teflon®

Hard anodised aluminium body
This double coating of 50 microns of hard anodizing and a 15 micron PTFE coating provides superior levels of protection and offers resistance to most aggressive atmospheres. Tests performed on this dual coating showed that salty at-mospheres had no effect on the coating after 1000 hours on a spray test, and 4000 hours in a submersion test. This coating has superseded our former epoxy coating for marine environments. ENP coated option Teflon® coated option Stainless steel version