Vacuum Catalogue - Edwards

Valves for Vacuum Systems5Page168Complete RangeWhatever the application, Edwards has the right solution to meet yourprocess requirements. Well known for its innovation in pump design,Edwards applies the same energy and commitment to its valves. Theresult is an extensive range of valves, with a choice of actuationmethods, materials and size. Materials of construction have beenuncompromisingly selected for performance in high vacuum.Confidence in Edwards valves begins early in the design process. Weuse techniques such as Finite Element Analysis to optimise thedesign of the valve. An arduous testing program in our environmentaltesting laboratory prior to release to production ensures that everyvalve we supply will meet the needs of your application. Once inproduction, all valves are subject to stringent quality control and areindividually tested with a helium mass spectrometer leak detector.Bellows sealed pipeline valves are manufactured with 100% greasefree O-rings exposed to vacuum delivering unrivalled lowcontamination levels.Selection GuideWhen you design a vacuum system, your choice of valves will bedetermined by the need for certain operating parameters. When youchoose a valve for your vacuum system, consider all of theparameters listed in the left hand column of the table as describedbelow.Actuation The choice is manual, solenoid or pneumatic, which will bedetermined by your system design and what facilities are available tothe machine.Dirty System Tolerance Vacuum valves have a differing ability toremain leak tight in "dirty" vacuum systems. If your system generatesor contains dust or other particulates, choose a valve with a hightolerance.Size Choose a valve which complements the size of your vacuumpipeline. To maintain high pumping speeds and throughputs, do notreduce the size of your pipeline to accommodate a smaller valve.Pressure Range Both the maximum and minimum pressure ratingare important, particularly if the vacuum system is occasionallypressurized to above atmospheric pressure.Port Configuration Depending on the location of the valve, you mayneed either an in-line or a right angle valve.Life The mean time to failure is important for solenoid and pneumaticvalves in rapid cycle duties, or where you have extendedmaintenance intervals.Position Indication You may need local or remote indication of valveposition as part of your control system.Closure Speed Use either a solenoid valve or pneumatic valve if youmust have rapid valve closure.Corrosion Resistance Valves are available in stainless steel forthose applications that process corrosive gases.Shop online at www.edwardsvacuum.com