Aerospace
Aircraft emergency landing gear blowdown system control valve
Space rated manual fill and drain valve
matic pressure to the aircraft main brakes and parking brake in the absence of hydraulic pressure . Rotary valves also enable the flight crew to manually pressurise multiple APUs by diverting manually pumped air or nitrogen gas to one of several on-board APUs . In rotorcraft , a manual valve might be used to inflate the Emergency Floatation Systems ( EFS ) which keep the craft afloat in the event of an unplanned water landing . Manual multi-turn valves are also used as proportional devices to preset the control of flow in a system . These valves are suitable for pneumatic and hydraulic applications . A wide range of operating pressures and flow rates are available .
Space rated manual fill and drain valve
Spacecraft and satellite applications include the pressurisation of diaphragm-equipped propellant and oxidiser tanks for Reaction Control Systems ( RCS ) and Altitude Control Systems ( ACS ) with pressurant . These tanks are designed with a flexible diaphragm to separate the pressurant from the liquid propellants and oxidisers . Manual valves allow ground crews to pressurise the pressurant end of the tank with helium or nitrogen , typically at pressures as high as 8700 PSIG . The pressurant is then regulated and introduced into the pressurant end of the propellant and oxidiser tanks . Manual fill and drain valves control the pressurisation and venting of the pressurant , propellant and oxidiser tanks during pre-flight testing and final pressurisation for flight . These valves are capable of multiple operations and require extremely low internal and external leak rates of 1 × 10 -6 sccs GHe at 4000 PSIG . This is particularly critical as the valves , once closed for flight , must maintain this leak integrity as the time duration between pre-flight filling and actual flight can be lengthy . In the past , endurance was not a significant issue . Most valves would not see more than 10-20 in-service cycles , as the craft were essentially single use devices . With today ’ s push for reusable spacecraft , life cycle becomes more important . Life expectancy of more than 50 cycles is not uncommon .
About the company Valcor Engineering creates custom manual valve designs for aircraft , spacecraft and ground support equipment . Valve actuators include handles , levers , and push buttons . Valve designs include two-way , three-way and four-way porting . Valcor offers a total system integration capability , including the manifolding of valves and other pressure , flow control and measurement components into fully tested turnkey systems . www . valve-world . net