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Million Cycle Circular Gate Valves


Circular Gate Valves

In the simplest of terms, vacuum gate valves are devices that regulate the flow of gases, fluids or materials through a structure or aperture by opening, closing or obstructing a port or passageway. Gate valve assemblies consist of three key components: an actuator, a carriage/gate and a valve body. The actuator provides the power to position or transport the valves carriage/gate. The actuator is attached to the valves body via a rectangular bonnet flange. The gate closes or opens one of the valves body ports. The valve body is a vacuum tight chamber that is screwed, flanged or welded into a larger vacuum vessel or system.

lt is worth noting that reliable vacuum valves were not commercially available until the late 1940s with the advent of 0-ring elastomer seals. The elastomer 0-ring was developed for use in aircraft hydraulic systems, and was soon thereafter adopted by the vacuum community as the standard means of making vacuum seals. Prior to this it was common practice, even in large research establishments, to upgrade general service valves for vacuum use by winding actuator shaft gaskets from string soaked in an Apiezon grease. MDC Europe stainless steel vacuum gate valves incorporate patented C-Locm and Uni-LocN gate valve locking mechanisms. No contact is made between a valves body and the locking mechanism, a feature which markedly decreases vibration and insures smooth valve operation. MDC Europe gate valves require about half the number of moving parts found in comparable competitor valves. This reduction in moving components minimises wear and particulate generation which in turn provides valves of superior performance and reliability. The valves' low outgassing characteristics can be attributed to a fusion welded 300 series stainless steel body, welded AM-350 stainless steel nesting bellows as well as small cross-section 0-rings and the elimination of blind internal cavities. MDC Europe circular gate valves are offered in various sizes ranging from 16mm to 305mm port diameters. Standard port mounts include: CF metal seal flanges, which are recommended for ultrahigh vacuum service; ISO KF and ISO LF fast make and break elastomer sealed flanges, ideal for high vacuum applications requiring frequent assembly and disassembly. Gate valve actuation is available in both manual and electropneumatic configurations. Custom designed valves are available on request.

Circular C-Locm™ gate valves

Circular C-Locm™ gate valves can be fitted with optional high precision, modular mechanical position indicators (MPI). This new MPI system consists of two single pole double throw micro switches fitted with integral hinged lever and roller actuators. Each micro switch is wired in a normally open position. Normally closed switches are available on request, and easily modified by reversing standard factory wiring. Precise positioning of each micro switch is possible by a patented vernier mechanism found only on MDC Europe gate valves. MPI connections are made via industry standard seven pin circular threaded connectors supplied with mating female cable connectors. All pneumatic valves include solenoids prewired through MPI connector box.

 Standard gate valve features :
  • UHV and HV series
  • Ports with circular or rectangular apertures
  • CF, ISO KF or ISO LF port flanges
  • Manual and electropneumatic actuators
  • Patented C-LocN and Uni-Loc'" locking mechanism
  • 24V DC air control solenoid valve (Circular and rectangular gate valves)
  • OFE copper metal and Viton® elastomer bonnet seals
  • Welded bellows actuator seal
  • TIG welded internal body joints
  • Electropolished interior and exterior surfaces
  • Dry film lubricated bearings
 Optional Features:
  • Modular electromechanical position indicators
  • Valve body roughing ports
  • High temperature 250°C Kalrez® elastomer gate seal
Million cycle valves MC+ Features:
  • Enhanced to withstand I million cycles before requiring service.
  • Low vibration, quiet operation
  • Pneumatically locked in the closed position
  • Remains closed in the event of power loss
  • Fewer internal parts produce low particle generation


Mechanical position indicator Option -0 I

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Circular Gate Valves
For product listing, features and specifications click on links below
 DN16 16mm ports
 DN40 38mm ports
 Del-Seal® 3%" 50mm ports
 DN63 63.5mm ports
 DN100 102mm ports
 DN160 152mm ports
 DN200 203mm ports
 DN250 254mm ports
 CF355-304 I DN320LF 305mm ports