BRV25K Backing/Roughing Valve, Manual Operation

Backing/roughing valves with ISO NW roughing and forepump terminations feature manual or pneumatic actuation. They combine the function of separate backing/roughing valves in one integral 3 port unit.
 
A flexible neoprene connector is supplied for the backing connection. The roughing and forepump ports terminate in the appropriate NW termination.

Features and Benefits

  • Easy to operate - both ports closed position
  • Long life - 100000 operations or more  
  • Leak tight to better than 10-9 mbar l s-1 / 8 x 10-10 Torr l s-1

Applications

  • The valves have been designed particularly for the Diffstak® pumping systems, but have applications where a compact change-over valve is required in the pressure range 10-7 - 2000 mbar / 8 x 10-8 - 1500 Torr.
Technical data  
Construction materials  
Body and pneumatic cylinder HE 30TF aluminum
Lever and bonnet (manual) Glass reinforced plastic
Operating shaft/valve seat Stainless steel
Body seals, port seals, shaft seal ‘O’ ring Fluoroelastomer
Leak rate  
Overall < 10-9 mbar ls-1/ < 8 x 10-10 Torr ls-1
Across ports < 10-9 mbar ls-1 / < 8 x 10-10 Torr ls-1
NW coupling < 10-9 mbar ls-1 / < 8 x 10-10 Torr ls-1
Operating pressure range 10-7 - 2100 mbar / 8 x 10-8 - 1575 Torr
Max baking temperature  
Pneumatic 70°C
Manual 90°C
Reliability (MTTF) 100000 cycles
Recommended air pressure 2.8 - 4.2 bar / 40.6 - 61 psi
Maximum air pressure 7.0 bar / 102 psi
Minimum air pressure 2.4 bar / 35 psi
Air connections 1/8 in BSP, for 6 mm Ø plastic or copper tube
Microswitch rating 24 V 1.5 A a.c. or d.c.
Weight  
BRV25K 860g / 30oz