Vacuum valves: Edwards (formely known as BOC Edwards) vacuum valves

Edwards BRV Backing/Roughing valves

Edwards BRV Backing/Roughing valves

• Easy to operate – both ports closed position

• Long life – 100000 operations or more

• Choice of manual of pneumatic actuation

• Position indicator on pneumatic valve

• NW10 and NW25 sizes available

• Leak tight to better than 10^-9 mbar | s^-1 / 8 x 10 ^-10 Torr | s^-1

• Two new versions of the BRV25PK are available, C32304900 has the pumping and bakcing ports in-line, which C32303500 has NW25 flanges on all three ports.

Edwards (Formerly BOC Edwards) 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, and are available in nominal sizes of 10 and 25 mm diameter. The valves have been designed particularly for the Diffstak® pumping systems, but have applications where a compact change-over valvse is required in he pressure range 10^-7 – 2000mbar / 8 x 10 ^-8 – 1500 Torr.

The BRVP models are actuated by an intregral pneumatic cylinder, complete with two microswitches for indicating port position. The BRV is manually operated by a lever and cam through 180 degree movement.

An important feature of the both models is the mid-position, where both ports are isolated from each other, and from the common (or rotary pump) port. Additionally, isolation between the backing and roughing ports is positively maintained during actuation. Both ports are closed under spring pressure and sealed by fluoroelastomer 'O' rings. Each port is leak tight to better than 10-9 mbar / 8 x 10 -10 Torr | s-1 against 1 bar differential.

A flexible neoprene connector is supplied for the backing connection. The roughing and forepump ports terminate in the appropriate NW termination.

Technical data - Edwards BRV Backing/Roughing valves

Construction materials:

Body and pneumatic cylinder: HE 30 TF aluminium

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 | s^-1

<8 x 10^-10 Torr | s^-1

Across ports <10^-9 mbar | s^-1

<8 x 10^-10 Torr | s^-1

NW Coupling <10^-9 mbar | s^-1

<8 x 10^-10 Torr | s^-1

Operating pressure range: 10^-7 – 2000 mbar / 8 x 10 ^-8 – 1500 Torr

Maximum baking temperature

BRV10P, BRV25P: 70°C

BRV10M, BRV25M; 90°C

Reliablity (MTTF): 100000 cycles

Recommended air pressure: 2.3 – 4.2 bar / 40.6 – 61 PSI

Max air pressure: 7 bar/102 PSI

Min air pressure: 2.4 bar / 35 PSI

Air connectionsL 1/8 in BSP, for 6mm Ø plastic or copper tube

Microswitching rating: 24V 1.5 A a.c. or d.c.

Weight

BRV10K 350g / 12 oz

BRV10PK 380g / 13 oz

BRV25K 860g / 30 oz

BRV25PK 900g / 31.7 oz

Ordering information -  Edwards BRV Backing/Roughing valves