Description - Edwards Diffstak 63/150 Instruction Manual

Mk2 diffusion pumps

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B344-21-880 Issue N

1.2

Description

The Mk2 series of Diffstaks are compact high-performance diffusion pumps which provide exceptionally clean

pumping without the use of extra traps or baffles or the need for liquid nitrogen cooling.

The basic Diffstak consists of a diffusion pump, a water-cooled baffle, a high-vacuum isolation-valve and a roughing

connection all integrated into a water-cooled stainless steel casing. The high-vacuum isolation-valve is part of the

inlet-flange and is configured for either manual or pneumatic operation.

Pneumatic high-vacuum isolation-valves have position indicators which indicate whether the valve is open or closed.

You can connect the position indicators to your control or indicator equipment.

Four sizes of pumps are available with either a 63 mm, 100 mm, 160 mm or 250 mm diameter inlet-flange. The

largest pump has a pumping speed of up to 2000 l s

without the backing/roughing connection, for use in applications where high ultimate vacuum is of prime importance,

or for pumping systems where a high-vacuum isolation-valve is not required.

Two unvalved versions are also available, for use in applications where the highest ultimate vacuum is required.

These unvalved versions have 6 or 8 inch diameter flanges for use with copper compression gaskets. This provides

simple, reliable, metal-to-metal sealing and is ideally suited to ultra-clean applications. An ultimate vacuum of less

-10

than 2 x 10

mbar (2 x 10

The basic models are as follows:

M-model pumps have a manually-operated high-vacuum isolation-valve.

P-model pumps have a pneumatically-actuated high-vacuum isolation-valve.

C-model pumps have an unvalved collar suitable for use with a bolted rotatable flange.

F-model pumps are unvalved and have a copper compression gasket (ConFlat) flange.

Note:

Cryo-cooled Diffstak pumps are also available in the same four sizes as the valved and unvalved pumps.

These cryo-cooled pumps have a high conductance, liquid nitrogen cooled disc located above the

water-cooled baffle. The pumps are designed for use in applications which require minimum pump down

times when heavy vapour loads are pumped.

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Pa) can be achieved with a low temperature trap.

Edwards and the Edwards logo are trademarks of Edwards Limited.

. All four sizes of pump are available with unvalved collars and

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