Edwards Diffusion Pumps: Diffstak Model 63/150 (Unvalved)

If you are replacing a diffusion pump on your mass spectrometer and have the model number or pump specifications, give us a call and we can supply a replacement.

The cryo-cooled Diffstak has a liquid nitrogen cooled inlet baffle with an integrated liquid nitrogen reservoir. The cryo-cooled Diffstak is ideal for applications where very high vapour loads are pumped. Like standard Diffstak, the cryo-cooled Diffstak is available in four sizes with either manually or pneumatically operated high vacuum valve.

The standard Diffstak is the basic model, available in four sizes, with a water-cooled inlet baffle. The high vacuum valve is part of the inlet flange and can be either manually or pneumatically operated. The standard pump offers clean and fast pumping without the need for liquid nitrogen.

There are three types of Diffstak available: the standard Diffstak, the cryo-cooled Diffstak and the unvalved Diffstak.

Scientific Instrument Services can supply the full range of Edwards Diffusion Pumps. This includes the Diffstak series including the models 63/150, 100/300, 160/760 and 250/2000 as well as the many other models available.

The conveniently located dipstick and drain assembly allows you to check the fluid level, to drain the fluid and to pour more fluid into the pump while the pumps remain connected to your vacuum system.

The heater in the Diffstak is a flat plate which is easy to replace and which means that the electrical terminal box on the base of the pump can be rotated to suit your application.

A mounting plate is fitted to the ejector stage to accommodate an optional thermal snap-switch.

The Diffstak pump has a gauging port in the integral roughing line to allow you to fit a Pirani gauge head to monitor the system pressure.

Diffstak features

The standard Diffstak contains no high vacuum valve. The unvalved Diffstak is best for applications where the highest ultimate vacuum is required, or where a high vacuum valve is not needed. Other models available on special request.

The Diffstak pump has a one-piece jet assembly which is easy to remove, clean and replace. The Diffstak is a fully fractionating pump. The ejector stage ensures high backing pressure performance and continuous fluid purification.

The integrated design of the Diffstak results (when compared with conventional diffusion pumps) in a reduction in the number of elastomer seals required to complete the installation. The neat and compact Diffstak therefore offers exceptionally clean pumping with virtually no outgassing.

The standard Diffstak consists of a water-cooled diffusion pump, an inlet baffle, a high vacuum valve and roughing line connections all integrated in a single, vacuum brazed, stainless steel casing.