Edwards EXT 70 turbo pump, EXC100E controller, Pfeiffer PKR251

High Vacuum system components:
Edwards EXT 70 turbo molecular high vacuum pump
Edwards EXC100E Controller
Pfeiffer PKR251 Full range Vacuum Gauge

With user Manuals for both instruments

Edwards E2M1.5 Support pump also available: Stock Reference H091


Turbo Pump:
Edwards EXT 70 turbo molecular high vacuum pumps have a pumping speed of 70 liters per second (l/s). The

Edwards EXT 70 turbo molecular pump inlet is ISO63 with a KF-16 exhaust foreline flange.

The Edwards EXT 70 turbomolecular pump can be used for all general-purpose high vacuum applications.
Flow rate; 70I/s
Final Ultimate Pressure 1 x 10 -9 Torr
Inlet ISO63
Outlet KF16

Compatible Controllers: EXC 100E, EXC 120, TIC Series
Recommended Backing Pump E2M0.7 or E2M1.5



General Overview:

The EXT70H, EXT70Hi, EXT250H and EXT250Hi pumps are compound vacuum pumps that combine a turbomolecular pump and a drag pump on a single shaft.

The turbomolecular pump is made from a multi-stage axial-flow turbine which is optimised for operation in molecular flow conditions. The drag pump is made from pumping channels formed by plane rotating disks. The drag pump is designed for operation at higher pressures than conventional turbomolecular pumps.

The light alloy rotor is machined from one piece to form the angled blades of the turbomolecular pump and the disks of the drag pump. The rotor blades rotate between angled stator blades which are supported by spacer rings. The rotor and stator blades have an open structure at the pump inlet, and a more closed structure at the outlet. This configuration gives an optimum combination of pumping speed and compression when pumping gases of both high and low molecular weight. For the blades to be effective, their speed must be close to the thermal velocity of the gas. The rotor of the EXT70H/Hi therefore rotates at up to 90000 r min-1, and the rotor of the EXT250H/Hi therefore rotates at up to 60000 r min-1.

Gas from the inlet is compressed through each of the bladed stages of the turbomolecular pump and transferred to the drag pump. In the drag pump stages, the gas is further compressed as it is pumped around the channels formed by the separation of the disks. The inlet and outlet of each channel is separated by a close-running seal which diverts the gas through a port to the next channel, or to the pump outlet.

The rotating assembly is supported at the inlet end by a frictionless magnetic bearing and by a precision ceramic ball bearing at the outlet end. The ball bearing is lubricated from an oil reservoir and wick mechanism.