STP Series Turbomolecular Pump 
 
INSTALLATION OF THE STP PUMP
 
 
2.3.3  Secure the STP pump 
WARNING 
 
The STP pump is provided with a high-speed rotor. Any internal abnormality/error 
may result in a jump in rotational torque leading to personal injury or peripheral 
equipment damage. 
 
The STP pump is provided with a high-speed rotor. The worst-case failure may result in a jump in 
rotational torque leading to personal injury or peripheral equipment damage. 
The method of securing the STP pump will depend on the STP pump model and its installation 
requirements. Secure the STP pump to the vacuum equipment as "HOW TO SECURE THE STP 
PUMP" in the STP Pump Instruction Manual (B). 
The STP pump is a component system when installing to the semiconductor equipment. Consider 
the following when installing to the semiconductor equipment. 
• Confirm that electric resistance value between the STP pump and vacuum equipment is set to 
0.1 Ω or less after securing the STP pump to the vacuum equipment. 
 
2.3.4  Precautions of vacuum piping 
CAUTION 
 
DO NOT open the STP pump through the flange to atmospheric air while the STP pump is 
running. If atmospheric air flows into the STP pump, it may not function normally. 
 
Depending upon the type of the backing-pump used, atmospheric air may reverse flow into the STP 
pump when the backing-pump stops. 
Attach a vacuum valve to the middle of the piping between the STP pump outlet port flange and the 
backing-pump, and close the vacuum valve when the backing-pump stops. 
In order to let the STP pump bring its performance into full play, follow the precautions below: 
1.  Be careful not to scratch the flange of the STP pump and vacuum equipments. Before installing 
the STP pump, check whether or not there are scratches on the surface. 
2.  Use steel or aluminum tubes with a low gas loss to connect the vacuum equipment to the STP 
pump. 
3.  Take measures for minimizing leakage. It is also necessary to degrease the tubes as regularly as 
possible to keep the gas loss as low as possible. 
4.  There is a recommended backing-pump of pumping speed. (Refer to "TECHNICAL DATA" in the 
STP Pump Instruction Manual (B). However, the pressure at the inlet and outlet ports varies with 
the flow rate of gas, capacity of the vacuum equipment, length and material of the piping.