Siemens SIMOTICS M-1PH8 - Page 110

• First screw the 󹪞exible hoses onto the rotor-supported rotating union. Then screw the
rotating union onto the shaft with the speci󹪝ed torque.
• Avoid stressing due to incorrect hose lengths and unsuitable mounting material.
• The rotating union must be easy to turn when mounted.
• Keep rotating unions free of chips and burrs.
• Position the rotating union horizontally in such a way that the leakage connection is at the
lowest point.
• Always route the leakage hose downward at at least 15° with a large cross-section.
• If the leakage hose is higher than the leakage connection and the mechanical seal is open,
the rotating union and possibly also the motor will be 󹪞ooded. The motor can fail.
• Also route the inlet hose downward. This causes the coolant to 󹪞ow back in the supply line
when the mechanical seal is open (e.g. tool change or standstill) and not through the motor
shaft and the leakage connection.
• Filter the coolant so that no particles or chips can reach the mechanical seal and damage it.
Note
Mounting the rotating union
• During assembly, screw the thread absolutely tightly into the NDE shaft extension. Ensure
that no coolant can leak.
• Check the rotating union and hoses regularly for tightness.
Mechanical properties
4.6Mounting of rotating unions on 1PH8 hollow-shaft motors
1PH8 SIMOTICS M main motors
108 Con󹪝guration Manual, 12/2022, A5E51895839A