Watson-Marlow 620U - Manual (Page 87)

Watson-Marlow 620UN, 620U, 620SN, 620S User Manual 87
26.8 620RE, 620RE4 and 620R
tube element or continuous tube removal
Always isolate the pump from the mains power
supply before opening the guard or performing
any positioning, removal or maintenance.
Unlock the guard and disengage the rollers.
Disconnect the tubing from the external pipeline.
Remove the tubing from the pumphead.
26.9 620RE, 620RE4 and 620R
maintenance
Scheduled maintenance
The stainless steel pumping rollers run on sealed bearings and do not require
lubrication.
Remove the rotor and lubricate the follower rollers and roller engaging mecha-
nisms with a lithium-based grease. This should be carried out every six months
for intermittent duties and every three months for 24 hour duties.
If fluid is spilled inside the pumphead, flush the pumphead out with water and
mild detergent as soon as possible. If specific cleaning agents are required to
clean the spillage, please consult Watson-Marlow Technical Support Office
before proceeding, in order to confirm chemical compatibility.
If the rotor needs to be removed, refer to the guidelines below.
Roller adjustment
620 pumpheads have provision for adjustment to reset the roller/track gap to com-
pensate for wear after extended service in arduous applications.
Roller/track gaps can only be accurately judged without tubing in the pumphead.
The gap should be 4.6mm for 3.2mm wall tubing and 5.5mm for LoadSure ele-
ments.
If the gap is more than 0.2mm greater than these dimensions, the following may be
carried out:
Note the number on the roller arm to which the engraved line on the hexagon-
headed main roller pin corresponds.
Remove the circlip (snap-ring) and roller pin.
Relocate the main roller pin, resetting the engraved line to one number lower.
For example, if the engraved line was at "-1", reset it to "-2" to reduce the
roller track gap.
Ensure the roller pin is correctly seated into the roller arm thrust washer.
Replace the circlip.