Watson-Marlow 620RA - Manual (Page 8)

ATEX: Watson-Marlow 620RA, 620REA and 620RE4A pumpheads User Manual 8
9 Servicing and cleaning requirements
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 mechanisms
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. The same cleaning procedure should be
used to limit the build up of dust (which can become electrostatically charged and/
or heated by friction).
Because of the importance of dissipating any electrostatic charge the earthing lead
should be regularly checked for signs of corrosion.
Rotor removal and re location
Remove the rotor cover and central locating bolt using a 5mm Allen key. Pull the
rotor off the keyed shaft, remove the key and clean thoroughly. Do not use tools to
lever the rear face of the rotor away from the inner face of the track; it should come
off by hand.
To replace the rotor, locate the key into the keyway and apply a thin layer of grease
over the shaft and key. Align the keyway of the rotor to the shaft key and slide
the rotor into position, ensuring that a positive “stop” is achieved and ensure that
the full length of the drive shaft is fitted into the rotor. Do not force the rotor into
position. The rotor will slide into place easily if correctly aligned.
Tighten the hexagonal locating bolt to a nominal torque of 10Nm using a 5mm Allen
key.
The rotor bolt, which is impregnated with “Loctite 218” thread lock, should be
subjected to a maximum of three removals/relocations before renewal. To avoid
rotor bolt renewal after three removals, apply “Loctite 222” thread lock to the rotor
thread before relocation. This is critical to ensure prolonged, secure location of the
rotor hub to the drive shaft. Failure to complete this action will invalidate the terms
and conditions of the pumphead warranty.
Replace the rotor cover.