WIKA CPB3800 Betriebsanleitung Seite 37

7. Maintenance, cleaning and recalibration
7.2.6 Hub assembly
1. Unscrew the ram from the spindle. NOTE: left hand thread.
2. Unscrew the spokes from the hub.
3. Knock out the spring pin (1), found at the bottom of one of the tapped spoke holes in
the hub, using a punch 6 mm dia. Pull off hub.
4. The hub locating plate and thrust bearing can now be removed from the spindle.
5. If the flanged bush (2) is to be renewed, it should be pressed out of the locating
plate and a new one pressed in squarely.
6. The thrust bearing (3) is renewed as a complete assembly.
7. The nut, pin and spindle sub-assembly (4) can only be replaced as a matched pair.
Unscrew the nut from the ram, gripping in a soft jaw vice and screw in the new nut.
8. Assemble the thrust bearing, locating plate and hub on to the spindle, lubricating
with molybdenum disulphide grease.
9. Clamp these items together to eliminate end play and re-assemble spring pin. If
using new spindle drill through 6.3 mm diameter to fit spring pin (1).
10. Lubricate the thread with molybdenum disulphide grease and screw into ram nut.
7.2.7 Piston-cylinder unit
As the piston-cylinder unit represents a high proportion of the total value of the pressure
balance, it should always be handled with care and every effort made to keep it clean.
The piston-cylinder unit is made to extremely fine limits of accuracy and it is not
advisable to dismantle it. If it is necessary to clean it, the piston and cylinder bore must
be oiled immediately, in order to protect the high grade finish.
Should the unit become damaged it should be returned complete for replacement or
repair. Parts from different units are not interchangeable as they have to be weighed and
evaluated as a whole.
The serial number of the piston-cylinder unit appears in the certificate of accuracy and
is marked on the body of the unit. This number, as well as the pressure balance serial
number should always be quoted in correspondence concerning the piston/cylinder unit.
The piston-cylinder connections should be blanked if it is removed from the pressure
balance. If the unit is taken off for any reason it should be stored upside-down, resting
on its weight carrier.
WIKA operating instructions model CPB3800
GB
37