WIKA CPB3800 - Handbuch (Seite 40)

40 WIKA operating instructions model CPB3800
14062232.03 12/2013 GB/D
GB
7. Maintenance, cleaning and recalibration
7.4.4 Overhaul and re-certification
To provide the best possible service, the pressure balance should be returned as
complete units comprising the base, the piston and cylinder unit, and all the weights.
The base can also be serviced itself. The piston-cylinder unit with weights has to be sent
back for overhaul. In such instances, certification issued after overhaul can only refer to
the piston and cylinder and weight set numbers and not to the base to which they were
originally fitted.
Pressure balance bases will be stripped, all pipework cleaned, all seals replaced, worn
components replaced where desirable, and all reassembled and tested.
The weights will all be checked and brought to within original limits if possible. If one or
two weights are missing or beyond economical repair they will be replaced. If more are
missing/ beyond economical repair customer instructions will be sought.
The piston unit will be checked for accuracy and sensitivity. If it is not satisfactory for any
reason a quotation will be submitted for a replacement unit.
A new certificate of accuracy will be issued for each overhauled pressure balance.
Unless otherwise instructed on order when there has been a slight change in area of
the piston unit the certificate will reflect this; the accuracy will not be affected by more
than 0.03 %. For example the certificate of accuracy of an overhauled pressure balance
might show that the error does not exceed 0.05 % when the original certificate shows
that the error did not exceed 0.02 %.
We can issue an UKAS or DKD/DAkkS certificate of calibration for an overhauled
system. Details will be supplied on request.