WIKA CPB3800 - Handbuch (Seite 29)

29 WIKA operating instructions model CPB3800
14062232.03 12/2013 GB/D
GB
6. Commissioning, operation
2. Load the weights equivalent to the desired pressure. Each weight is marked with its
pressure value. The piston-cylinder unit has a basic lb/in² start, for other pressure
units a make-up weight is added to the piston head for conversion to bar.
For calibrating pressures less than the pressure value of the overhang
make-up weight value, it is recommended that the top loading weights
are used for calibration. When the required pressure calibration unit is
bar, it is essential that the small make-up weight is fitted first before any
other top loading weights.
For calibrating pressures greater than the pressure value overhang
make-up weight value, the overhang should be fitted. All top loading
weights must be removed before fitting the overhang.
When the overhang is fitted, the initial weight that goes onto it is a large
annular make-up weight. The small type make-up weight should not be
used when the overhang is fitted.
6.6.1 To apply pressure
For pressures up to 140 bar (2,000lb/in²)
1. Close valve B (valve A remaining open).
2. Wind spindle pump handle clockwise. This will generate pressure up to approxi-
mately 140 bar or 2,000 lb/in², as handle is wound in. When handle becomes stiff to
rotate this will indicate that the pressure limit for this range has been reached.
For pressures above 140 bar (2,000lb/in²)
1. Ensure valve B closed and valve A open.
2. Wind spindle pump handle clockwise until the handle becomes stiff to operate.
3. Close Valve A and open valve B.
4. Continue to wind spindle pump handle clockwise. This will generate pressure up to
approximately 1,200 bar or 16,000 lb/in².
5. When the piston rises and appears to floats, this indicates it is at its nominal desired
pressure. When only top loading weights are being utilised, a blue and yellow band
indicates the float position. When the overhang is being employed, the bottom of
the overhang will line up with a machined groove in the piston holders main body, to
indicate its nominal desired pressure.