Sperre HV2/210, Instruction Manual

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Instruction manual for Water-cooled Air Compressor HV2/210 - 9 -
5.5. Piston and piston rings
Dismantle the piston as follows:
LP piston
A. Remove the cylinder head without dismantling the valves.
B. Remove the big-end bearing bolts and bearings.
C. Withdraw the piston and connecting rod from above.
Assembly sequence is the opposite of the above.
HP piston
AA. Remove the big-end bearing bolts and lower bearing shell. Turn over the crankshaft to top dead centre and
then back. The upper bearing shell can now be removed.
BB. Turn over the crankshaft to bottom dead centre, then withdraw the piston and connecting rod through the
crankcase door.
Assembly sequence is the opposite of the above.
5.6. Flexible coupling
The compressor flywheel serves as one coupling half.
Dismantle the coupling
A. Loosen the nuts on each coupling half and give each one a sharp tap with a hammer before removing them
completely. This will cause the bolts to loosen from their conical holes in the coupling halves.
B. Remove the bolts and take out the flexible coupling. Avoid spilling oil on the flexible coupling.
The coupling half on the motor is keyed and shrunk on to the axle.
Alignment
The prinsiple and values for checking alignment are shown in Fig. 4.
A. Micrometer/dial indicator
B. Magnetic base
C. Flywheel
D. Coupling half, motor
E. Flexible coupling
Check the angle (W) by means of inside micrometer callipers or vernier callipers. The distance (W) in mm should
be the same around the whole circumference of the coupling halves.
Check parallel misalignment (A) between coupling halves as shown, around the circumference of the coupling
halves (C). Values in mm for maximum parallel misalignment are given in Fig.4.