IHI NIIGATA MG(L)26HLX, Инструкция по эксплуатации

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SECTION
４
- DISASSEMBLY AND REASSEMBLY
4.7 CRANKSHAFT
４－７－０１
4.7 CRANKSHAFT
The crankshaft is a one-piece, continuous grain flow forged steel crank with
induction hardened journals. Balance weights are located and secured by bolts
and dowels.
Crankshaft removal is required only if remachining of the main or rod bearing
journals is indicated by clearance or wear measurements, as outlined in Section 3.2.
If remachining is required, it should only be done in an approved service shop.
Periodic inspection of the rod bearings is recommended at settled intervals, and
inspection of the main bearings is recommended at other settled intervals
(Section 3.2). During these inspections, the condition of the crankshaft
journals should also be noted - if serious wear or
scuffing is apparent,
complete measurements should be obtained to determine if remachining is
required. Crankshaft deflections should be measured after the initial 100 hours
of operation and afterwards at 3000 hour intervals (Section 3.2).
Procedure for measuring crankshaft deflections
- Deflection is measured in both vertical and lateral directions. As
indicated in Section 3.2, slightly higher deflections are normal at the rear
main bearing because of the cantilever affect of the flywheel and/or
coupling.
CAUTION
Deflection measurements should be made when the engine is cold and with the
indicator cocks open at each cylinder.
- Install the dial indicator (supplied with special tool group) on the
crankshaft journal that is being measured in the position shown by 'A' in
Figure.