Inspection and repair on ZF ZFW43100 NR gearbox

This client from Turkey came to us with this ZF ZFW43100 NR. We inspected the gearbox and performed a repair. After a succesful testrun we shipped the gearbox back to the client.

This report presents the inspection of the propulsion gearbox of a vessel. GBS was invited to perform a preventive inspection in order to determine the conditon of the gearbox.

The state of the gearbox can be considered as good, only minor running marks were observed on gears and bearings. Furthermore, the gearbox externals and engine room were very clean at the time of the inspection.

Since no drawings of the gearbox were available it was not possible to determine all bearing positions. It can be expected that a combination of radial and axial bearings is present on some shafts, however these where not accessible through the bearing in front. If the thrust bearing is severely damaged it could transfer damage to the next bearing on the shaft by means of indentation of debris, no such damage has been observed.

Another way to detect bearing damage when the bearing is not accessible is by means of oil analysis, a service which we provide.

For future inspections it is advised to provide more information about the gearbox in the form of drawings or a parts list.

Recommendations are:

- To continue annual visual inspections
- To perform oil analyses on regular intervals.