On-Site & In-Situ Crankshaft Annealing

When your crankshaft fails it can often leave very high hardness levels in the crankpin (greater then 600Hb).

For an effective repair those hardness levels need to be reduced. Nicol & Andrew has now successfully salvaged many crankshafts throughout the world, saving the crankshaft and saving the cost of shaft replacement or major engine rebuilds.

In addition to our long established in-situ machining repair method where we remove excessive hardness from heat damaged journals with our orbital equipment, we also provide an in-situ annealing option when the hardness is too deep to be eliminated within the manufacturer’s limits.

This crankshaft annealing option only requires that the crankpin journal be free of any heat cracks, which the initial pre-machining will determine.

After annealing, a greatly reduced amount of re-machining and polishing is necessary to end up at a standard undersize. A much greater life expectancy of the shaft is normally realised.

Occasionally shafts that have overheated locally also end up bent. Experience has shown that our pre-machining and annealing process often reduces any bend present.

If a slight amount of bend still remains, this can often be straightened in the engine by a careful process of peening and machining (and where required additional heat treatments). This has been shown to be a highly successful process over many years (100% where excessive bend is not present).