For emergency assistance, please call +44 (0)1494 429800

On-Site Crankshaft Annealing

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.

Benefits of Crankshaft Annealing

  • An otherwise scrap crankshaft can be saved
  • Service is provided on-site within the engine
  • Less diameter reduction on the journal
  • Extended shaft / crankshaft life
  • Avoidance of special undersize con rod

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).

We Are The Original On-Site Repair Company

Originally founded in 1952, Nicol & Andrew was the first company of its kind in the world to carry out in-situ machining and repairs on marine propulsion units.

We invented the tools to do the job on-site. Our orbital tooling system revolutionised the repair of crankshafts whilst still fitted in the engine. The system rotates around the damaged crankpin, so there is no need to remove or rotate the crankshaft.

A huge benefit is the reduction of downtime suffered by clients with crankshaft (crankpin and main journal) failures. A repair can be completed in just two or three days in many cases.

Why Clients Use Nicol & Andrew


We Cut Your Downtime

Our orbital repair process means we bring the repair workshop to you. For some repairs, we can get you back running in as little as 12 hours.


We Save You Money

Your equipment does not have to be stripped down and transported or re-assembled. The savings on this alone are very significant.


All Major Industries Served

We are a world leader in in-situ repair technology and on-site repair services. Our worldwide customer base includes companies in the manufacturing, marine power, petrochemical, paper, process, oil and gas industries.

What Our Clients Say

Very pleased with the speed and standard of repair to our diesel engine. Please thank your technicians for going the extra mile to ensure it was finished on time.


Another first class repair from your technicians. Please thank them for a timely repair and for working so hard under difficult conditions. Our engine is back up and running with no problems.


A Bad In-Situ Repair Could Scrap a £500,000 Crankshaft

If you need a fast response, worldwide, from an expert team with over 65 years’ of in-situ crankpin machining experience, call us now on +44 1494 429800.