Our Standard Overhaul and Repair Procedures and Practice

With our extensive repair experience of more than 100 gearboxes we have standardize the repair procedure of all types of gearboxes.

We are available 24 x 7 for any emergency breakdown in your plant.  


1) All speed reducers or assemblies will be:

  • Completely disassembled.
  • Hot Tank Stripped.
  • Cleaned, wire brushed of all rust and grease.
Inspected and/or tested as follows:
  • Measure all “fits” and compare with original drawing dimensions. Provide photographs and/or sketches for assembly.
  • Cases, housings, etc. – will be visually inspected for cracks and other signs of wear.
  • Shafts & Gearing – visual inspection and dimension checked, for possible reuse.

2) A detailed line by line quotation of all work required to recondition the assembly/speed reducer will be prepared and include:

  • Listing of any new parts required.
  • Summary of required procedures to return reusable parts to print specification.
  • Summary of price for labor and all materials to complete the job.






Repair Procedure: 


  • Checking fits and leakage from the fits if any. If leakage, need to repair with oil seals/sealant and required machining.


  • Repair may be made by plating and grinding, or machining and sleeving.
  • Will be straight and finished in accordance with tolerances and finish specifications as indicated on appropriate drawings.
  • New shafting provided will match the specifications and dimensions of the original part as per customer print.
  • Exposed threads, shaft ends and couplings will be protected with an anti-rust protection coating prior to shipping your Gear Box.


  • Will be dimensionally inspected to customer prints, manufacturers’ prints, or reverse engineered.
  • New gearing provided will meet or exceed the specifications and dimensions of the original parts as per customer print.

4.Gearbox Housing, Cases:

  • All bolts, studs, pipe plugs, and other fittings will be removed and the holes re-tapped as necessary.
  • Bolts, studs, and pipe fittings may be reused if in good condition.
  • Replacement bolts, studs, and pipe fittings will be of equivalent grade and material unless otherwise specified.
  • Split housing jointing surfaces will be machined / ground as necessary.
  • Bearing cases will be checked and machined as necessary

5.Assembly and Test Procedures:

  • All seals, shims, and gaskets will be replaced
  • All bearings will be replaced
  • All hardware will be reused or replaced depending upon condition.
  • All repaired and overhauled units will be run tested to check contact patterns, clearances, backlash, and freedom of movement.
  • When pressure lubricated units are involved, we will pressure test the unit when applicable.

6.Painting and Identification:

All speed reducers will have:

  • Exterior surfaces cleaned of all loose scale and rust.
  • Entire Housing surfaces cleaned of all dirt and oil.
  • One coat of light blue enamel applied on the exterior, unless otherwise specified by the customer.

7.A new identification tag will be installed to each overhauled speed reducer with the following information:

  • Date of rebuilt, Our serial number (to claim repair warranty)

8.Test Run Procedure:

  • Firmly mount gearbox to be tested to run test stand.
  • Fill the unit with lubrication
  • Attach the oil pumping station to the unit if required.
  • Hook up all run test equipment.
  • Check and note temperature.
  • Start test motor and set rpm to the gearbox requirements.
  • Check all sealed areas for any oil leakage.
  • Gearbox bearing temperature will be checked and noted at several intervals during testing.
  • Vibration and other nondestructive testing per customer requirements are available


  • All openings are properly protected with plugs or cover.
  • All units are shipped dry from our factory. The unit shall be marked to indicate that lubricant must be added prior to start of operation
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