Best Practices for Flushing Gearboxes and Bearing Housings

worm speed reducers

Planetary speed reducer (gearboxes)

CycloIdal gear reducers

HELICAL GEAR REDUCERs

Gearbox for Agricultural

variators

Spiral Bevel Gear reducers

gear motors

electric motors

screw drive

Worm&Bevel Gear Operators

Transmission System for solar Generator

Hydraulics Drive

shaft mounting gearbox

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Best Practices for Flushing Gearboxes and Bearing Housings

　　Gearboxes and bearing housings periodically need a thorough flushing rather than a simple drain and fill. There are several tell-tale signs thatwould point to the requirement, such as overheating of the sump, gross liquid or solid contamination, development of a severe wear pattern, etc.
　　Material evidence in the form of sludge, rust, moisture, wear metals, gel or other viscous residue noted at the initial moment that the drain beginsshould confirm to the technician that a flush is in order. A thorough flush is also useful to remove construction and assembly contaminants fromequipment sumps prior to commissioning.
　　With these factors in mind, what constitutes a thorough sump flush? Are there any particular problems that the operator should be careful toavoid? What equipment can or should be used for this purpose? Finally, what items should be included in a detailed flushing procedure?
　　What is Flushing?
　　Flushing is a clean fluid circulation process designed to removewater, chemical contaminants, air and particulate matter (notfixed to surface) resulting from construction, normal ingression,internal generation or component wear.
　　Flushing process can be useful in many differentcircumstances, such as:
　　1.For new or rebuilt machines to remove contamination resultingfrom manufacture, service or overhaul. The fluid system can beseriously contaminated from dirty assembling elements,corroded surfaces, water, oxidation products and incompatibleelastomers such as seals, sealants, coatings, etc. Also, duringthe assembly process, dirt is ingested and debris is generateddue to threading, joining, welding, etc.
　　2.For in-service machinery after an oil change due to heavy fluidcontamination, component failure, extremely degradedlubricant (oxidation), or if a system flushing has not beenperformed in the past three years.
　　3.For gearboxes and bearing housings that are not fitted withfiltration, flushing is required to remove contamination andsediment. Water, rust, excessive wear debris, sludge, varnish orlacquer, hard to open drain port, etc., all suggest systemcontamination problems and should trigger a hard look at athorough flush, because 10 percent of the old contaminated ordepleted lubricant may be enough to use up most of theadditives of the new oil gear reducer.