Repair of shafts, bearing journals, seal surfaces, housings and pump parts by undercutting the damaged area, spraying a buildup coating and finishing to print size. It saves long-lead parts at a fraction of replacement cost and avoids the heat and distortion of weld repair. Specs limit thickness and exclude some surfaces, such as heavily loaded press fits and areas under severe impact.
Bearing seat is 0.003 under, do a dimensional restoration with 420 stainless and grind back to print.
Spray restores size, not strength: a shaft worn from overload still carries the same load on the same reduced core.
Also heard as
- buildup
- salvage
- rebuild
- restoration
Related terms
Undercut
A recess deliberately machined below finished size so the coating can fill it to full thickness.
Grind stock
Extra coating thickness sprayed beyond the final size so it can be ground or machined to finish.
Nickel aluminum
Nickel-aluminum composite that reacts in the flame to give a strongly bonded first layer.
Cold spray
Process that fires solid metal powder at supersonic speed so it bonds by impact rather than melting.