Stainless Steel Thread Galling & Prevention

Thread galling is a form of adhesive wear that occurs when metal surfaces rub together under pressure, causing material to transfer between mating threads.

In stainless steel fittings, this can cause thread damage, increased tightening resistance, or complete seizure of the connection.

Titan Fittings recommends proper installation procedures, compatible lubrication where permitted, and careful material selection to minimize galling risk.

Austenitic stainless steels such as 304 and 316 are susceptible to galling because of their ductility, work-hardening behavior, and tendency toward adhesive wear during sliding contact.

When similar stainless steel surfaces are tightened under high contact pressure, microscopic metal junctions can form and tear apart, damaging the threads.

Titan Fittings recommends considering thread design, material combinations, lubrication, and tightening practices when installing stainless steel threaded components.

Thread galling can be reduced by using compatible lubricants or anti-seize compounds where appropriate, keeping threads clean, avoiding cross-threading, and preventing excessive tightening speed or force.

Properly matching threads and following manufacturer installation instructions are also essential.

Titan Fittings recommends inspecting threaded components before assembly and replacing fittings with damaged threads.

Anti-seize lubricant can significantly reduce galling risk by lowering friction and limiting direct metal-to-metal contact during assembly.

However, it does not guarantee prevention under every condition, and its use must be compatible with the fluid, sealing method, and application.

Titan Fittings recommends choosing an approved lubricant and following manufacturer guidance, particularly for sensitive hydraulic, instrumentation, or oxygen-service systems.

Fittings with significant galling, torn threads, or seizure damage generally should not be reused.

Damaged threads can compromise engagement, sealing performance, and the connection's mechanical integrity.

Titan Fittings recommends replacing visibly damaged components rather than attempting to restore severely galled threads for pressure-containing service.

Thread galling is the surface damage caused by adhesive wear and material transfer between contacting threads.

Thread seizure occurs when the connection becomes difficult or impossible to turn or disassemble. Galling is one possible cause of seizure.

Titan Fittings recommends addressing the early signs of galling before extensive thread damage occurs.