Slow Down Installation Speed
Because heat generated by friction is a contributing factor in galling,
slowing down the installation speed can prevent galling. It is recommended
that power tools not be used for the installation of stainless steel
or other fasteners prone to galling. This is especially important when
using nylon insert lock nuts as these nuts significantly increase the
chance of galling.
Don't Use Bolts to Pull Joints Together
Bolts are not designed to pull together a joint or force materials into
position. Doing so drastically increases the chance of galling. The materials
being bolted should already be in place so the nut can be spun down by
hand until the final tightening. If necessary, use clamps to hold the
joint together during bolting.
Use a Lubricant
Special anti-seizing or anti-galling lubricants can be used to dramatically
reduce the chance of galling. Examples include
MRO Solutions 1000 Antiseize,
Permatex® Anti-Seize Lubricant,
Finish Line™ Anti-Seize Assembly Lube and USS Ultra Tef-Gel®.
Even a standard lubricant, such as WD-40®, can help reduce friction and
prevent galling. Some nuts are
available with a waxed finish
to reduce the risk of galling.
Avoid Damaged or Dirty Threads
Check for damage to the threads of each bolt, especially bolts with fine thread.
You should be able to put a standard nut on a bolt by hand. If not, it may
indicate dented or damaged threads.
Also note that debris in the threads of a fastener can greatly increase the chances
of galling. Always use clean parts.
Use Extra Care With Lock Nuts
Nylon insert lock nuts and, especially, prevailing torque nuts generate a large
amount of friction and heat during installation. If you are experiencing
galling problems, slow down installation speed or consider a different locking
If a Fastener Begins to Bind: STOP
If a fastener begins to bind before you are actually tightening it down,
stop immediately. Wait a minute or two to allow any heat to dissipate and
then back the fastener off. Inspect the threads for damage and
try again with a new nut.