I'm looking for assistance in identifying the calculation,
or more specifically - the coefficient of friction, for determining the torque
required to move a mass along a horizontal rail track.
Basic design:
Base is a machined weldment weighing no more than 1,000 lbs,
includes a 200-pound allocation for the drive (gearbox/reducer) that I am
trying to size. The base will be holding
no more than 3,000 lbs of equipment. So,
total weight of moving base, not to exceed 4,000 lbs.
Current design has the 4 base casters as a combination of Flat
and V-Groove. Each caster is rated for
2,500 lbs with tapered roller bearings in the V-Groove and Roller Bearings in
the Flat roll.
Related to the drive mechanicals, looking at a AC VFD that
is C-Faced into either a Worm or RHB reducer (probably RHB - more efficient) that
drives a pinion gear. The motor,
reducer, and pinion gear will be mounted to the underside of the base with the
rack gear mount to the rail track. Rails
will be an inverted Structural Angle de-scaled and oiled for the V-Groove
Casters and a HRS de-scaled, or CRS, flat bar for the other.
Related to velocity, I'm looking at about 10 to 15 feet per
minute. So, assume a 1750 max RPM motor,
a 60:1 reduction, and a 16-tooth 8 DP Pinion.
Obviously, the reduction ratio, and the rack and pinion will be resized
once I get the output torque requirement of the gearbox.
But getting to actually sizing the output torque, sure the base
travel is a scalar application of Newton's 2nd Law plus a coefficient
of friction, but that's where my issue is.
Finding a coefficient of friction for two 6" diameter V-Grooved Steel
Casters, under load, traveling along an inverted de-scaled hot-rolled
structural angle that will eventually have particulate matter, either from
gradual oxidation and/or an accumulation of factory dust on it.
Thoughts?
Looking for Coefficient of Friction for Base Rail
Re: Looking for coefficient of friction for base rail
