Splined Shaft Design

[emery]

I need a good reference to help design 16'' to 24'' diameter, heavy duty sliding splined shafts for torque transmission in rolling mills. Can anyone help?

 

[ggarnier]

Have you looked at a company called (I'm working from memory here) Stoffel Polygon Systems? They apparently either have a patent or a capability lock on a system using a rounded triangular male/female system instead of the classic splined shaft.

I don't do power transmission at all, so I have only seen their ads and have wondered if they really offer an advantage.

 

[diamondjim]

You should give some torque values to have
any of this make any sense. What length
of spline is allowed?

 

[emery]

The torque value for a large ( 16'' to 26'') diameter splined shaft and hub is 582,000 ft-lb at 0 to 28.6 rpm. The machine is also reversible. The female spline can be any where from 20 " to 40 " long. This spline must slide a short distance (up to 1&quot when at full load. Where are design formulas available that address sliding spines of this size?

 

[diamondjim]

Emery,
582000 ft-lbs divided by a 1 foot pitch radius would give
you a tangential tooth load of 582000 lbs divided
by the number of teeth for the max tangential tooth
load per tooth of spline.
Number of teeth equals the DP time the pitch diameter

This could be treated as a special gear problem.
The Lewis Equation is W = SFY/DP
W equals the tangential tooth load
S equals approximately 200 times the BHN
F equals the face width or length
Y equals approximately .66 (guess for 30 degree spline)
DP is the diametral pitch of the gear or spline.

Smax equals approximately 500 time the BHN which would
be equal to the approximate UTS of the material.
So the above value is probably a good value for
max stall or braking tangential tooth load.

Is this approach clear? You might try punching in
different dp values and assume a 24 inch diameter and
4 inches length of interface for the f value. This is
a static approach and does not consider the dynamic
life of the parts.
shaft to get some values.

 

[malekmohammadi]

I WANT SOME PICTURES ABOUT SHAFTS AND KINDS OF THEM.

 

[gearguru]

Emery,
check the Machinery's Handbook. There is a good reference for both the dimensional and stress calculations of the inch-based involute splines.
These splines are also standardized in ANSI B92.I-1970.
When calculating the stresses, do not expect that all teeth will be carrying the load. (75% is what some sources recommend). Design of involute splines is close related to the gear design. More detailed info about your parts is needed for the actual design.
gearguru