Bolts instead of an axle in a roller drum...?

Question

Can two bolts at both sides be used instead of an axle in a roller drum? The current setup has two ball bearings mounted on a stepped axle on both the sides of the drum. Will the two bolts setup damage the bolts or the drum? Is there a reason why an axle is used instead of bolts? Only reason I can think of is to ease removal of the bearings using the stepped part of the axle. If somebody can provide a explanation with a diagram of pressure points etc that be great. You can email me at khurdp at yahoo.

thank you,
Prasad

Answer 1

*An axle bolt has a shaft with a pair of opposed ends. An axle passage extends within the shaft and a transverse passage extends radially outwardly from the axial passage. A head attached to one end of the shaft has an outer face. A recess extends in from the outer face and the bottom of the recess is in communication with the axial passage. A lubrication fitting in the recess has one end in communication with the bottom of the recess and another end designed to be connected to a lubrication device. The recess in the bolt head is sufficiently deep that the second end of the lubrication fitting is within the recess and does not extend beyond the outer face.
Pl. click:
http://www.supertractor.com/bolts.htm

Answer 2

The obvious advantage of the an axle is that you'll get less wobble if the roller drum is heavily loaded. But bolts will work, although they may cause more wear on the whole system in the long-run.

To see why, consider the axle first; weight and centripetal force act on the axle/drum connection point. But with an axle, the force bows the entire axle, which causes less flex and thus less connection point wear than would a bolt with similar diameter and material. The bolt, on the other hand, under loading, will tend to enlarge the connection point with wear.

But, if your drum is not heavily-loaded in comparison to the specs of your bolts, you can get away with it. One thing that helps very much in these cases is to enlarge the contact are with the bolt head and the side of the drum through stacks increasingly larger washers, and a keyed slot, if possible.

Answer 3

I'm assuming that you are talking about removing the section of the axle that passes thru the drum, and bolting an axle section to each end of the drum, with each axle supported by it's own bearing?

If that is what you are talking about, I believe there will be a little difficulty in aligning the bearing shafts properly.

Also you may have difficulty in designing the end plates of the drum to be stiff enough to carry the alternating bending loads imposed on them by the weight of the loaded drum, as it rotates. With the shaft running thru the drum, the shaft acts as a support beam and carries the bending load that would otherwise be transmitted to the end plates in the proposed design.