Abstract
Advantages of ball or roller bearings on almost all types of operating mechanisms are stressed in this paper. There are not only the savings in power consumption, which frequently run from 25 to as much as 60 per cent, but also collateral advantages of varying description. Frequently the bearings permit operations which without them would be exceedingly difficult or expensive.
Some of the limitations to the use of the bearings are taken up, particularly those dealing with space limitations on equipment of old design. The concurrent development of heavy-duty bearings for steel-rolling-mill work along with backed-up types of rolling mills is traced at some length. Many features of operating conditions found in steel mills are discussed in their relation to the use of bearings of this type. Lubrication and care of the bearings are also given consideration.
How much load the roller bearing will carry and how long it will carry that load satisfactorily are not yet known. The whole field of roller-bearing uses on a large scale is in process of development, and ideas have not yet crystallized on many features of the work. In the present state of development they operate successfully under many varying conditions, but it is essential that they be adapted particularly to the work which they are called upon to do. The fact that wear is practically negligible permits maintenance of constant operating conditions for a much longer period than with plain bearings, and makes a strong point in favor of the anti-friction type. It seems to be generally accepted that in a great many cases, their greater initial expense is fully justified by the results to be expected from their use.
