THE INFLUENCE OF DESIGN CONDITIONS ON THE FAILURE OF THE UNIVERSAL CROSS JOINT (UCJ) OF THE CARDAN COUPLING

Abstract

In the system of power transmission from the driving to the operating machine, cardan couplings are components of vital importance. Due to the ability to transmit power over long distances, as well as insensitivity to the coaxiality of the connecting shafts, they have found wide application in all branches of mechanical engineering. In the plant for the production of profiled semi-finished steel products, a volumetric failure of the sleeve on the universal cross joint (UCJ) of the cardan coupling occured. This type of failure occurs very rarely with cardan couplings. In order to understand the real reason for the failure of the sleeve, analytical and numerical models were formed, and tests of materials and fracture surfaces were carried out. The influence of the line load distribution at the mating surfaces and the geometric stress concentration on the load capacity of the UCJ was analyzed using the developed models. With the increase in the unevenness of the line load distribution, the influence of tangential stresses on the stress state in the critical cross-section significantly increases. It is concluded that the simultaneous influence of the uneven line load distribution and the geometric stress concentration led to the failure of the UCJ sleeve.