ANALYSIS OF WEAR OCCURRENCE AND REPAIR METHOD OF TRACTOR WHEEL DISCS
Livestock buildings with a residual resource turned out to be in high demand by small and medium-sized businesses in the countryside. Reconstruction is carried out, as a rule, in an economic way for modern mechanized distribution of feed by tractor units. However, approximate construction calculations of the parameters of the transformed building and without taking into account the parameters of the kinematics of the tractor unit lead to reduced indicators for the width of the driveways (passages) inside the building, and they, in turn, lead to intensive wear of the side surface of the tires and wheel discs on concrete bumpers. Exactly the same picture is observed in modern compacted buildings of residential microdistricts of cities, where intensive wear of the undercarriage components of communal tractor units is also observed. The situation is significantly complicated by the lack of domestic small-sized tractors with a traction class of 6.0 and 9.0 kN. The use of 14 kN traction class tractors instead will also require an even larger aisle width. The article presents the theoretical prerequisites for the occurrence of wear, proposals to designers and builders on the calculation of passages and turning zones of tractor units. A method is proposed for eliminating wear and strengthening the wheel disks by welding a ring made of a steel bar. For the rear discs, a bar with a section diameter of 18 mm is required, for the discs of the front wheels, a bar with a diameter of 14 mm is recommended. Welding to the worn rim is carried out from both sides of the bar; it is possible both by manual arc welding and by semi-automatic welding in a shielding gas environment. During welding, it is recommended to check the disc runout directly on the tractor. Subject to the recommendations and sequence of welding, radial runout is possible within 8 ... 12 mm, lateral runout - up to 15 mm. To prevent shearing of the chamber spool body, it is proposed to weld an insert in the form of a thin-walled cylinder to the disc mounting hole. The measures taken to strengthen the disks of the front and rear wheels of a tractor directly operated on farms made it possible to increase the resource by approximately 1.6 ... 1.8 times compared to the resource of new discs.