Quality assurance in the assembly of wheel pairs of railway wagons by the thermal method

Abstract

In the process of forming the wheel pair with the help of the press, mechanical damages of the joined surfaces appear, which reduce the fatigue strength and reliability of the wheel pair. Assembly of the labyrinth ring and internal rings of the bearing with the axis is carried out without the use of force by heating them and free putting on the axle, which excludes damage to the surface of the axis. After putting on the of the axis of the labyrinth rings and inner rings of bearings, for the subsequent assembly of the knot, they must be cooled to a temperature that differs from the ambient temperature by no more than 3 °C. Based on the analysis of the operation of the production lines for the assembly of wheel sets inrailway carriage plants, it was found that 120 seconds are required to comply with the required assembly cycle of the bearing rings, and 160 seconds for the labyrinth rings. Achieving such a cooling rate (100 °C for 120 seconds for bearing rings and 130 °C for 160 seconds for labyrinth rings) is difficult. The article analyzes the methods of forced cooling of the labyrinth ring and the bearing ring to accelerate the cycle of assembling the axle axleboxes of the wheel pair and the most effective solutions have been found to provide a cycle of qualitative assembly of the axleboxes unit of the wheel pair.