The technique of automated applying of polymer coatings used for repair of tractor parts

Abstract

Restoration of case parts of machines significantly reduces the cost of their repairing. The present paper proposes a method for restoring case parts using the repair size method. Depending on wear degree, the fitment holes are bored to three repair sizes. The prepared hole is inserted with a new bearing, the outer ring of which is covered with a polymeric coating of the appropriate thickness ensuring the fixity of the joint. As a result of theoretical studies, the model was obtained for the formation of a uniform polymer coating on the outer surface of a rotating cylindrical part. The facility and technological equipment were developed for applying a polymer coating of F-40C elastomer solution onto the outer surface of the rotating bearing. The facility includes screwing lathe 1K62, centering drift pin, bath and magnetic holder MV-V. The holder is designed for mounting a bath filled with polymer solution and its plunging movement when rolling bearings are immersed in polymer solution. The drift pin serves for centering and assembling bearings. The assembled drift pin is inserted into the chuck of the machine rotating the pin when applying polymer coating. The screwing lathe 1K62 is equipped with an INNOVERT frequency converter of H3400A05D5K type, which allows adjusting infinitely the spindle speed from 0 min-1. The paper presents the results of experimental studies on the F-40C elastomer shrinkage, the parameters of the mode of immersing parts into its solution, the dependence of the geometric parameters of the formed polymer coating on the components of application and adhesion modes for polymer coatings based on F-40C elastomer solutions of different viscosity. The acceptable thickness of the polymer coating of elastomer F-40C on the bearing 209, ensuring the non-failure operation of the restored seating with a cyclic radial load of 20 kN is 0.1 mm.