Reasons for fixing the gearbox with a pressure plate around the gearbox
December 15, 2023
Modification of the installation of the gearbox. Actual condition of the mounting surface The gearbox and beam of the JD31-400 press are gray cast iron materials. The gear box is installed above the beam and is fixed by bolts. After long-term use, the screw holes on the beam are tripped. After repeated reaming and transposition drilling, the top surface of the beam is covered with screw holes and beams. Almost scrapped and the walls of the gearbox mounting holes are cracked.
The reason for the analysis is that the beam is gray cast iron, which is characterized by good compressive strength and poor tensile strength, but the brittleness is large. Here, the thread on the beam is easily brittle by the tensile force, and the machine tool has large working vibration, and the shaft diameter of the transmission shaft is the same. If the shaft is poor, the gearbox will be subjected to alternating stress, resulting in damage to the threaded hole.
The choice of solutions is common in similar equipment. The user's solution is to enlarge the screw holes, change the holes, and finally replace the new beams. Because the reaming must be disassembled, the machine tool is used for machining, the disassembly and assembly work is large, and the top surface of the beam has nowhere to drill. 2 The cost of replacing the beam is high, so it is necessary to change the way of thinking. Due to the poor tensile performance of the screw hole on the cast iron beam, the installation method is changed. The gear box is fixed around the gear box by the pattern conveyor belt pressure plate. The reasons are as follows: 1 The beam can be removed without using the magnetic drill to process the mounting hole; 2 The fixing hole of the pressure plate is outside the joint surface of the gear box and the side of the beam, so that the threaded hole on the beam can be prevented from being pulled or not overlapped with the original hole, and the contact surface between the pressure plate and the gear box is enlarged, so that the gear box is not installed by the gear. The cracking of the mounting hole of the box can also avoid cracking of the new mounting hole wall.