304 stainless steel round head cross head screw with gasket Computer chassis motherboard screw with built-in gasket screw

Screws and bolts are common connecting fasteners, with thread diameters ranging from less than one millimeter to hundreds of millimeters or even larger. The vast majority of threaded connections require pre tightening during assembly, with the aim of enhancing the rigidity, tightness, anti loosening ability, and preventing sliding of bolted connections under lateral loads. The pre tightening force is determined based on the force acting on the bolt group and the working requirements of the connection. For important threaded connections, it is necessary to calculate and control the pre tightening force.

The application range of oil pumps is very wide. When in use, it is necessary to assemble the oil pump. During the assembly process, when the pin is inserted into the pin hole, it is usually done by the operator using a hammer and aiming at the top of the pin to press it into the hole. Due to the high tolerance requirements for the depth and side clearance (the gap between the pin and the groove wall) of the pin, Traditional operating methods not only result in high scrap rates and longer personnel training times, but also slow processing speeds that affect production efficiency.

The pin and the pin inserted on the pin, the width of the pin gradually decreases from the insertion end to the other end, and there is also a protrusion on the pin, which is a triangular ratchet tooth shape. The pin is provided with a socket, and a pawl corresponding to the protrusion is set inside the socket.

Key connection is a typical mechanical connection method, usually used to connect parts on a shaft and provide circumferential fixation and torque transmission. Key connections can be divided into flat key connections, semicircular key connections, wedge key connections, and tangential key connections. Flat key connections are widely used in practical engineering due to their simple structure, good alignment, and convenient manufacturing. During operation, torque is transmitted through contact between the side of the key and the side of the shaft groove and hub groove. To ensure transmission accuracy, the flat key structure generally adopts a transitional fit. Due to its structural characteristics and working conditions, it is difficult to use ordinary mechanical tools for lifting during the maintenance process. If forcibly disassembled, it will damage the key and matching shaft.

In some embodiments, the rivet fixing mechanism includes a left moving block, a right moving block, a return spring, and a bracket. The left moving block and the right moving block are both movably installed on the bracket, and the left moving block and the right moving block are connected through the return spring. The insertion nozzle can extend between the left moving block and the right moving block, and support the left moving block and the right moving block. The left moving block is provided with a left half hole, The right moving block is equipped with a right half hole that matches the left half hole. Therefore, when the insertion nozzle is not inserted, the left and right moving blocks can be combined with the reset spring to fix and position the rivet by combining the left and right half holes into one hole. When the insertion nozzle is inserted, the left and right moving blocks will be pushed open by the insertion nozzle, separating the left and right half holes, so that the rivet can no longer be fixed and can be inserted with the movement of the insertion nozzle.