A complete melt transmission gear pump is mainly composed of motor, reducer, universal coupling and pump head. Haike is a professional melt pump manufacturer in China, providing melt pumps including: plastic sheet melt pump, rubber extruder melt pump, low viscosity melt pump, etc.
There are two main reasons for gear breakage: the first one is that the gear will break when it is suddenly overloaded, no foreign bodies are found after disintegration, and from the point of view of the broken position in the root of the gear, the possibility of sudden overload breaking gear can be ruled out. The second reason is that the tooth is like a cantilever beam, and the bending stress at the root of the tooth is the maximum after loading, the size of the transition part at the root of the tooth has changed greatly, and the machining tool mark left along the width of the tooth has caused a certain degree of stress concentration. Therefore, when the gear is repeatedly loaded, Fatigue cracks will occur at the root of the tooth, and gradually expand, resulting in tooth fracture, which is the direct reason for the breakage of the driven gear of the melt pumping W wheel pump.
Fracture of the gear shaft: The fracture occurs at the transition between the gear teeth and the shaft. It is obvious that there is a greater stress concentration. When the driven gear shaft is subjected to repeated bending stress, fatigue cracks will occur at this place and gradually expand, leading to fracture of the gear shaft. The reason for the fracture and failure of the driven gear is that the lubrication condition of the sliding bearing becomes worse and the sliding bearing gradually bites to death and produces alternating bending stress and twisting stress, resulting in fatigue fracture of the root of the driven gear and the transition part between the shaft and the gear (i.e. the stress concentration action) under alternating bending stress and twisting stress. Crack.