Extruder feed roller wear
Because the extruder is made of metal and has high hardness, it is subjected to vibration, impact and other combined forces during production and operation, resulting in the formation of gaps in the parts and causing wear. The traditional repair methods include surfacing welding, thermal spraying, electric brushing, etc., but several methods have certain disadvantages: surfacing will cause the surface of the part to reach a high temperature, causing deformation or cracking of the part, which affects the dimensional accuracy and normal use. In severe cases, it will also lead to fracture; although the brush crossing has no thermal influence, the thickness of the crossing layer should not be too thick, the pollution is serious, and the application is also greatly restricted. Western countries mostly use polymer composite methods to address the above-mentioned problems. Its comprehensive performance and features that it can be machined at any time can meet the requirements and accuracy of use after repair, and it can also reduce the shock and vibration that the equipment bears during operation and prolong its service life. Because the material is a "variable" relationship, when an external force impacts the material, the material deforms and absorbs the external force, and expands and contracts with the expansion and contraction of the bearing or other components, and always maintains a tight fit with the components to reduce the probability of wear. In view of the wear and tear of large extruders, "molds" or "matching parts" can also be used to repair damaged equipment on site, avoiding the overall disassembly of the equipment, ensuring the matching dimensions of parts to the greatest extent, and meeting the production and operation requirements of the equipment.
The processing size of the bushing in the feeding section of the extruder does not match
When the material of the extruder bushing is 38CrMoAlA, due to machining reasons (the positioning keyway and the mating part are not on the same axis), there will be a matching gap between it and the side plate (material 40Cr or 45). When starting up and running, Glue leakage is caused by the recoil of the rubber material. The temperature does not exceed 100°C. The company has used other products to repair it before, and it can only be used for 1 to 2 days. The use of polymer materials can solve the problem very well.
The thread of the side cover of the feeding section of the extruder is damaged (slippage)
In the process of pre-tightening the bolts of the extruder, the bolts are deformed due to the tensile stress, and its recovery stress makes it tightly connected with the sealing part it is connected to, and it is lengthened with time and partially deformed. It becomes permanent deformation and the recovery stress drops, which leads to stress relaxation and torque drop, resulting in bolt loosening, causing sliding wire wear of the thread, and even damage to the internal thread of the fastened component in severe cases. The repair is carried out by using Mega Wah polymer materials, which have the retreat that metals do not have, and ensure the recovery stress after repair and ensure the use effect of the components. At the same time, the non-metallic nature of the material itself makes it far more astringent than metal, preventing re-damage caused by loosening and ensuring the safe and continuous production of the enterprise.
