Extruder failure and extruder feed roller wear solution
Extruder feed roller wear
Since the extruder is made of metal, the hardness is high, and it is subjected to vibration shock and other compounding forces during production and operation, resulting in gaps between the components and causing wear. The traditional repair methods include surfacing, thermal spraying, brushing, etc., but several methods have certain drawbacks: surfacing will cause the surface of the part to reach a very high temperature, causing deformation or cracking of the part, affecting dimensional accuracy and normal use. In severe cases, it will lead to breakage; although the brush crossing has no heat effect, the thickness of the crossing layer should not be too thick, the pollution is serious, and the application is also greatly limited. Western countries have applied the polymer composite method to the above problems. Its comprehensive performance and mechanical machining characteristics at any time can meet the requirements and accuracy after repair, and can also reduce the shock and vibration of the equipment during operation and prolong the service life. Because the material is a "variable" relationship, when the external force impacts the material, the material will deform and absorb the external force, and will expand and contract with the expansion or contraction of the bearing or other components, and always maintain a tight fit with the component to reduce the chance of wear. For the wear of large extruders, "mold" or "mating parts" can also be used for on-site repair of damaged equipment, to avoid the overall disassembly of the equipment, to ensure the size of the components to a greater extent, and to meet the production and operation requirements of the equipment.
Polymer material treatment extruder wear problem
The processing section of the feeding section of the extruder does not match the processing size.
When the material of the extruder bushing is 38CrMoAlA, due to machining reasons (the positioning keyway and the mating part are not on one axis), there is a matching clearance between the side plate (material 40Cr or 45), when starting up, Leakage due to the action of the recoil of the rubber. The temperature does not exceed 100 °C. The company has previously repaired other products, only 1 to 2 days, the use of polymer materials repair can solve this problem.
Extruder feed section side cover thread damage (sliding wire)
During the pre-tightening of the bolt, the bolt is deformed by the tensile stress, and its restoring stress is tightly connected with the sealing part to which it is attached, and is stretched over time, partially stretched and deformed. It becomes permanent deformation, and the stress is reduced. As a result, stress relaxation and torque drop occur, and bolt looseness occurs, causing the wire to wear the thread, and even causing damage to the internal thread of the fastened component. It is repaired with polymer materials, which has the concession of metal, which guarantees the recovery stress after repair and ensures the use of components. At the same time, the non-metallic nature of the material itself makes it more sturdy than metal, eliminating the damage caused by loosening and ensuring the safe and continuous production of the enterprise.
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