Frequently Asked Questions
Precautions
Construction personnel must wear solvent-resistant gloves, safety goggles, and dust masks to prevent materials from coming into contact with skin or inhaling dust.
Remaining materials must not be returned to the original packaging and shall be disposed of in accordance with hazardous waste management regulations, categorized accordingly.
After repair, the equipment must undergo a 30-minute no-load trial run, during which temperature and vibration levels should be monitored. It can only be put into normal operation once it has been confirmed that there are no abnormalities.
Through the above-mentioned procedures, rapid repair of bearing seats can be achieved, restoring their mating accuracy and load-carrying capacity. The repair cost typically ranges from 30% to 50% of the cost of replacing the part with a new one, making it suitable for emergency equipment repairs or the reuse of older components.
Remaining materials must not be returned to the original packaging and shall be disposed of in accordance with hazardous waste management regulations, categorized accordingly.
After repair, the equipment must undergo a 30-minute no-load trial run, during which temperature and vibration levels should be monitored. It can only be put into normal operation once it has been confirmed that there are no abnormalities.
Through the above-mentioned procedures, rapid repair of bearing seats can be achieved, restoring their mating accuracy and load-carrying capacity. The repair cost typically ranges from 30% to 50% of the cost of replacing the part with a new one, making it suitable for emergency equipment repairs or the reuse of older components.
Quality inspection and assembly of the assembly
Before assembly, apply a thin layer of grease (such as lithium-based grease) to the repaired surface. Use either a cold-fit method or heat the bearing (oil temperature ≤120℃) for assembly, and avoid striking the coated surface.
Quality inspection and final inspection of assembly
Visually inspect the coating surface for porosity, cracks, and depressions. Use a plug gauge or internal diameter gauge to verify dimensional accuracy; the fit clearance must meet design requirements (e.g., the interference fit between the bearing and its housing should be 0.01–0.02 mm).
Perform dynamic balancing tests (for high-speed rotating components) to ensure that coating uniformity does not affect the operational stability of the equipment.
Perform dynamic balancing tests (for high-speed rotating components) to ensure that coating uniformity does not affect the operational stability of the equipment.
Finishing and Dimensional Control for Post-Processing and Precision Restoration
Using precision grinding or honing processes, the inner diameter of the bearing seat shall be machined to the designed dimensions (with tolerances conforming to the H7/g6 fit requirement). The surface roughness shall be Ra ≤ 1.6 μm. During measurement, multiple points must be inspected (at least 3 cross-sections) to ensure that the roundness is ≤ 0.005 mm.
The chamfered areas shall be machined to an R0.5–R1.0mm radius to avoid stress concentrations caused by sharp corners.
The chamfered areas shall be machined to an R0.5–R1.0mm radius to avoid stress concentrations caused by sharp corners.
Rough machining for post-processing and precision restoration
After curing is complete, use a lathe or internal cylindrical grinder to remove the machining allowance. The cutting speed should be controlled within the range of 80–120 m/min, and the feed rate should be set at 0.05–0.1 mm/r. This will help prevent chipping of the coating caused by excessive cutting forces.
Spraying/scraper coating operations for coating application
Spraying Method: Use a high-pressure airless sprayer (with a nozzle diameter of 0.8–1.2 mm) or an air spray gun to apply the coating evenly along the axial direction of the bearing area. Control the thickness of each layer to between 0.05 and 0.1 mm, with an interval of 5–10 minutes between layers (adjust according to the material’s curing speed). Allow an additional machining allowance of 0.1–0.2 mm in the total coating thickness.
Preheating treatment for coating application (as required)
If the ambient temperature is below 15℃, preheat the substrate at a low temperature (60-80℃) to remove surface moisture and accelerate the coating curing process. Avoid direct flame heating, which could cause localized overheating.
Surface pretreatment for preliminary preparation and surface treatment
The inner surface of the bearing seat is roughened by sandblasting (using white corundum sand with a recommended grit size of 80–120 mesh) to remove the oxide layer and create a uniform, rough surface (surface roughness Ra 2.5–5 μm), thereby enhancing the adhesion of the coating.
After sandblasting, use compressed air (dry and oil-free) to blow clean the surface, removing any sand particles and dust. If necessary, wipe the surface with anhydrous ethanol to ensure it is completely dry and clean.
After sandblasting, use compressed air (dry and oil-free) to blow clean the surface, removing any sand particles and dust. If necessary, wipe the surface with anhydrous ethanol to ensure it is completely dry and clean.
Surface inspection and evaluation for preliminary preparation and surface treatment
Use a caliper and dial indicator to measure the inner diameter, roundness, cylindricity, and surface roughness of the bearing seat. Record the amount of wear (e.g., if unilateral wear exceeds 0.1 mm, repair is required).
Use penetrant testing (PT) or magnetic particle testing (MT) to inspect the base material for defects such as cracks and porosity. Repair may proceed only after confirming that there is no structural damage.
Use penetrant testing (PT) or magnetic particle testing (MT) to inspect the base material for defects such as cracks and porosity. Repair may proceed only after confirming that there is no structural damage.
Preparation and Surface Treatment: Disassembly and Cleaning
Disassemble the component to be repaired, and use specialized tools (such as pullers and wrenches) to separate the bearing and associated components, taking care not to damage the base structure.
Use kerosene, gasoline, or ultrasonic cleaning to remove surface oil stains, rust, and impurities. Pay particular attention to cleaning the inner bore of the bearing housing, chamfers, and mating surfaces, ensuring that no residual contaminants remain.
Use kerosene, gasoline, or ultrasonic cleaning to remove surface oil stains, rust, and impurities. Pay particular attention to cleaning the inner bore of the bearing housing, chamfers, and mating surfaces, ensuring that no residual contaminants remain.
Product Inquiry：
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