I. Product Introduction

When rolling mill bearings reach their design service life or develop fatigue spalling on raceways, they are not necessarily limited to being treated as scrap steel. NMT remanufacturing services restore used bearings to near-new precision and load capacity through systematic inspection, repair and performance restoration processes, at significantly lower costs than new products, extending the overall service life of bearings.

 

Definition of Remanufacturing: NMT remanufacturing is not simple cleaning and re-lubrication, but involves removing fatigue layers from raceway surfaces through precision grinding to restore raceway geometric accuracy and surface quality; simultaneously replacing rolling elements and cages with new components of the same specifications; and重新 performing clearance matching and precision inspection. Remanufactured bearings can achieve 95% to 100% of new product accuracy and load capacity.

 

Difference Between Remanufacturing and Repair: Conventional bearing repair typically only addresses visible damage locally and does not guarantee performance restoration. NMT remanufacturing执行 the same quality standards as new products, conducting comprehensive inspection and systematic restoration of bearings, with each remanufactured bearing undergoing complete precision inspection and performance verification.

 

Applicability of Remanufacturing: Suitable for four-row tapered roller bearings and four-row cylindrical roller bearings with fatigue spalling, wear or indentations on raceways. Bearings with severe corrosion, cracking or cage pocket damage require inspection and evaluation to determine remanufacturing feasibility.

 

II. Core Product Advantages

Significant Cost Effectiveness: Remanufacturing costs are only 40% to 60% of new bearing purchase prices. For a large hot roughing mill four-row tapered roller bearing set, remanufacturing can save users hundreds of thousands of RMB in procurement costs. Within the same equipment operating cycle, the cost per unit time of remanufactured bearings is significantly lower than new products.

 

High Performance Restoration: NMT remanufactured bearings achieve 95% to 100% of new product accuracy and load capacity. Remanufactured bearings meet new product standards in installation dimensions, rotational accuracy and clearance parameters, and can be directly installed and used in original equipment positions.

 

High Resource Utilization Efficiency: Remanufacturing preserves the main ring material of the original bearing, avoiding the significant energy consumption of re-melting, forging and heat treatment processes. Compared to manufacturing new bearings, remanufacturing can reduce carbon emissions by more than 80%, making it an effective means of resource circular utilization.

 

Shortened Procurement Cycle: New bearing procurement cycles are typically 3 to 6 months. Remanufacturing delivery cycles are generally 4 to 6 weeks, significantly reducing waiting time for bearing replacement and reducing the risk of equipment downtime due to bearing shortages.

 

Possibility of Multiple Remanufacturing: As long as bearing ring material thickness allows, NMT remanufactured bearings can undergo multiple restoration cycles. Each remanufacturing removes one layer of fatigue material through precision grinding, and bearings can continue to be used with slightly reduced dimensions.

 

III. Typical Application Scenarios

Renewal After Bearings Reach Design Service Life——When rolling mill bearings reach design service life or show signs of fatigue spalling, NMT provides remanufacturing services. After bearings are returned to the NMT factory, they undergo cleaning and inspection, with the technical team evaluating remanufacturing feasibility. Remanufactured bearings are returned to site for reinstallation and use, with performance接近 new products and significantly reduced usage costs.

 

Repair After Accidental Bearing Damage——When bearings sustain localized damage from偶然 factors (foreign object ingress, lubrication interruption, impact overload, etc.), NMT provides targeted repair services. After inspection confirms the scope and depth of damage, NMT restores bearing performance through processes including grinding to remove damaged layers, replacing rolling elements and cages, and重新 matching.

 

Optimization of Bearing Spare Parts Reserves——For critical stands with high downtime losses, users typically need to储备 spare bearings. Remanufacturing can serve as a supplementary approach to spare parts management——restoring used bearings to performance through remanufacturing and holding them as spare parts, meeting emergency replacement needs at lower costs.

 

Systematic Refurbishment During Planned Shutdowns——During planned mill overhauls or extended shutdown periods, NMT can provide systematic remanufacturing services for multiple bearing sets. Through集中 inspection, batch repair and unified quality inspection, remanufactured bearings are ensured to be reliably ready for use after overhaul completion.

 

IV. Quality Assurance

Rigorous Inspection and Evaluation Process: Each used bearing arriving at the NMT factory undergoes systematic inspection and evaluation. Inspection内容包括: visual inspection and damage recording, key dimension measurement (bore, outside diameter, width, clearance), raceway surface quality inspection (cracks, spalling, indentations), and material hardness testing. Based on inspection data, the NMT technical team evaluates remanufacturing feasibility and determines processing plans.

 

Precision Grinding and Processing: The core process of remanufacturing is precision grinding of raceway surfaces. NMT uses high-precision grinding equipment to remove fatigue layers from raceway surfaces, with grinding allowance precisely controlled according to damage depth and ring wall thickness. Ground raceway surface roughness reaches the same grade as new products. Non-working surface dimensions of rings may change due to grinding but do not affect installation and use.

 

Complete Replacement of Rolling Elements and Cages: During remanufacturing, all rolling elements and cages are new. Rolling elements undergo precision screening and grading, with roundness error controlled within tight tolerances. Cages are re-manufactured to original specifications, with material and dimensions consistent with the original. This ensures that the rotational accuracy and load distribution of remanufactured bearings reach new product levels.

 

Clearance Re-Matching: Remanufactured bearings undergo new clearance matching. NMT recalculates and sets cold installation clearance target values based on user-provided mill parameters and operating conditions. Clearance matching is achieved through selection of inner and outer rings, adjustment of spacer ring thickness and other methods, ensuring that remanufactured bearings operate identically to new products after installation.

 

Factory Testing and Verification: After assembly, remanufactured bearings undergo the same factory testing procedures as new products. Testing内容包括: rotational accuracy testing, vibration testing, clearance re-measurement and visual inspection. Each remanufactured bearing set is accompanied by an independent inspection report recording key dimensions and precision parameters.

 

V. Product Range

NMT offers the following remanufacturing and full lifecycle services for steel metallurgical rolling equipment:

 

Four-Row Tapered Roller Bearing Remanufacturing: Suitable for four-row tapered roller bearings used in hot and cold rolling mill work rolls and backup rolls. Restoring bearing performance through grinding to remove raceway fatigue layers, replacing rolling elements and cages, and re-matching clearance.

 

Four-Row Cylindrical Roller Bearing Remanufacturing: Suitable for four-row cylindrical roller bearings used in mill backup rolls and continuous caster segments. Restoring bearing performance through grinding to remove raceway fatigue layers, replacing rolling elements and cages, and re-verifying配合.

 

Bearing Inspection and Evaluation Services: Comprehensive inspection of used bearings, assessment of remanufacturing feasibility, and issuance of inspection evaluation reports.

 

Bearing Operation File Management: Assisting users in establishing operation files for each bearing set, recording installation, maintenance, remanufacturing and usage data, providing a data foundation for full lifecycle management.

 

Spare Parts Reserve Solution Optimization: Providing remanufactured bearing reserve solution recommendations based on user mill configuration and maintenance plans.

 

VI. Brand Strength

NMT has accumulated sustained service experience and data foundations in rolling mill bearing remanufacturing and full lifecycle management.

 

Remanufacturing Technical Capability: NMT possesses complete remanufacturing processing capabilities, including raceway precision grinding, rolling element and cage replacement, clearance re-matching, precision inspection and performance verification. Remanufacturing processes执行 the same quality control standards as new products.

 

Accumulated Application Data: Through long-term provision of remanufacturing services for rolling mill bearings, NMT has accumulated data on bearing fatigue and wear characteristics under different operating conditions. Based on this data, NMT can more accurately assess the remanufacturing potential and remaining life of used bearings.

 

Full Lifecycle Service Philosophy: NMT regards remanufacturing as an important component of full bearing lifecycle management. From new product selection, installation guidance, operation and maintenance to remanufacturing reuse, NMT provides corresponding technical support at each stage of the bearing lifecycle, forming a complete service closed loop.

 

Practical Experience in Cost Effectiveness: NMT has accumulated economic data on remanufacturing under different mill types and operating conditions, enabling users to make more economical choices between “replacing with new products” and “remanufacturing reuse.”

 

VII. Global Collaboration

NMT provides rolling mill bearing remanufacturing and full lifecycle management services to steel mills, non-ferrous metal processors and metallurgical equipment manufacturers worldwide.

 

Service Reach: Remanufacturing services cover four-row tapered roller bearings and four-row cylindrical roller bearings used in various hot rolling, cold rolling, continuous casting and non-ferrous metal rolling equipment.

 

Collaboration Model: Users can return bearings that have reached design service life or sustained damage to the NMT factory for inspection, evaluation and remanufacturing. NMT can also provide long-term collaboration solutions including periodic inspection and remanufacturing recommendations based on user needs.

 

Technical Support: NMT provides comprehensive inspection evaluation reports after bearings are returned to the factory, and factory inspection reports after remanufacturing completion. NMT can provide remanufacturing solution consultation, spare parts reserve optimization recommendations and full lifecycle cost analysis services according to user needs.