Requirement for Process of Manufacturing Long Life Bearing
Introduction
The purpose of this paper is to provide an overview of the process requirements for the manufacturing of long life bearings. Bearing reliability or lifetime of bearing is defined by the time period a bearing can perform its intended function before reaching a degree of wear to be replaced. Long life bearings, by definition, are bearings that can perform its intended purpose for a long period without requiring maintenance or replacement. Manufacturing of bearings is a delicate process with stringent levels of process controls and quality assurance at each step to ensure that the bearing does not fail prematurely. This paper describes the design principles, process steps and control levels for the manufacture of long life bearings.
Design Principles
The design of any bearing involves thoughtful consideration of specific application requirements, materials selection and manufacturing methodologies to ensure that the bearing can perform its intended purpose without failure. Most bearing failures occur due to improper design that involves inadequate material selection, deviation from standard tolerances and insufficient rigidity of the components. Long life bearing designs should be carefully developed by incorporating application specific design factors, material selection based on operating environment, strenuous quality control processes during parts manufacturing and after assembling the bearings.
Process Steps
The manufacturing of long-life bearings is a complex process and involves several steps to ensure quality and reliability. The process can be divided into three stages:
# Material selection:
The raw materials used for manufacturing long-life bearings should be carefully selected depending on the operating environment. The materials used should be resistant to corrosion, wear, heat, impact and other factors that can cause premature bearing failure. Selection of raw materials should also consider the bearing operating temperature and load requirements to avoid premature failure.
# Machining:
Once the raw materials are selected, the components should be carefully machined to meet the dimensional and surface requirements. The machining process involves careful selection of cutting tools, workpiece fixturing, cutting fluids and cutting parameters to ensure accuracy and precision.
# Assembly:
The components should be assembled using special tools and jigs for accurate alignment and position. During assembly, proper lubricants should be applied to ensure proper functioning. Quality control tests should be performed at the end of the assembly process to ensure smooth operation, correct alignment and correct torque range.
Process Control and Quality Assurance
The manufacturing of long life bearings is a complex process with several tightly controlled processes to ensure reliable and durable performance. The process control and quality assurance involves the following steps:
# Process Documentation:
All processes should be thoroughly documented and maintained up-to-date to ensure repeatability. Documentation should also detail the tolerances and surface finishes for machining, heat treatment and assembly requirements for easy reference in case of queries.
# Statistical Process Control:
Statistical process control should be used to monitor and control the machining operations. Parameters such as surface finish, part dimensions, roundness, straightness, etc. should be compared to the specified parameters and deviations calibrated to the allowable limits.
# Material Traceability:
All the materials used in the manufacturing should be traceable with respect to origin, heat treatment and other parameters. This will help to identify the source of material should any issue arise during actual operation.
# Quality Assurance:
Stringent samples should be used during assembly operations to check parts accuracy and overall quality. Final inspection of the bearings should involve measuring the assembly runouts and part inspections using profilometer, coordinate measuring machine, shadow graphs etc.
Conclusion
Manufacturing of long life bearings requires close attention to detail and thorough process control through out the process. Bearing designs should involve careful selection of materials based on the application requirements. The machining processes should be closely monitored using statistical process controls to maintain the dimensional and surface requirements for the components. The assembly processes should involve stringent quality controls for alignment and control. The traceability of all raw materials through out the process and final inspection are important to ensure the reliability and durability of the finished products.
