Precision Inspection of Used Okamoto Surface Grinders
Used Okamoto Surface Grinders are widely used for finishing precision parts. Ensuring their accuracy and functionality requires systematic inspections covering geometric accuracy, motion performance, and workpiece machining quality.
Geometric Accuracy Assessment
Geometric accuracy forms the foundation of machine performance. After proper leveling, inspect the spindle system using a dial indicator and standard mandrel to measure radial runout and axial play. Check the worktable flatness with a precision level using a grid method, and ensure the guideways and grinding head movements are parallel. Evaluate the vertical feed accuracy of the grinding head with a dial indicator to confirm ball screw and guide rail clearance remains within acceptable limits.
Motion Accuracy Evaluation
Motion accuracy testing focuses on dynamic stability. Operate the worktable under no-load conditions to detect crawling or unusual noises. Check smoothness across the motion range and verify that the hydraulic system and guideway lubrication are functioning correctly. Confirm the grinding head positioning accuracy and repeatability through multiple cycles. Dynamic balancing of the grinding wheel is essential to prevent vibrations that affect machining quality.
Workpiece Accuracy and Test Cuts
Assess overall machine performance through test cutting. Use standard blocks for rough and finish grinding according to Okamoto’s process. Measure flatness, parallelism, and surface roughness, comparing results to factory standards. Identify issues such as burn marks, surface waviness, or dimensional deviations, linking them to spindle runout, coolant flow, or wheel selection.
Flexible Judgment and Economic Considerations
Evaluation criteria should consider equipment model and application. Geometric deviations should not exceed 50% of factory standards; motion accuracy must be normal; workpiece quality must meet surface and dimensional requirements. Factor in repair costs, machine age, and component replacements to assess the economic feasibility of purchasing and operating the used grinders.
In conclusion, Used Okamoto Surface Grinders require structured inspection and evaluation across geometry, motion, and workpiece accuracy. Following these standards ensures operational reliability, precise machining, and informed procurement decisions.