I. On-Site Correction Situations: Overall Tilting or Support Imbalance
When the platform exhibits a sloping deformation with one end higher than the other, it is usually caused by uneven installation foundation, uneven stress on support legs, or improper tightening. These problems can be directly leveled on-site.
1. Preparation
Use an electronic level with an accuracy of at least 0.02mm/m to ensure reliable measurement. Thoroughly clean the table surface before adjustment, removing oil, welding slag, and other debris. Avoid operation in direct sunlight, strong winds, or equipment vibration environments, and maintain a stable workshop temperature.
2. Correction Steps
Loosen all anchor bolts or support shims to release pre-tightening stress, allowing the platform to be in a free state.
Measure each direction with the level along a "X" shaped path (two diagonals + four side centerlines), recording the bubble offset value in each direction.
Based on the "three-point plane determination" principle, prioritize adjusting the three main support points: first adjust the long side to center the bubble, then adjust the short side, making cross-adjustments until the readings in all directions are basically consistent.
After adjustment, evenly tighten all fixing bolts to prevent secondary deformation due to unilateral stress.
3. Re-measurement and Confirmation: After tightening, remeasure to ensure the flatness is restored to ≤0.10mm/1000mm (precision-grade standard) before re-use.
📌 Warm Reminder: If the platform is equipped with an electronic leveling system, more precise fine-tuning can be performed using the digital display interface.
II. Severe Deformation Requiring Professional Repair: Local or Structural Damage
If the test shows a central bulge, edge depression, saddle shape, drum shape, or torsional deformation, it indicates that the platform body has undergone plastic deformation and must be repaired by a professional manufacturer using specialized techniques. On-site correction should not be attempted.
1. Manual Scraping Repair: For high-precision platforms (e.g., flatness requirements ≤0.05mm/1000mm), manual scraping is the gold standard for restoring accuracy. This involves applying red lead to a standard flat plate and rubbing it to expose high points. These high points are then removed point by point with a scraper, repeating the "scraping-grinding" operation until the contact points are evenly distributed (at least 20 points per 25×25mm²). This method achieves sub-micron level precision and creates oil-retaining micro-pits on the surface, resulting in superior wear resistance.
2. CNC Precision Milling Repair: For platforms with large areas of minor deformation or after welding repairs, a large gantry milling machine can be used for overall precision milling. After fixing the platform, it is aligned using the back reference surface, and a disc milling cutter is used for one-pass machining. This method is highly efficient and can quickly restore flatness to within 0.08mm/1000mm.
3. Vibration Aging + Mechanical Correction
If the deformation is caused by residual stress release, vibration aging treatment is required first to redistribute and attenuate internal stress. Then, hydraulic equipment is used to slowly apply pressure to the protruding parts for leveling, avoiding material damage. This method is suitable for the overall alignment of large cast iron platforms.
III. Key Actions After Correction
1. Re-testing Verification: After repair, use a coordinate measuring machine or laser interferometer to re-inspect, ensuring the data meets standards and issuing a formal report.
2. Establishing Accuracy Archives: Archive each inspection data, draw a "flatness change trend chart," predict the next correction cycle, and achieve preventative maintenance.
3. Strengthening Daily Maintenance: Clean weld slag after each welding to avoid localized corrosion; conduct a basic level check quarterly to prevent problems before they occur.
⚠️ Special Reminder: If clamp insertion/removal jamming, positioning misalignment, or weld misalignment is found, the machine should be stopped immediately and the flatness checked to prevent batch workpiece scrapping.
