What are the common issues associated with corrected 3D welding tables?

I. Precision Rebound and Deformation
This is the most common issue, typically caused by a failure to fully eliminate new stresses after the straightening process. Residual stresses generated during straightening gradually release, causing flatness and hole position accuracy to drift again after 1–2 months. This is particularly prevalent in products that underwent mechanical straightening without subsequent low-temperature tempering; the probability of precision rebound exceeds 60%, with a typical magnitude of 0.02–0.05 mm.

II. Risk of Material Damage
Damage from flame straightening: Improper temperature control can lead to localized overheating and grain coarsening, reducing material strength in the affected area. If water cooling is used on cast iron welding tables, surface micro-cracks are highly likely to form, which can easily propagate and cause structural failure under load.
Damage from mechanical straightening: Excessive pressure can cause localized indentations on the table surface, compromising flatness. Thin panels may also develop hidden internal delamination, affecting overall structural rigidity.

III. Reduced Fit Accuracy of Locating Holes
Deformation of the table surface during the straightening process can cause slight distortion in the locating holes. This leads to difficulties in inserting locking pins or results in excessive clearance, thereby reducing clamping and positioning accuracy. In severe cases, holes may need to be reamed and custom-fitted with new pins, incurring additional machining costs.

IV. Damage to the Anti-Rust Coating
Straightening operations (hammering, applying pressure, or heating) can damage the table's original anti-rust coating. If not promptly recoated, localized rusting is likely to occur. This rust can spread into the locating holes, accelerating wear on the hole walls and ultimately reducing positioning accuracy and service life.