How is a bowed turbine vane inspected and repaired if possible?

• A. By visual inspection only; replacement recommended
• B. By using X-ray to assess; welding repair
• C. By measuring with calipers only; replacement required
• D. By inserting a thickness gauge under the leading and trailing edge; it can be repaired by straightening if the material will permit

Answer: (D)

Assessing a bowed turbine vane comes down to measuring how far the blade has deviated from its intended shape and whether there is enough remaining material to support safe straightening. Using a thickness gauge under the leading and trailing edge directly quantifies the bow at critical points, giving a clear indication of the blade’s deformation and remaining section thickness. If those readings show the bow is within repairable limits and there are no cracks or other damage, the vane can be straightened with proper fixtures and controlled force, then rechecked to ensure the final geometry and thickness meet specifications. If the bow is excessive or damage is present, replacement is required. Visual inspection alone can miss internal issues; X-ray helps detect cracks but doesn’t determine repair feasibility; calipers alone won’t capture the bow profile accurately.