By: John W. Davis, P.E.
Crane surveyors are often faced with the problem of determining the sufficiency of structural repairs. Some jurisdictions require that the surveyor declare that the crane is in “safe working condition” as a requirement for acceptance or certification. In addition to the regulatory requirements, every surveyor is faced with the challenge of risk management. In practical terms, the surveyor must consider and avoid the risk of accepting a structural repair the sufficiency of which cannot be determined by visible inspection or load testing as is offered by ASME B30 standards.
The first thing to consider is who authorized the repair. The surveyor should require a copy of written directions by the authority that is qualified to allow and/or define the repair method. Some jurisdictions require that the repairs be authorized by the crane manufacturer or a registered engineer. The surveyor is left with the decision as to the validity of the authorizing agent.
The surveyor should be satisfied that the material used in the repair is the same as or equivalent to the original material. The material or the specification for the material may be supplied by the original equipment manufacturer. Alternatively, the proper material can be determined by a laboratory analysis of the parent material together with a certified test report with a mill test report from the repair material supplier.
If welding is part of the repair, the welding process should be prequalified or the welding process should be certified in accordance with AWS D1.1 standard. The joint design should be in accordance with the AWS D14.3 standard and the instructions of the authorizing authority. The welding must be done by a welder certified for the process, material, and welding position(s) used. The electrode material must be compatible with the parent material. The welds should be done in accordance with AWS D14.3 and be inspected in accordance with AWS D1.1 standard.
In general, the surveyor should require sufficient documentation to verify that the repair has been completed in accordance with the instructions of the authorizing agent. This assurance should include a parent material specification, a material certification for the repair material, a welding procedure certification (if needed), a welder certification document, and a Non-Destructive Evaluation report. The surveyor should load test the element(s) repaired and provide a document to attest to the satisfactory test results.
In summary, the crane surveyor should require sufficient documentation for his files to verify that the repair has been done in compliance with the instructions of the authorizing agency.