3rd Party Inspection for Steel Structure
This content is general regarding the extent of inspection normally required for structural steel work supplied piece small or for partially assembled structures. The content may be used for platforms, ladders, hoppers, ducting, pipe track support systems, overhead transmission line, support pylons, frame sections of buildings. All steel structure inspection and tests are carried out against the approved drawings, purchase order specifications, purchasers or company standards, and within the practices and rules of the country, state or province and any government decrees, laws, ordinance or regulation as may apply. The applicable codes and specifications for the steel structure which is under construction process are:
Design code Purchase order specification Purchaser's standards Approved drawings And the applicable codes and standards is: ANSI/AWS D1.1. ANSI/AWS D1.5. EN 1090-2 AISC The applicable codes and standard may be based other international standards such as BS 449 and etc. Required Documents for Third Party Inspector Review:
The list of documents normally is agreed in the Pre Inspection meeting which is hold several weeks before actual commencement of inspection work. The parties which are participated in this meeting are manufacture, purchaser and third party inspection agency representatives. These are the list of documents which are normally agreed to be presented to the inspector:
Steel Structure Manufacture Quality Control Plan Steel Structure Inspection and test plan Steel Structure Data Sheet Steel Structure Approved Drawings Steel Structure Strength calculation sheets Steel Structure Material Test Reports Steel Structure Welding Specification Procedures (WPS) and Procedure Qualification Records (PQR) Steel Structure Conformity Certificates for fastenings Steel Structure Welders Qualifications Reports Steel Structure NDE procedures Steel Structure NDE Personnel qualifications Reports Steel Structure Calibration Certificates for Test Equipment Steel Structure Preparation and Painting Procedure Steel Structure Packing and Shipping Procedure Steel Structure Packing List Third Party Inspection for Steel Structure - Material Inspection The first actual inspection work in the Steel Structure is raw materials inspection. The Original or authenticated copies of mill certificates normally are available at the manufacturer’s premises. These are examined for compliance with the appropriate specification. The third party inspector examines these certificates for compliance with specifications and where appropriate, drawings. The review includes checks on: Certificate No. Heat or cast No. Chemical composition. Mechanical properties. Heat treated condition. NDE applied and results. Then the inspector witnesses the material identification on the certificates against marking. It is also necessary to check with steel structure drawing datasheet, material list and other specification as appropriate. Visual inspection for surface finish and probable defects need to be done and dimensional compliance with specification need also to be controlled. When third party inspector carried out the material inspection, then provides inspection visit report, the report contains following items: Confirmation of satisfactory document review Record of the endorsement of certification reviewed/witnessed Record of all non-conformities Record of any tests witnessed and the result Third Party Inspection for Steel Structure - Fabrication When the Steel Structure material inspection carried out and result was satisfactory or non-conformities closed by remedial action, then Steel Structure manufacture will be authorised to start fabrication. The third party Inspector checks following points on Steel Structure based on the inspection and test plan (ITP) which is already agreed between purchaser and Steel Structure manufacture. The inspection scope is determined in ITP, some clients prefer to have stringent control and put the TPI inspector in more “hold points” in fabrication activities and some others may take lesser “hold points” and put TPI much more in the review document. This depend to the inspection budget which client assign for inspection, much more inspection will have much more costs and less risks and conversely less more inspection will have less costs but more risks. For more detail review Inspection and Test Plan for Steel Structure article. There is draft ITP in this article which I believe it is the best practice for Steel Structure inspection. Third Party Inspection for Steel Structure - Welded Structure The third party inspector controls following points while production continues: Cleanliness and fit up of weld preparation Tacking up welds of good appearance Welding process approved Welders properly qualified Test coupons compiled where necessary NDE procedures properly applied and approved Completed weld profiles are acceptable If third party inspector is not in the hold or witness point in these stages, then will review steel structure quality control report in his coming visit or in final inspection day. Third Party Inspection for Steel Structure - Bolted or Riveted Structures The third party inspector controls following points while production continues: Dimensional check on pre-drilled parts Correct fastening being used Trial assembly of sub-structures If third party inspector is not in the hold or witness point in these stages, then will review steel structure quality control report in his coming visit or in final inspection day. Third Party Inspection for Steel Structure - Rust Prevention/Painting Inspection After completion of all fabrication the painting process is started under supervision of third party inspector, the inspection is done based approved procedure. Following points are taken in account while the structures are under painting process: Items have been prepared for coating as per specification requires Proper records of surface preparation and coating build up have been kept Paying particular attention to drying times/times between coats. Painted surfaces are free from drips, runs and bare areas. Dry film thickness measurements are checked. If third party inspector is not in the hold or witness point in these stages, then will review steel structure quality control report in his coming visit or in final inspection day. Third Party Inspection for Steel Structure - Final Inspection A final random inspection on quantities and visual appearance is necessary to be done by third party inspector on finished materials. Third Party Inspection for Steel Structure - Reporting Third party inspector provides Inspection Visit Report (IVR) after each visit as well as a final report summarising the activities carried out during the steel structure production in accordance with the contract requirements and circulated within the time limits specified in the contract. The report is in the format required by the client and clearly indicates final acceptance or rejection of the steel structure. Third Party Inspection for Steel Structure - Release Note: When required by the contract or purchase order a release note is issued by third party agency and given to the manufacturer when the steel structure have been finally accepted. Third Party Inspection for Steel Structure Packing, Marking and Shipping: The following points are checked by the third party inspector: Cleanliness of components Proper rust prevention for all machined surfaces Protection of protruding parts Shipping and other marks Third Party Inspection for Steel Structure Documentation When necessary the documentation package is reviewed and endorsed by the third party inspector.