Subcontractor shall ensure that transferring of heat number/trace No. of material is done prior to cutting. Marking shall be done using soft nosed, low stress stamps.The marking shall be on location to easy visible avoid hire location or out lineInspection and acceptance by Contractor QC inspector and Owner representative may be required prior to cutting of any materials. Fit UpSubcontractor Supervisor shall submit fit-up inspection request to QC inspector and a copy to Contractor/Owner for arrangement time before checking.All fit-up inspections shall be conducted by Subcontractor QC inspectors and when require shall be checked by Contractor and Owner Representative.All joints shall be checked in conformance to the shop drawings and welding procedure specification.Preparation of weld edges shall be thermal cutting or machining. Wherever practicable, thermal cutting shall be done with a mechanically guide torch. For thermal cutting, the cut surfaces shall be ground to bright metal. The edges preparation shall be visually checked for any lamination and defect at the cut and ground edges. Any lamination or defect observed shall be removed by grinding.Design and tolerances of weld groove shall be in accordance with the approved WPS and AFC Drawings requirement. However, in general, the groove shall be beveled to give an included angle of not less than 60º for single and double V and not be less than 30º for single and double bevel. The root opening shall not be less than 1,6mm and the root face shall not be less than 01mm for single side without backing.Tacking work shall only be done by qualified welders and be performed with the same qualified welding procedure, as that will be used for fabrication welds. Consumables used for tacking shall be the same as per the qualified WPS.The depth of tack welds shall be proportioned to the load carrying requirements and restrain of the connectionTack weld for structural joints shall minimum of 50mm (02 inch) for plates thicknesses up to and equal to 30mm and longer for plates greater than 30mm. Tack weld shall be sufficient and equally space to prevent the tack weld form cracking. These tack welds shall be cleaned by grinding before actual welding commences.For fit-up of piping (line-up clamp shall not be used for butt welds in piping System, strong back and welded lugs are not permitted) or tubular connection, the internal and external transition shall be in accordance to the AFC Drawing and Company specifications.The alignment and dimension of the material to be welded shall be checked during fit-up inspection. The offset at structural butt joint shall not exceed T/10 (where T is the thickness of the thinner material) or 03mm, whichever is less. The offset of the longitudinal seams shall not exceed T/10 or 03mm, whichever is less. The offset or misalignment of the abutting pipe ends of a same nominal thickness shall not exceed 1.5mm. For joints of unequal pipe ends thickness, the external offset shall not exceed 03mm and internal offset shall not exceed 1.5mm. All offset or misalignment greater than 02mm shall be machined or ground to 1:4 taped transition.
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