SPECIFICATION AND STANDARD FOR STRUCTURAL STEELWORK: GENERAL PART 7 - WELDING

1.10.1       General

1.10.1.1    All metal on metal welding shall be done in accordance with BS EN1011 and AWS D1.1.    Spot  welding  of  cold-formed  steel  sections  shall  also  conform  to  the requirements outlined in the above standard.

1.10.1.2    All butt welds shall be full penetrations unless noted otherwise.  All fillet welds shall be 6mm continuous unless noted otherwise.  All welds shall be chipped free of slag.

1.10.2       Welding Electrodes

1.10.2.1    Electrodes shall be of approved types conforming to AWS D1.1 and shall be kept in a dry store in unbroken packets.

1.10.3       Details of Welding Procedures

1.10.3.1    The general procedures for shop and site welds and other details shall be submitted in writing, in accordance with AWS D1.1, to SCI for approval before fabrication.

1.10.4       Approval and Testing of Welding Procedure

1.10.4.1    The Contractor shall carry out welding procedure tests in accordance with AWS D1.1, to demonstrate by means of a specimen on a steel representative of that to be used that he can produce satisfactory welds with the proposed welding procedure.

1.10.5       Approval and Testing of Welders

1.10.5.1    The Contractor shall satisfy SCI that his welders are suitable for the work upon which they are employed.  Welders working to approved welding procedures shall satisfy the relevant requirements of AWS D1.1.

1.10.6       Measurement of Weld Sizes

1.10.6.1    The Contractor shall provide gauges necessary for the measurement of weld sizes.

1.10.7        Site Welding

1.10.7.1    No site welding shall take place unless shown in the Shop Drawings or otherwise approved. Where site welding is required or permitted the Contractor shall submit details of staging, platforms and weather protection for welders and materials. Site welding shall be subject to all the requirements of welding as defined in this section of the Specification.

1.10.8       Quality of Weld

1.10.8.1    All welds shall be visually inspected as per AWS D1.1. All non-destructive testing shall  be  as  per  AWS D1.1.  Any  weld  with  defects  greater  than  the  maximum permitted as in the Code shall be liable to rejection.

1.10.9       Frequency of Testing

1.10.9.1    Visual Inspection

All welds are to be visually inspected.

1.10.9.2    Selection of Welds to be Examined

1.10.9.3    Where  there  is  a  requirement  for  less  than  100%  examination,  the  method  of selection of welds to be examined is to be agreed with the Engineer before the commencement of work.

1.10.9.4    Where examination reveals unacceptable defects in a joint, two additional joints in the group represented by the joint are to be examined. If the results on these two additional joints are acceptable then the original weld may be repaired and re- examined by similar means.

1.10.9.5    If the non-destructive examination of the two additional joints reveals unacceptable defects, examine each joint in the group.

1.10.9.6    The cost of testing, examining and repair of welds that fail to meet the specified requirements shall be borne by the Contractor.

1.10.9.7    Welded connections made on circular hollow sections

The interface on steel plates, steel sections and steel hollow sections which are to be welded to circular hollow sections shall be machine reamed so that the reamed edges match perfectly with the curvature of the CHS at the connections. Thermal cutting of the steel plates, steel sections and steel hollow sections to produce the desired profile at the mating surfaces is not acceptable.

1.10.10     Inspection Authority

1.10.10.1  The examination of welds shall be carried out by approved personnel from the accredited laboratory engaged by the Contractor.