BANGLADESH POWER DEVELOPMENT BOARD TENDER ... - BPDB

18.5 Materials And Workmanship18.5.1 Structural Steel(1) GeneralStructural steel, bolts and nuts shall comply with the requirement of an approvedstandard and this Specification in all respects and those shall be fabricated fromhot rolled sections unless other wise specified or agreed in writing by the Board.(2) MaterialsThe materials to be used shall be free from harmful defects and rust. Samples ofmaterials shall be tested, and copies of the test reports giving physical andchemical properties shall be submitted to the Board for approval. The Contractorshall carry out all necessary tests, at his own expenses, to prove that thematerials offered for the intended purpose are in compliance with the approvedStandard.In lieu of these tests, mill sheets issued by the authorised manufacturers will beacceptable. The characteristic strength of the structural steel shall have thefollowing values regardless of the standard and code used: -a. Yield Point : not less than 2400 kg/sq.cmb. Tensile Strength : not less than 4100 kg/sq.cmc. Elongation : not less than 20%(3) Bolt and Shear ConnectorHigh strength bolts, anchor b6lts, ordinary bolts and shear connectors to besupplied for the erection of structures shall conform to the Standard approved bythe Board and shall be of an approved manufacturer. Specially devised highstrength bolts, if used, shall tightened in accordance with the manufacturer'sinstructions. Any bolt that has been fully, tightened and then un-tightened shallnot he used in the permanent Works.(4) FabricationFabrication and erection drawings shall be submitted to the Board for approvalprior to commencement of any fabrication and erection work. Steelwork shall befabricated to the required details in a manner approved by the Board. TheContractor shall provide adequate facilities for the Board to inspect materials andfabrication works in the shop and at the Site when required.(5) WeldingWelding of structural steel shall be performed to the required type and size by anelectric arc process by qualified welders under approved conditions. The plant,equipment and the adopted testing and inspection method shall conformgenerally with the relevant approved standard and other details in thisSpecification and shall all be to the satisfaction of the Board.Welding shall not be performed when the ambient temperature is less than 0 degGhorasal 200 MW to 300 MW Gas Turbine Peaking Power Plant Project (Vol-2 of 3)196