Fabrication
Web of built-up members are made of two web plate segments that are butt welded using full penetration welds. Flanges of built-up members that are made of two or more plate segments are connected by using full penetration butt welds.
Built-up members are made of two flanges and one (tapered or constant depth) web that are assembled and continuously fillet welded, on one side only, in an Auto Welding Machine, using a Submerged Arc Welding process to produce semi-fabricated members. The desired lengths of hot rolled sections are achieved by cutting 12m long pieces or by perpetually welding pieces. Perpetual welds are full penetration butt welds.
Hot Rolled members are cut to length and holes are punched in them or drilled using an automatic beam processor to produce semi-fabricated members. Semi-fabricated built-up or hot rolled members are then fitted with end plates, stiffener plates, gusset plates etc. (as required) and then manually welded to produce fabricated members.
Procedure Flowchart
Sand Blasting & Painting
Fabricated built-up and hot rolled members are shot blasted to Swedish standards up to SA 2.5 all built-up and hot rolled sections are painted epoxy, alkyd, PVDF or galvanized as per customer specification. Surface preparation (SA 2.5) typically specified for high performance coating for conditions like chemical spills and fumes, high humidity and proximity to salt water.
Furthermore, as per specification, hot rolled sections are painted with the help of state-of-art automatic painting machine.