LSAW Steel Pipe with Flanges
Our Allland company could also process the LSAW steel pipes with flanges,or weld the lifting eyes on the pipes according to the requirement of the clients.
The Processing of pipe and flange welded connection
① the flange contact surfaces should be pressed by metal processing, in order to prevent welding deformation, flange contact surface should be recessed into the depth of h = (0.10 ~ 0.20) t, to provide pre-deformation, shown in Figure 24.
② steel tubular wire welding of fillet weld connections, multi-layer welding, welding should be continuous, each bead surface should be cleaned, if found quality defects, should be removed after re-welding.
③ pressure flange contact surface roughness of less than or equal to ± 0.20mm, in order to ensure the flange connection, the contact surface bonding rate is greater than or equal to 75%, with a 0.4mm feeler, the insertion depth of the area and shall not be greater than 25% of the total area, connecting the maximum gap no larger than 0.8mm.
④ blue oval gold plate inner process diameter equal to or less than 0.03 ~ 0.1mm (tolerances according to 11) to consider the impact steel oval tolerance, the inner diameter of the flange processing to enlarge the balance + 0.4 ~ 1.0mm, an inner diameter of fillet weld groove greater than or equal to 45º, groove height h≥0.7t (see Figure 25)