Straight seam steel pipe is widely used in various industries, such as petroleum, metallurgy, construction, coal mine, port, machinery and other industries. During the installation and use of straight seam steel pipes, there are strict technical requirements, which should be carried out according to actual conditions and operating specifications to ensure the safety and quality of straight seam steel pipes. In the normal use process, the following points need to be paid attention to:
1. Construction preparation before installation of straight seam steel pipe
The pipeline trench should be dug in accordance with the requirements of the drawings. After the bricking of the pipeline well is completed, the various types of straight seam steel pipes required have arrived, the quality is intact and the inspection is qualified. The required construction tools, including electric welding machines, cutting machines, Electric hammers, polishers, etc. are fully prepared, and installation can only begin after a series of preparations have been made.
2. Installation process of straight seam steel pipe
Locate the pipeline according to the design of the drawing, prefabricate the pipeline bracket according to the site situation, then cut the material according to the design and site, then grind the bevel with a polisher, and then weld. When welding, the strip is sent to the pipe welding unit, which is rolled by multiple rollers, and the strip is gradually rolled up to form a round pipe blank with an open gap.The reduction amount of the squeeze roller is adjusted so that the gap of the weld is controlled at 1 ~ 3mm, and the two ends of the weld are flush. If the gap is too large, the proximity effect will be reduced, the eddy current heat will be insufficient, and the welding between the grains will be poor, resulting in unfusion or cracking. If the gap is too small, the proximity effect will increase, and the welding heat will be too large, which will cause the weld to burn out; or the weld will form deep pits after extrusion and rolling, affecting the surface quality of the weld.
3. Inspection of installation quality of straight seam steel pipe
(1) Welding pipes must not be welded at the welds, and there should be no welds at the bends.
(2) The deviation of vertical pipe installed per meter shall be less than 3mm, and the deviation of horizontal installation shall be less than 1mm.
(3) The surface quality of the straight seam welded pipe should be smooth, and no defects such as folding, cracking, delamination, and overlap welding are allowed. Minor defects such as scoring, scratches, misplaced welds, burns, and scarring on the surface of straight seam tubes must not exceed negative deviations in wall thickness.
