Submerged arc welding pipe welding squeezing roller adjustment

In the production of high-frequency welded, the shaped state of the seam directly affect the quality of the welded tube, wherein the parallelism of the abutting surfaces of the welded joint is particularly important. The seam welding in the steel process, the main reduction by adjusting the squeezing rollers and the roller gap between the rollers to ensure that the degree of the parallel on two of the commissure. Welding the welding characteristics of the squeeze roll grooved extrusion pressing on the frame between the radii of the grooved rollers squeeze rolls other than about 10% larger, and therefore, the squeezing rollers and the roller surface of the outer pipe of circular cross section over creating a gap, the gap known as the "heel gap." In the actual molding, the pipe can not be perfectly circular cross-section. Under normal circumstances, due to the deformation of the strip edges is not sufficient, Peach section was easy, if not adjusted butt weld surface is not parallel to form a butt, seriously affecting the quality of the weld. If the upper squeeze roller and the other using the same pass squeeze roller radius reduction amount when the adjustment by the squeeze roller removes the V-shaped commissures, on the outer surface of the roller pressing the roller against the surface of the pipe will strongly on the tube surfaces likely to cause injuries, and the formation of a more serious V-shaped seam.

Pipe wall thickness, the higher the strength of the material, V-shaped when welding is not easy to eliminate the commissure. If the roller surface on the outside of the roll has caused a significant but still can not achieve an indentation shaped commissure I described adjustment has reached the limit, proceed to the next on the pressure roller will not only cause serious indentation, but also a more severe V-shaped butt seam. The ideal value of the roll gap with the tube wall thickness and strength of the various and different. For example, when the thin wall thickness generally requires the the roll gap is set smaller in order to increase the stability of welding. As the wall thickness is thick, even if the appropriate expansion of the roll gap, it will not affect the stability of welding. Therefore, when the thick-walled high-strength steel or molded in order to obtain greater "gap followed by" on the expansion of the roll gap and the practice, as long as it does not affect the stability of the expansion of a suitable welding.

In the high-frequency modulation type and welding pipe, through the contact surface and the heating mode and butt seam state relations analysis, using the adjustment of welding squeeze rollers roll gap and reduction methods, accurate and timely manner to ensure the steel plate welding edge welded to achieve a good state. When the I-shape commissure when instructions at this time in a substantially parallel state of the abutment surfaces during welding, does not require adjustment of the extrusion pressure roller; commissures when V-shaped abutment surfaces instructions at this time in the welding process, the lower portion of the first contact surface, can increase the amount of reduction rollers squeeze rolls to achieve an I-shaped state; when the inverted V-shaped commissures, the abutting surfaces described case the welding process, the upper surface of the first contact, by reducing squeeze roll reduction amount reaches the I-shaped state.