| 摘要 |
FIELD: mechanical engineering; welding. ^ SUBSTANCE: invention can be used for submerged multiarc welding of large-diameter tubes. Proposed method includes striking of welding arcs, welding and sequential extinction of welding arcs at simultaneous reduction of welding rate. At beginning of welding, arcs are struck in turn at a distance from beginning of tube providing identity of initial part of weld seam as to depth of penetration, width and form, to indicated parameters of seam in zone of welding at steady-state conditions. In process of welding specific heat input of welding is maintained at constant level over entire length of seam. Welding arcs are cut off at distance from end of tube providing good quality of end part of seam without formation of end crater. Stricking and extinction of welding arcs is carried out at stepless regulation of their power and speed of electrode wire feeding. Values of power of welding arcs and speed of electrode wire feeding are set depending on speed of tube movement. ^ EFFECT: improved quality of seam at beginning and end of welding, reduced cropping of ends. ^ 1 ex, 1 dwg |
