Welding process

A welding process for end connection of a first tube to a second tube along a circumferential joint by means of a weld bead, said method comprising the steps of:

• arranging the first and second tubes in a relative position for allowing formation of the circumferential joint;
• pushing a heat sink into at least one member selected from the group consisting of the first tube and the second tube;
• moving the first and second tubes and a welding burner relative to one another along the circumferential joint for producing the weld bead and thereby weld the first and second tubes by the welding burner;
• and
• emitting coolant from the heat sink at predefined intervals for cooling the member in an area of an end of the member as the first and second tubes are welded together.

A welding process for end connection of a first tube to a second tube along a circumferential joint by means of a weld bead, said method comprising the steps of:

• arranging the first and second tubes in a relative position for allowing formation of the circumferential joint;
• and
• moving the first and second tubes and a welding burner relative to one another along the circumferential joint for producing the weld bead and thereby welding the first and second tubes with a plurality of layers of the weld bead by holding the welding burner in a first welding position to produce a first layer and holding the welding burner in a second welding position to produce a second layer,
• wherein the first welding position differs from the second welding position with respect to a position of a burner tip in relation to a null position, in which the burner tip is arranged vertically above an uppermost apex point of the first and second tubes, and/or a position of a longitudinal axis of the welding burner with respect to the horizontal.