Large Pipe Internal Longitudinal Welding Machine for Oil Gas Pipeline

Same as the previous product of large pipe tack welding machine, The Large Pipe internal longitudinal welding machine of this section also has very long total length and even longer. So, it is very hard to take a general view of the machine, only a local sectional view as attached.

    1.     Role of Large Pipe Internal Submerged Arc Welding Machine:

   1)      Short for Large Pipe internal SAW machine, this equipment is located at the second half stage of the production line for producing large diameter longitudinal submerged arc welding pipe which is used in the deployment of Oil and gas pipeline;

   2)      We mentioned this Oil gas pipeline production line in the former two products of “Heavy duty Edge Milling machine” and “Large Pipe Tack Welding machine” for its equipment constitution and workpiece specification;

   3)      Process Technology in the Large Pipe internal longitudinal welding Machine:

    a)      Plate is sent and have its both sides edge milled with the heavy duty plate beveling machine;

    b)      The edge milled pate is sent to pre-bending machine to be bent into the shape of circular arc;

    c)      The pre-bent plate is sent to 2000Ton Press Brake to be bent into a nearly round pipe with only 100mm gap left;

    d)      The pipe is sent to Large Pipe Tack Welding machine to be final closed into round shape and tack welded;

    e)      The tack welded pipe is sent to this Large Pipe internal welding machine for carrying out large pipe internal longitudinal submerged arc welding;

    f)      The internal welded pipe is sent to Large pipe external welding machine for external large current submerged arc welding;

    g)      The welded pipe is sent to Large pipe rounding machine for final rounding;

    h)      The rounded pipe is sent to Hydrostatic Test machine for testing;

    i )      The tested pipe is sent to Ultrasonic testing station

Thus finish the production of Large diameter longitudinal welding pipe.

    2.     Operating of Large Pipe Internal Longitudinal Welding Machine:

    1)      This Large Pipe internal SAW machine has similar working principle as Welding Manipulator in terms of pipe internal welding;

    2)      However, because of much larger and especially longer pipe to be welded, the structure of this large pipe internal welding machine is completely different from that of the welding manipulator. Please check attached picture;

    3)      During work, the workpiece of large and long pipe (20~ 30m long) sits on its supporting rack in stationary status;

    4)      A set of welding head extends from the opposing side of the workpiece and travels into the pipe, until reaching the internal terminal of the pipe at far end;

    5)      From here, the welding head starts on its SAW process together with its retreating from the pipe, until it welds to the other end of the pipe (near end) and totally retreated from internal of the pipe, thus finishing the job of large pipe internal longitudinal submerged arc welding;

    6)      Due to its heavy duty, this Large Pipe internal welding machine adopts with Triple Arc in its submerged arc welding process. The welding current is 400 ~ 500A, with 4mm welding solid wire;

    7)      Because the SAW is performed at inside of the large pipe, where people can not get access, video monitor is used to track the welding process.

    3.     Parameter of Large Pipe internal submerged arc welding Machine: