×

Automatic arc-welding method

  • US 4,816,639 A
  • Filed: 07/14/1988
  • Issued: 03/28/1989
  • Est. Priority Date: 07/20/1987
  • Status: Expired due to Term
First Claim
Patent Images

1. In an automatic arc-welding method, which comprises:

  • continuously supplying a welding wire as a consumable welding electrode at a prescribed feeding rate substantially vertically through a nozzle toward a groove formed between two objects to be welded;

    continuously moving said nozzle together with said welding wire along the longitudinal direction of said groove; and

    supplying a prescribed welding current having a prescribed welding voltage to said welding wire to produce an arc between the tip of said welding wire and said groove, thereby welding said objects to be welded together along said groove by means of the arc heat;

    the improvement comprising by;

    when welding said objects to be welded together along said groove,(a) continuously measuring a distance of a root gap of said groove in the downstream of said nozzle in the travelling direction thereof;

    (b) calculating a target welding current (I), with which a depth of penetration agrees with a target value thereof, in accordance with the following formula (1);

    
    
    space="preserve" listing-type="equation">I=I.sub.o -KG (1) where,I;

    target welding current,Io ;

    welding current when the distance of root gap is zero,K;

    constant dependent on the depth of penetration, kind of shielding gas, the material of the welding wire and the like, andG;

    distance of root gap, and(c) controlling said welding current so as to agree with the thus calculated target welding current.

View all claims
  • 1 Assignment
Timeline View
Assignment View
    ×
    ×