CN105522252A - Method for processing internal welding defects of straight-tube elbow combined tube fitting - Google Patents

Abstract

The invention belongs to the field of welding manufacturing processing, in particular to a method for processing internal welding defects of a straight-tube elbow combined tube fitting. The method comprises the following steps: 1) charging argon gas from one end of the tube fitting through an argon arc welding machine; 2) regulating the direction of the tube fitting, so that the charged argon gas completely covers a welding defect part; 3) pulling out a tungsten electrode from a spray nozzle of an argon arc welding gun until reaching the length of the internal welding defect part; 4) processing the welding defect part; and 5) stopping charging argon gas, recycling tungsten electrode into the spray nozzle, ending the method. According to the method, in a welding process, the repair work is smoothly completed due to absence of a factor of shielding sight line by the spray nozzle, a welded part is not required to be grinded, the process period is reduced, and the first repair pass yield through radiographic inspection is nearly 100%.

Description

A kind of straight tube bend-head combination inside pipe fitting weld defect processing method

Technical field

The invention belongs to welding manufacture process field, particularly relate to a kind of straight tube bend-head combination inside pipe fitting weld defect processing method.

Background technology

Instrument valve pipeline is all docked after welding completes by stainless steel bend and straight tube to be connected with valve instrument, this class component adopts the banjo fixing butt jointing form of complete penetraction and fusion in welding, this joint all adopts argon arc welding one side welding with back formation, by welder's technical ability and group confrontation quantitative limitation, be easy to form defect at the channel interior root of weld, through x-ray inspection, excessive defect will must not be had after having welded.Once generation excessive defect, joint saw opening or cleaning will be removed unnecessary weldering meat, then the welding of machining groove, one-period gets off quite very long, and repair for 1st time may not pass through, and causing manpower and materials wastes in a large number, seriously constrains project progress.

Summary of the invention

Technical problem to be solved by this invention is to provide a kind of straight tube bend-head combination inside pipe fitting weld defect processing method, long to solve the prior art processes cycle, the defect that repair rate is low.

The present invention for solving the problems of the technologies described above adopted technical scheme is:

There is provided a kind of straight tube bend-head combination inside pipe fitting weld defect processing method, its special character is: comprise the following steps:

1) argon gas is filled with by argon arc welding machine from pipe fitting one end;

2) adjusting pipe fitting orientation makes weld defect position be covered completely by institute's applying argon gas;

3) tungsten electrode is extracted from argon-arc welding gun nozzle the length to interior welds rejected region can be reached;

4) weld defect position is processed;

5) stop being filled with argon gas, reclaim tungsten electrode in nozzle, terminate.

The invention has the beneficial effects as follows: postwelding position is without the need to reconditioning, and process cycle is short, significantly improve through radiographic inspection repair for 1st time qualification rate.

Accompanying drawing explanation

Fig. 1 is schematic diagram of the present invention;

In figure: the direction of arrow is for being filled with argon gas direction; 1. argon-arc welding gun nozzle 2. tungsten electrode 3. interior welds rejected region 4. argon gas 5. straight tube 6. elbow

Detailed description of the invention

Below in conjunction with the drawings and specific embodiments, the present invention is described in detail.

Argon-arc welding gun can not stretch into fault location in pipe freely and repair as welding rod, and the guard space that during welding, the tungsten electrode of argon-arc welding gun leaves nozzle very short is oxidized, and lets alone and stretch into the reparation of tube interior fault location as welding rod.

Specific gravity of argon gas is greater than air, if be full of argon gas in the small space of welding region, argon gas can sink to bottom, and air is discharged formation one protection atmosphere, such welding gun also can weld even without nozzle.

As shown in Figure 1, the invention provides a kind of straight tube bend-head combination inside pipe fitting weld defect processing method, comprise the following steps:

1) argon gas is filled with by argon arc welding machine from pipe fitting one end;

2) adjusting pipe fitting orientation makes weld defect position be covered completely by institute's applying argon gas;

3) tungsten electrode is extracted from argon-arc welding gun nozzle the length to interior welds rejected region can be reached;

4) weld defect position is processed;

5) stop being filled with argon gas, reclaim tungsten electrode in nozzle, terminate.

Owing to not having the factor that nozzle blocks sight line to complete patch work smoothly in welding process, postwelding position, without the need to reconditioning, is reduced process cycle, and is reached intimate 100% through radiographic inspection repair for 1st time qualification rate.

Claims (1)

1. a straight tube bend-head combination inside pipe fitting weld defect processing method, is characterized in that: comprise the following steps:

1) argon gas is filled with by argon arc welding machine from pipe fitting one end;

2) adjusting pipe fitting orientation makes weld defect position be covered completely by institute's applying argon gas;

3) tungsten electrode is extracted from argon-arc welding gun nozzle the length to interior welds rejected region can be reached;

4) weld defect position is processed;

5) stop being filled with argon gas, reclaim tungsten electrode in nozzle, terminate.