RU65805U1 - DEVICE FOR ARGON-ARC WELDING OF PIPES FROM METAL SHEET - Google Patents

Abstract

The utility model relates to a technology for producing welded pipes with a wall thickness of less than 0.3 mm, operating under conditions of high pressures, temperatures and aggressive environments.

A device for argon-arc welding of pipes from a metal sheet comprises a body made in the form of a metal bar, on the working surface of which there is a longitudinal groove in which the metal insert is placed, and means for attaching the end sections of the sheet to the body. A regenerative cooling channel is made in the beam of the hull along its entire length, and under the liner there is a trench, the cavity of which is connected to an inert gas system. The specified cavity through a plurality of nozzle holes made in the body of the liner is connected under the welded edges of the sheet

The proposed utility model can be used in any industry, especially in the manufacture of multilayer metal bellows.

Description

Technical field

The utility model relates to a technology for producing welded pipes with a wall thickness of less than 0.3 mm, used mainly in multilayer bellows expansion joints operating under conditions of high pressures, temperatures and aggressive environments.

State of the art

A device is known for manufacturing a tube from a metal sheet, including a welding table on which plates are fixed to the copper gasket using rulers. When welding plates, shielding gas is supplied simultaneously to the welding head and microchamber. In this case, the protective gas washes the outer surface of the parts to be welded, (see ed. Certificate of the USSR No. 2988444, MKI V23K 9/16, 1971). This technical decision is taken as an analogue of the proposed utility model.

However, in such a device there are no means for cooling the weld during the welding process, which leads to overheating of the edges of the elements being welded and the unstable existence of a common weld pool, burning through of thin-walled elements and marriage. In addition, this device is designed for welding thin-walled pipes of large diameter.

It is also known a device for argon-arc welding of pipes from a metal sheet, including a housing made in the form of a metal bar, on the working surface of which a longitudinal groove is made in which a metal insert is placed, and fasteners to ensure that the end sections of the sheet are pressed tightly against their insert. In this device, shielding gas is supplied to the area of the edges to be welded only from the welding head (see book. K.N. Burtsev “Metal Bellows”, Mashgiz, Moscow, 1963, p. 123). This device is taken as a prototype.

The prototype has the same disadvantages as the technical solution for the author. testimonial. No. 298444. In addition, this device does not have a body cooling system and a protective gas supply system under the weld. All this leads to overheating and oxidation of the weld during argon-arc welding. However, this device allows you to weld metal tubes from a sheet of different thicknesses, large and small diameters.

Utility Model Disclosure

The objective of this utility model is to create a device for welding pipes from a metal sheet, which solves the issue of cooling the lining and the body during welding and protecting the back of the weld from oxidation.

The technical result consists in preventing oxidation of the edges of the welded parts and, accordingly, preventing burn-through of thin-walled elements.

This problem is solved due to the fact that in the device for argon-arc welding of pipes from a metal sheet containing a body made in the form of a metal bar, on the working surface of which there is a longitudinal groove in which a metal insert is placed, and means for attaching the end sections of the sheet to the body , a regenerative cooling channel is made in the beam of the body along its entire length, and under the liner there is a groove, the cavity of which is connected to an inert gas system, in addition, the specified cavity through a plurality of nozzles x holes made in the body of the liner, is connected under the welded edges of the sheet.

Other differences of the proposed device is:

- the implementation of a metal liner of copper or copper alloys, which is attached to the timber using punching;

- the nozzle openings are zigzag along the length of the liner relative to its midline.

Brief Description of the Drawings

Figure 1 presents a top view of the working surface of the beam.

Figure 2 presents a section along aa of figure 1.

An example implementation of a utility model.

A device for argon-arc welding of pipes from a metal sheet comprises a housing 1 made of timber 2, on the working surface of which there is a longitudinal groove 3, in which the metal insert 4 is placed. Fastening of the insert 4 to the timber 2 is carried out by several punchings 5. The beam 2 is mounted on two supports 6 spaced along its length. A groove 7 is made in the beam 2, which is located under the liner 4, the cavity 8 of which is connected through the nozzle 9 to the inert gas supply system (not shown). In the insert 4 there are made nozzle openings 10 located along its entire length in a zigzag shape relative to its midline.

The regenerative cooling channel 11 is made in the beam 2. This channel 11 is connected to the water cooling system (not shown) through the inlet and outlet pipes, respectively 12 and 13. The regenerative cooling channel 11 is presented in

in the form of a rectangular groove 14, made from two sides of the beam 2 and from the end. These grooves 14 are closed by plates 15 and hermetically sealed. The workpiece sheet 16 is secured with clamps 17.

The operation of the device.

Before welding, the sheet blank 16 rolled into a tube is put on a beam 2 and fixed with clamps 17 on the surface of the insert 4. Water is supplied to the regenerative cooling channel 11 through the supply pipe 12 from the cooling system. The cavity 8 of the groove 7 is connected to an inert gas system. In the process of welding, shielding gas is simultaneously supplied from the torch to the side of the weld and nozzle holes 10 under the welded edges. As a result of this, the protective gas argon flowing out from the nozzle openings 10 enters the space from the back of the edges and forces air out, thus protecting the back of the weld from oxidation and overheating, which eliminates burn-through of thin-walled edges of the weld. In addition, this solution allows you to increase labor productivity, since the working surface of the beam is cooled during the welding process, so it takes less time to weld the next workpiece.

Industrial application

The proposed utility model can be used in any industry, especially in the manufacture of multilayer metal bellows.

Claims (3)

1. Device for argon-arc welding of pipes from a metal sheet, comprising a body made in the form of a metal bar, on the working surface of which there is a longitudinal groove in which the metal insert is placed, and means for attaching the end sections of the sheet to the body, characterized in that in the bar the housing along its entire length, a regenerative cooling channel is made, and under the liner there is a trench, the cavity of which is connected to an inert gas system, while the specified cavity through a plurality of nozzle openings filled in the body of the liner, connected under the welded edges of the sheet. 2. The device according to claim 1, characterized in that the nozzle holes are zigzag along the length of the liner relative to its midline. 3. The device according to claim 1, characterized in that the metal insert is made of copper or copper alloys and is attached to the beam of the body with a few pitches.