CN112620893A

CN112620893A - Method for realizing ultralow inter-lane welding temperature

Info

Publication number: CN112620893A
Application number: CN202011302940.8A
Authority: CN
Inventors: 孙吉宏; 缪旭弘; 叶开富; 周圣兵; 杜度; 张玮; 袁思鸣; 毛柳伟; 李杨; 彭茂林; 周广礼
Original assignee: People's Liberation Army 92578
Current assignee: People's Liberation Army 92578
Priority date: 2020-11-19
Filing date: 2020-11-19
Publication date: 2021-04-09

Abstract

The invention discloses a method for realizing ultralow inter-lane welding temperature, which specifically comprises the following steps: cofferdams are manufactured on the two opposite sides of the welding groove of the weldment in a cofferdam mode, and the heat exchange and dissipation positions of the cooling medium are limited in the cofferdams; meanwhile, cooling water is introduced into the cofferdam during welding. The invention solves the problems of poor heat dissipation effect and low weldment productivity existing in the existing low-temperature layer welding mode.

Description

Method for realizing ultralow inter-lane welding temperature

Technical Field

The invention belongs to the technical field of welding, and relates to a method for realizing ultralow interbay welding temperature.

Background

Control of the temperature between layers (often referred to as layer temperature) is a very important welding process technology. Carbon steel and low alloy steel with low carbon equivalent often have no strict technical requirements on the control of the layer temperature; however, in the welding occasions of various types of steel with high carbon equivalent and large restraint degree, because the crack sensitivity is high, and the crack is difficult to completely prevent under the condition of low layer temperature, the welding of the steel in engineering usually requires that the layer temperature is controlled within the range of 100-300 ℃, and the higher the carbon equivalent, the higher the restraint degree of the weldment (such as a large thick plate and an ultra-thick plate) is, the higher the layer temperature is. However, in the case of special process applications in which the carbon equivalent of the weldment is high and the hardenability is high, there are also applications in which it is required that the lower the layer temperature is, the better the layer temperature is, so-called "cold welding". In the prior art, a control method for realizing the ultralow layer temperature (in actual production, the layer temperature is regarded as the indoor temperature state as the ultralow layer temperature) includes: welding with high energy density, such as electron beam welding, laser welding and plasma beam welding; immersing part of the weldment in cold water; and thirdly, the weldment naturally radiates heat in the air, and the welding is continued when the low layer temperature is reached.

The welding technology for realizing the low layer temperature has the following limitations: in actual welding production and welding repair, due to the size and the thickness of a weldment, most weldments cannot use high-energy-density welding methods such as electron beam welding and laser welding at all; secondly, part of the weldment is immersed in cold water, so that the heat conduction stroke of the arc working part is long, and the heat dissipation speed is low; secondly, temperature rise of water temperature leads to temperature difference reduction, heat dissipation speed reduction and heat dissipation effect deterioration; and thirdly, the weldment naturally radiates heat (including forced air cooling) in the air, so that the productivity of the weldment is very low, the production period is long, and the production cost of the weldment is high.

Disclosure of Invention

The invention aims to provide a method for realizing ultralow inter-tunnel welding temperature, which solves the problems of poor heat dissipation effect and low weldment productivity in the conventional low-temperature layer welding mode.

The invention adopts the technical scheme that the method for realizing the ultralow interbay welding temperature specifically comprises the following steps: cofferdams are manufactured on the two opposite sides of the welding groove of the weldment in a cofferdam mode, and the heat exchange and dissipation positions of the cooling medium are limited in the cofferdams; meanwhile, cooling water is introduced into the cofferdam during welding.

The present invention is also characterized in that,

the conditions met when the cofferdam is arranged are as follows:

(1) the heat exchange and heat dissipation positions are arranged close to the molten pool;

(2) the water flowing area fully covers the welding seam area.

And for the revolving body weldment, hooping the silicone tube on the peripheral surface of the weldment to manufacture the silicone tube dyke.

Four silicone tubes are arranged, every two silicone tubes form a group, and the two groups of silicone tubes are respectively positioned at two opposite sides of the welding groove;

and manufacturing a silicone tube dyke after the two silicone tubes in the same group are hooped on the weldment, and forming a cofferdam between the two silicone tube dykes.

For non-revolving body weldment, the plasticine is adopted to manufacture the plasticine dyke.

The two plasticines are respectively positioned at two opposite sides of the welding line; each plasticine is made into a hollow rotary type plasticine dike, one end of the plasticine dike is provided with a water inlet pipe, the other end of the plasticine dike is provided with a water outlet pipe, and cooling water is filled in a cofferdam formed by the plasticine dike.

For the non-revolving body weldment, the dike is made of a water-impermeable material.

The invention has the following beneficial effects:

(1) the invention makes it possible to use traditional MAG/MIG method to control the low layer temperature in the remanufacturing of the most equipments which can not use the high-energy density welding method;

(2) in the manufacture and remanufacture of most industrial equipment, the welding operation of low-layer temperature control by using a submerged method is hardly possible (mostly due to the volume and the shape), and the invention provides the low-layer temperature control method which is easy to realize and low in cost;

(3) the invention completely overcomes the limitations of a natural cooling method that the welding productivity is very low, the production period is long and the welding production cost is high due to the natural heat dissipation of the weldment in the air.

Drawings

FIG. 1 is a schematic diagram of a cofferdam prepared by silicone tubes in the method for realizing ultralow inter-road welding temperature of the invention;

FIG. 2 is a schematic diagram of a cofferdam equipped with plasticine in an implementation of an ultra-low interbay welding temperature of the present invention;

FIG. 3 is a schematic diagram of the position of a cofferdam relative to a weld joint in the realization method of ultralow interbay welding temperature of the invention.

In the figure, 1, a weldment, 2, a welding groove, 3, a welding wire, 4, an electric arc, 5, a silicone tube dike, 6, cooling water, 7, a molten pool, 8, a water inlet pipe, 9, a water outlet pipe, 10, a welding line and 11, a plasticine dike.

Detailed Description

The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.

The invention relates to a method for realizing ultralow inter-road welding temperature, which specifically comprises the following steps: cofferdams are manufactured on the two opposite sides of the welding groove of the weldment in a cofferdam mode, and the heat exchange and dissipation positions of the cooling medium are limited in the cofferdams; meanwhile, cooling water is introduced into the cofferdam during welding.

The conditions met when the cofferdam is arranged are as follows:

(2) the water flowing area fully covers the welding seam area.

As shown in fig. 1, a silicone tube dyke 5 is produced by caulking a silicone tube to the outer peripheral surface of a rotor weldment 1. Four silicone tubes are arranged, every two silicone tubes form a group, and two groups of silicone tubes are respectively positioned at two opposite sides of the welding groove 2; the welding wire 3 is welded in the welding groove 2 by the arc 4, and a molten pool 7 is formed in the welding process.

And (3) hooping two silicone tubes in the same group onto the weldment, then manufacturing silicone tube dykes 5, forming a cofferdam between the two silicone tube dykes 5, and filling cooling water 6 in the cofferdam.

As shown in fig. 2 and 3, a plasticine dam 11 is formed from plasticine for the non-rotating body weldment 1.

The two plasticines are respectively positioned at two opposite sides of the welding seam 10; each plasticine is made into a hollow rotary type plasticine dyke 11, one end of the plasticine dyke 11 is provided with a water inlet pipe 8, the other end of the plasticine dyke 11 is provided with a water outlet pipe 9, and cooling water 6 is filled in a cofferdam formed by the plasticine dyke 11. The welding wire 3 is welded in the welding groove 2 by the arc 4, and a molten pool 7 is formed in the welding process. For the non-revolving body weldment, the dike is made of a water-impermeable material.

Example 1

The weldment 1 is a revolving body, and the welding groove 2 is a 360-degree circular welding line. 4 silicone tubes of 12mm diameter were tightened to the outer peripheral surface of the weldment 1 as silicone tube dikes 5. A cofferdam is formed between every two silicone tube dykes 5, and the width of the cofferdam is 40 mm. The dyke is 5mm away from the welding groove 2.

Placing the welding seam 10 operation section in a clock 1: 30 points to 3: at the 30 o' clock, running water (tap water) is from 1: 30 point position entering cofferdam, 3: and the flow is discharged from the position of 30 and the flow rate is 8L/min.

Using an austenite welding wire with the diameter of 1.0mm, welding current of 100 amperes and welding voltage of 20 volts to weld a first swing-free welding seam 10 in a 120 mm-long segmented welding seam area at the bottom of a welding groove 2 with preset pressure stress; stopping for several minutes after the first welding seam 10 without transverse swing is welded, measuring the surface temperature of the just-welded welding seam 10, continuing welding the second welding seam 10 when the surface temperature is not higher than the room temperature, and always circulating the steps; and after the first layer of the section is welded, rotating the weldment 1 to the symmetrical position of the section of the welding seam 10 to weld a second section of the welding seam.

Claims

1. A method for realizing ultralow inter-lane welding temperature is characterized by comprising the following steps: the method specifically comprises the following steps: cofferdams are manufactured on the two opposite sides of the welding groove of the weldment in a cofferdam mode, and the heat exchange and dissipation positions of the cooling medium are limited in the cofferdams; meanwhile, cooling water is introduced into the cofferdam during welding.

2. The method for realizing the ultralow interbay welding temperature according to claim 1, wherein the method comprises the following steps: the method comprises the following steps of; the conditions met when the cofferdam is arranged are as follows:

(2) the water flowing area fully covers the welding seam area.

3. The method for realizing the ultralow interbay welding temperature according to claim 1, wherein the method comprises the following steps: and for the revolving body weldment, hooping the silicone tube on the peripheral surface of the weldment to manufacture the silicone tube dyke.

4. The method for realizing the ultralow interbay welding temperature according to claim 3, wherein the method comprises the following steps: the number of the silicone tubes is four, every two silicone tubes are in a group, and the two groups of silicone tubes are respectively positioned on two opposite sides of the welding groove;

5. The method for realizing the ultralow interbay welding temperature according to claim 1, wherein the method comprises the following steps: for non-revolving body weldment, the plasticine is adopted to manufacture the plasticine dyke.

6. The method for realizing ultralow interbay welding temperature according to claim 5, wherein the method comprises the following steps: the two plasticines are respectively positioned at two opposite sides of the welding line; each plasticine is made into a hollow rotary type plasticine dike, one end of the plasticine dike is provided with a water inlet pipe, the other end of the plasticine dike is provided with a water outlet pipe, and cooling water is filled in a cofferdam formed by the plasticine dike.

7. The method for realizing ultralow interbay welding temperature according to claim 5, wherein the method comprises the following steps: for the non-revolving body weldment, the dike is made of a water-impermeable material.