CN109332923B - Automatic splicing method of ferritic stainless steel for explosive welding - Google Patents

Abstract

The automatic splicing method for ferritic stainless steel for explosive welding is characterized by that it adopts explosive welding to make once-through formation, its surface quality is good, plate shape control is good, and it has no wave deformation, and its welding seam performance can meet the technical evaluation requirements, and its bending and shearing properties can meet the standard requirements, so that it can reduce the repairing step in the production process, and can greatly save manpower and save production cost.

Description

Automatic splicing method of ferritic stainless steel for explosive welding

Technical Field

The invention relates to an explosive welding and splicing process method of materials, in particular to an automatic splicing method of ferrite stainless steel for explosive welding.

Background

The 0Cr13 type stainless steel mainly has several brands of 06Cr13, 06Cr13Al, etc., the stainless steel has excellent heat-resisting property, and is mainly used in large-scale equipment of coke tower, petrochemical industry such as coal oil, etc., the equipment generally has larger plate width, and the width of the domestic produced stainless steel is within 1500mm, so the stainless steel needs to be spliced and widened, because the stainless steel matrix contains martensite tissue, the weldability is poor, and the welding heat affected zone causes the reduction of the plastic toughness of the welding joint under the action of continuous welding heat circulation, after explosion welding, because the low plasticity of ferrite and the grain growth of the heat affected zone caused by the welding heat circulation and the accumulation of carbon and nitride on the grain boundary, under the condition that the welding joint of the 0Cr13 type stainless steel has large restraint degree, cracks are easily generated through the action of explosion.

At present, the splicing method of ferritic stainless steel 0Cr13 type stainless steel for explosive welding is carried out by using a large number of welding rod manual welding methods, which wastes time and labor and has poor working environment. The two welding methods have the defects of increased labor intensity and low production efficiency. See ZL200810141254.X a splicing method of 0Cr13 type ferritic stainless steel for explosive welding.

Disclosure of Invention

The invention aims to solve the problems that cracks and crack propagation are generated in a welding seam and a heat affected zone due to explosion impact after the ferritic stainless steel is subjected to explosion welding, and the production efficiency is extremely low due to the fact that subsequent steps such as welding seam planing and resurfacing welding are needed after the explosion welding.

In order to solve the technical problems, the invention adopts the technical scheme that:

an automatic splicing method of ferritic stainless steel for explosive welding comprises the following steps:

taking two stainless steel plates to be welded, and removing oil, water, rust or oxide layers and other dirt in the welding groove of the two stainless steel plates to be welded and the range of 50mm on two sides of the groove so as to avoid generating cracks, air holes and impurities and causing poor weld forming;

step two, placing the two stainless steel plates to be welded processed in the step one into a workbench, tightly pressing the two stainless steel plates to be welded by a piano key type pressing plate, and controlling the gap between jointed plates of the two stainless steel plates to be welded to be 0-1 mm;

step three, assembling and tack welding the stainless steel plates to be welded in the step two, controlling the welded junctions to be flush without staggered edges, wherein the tack welding length is 7-12 mm, and the spacing is 100-200 mm;

and fourthly, performing plasma arc welding on the stainless steel plate subjected to positioning welding in the third step, wherein the current of the plasma welding is 120-170A, the voltage is 20-26V, the welding speed is 200-400 mm/min, the welding wire adopts a dried ER321 welding wire, the ER321 welding wire is continuously fed in the welding process, the weld reinforcement is controlled within 0.5-1 mm, the energy of the plasma welding wire is more concentrated, the heat input is smaller, the range of a heat affected zone is small, the joint is more easily welded through, and the welding wire adopts the dried ER321 welding wire. Basically, all 0Cr13 welding uses an ER309L welding wire or a welding rod with the same component, and in the test process, the ER309L welding wire is also used, so that a large number of cracks still appear on a welding seam, the ER321 welding wire is selected to increase titanium elements in the components of the ER309L welding wire, and the titanium elements play a role of a grid in the welding seam through metallographic observation, so that various elements are connected into a net, the plasticity and the toughness of the welding seam area are increased, and the crack resistance of the welding seam area and a heat affected area is improved;

step five, after welding is finished, grinding the weld reinforcement, polishing the welding surface, and controlling the degree of finish to be 0.1-1.6;

taking the polished welding surface in the step five as an explosive bonding surface, and performing explosive welding with the base steel plate;

and step seven, after the explosive welding is finished, annealing the composite board at 800 ℃ and splicing.

The invention has the beneficial effects that: the invention has the advantages of one-step forming of welding, good surface quality, good plate shape control, no wave deformation, welding seam performance meeting technical evaluation requirements, and bending, shearing and other performances meeting standard requirements, reduces repairing steps in the production process, avoids the defects of hot cracks and the like in a welding seam area and a heat affected area after explosion welding, greatly saves labor and saves production cost.

Detailed Description

The specific implementation mode is as follows:

example one

Manufacturing a large-area 0Cr13 composite plate, namely placing two 06Cr13AL plates to be spliced on a splicing welding machine, wherein the sizes of the two plates are 3 x 1500 x 6800mm and 3 x 1300 x 6800mm, and removing dirt such as oil, water, rust, oxide layers and the like within the range of 50mm on two sides of a welded plate;

secondly, pressing the to-be-welded plate by using a piano key type pressing plate, wherein the gap is controlled to be 0-0.5 mm;

step three, welding openings are flush without staggered edges when assembling and positioning welding, the length of the positioning welding is 7-12 mm, and the distance is 100-200 mm;

setting the current of the plasma welding to be 120-170A, the voltage to be 20-26V, the welding speed to be 200-400 mm/min, and feeding an ER321 welding wire continuously in the welding process, wherein the diameter phi of the welding wire is 0.8mm, so that the welding seam is ensured to be filled, and the residual height is controlled to be within 0.5-1 mm;

step five, after welding is finished, grinding the weld reinforcement, polishing the surface to be clean, and controlling the degree of finish to be 1.6 to be used as an explosive bonding surface;

step six, selecting a Q345R plate with the size of 22 x 2750 x 6750 for the base layer to perform explosive welding;

and seventhly, after the explosive welding is finished, annealing the composite board at 800 ℃, splicing, carrying out nondestructive testing on the welding seam, and displaying that the joint performance is qualified and the mechanical performance result meets the standard requirement.

Example two

Manufacturing a large-area 0Cr13 composite plate, namely placing two 06Cr13 plates to be spliced, wherein the sizes of the two plates are 4 x 1400 x 5800mm and 4 x 1200 x 5800mm, on a splicing welding machine, and removing dirt such as oil, water, rust, an oxide layer and the like within the range of 50mm on two sides of a welded plate;

secondly, pressing the to-be-welded plate by using a piano key type pressing plate, wherein the gap is controlled to be 0-1 mm;

step three, welding openings are flush without staggered edges when assembling and positioning welding, the length of the positioning welding is 7-12 mm, and the distance is 100-200 mm;

setting the current of the plasma welding to be 120-170A, the voltage to be 20-26V, the welding speed to be 200-400 mm/min, and feeding an ER321 welding wire uninterruptedly in the welding process, wherein the diameter phi of the welding wire is 1.2mm, so that the welding seam is ensured to be filled, and the residual height is controlled to be within 0.5-1 mm;

step five, after welding is finished, grinding the weld reinforcement, polishing the surface to be clean, and controlling the degree of finish to be 0.1 to be used as an explosive bonding surface;

step six, selecting a Q345R steel plate with the size of 22 x 2550 x 5750 as the base layer to perform explosive welding;

and seventhly, after the explosive welding is finished, annealing the composite board at 800 ℃, splicing, carrying out nondestructive testing on the welding seam, and displaying that the joint performance is qualified and the mechanical performance result meets the standard requirement.

The technical solutions and embodiments of the present invention are not limited, and the same solutions or effects as those of the technical solutions and embodiments of the present invention are within the scope of the present invention.

Claims (2)

1. An automatic splicing method of 0Cr13 type ferritic stainless steel for explosive welding is characterized in that: the method comprises the following steps:

step one, taking two stainless steel plates to be welded, and removing welding grooves of the two stainless steel plates to be welded and dirt in the range of 50mm on two sides of the grooves;

step two, placing the two stainless steel plates to be welded processed in the step one into a workbench, tightly pressing the two stainless steel plates to be welded by a piano key type pressing plate, and controlling the gap between jointed plates of the two stainless steel plates to be welded to be 0-1 mm;

step three, assembling and tack welding the stainless steel plates to be welded in the step two, controlling the welded junctions to be flush without staggered edges, wherein the tack welding length is 7-12 mm, and the spacing is 100-200 mm;

performing plasma arc welding on the stainless steel plate subjected to positioning welding in the third step, wherein the current of the plasma welding is 120-170A, the voltage is 20-26V, the welding speed is 200-400 mm/min, the welding wire is an ER321 dried welding wire, the ER321 welding wire is continuously fed in the welding process, and the weld reinforcement is controlled within 0.5-1 mm;

step five, after welding is finished, grinding the weld reinforcement, polishing the welding surface, and controlling the degree of finish to be 0.1-1.6;

taking the polished welding surface in the step five as an explosive bonding surface, and performing explosive welding with the base steel plate;

and step seven, after the explosive welding is finished, annealing the composite board at 800 ℃ and splicing.

2. The automatic splicing method of 0Cr13 type ferritic stainless steel for explosion welding as set forth in claim 1, wherein: the dirt in the first step refers to any one of oil, water, rust or an oxide layer.