CN108788385B - Welding method of stainless steel composite plate with Q345R low alloy steel as base layer and 904L stainless steel as multiple layers - Google Patents
Welding method of stainless steel composite plate with Q345R low alloy steel as base layer and 904L stainless steel as multiple layers Download PDFInfo
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- CN108788385B CN108788385B CN201810690368.3A CN201810690368A CN108788385B CN 108788385 B CN108788385 B CN 108788385B CN 201810690368 A CN201810690368 A CN 201810690368A CN 108788385 B CN108788385 B CN 108788385B
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- B—PERFORMING OPERATIONS; TRANSPORTING
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- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
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- B—PERFORMING OPERATIONS; TRANSPORTING
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- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K9/00—Arc welding or cutting
- B23K9/16—Arc welding or cutting making use of shielding gas
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
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- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
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Abstract
The invention relates to a stainless steel composite plate welding method taking Q345R low alloy steel as a base layer and 904L stainless steel as a composite layer, which comprises the following steps: processing a groove; the welding is completed in three stages, namely the welding of a base layer, specifically the welding of a stainless steel side base layer and the welding of a carbon steel side base layer, the welding of a multi-layer and multi-pass welding method is adopted, the welding of a transition layer at the joint of the base layer and the clad layer is carried out, finally the welding of the stainless steel clad layer is carried out, and the welding of the transition layer and the clad layer is carried out by adopting the multi-pass welding method. And (3) according to different welding parent metal materials, using corresponding welding materials, and completing the welding of the stainless steel composite plate by different welding methods and welding process parameters. The method is simple and convenient to operate, and can ensure the welding quality and improve the welding efficiency.
Description
Technical Field
The invention relates to a welding method of stainless steel composite plates, in particular to a welding method of a stainless steel composite plate with Q345R low alloy steel as a base layer and 904L stainless steel as a composite layer.
Background
The stainless steel composite plate is a composite steel plate formed by combining a carbon steel or low alloy steel base layer and a stainless steel composite layer, and the carbon steel and the stainless steel form firm metallurgical bonding by explosion cladding or hot rolling cladding and other methods. The stainless steel composite board not only has the corrosion resistance of stainless steel, but also has good mechanical strength and processability of carbon steel, and is a novel industrial product. The application of the product can save a large amount of stainless steel and has good economic value.
For welding the stainless steel composite plate, in order to ensure that the composite steel plate does not lose the original comprehensive performance, the carbon steel base layer and the stainless steel composite layer are respectively welded. Besides the welding of the base layer and the composite layer, the welding of the transition layer is also a main characteristic of the welding of the stainless steel composite plate. Transition welding seams are adopted between the multi-layer welding seams and the base layer welding seams. When the transition layer is welded, the local melting of the base layer structural steel dilutes the alloy components of the stainless steel welding seam. Martensite structures are easily formed in welding seams, the plasticity, the toughness and the corrosion resistance of a welding joint are reduced, cracks are easily generated at the joint, the welding of the joint is not firm, and the quality of the joint is influenced. Therefore, the welding of the transition layer is the key of the welding of the stainless steel composite plate.
Disclosure of Invention
The technical problem to be solved by the invention is to provide a method for welding a stainless steel composite plate by using Q345R low alloy steel as a base layer and 904L stainless steel as a composite layer, so that a large amount of martensite structures and welding cold cracks can be avoided, and the welding quality of a welding seam can meet the requirement.
The technical scheme adopted for solving the technical problems is as follows:
a stainless steel clad plate welding method taking Q345R low alloy steel as a base layer and 904L stainless steel as a clad layer comprises the steps of processing a groove, wherein the groove is a K-shaped groove; further comprising the steps of:
(1) welding a base layer, wherein a welding base material is Q345R + Q345R, a welding material is a THY-51B flux-cored wire, welding is carried out by adopting CO2 gas shielded welding, and the preheating temperature before welding is 80-150 ℃; welding a base layer welding seam on the stainless steel side, wherein after welding is finished, the surface of the welding seam is 6-7 mm lower than that of the stainless steel; back carbon rod back chipping of the welding seam, polishing to be bright, and carrying out MT detection on the polished gouging surface; then welding a base layer welding seam at the side of the carbon steel, wherein the rest height of the welding seam is 2 +/-1 mm; welding a base layer by adopting a multilayer multi-pass welding method, and controlling the temperature between passes to be 80-150 ℃;
(2) welding a transition layer, wherein a welding base material is 904L + Q345R, a welding material is an E385-16 welding rod, manual arc welding is adopted, the drying temperature of the welding rod is 350-400 ℃, and a welding line is welded to a position 3-4 mm below the surface of the stainless steel clad steel plate; the transition layer is welded by adopting a single-layer multi-pass welding method, and the temperature between welding passes is less than 100 ℃;
(3) and (3) multi-layer welding, wherein a welding base material is 904L +904L, a welding material is an E385-16 welding rod, the drying temperature of the welding rod is 350-400 ℃, a multi-pass welding method is adopted to complete filling and cover surface welding of a stainless steel welding layer, the residual height of a welding line of the stainless steel multi-layer is 0-1.5 mm, and the temperature between welding lines is less than 100 ℃.
Compared with the prior art, the invention adopting the technical scheme has the beneficial effects that:
the welding method comprises the steps of welding in a layered mode, wherein adaptive welding materials and welding process parameters are adopted for different welding layers, and a multi-layer and multi-pass welding method is adopted for a base layer welding seam, so that the cooling of the welding layer can be slowed down, and cracks are avoided; the single-layer welding is adopted for the transition layer, so that the cracks of the welding line caused by overheating of the stainless steel composite layer can be prevented. The invention not only improves the quality of the welding joint of the composite board, but also greatly improves the welding success rate, thereby improving the welding efficiency.
Further, the preferred scheme of the invention is as follows:
the angle of the K-shaped groove is 40-45 degrees at the upper side, 10-15 degrees at the lower side, 0-3 mm at the truncated edge of the groove and 0-3 mm at the root gap.
In the step (1), the THY-51B flux-cored wire comprises the following chemical components in percentage by mass: c: 0.05; mn: 1.11; si: 0.35; s: 0.008; p: 0.013; cr: 0.02; ni: 0.01.
the welding process parameters of the step (1) are as follows: the current is 180-240A, the voltage is 28-35V, the welding speed is 10-22 cm/min, and the gas flow is 18-22L/min.
In the step (1), after welding of a base layer welding seam on the stainless steel side is completed, back of the welding seam is subjected to carbon rod back chipping and polished to be bright, and MT detection is carried out on the polished gouging surface; and after welding the base layer weld at the carbon steel side, polishing the surface of the weld by using a grinding wheel, removing burrs, and performing UT detection after 24 hours.
The welding rod E385-16 in the step (2) and the step (3) comprises the following chemical components in percentage by mass: c: 0.028; mn: 1.67; si: 0.58; s: 0.007; p: 0.015; cr: 20.52; ni: 25.23; mo: 4.98 of; cu: 1.69.
the welding process parameters of the step (2) and the step (3) are as follows: the current is 120-170A, the voltage is 25-32V, and the welding speed is 8-22 cm/min.
And (3) in the step (2), performing PT detection 24 hours after the welding of the transition layer is finished.
And (3) performing UT and PT detection 24 hours after the multilayer welding is finished.
Drawings
FIG. 1 is a schematic view of weld groove preparation;
FIG. 2 is a schematic view of the welding of a base layer on the stainless steel clad layer side;
FIG. 3 is a schematic illustration of the welding of a base layer on the carbon steel side;
FIG. 4 is a schematic view of a transition layer weld;
FIG. 5 is a schematic illustration of stainless steel clad welding;
in the figure: i, Q345R low alloy steel base layer; II, 904L stainless steel cladding; 1. stainless steel side base layer welding lines; 2. a carbon steel side group layer weld; 3. a transition layer weld; 4. stainless steel multilayer weld.
Detailed Description
The present invention will be described in detail below with reference to the accompanying drawings and examples.
The welding method described in this embodiment is a stainless steel composite plate transverse welding (H) welding method using Q345R low alloy steel as a base layer and 904L stainless steel as a clad layer, and is performed according to the following steps:
(1) processing a groove: referring to fig. 1, the welding end face of the stainless steel composite plate is processed into a K-shaped groove, the angle upper side of the K-shaped groove is 40-45 degrees, the angle lower side of the K-shaped groove is 10-15 degrees, the truncated edge of the groove is 0-3 mm, and the root gap is 0-3 mm. .
(2) Welding a base layer: referring to fig. 2 and 3, the base layer welding is performed in two parts, namely, a stainless steel side base layer welding seam 1 and a carbon steel side group layer welding seam 2, and the welding is performed in the sequence of welding the stainless steel side base layer welding seam 1 and then welding the carbon steel side group layer welding seam 2. The welding parent metal is: Q345R + Q345R, adopting CO2 gas shielded welding for welding, selecting THY-51B as a welding wire, wherein the diameter is 1.2mm, the polarity of a welding power supply is DCEP, the current is adjusted to 180-240A, the voltage is adjusted to 28-35V, the welding speed is 10-22 cm/min, and the gas flow is 18-22L/min. And (3) adjusting all welding process parameters in place by adopting a multilayer multi-pass welding method, starting to weld the stainless steel side base layer weld joint 1, and controlling the temperature between passes to be 80-150 ℃. In order to ensure the welding quality of the transition layer, the surface of the welding seam is 6-7 mm lower than that of the stainless steel. And (4) back carbon arc gouging back gouging, polishing to be bright, and welding the welding seam 2 of the carbon steel side group layer after the MT detection is qualified.
The welding of the carbon steel side base layer welding seam 2 also adopts the welding method of the stainless steel side base layer welding seam 1, all the welding process parameters are the same as those of the stainless steel side base layer welding seam 1, the welding seam surplus height is 2 +/-1 mm, after the welding is finished, the surface of the welding seam needs to be polished smoothly by a grinding wheel, burrs are removed, and the UT detection is carried out after the welding is finished for 24 hours.
And after the welding of the base layer is finished, performing ultrasonic flaw detection after 24 hours, and welding the transition layer after the PT detection on the surface of the welding seam 1 of the stainless steel side base layer is qualified.
(3) Welding a transition layer: referring to fig. 4, the welding seam 3 of the transition layer is a key part of the whole welding process, an oxide layer on the surface is removed before welding, and the surface of the welding seam is polished to be bright. The welding parent metal is: 904L + Q345R, adopting manual arc welding, wherein the welding material is an E385-16 welding rod with the diameter of 4mm, the drying temperature of the welding rod is 350-400 ℃, the polarity of a welding power supply is DCEP, and the welding process parameters are as follows: the current is 120-170A, the voltage is 25-32V, and the welding speed is 8-22 cm/min. And welding the welding seam to the position 3-4 mm below the surface of the stainless steel clad steel plate. The welding method of single-layer multi-pass welding is adopted for welding, and the temperature between welding passes is less than 100 ℃. During welding, swinging is forbidden, welding straightness is controlled, and welding seams of transition layers on two sides of the groove are connected with the stainless steel clad layer of the base material and are in smooth transition. PT detection is carried out 24 hours after welding.
(4) Multilayer welding: referring to fig. 5, the multilayer weld seam 4 is welded, and the welding parent metal is: 904L +904L, the same as the transition layer welding seam 3, adopting manual arc welding, wherein the welding material is an E385-16 welding rod with the diameter of 4mm, the drying temperature of the welding rod is 350-400 ℃, and the polarity of a welding power supply is DCEP. Welding technological parameters are welded with the welding seam 3 of the transition layer, a multi-pass welding method is adopted to complete filling and cover surface welding of a stainless steel welding layer, the welding seam surplus height of the stainless steel compound layer is 0-1.5 mm, and the temperature between welding passes is less than 100 ℃. UT and PT detection is carried out 24 hours after welding, and the surface of the stainless steel clad weld joint qualified by surface inspection does not need to be polished.
The above description is only an example of the present invention, and not intended to limit the scope of the present invention, and all equivalent variations using the content of the present specification are included in the scope of the present invention.
Claims (1)
1. A stainless steel composite plate transverse welding method taking Q345R low alloy steel as a base layer and 904L stainless steel as a clad layer is characterized by comprising the following steps:
(1) processing a groove: processing the welding end face of the stainless steel composite plate into a K-shaped groove, wherein the upper side of the angle of the K-shaped groove is 40-45 degrees, the lower side of the angle of the K-shaped groove is 10-15 degrees, the truncated edge of the groove is 0-3 mm, and the root gap is 0-3 mm;
(2) welding a base layer: welding the base layer in two parts, namely welding a stainless steel side base layer welding seam and a carbon steel side base layer welding seam, and welding the stainless steel side base layer welding seam and the carbon steel side base layer welding seam in sequence; the welding parent metal is: Q345R + Q345R, adopting CO2 gas shielded welding for welding, selecting THY-51B as a welding wire, wherein the diameter is 1.2mm, the polarity of a welding power supply is DCEP, the current is adjusted to 180-240A, the voltage is adjusted to 28-35V, the welding speed is 10-22 cm/min, and the gas flow is 18-22L/min; adjusting welding technological parameters in place by adopting a multilayer multi-pass welding method, starting to weld stainless steel side base layer welding seams, and controlling the temperature between passes to be 80-150 ℃; in order to ensure the welding quality of the transition layer, the surface of a welding seam is 6-7 mm lower than that of stainless steel; back carbon arc gouging back, polishing and polishing, and welding the welding seam of the side carbon steel layer after the MT detection is qualified;
welding the welding seam of the carbon steel side base layer by adopting a welding method of the welding seam of the stainless steel side base layer, welding all technological parameters with the welding seam of the stainless steel side base layer, wherein the welding seam surplus height is 2 +/-1 mm, after the welding is finished, the surface of the welding seam needs to be polished smoothly by adopting a grinding wheel, burrs are removed, and UT detection is carried out after the welding is finished for 24 hours;
after the welding of the base layer is finished, performing ultrasonic flaw detection after 24 hours, and welding the transition layer after the PT detection on the surface of the welding seam of the stainless steel side base layer is qualified;
(3) welding a transition layer: the welding seam of the transition layer is a key part in the whole welding process, an oxide layer on the surface is removed before welding, and the surface of the welding seam is polished to be bright; the welding parent metal is: 904L + Q345R, adopting manual arc welding, wherein the welding material is an E385-16 welding rod with the diameter of 4mm, the drying temperature of the welding rod is 350-400 ℃, the polarity of a welding power supply is DCEP, and the welding process parameters are as follows: the current is 120-170A, the voltage is 25-32V, and the welding speed is 8-22 cm/min; welding a welding seam to a position 3-4 mm below the surface of the stainless steel clad steel plate; welding by adopting a single-layer multi-pass welding method, wherein the temperature between welding passes is less than 100 ℃; during welding, the swinging is forbidden, the welding straightness is controlled, and the welding seams of the transition layers on the two sides of the groove are connected with the stainless steel clad layer of the base material and are in smooth transition; performing PT detection 24 hours after welding;
(4) multilayer welding: welding a multilayer welding seam, wherein the welding base material is as follows: 904L +904L, the same as the transition layer welding seam, adopting manual arc welding, wherein the welding material is an E385-16 welding rod with the diameter of 4mm, the drying temperature of the welding rod is 350-400 ℃, and the polarity of a welding power supply is DCEP; welding technological parameters with the welding seam of the transition layer, and completing filling and cover surface welding of a stainless steel welding layer by adopting a multi-pass welding method, wherein the residual height of the welding seam of the stainless steel clad layer is 0-1.5 mm, and the temperature between welding passes is less than 100 ℃; UT and PT detection is carried out 24 hours after welding, and the surface of the stainless steel clad weld joint qualified by surface inspection does not need to be polished.
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| CN110026642A (en) * | 2019-04-10 | 2019-07-19 | 中广核研究院有限公司 | The butt welding method and double-sided composite plate interfacing part of double-sided composite plate |
| CN110026644B (en) * | 2019-04-10 | 2021-11-09 | 中广核研究院有限公司 | Angle welding method and angle connector for composite board and duplex stainless steel |
| CN110026648A (en) * | 2019-04-10 | 2019-07-19 | 中广核研究院有限公司 | The butt welding method and interfacing part of two phase stainless steel and composite plate |
| CN110026647A (en) * | 2019-04-10 | 2019-07-19 | 中广核研究院有限公司 | The butt welding method and interfacing part of single side composite plate |
| CN110026661A (en) * | 2019-04-10 | 2019-07-19 | 中广核研究院有限公司 | The butt welding method and interfacing part of double-sided composite plate and two phase stainless steel |
| CN115283800A (en) * | 2022-08-31 | 2022-11-04 | 中国铁建大桥工程局集团有限公司 | Welding method for double-metal high-strength composite bridge steel X-shaped joint |
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| CN205852093U (en) * | 2016-07-14 | 2017-01-04 | 中国核工业第五建设有限公司 | Nuclear power steel containment vessel circumferential weld automatic submerged arc horizontal welding groove |
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