CN114043108B - Plasma and TIG welding method for ultrahigh-strength steel cylindrical part - Google Patents
Plasma and TIG welding method for ultrahigh-strength steel cylindrical part Download PDFInfo
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- CN114043108B CN114043108B CN202111496822.XA CN202111496822A CN114043108B CN 114043108 B CN114043108 B CN 114043108B CN 202111496822 A CN202111496822 A CN 202111496822A CN 114043108 B CN114043108 B CN 114043108B
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- 238000003466 welding Methods 0.000 title claims abstract description 164
- 238000000034 method Methods 0.000 title claims abstract description 25
- 229910000797 Ultra-high-strength steel Inorganic materials 0.000 title claims abstract description 21
- 230000009471 action Effects 0.000 claims abstract description 8
- 239000000463 material Substances 0.000 claims description 6
- 230000002238 attenuated effect Effects 0.000 claims description 3
- 230000002093 peripheral effect Effects 0.000 claims description 3
- 238000010791 quenching Methods 0.000 claims description 3
- 230000000171 quenching effect Effects 0.000 claims description 3
- 230000035515 penetration Effects 0.000 abstract description 12
- 230000008569 process Effects 0.000 abstract description 7
- 230000006978 adaptation Effects 0.000 abstract description 2
- 238000013461 design Methods 0.000 abstract description 2
- 229910000831 Steel Inorganic materials 0.000 description 2
- 239000007789 gas Substances 0.000 description 2
- 238000005304 joining Methods 0.000 description 2
- 239000010959 steel Substances 0.000 description 2
- 238000012360 testing method Methods 0.000 description 2
- 230000004075 alteration Effects 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 238000005336 cracking Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000011261 inert gas Substances 0.000 description 1
- 238000003754 machining Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000003908 quality control method Methods 0.000 description 1
- 238000006467 substitution reaction Methods 0.000 description 1
- 230000007704 transition Effects 0.000 description 1
- WFKWXMTUELFFGS-UHFFFAOYSA-N tungsten Chemical compound [W] WFKWXMTUELFFGS-UHFFFAOYSA-N 0.000 description 1
- 229910052721 tungsten Inorganic materials 0.000 description 1
- 239000010937 tungsten Substances 0.000 description 1
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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
- B23K28/00—Welding or cutting not covered by any of the preceding groups, e.g. electrolytic welding
- B23K28/02—Combined welding or cutting procedures or apparatus
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Abstract
The invention relates to a plasma and TIG welding method for an ultrahigh-strength steel cylindrical part, belonging to the field of welding of ultrahigh-strength steel; firstly, the assembly clearance L is determined 1 And assembly misalignment L 2 (ii) a Then, welding groove design: through the alternative combination form of the single-side V-shaped groove and the non-groove part on the back of the welding seam, the single-side groove on the back ensures the strength and the thickness of the positioning welding seam, the non-groove part on the back ensures the effective action range of a positioning area, and the thickness and the total length of the positioning welding spot are reduced; finally, through accurate welding track control and welding parameter adjustment, the rapid adaptation of the welding parameters of the circular seam closed-loop joint area is realized, and the quality problems of incomplete penetration or welding leakage and the like of the circular seam closed-loop joint area are avoided. The invention can solve the quality problems of incomplete penetration or welding leakage and the like caused by factors such as inconsistent assembly clearance and staggered edge amount, uneven thickness of a positioning welding spot, inconsistent wall thickness of a circular seam closed loop cross connection area and the like in the plasma and TIG welding process of the ultrahigh-strength steel cylindrical part.
Description
Technical Field
The invention belongs to the field of ultrahigh strength steel welding, and particularly relates to a plasma and TIG welding method for an ultrahigh strength steel cylindrical part.
Background
Plasma and TIG are a hybrid welding technology, namely, the plasma is adopted to carry out backing layer welding, and Tungsten Inert Gas (TIG) welding is adopted to carry out filling cover layer welding, so that one-time welding penetration is increased, the welding layer number of products is reduced, and the welding efficiency is improved by virtue of the characteristics of high plasma energy density and large welding penetration. However, plasma welding has a high requirement on the pre-welding state of the weld, and if the consistency of the pre-welding state is poor, quality problems such as incomplete penetration or welding leakage caused by mismatching of parameters can occur, so that the product quality is affected. For the ultra-high strength steel cylindrical part, the pre-welding state of the welding seam is mainly influenced by the following three aspects:
1) The gap and the misalignment caused by the assembly quality are inconsistent. When a product is welded, the misalignment amount and the gap of circular seam assembly need to be adjusted, but due to the influence of part deformation and machining precision, the product cannot be completely guaranteed to have no misalignment amount and gap, but the quality of assembly needs to be controlled within a certain range, so that quality problems such as incomplete penetration or welding leakage cannot be ensured to be relatively difficult to determine.
2) The difference in wall thickness caused by the tack welds. Before welding a product, the assembly quality needs to be fixed in a positioning welding mode, the assembly quality meets the requirements in the welding process, but the existence of the positioning welding points increases the wall thickness of the local part of the product, so that the problems of incomplete penetration or welding leakage are caused. If reduce positioning welding point's thickness, again because the product is super high strength steel cylinder, its intensity is high, and the rigidity is great, need adopt the mode of powerful assembly to guarantee the assembly quality in assembling process, the product has great stress, and positioning welding point thickness reduces the back, will lead to positioning welding point intensity not enough, and the welding point fracture can't guarantee the assembly quality.
3) The wall thickness difference that exists when the circumferential seam forms a closed loop. In the process of carrying out girth welding, when the welding seam forms the closed loop, can pass through by the joining region of not welding the position transition to the welding position, because after the welding position formed the welding seam, the wall thickness had changed, and joining region has certain thick wall difference, quality problems such as the non-penetration that the parameter mismatching leads to or weld hourglass easily appear.
Disclosure of Invention
The technical problem to be solved is as follows:
in order to avoid the defects of the prior art, the invention provides a plasma and TIG welding method for an ultrahigh-strength steel cylindrical part, which adopts a unique process scheme, reduces the influence caused by assembly quality, positioning welding spots and circular seam closed loops, realizes the quality control of the ultrahigh-strength steel cylindrical part by plasma and TIG welding, and solves the problem of difficult control of the welding quality of the steel cylinder with the diameter of more than or equal to 500mm in the prior art.
The technical scheme of the invention is as follows: a plasma and TIG welding method for an ultra-high strength steel cylindrical part is characterized by comprising the following specific steps:
the method comprises the following steps: determination of the fitting clearance L 1 And assembly misalignment L 2 The formula is as follows:
L 1 +0.5L 2 ≤0.1δ
L 1 ≤0.5
wherein L is 1 Fitting clearance for product butt welds, L 2 Assembling the misalignment amount for the butt weld of the product, wherein delta is the wall thickness of the product, and the units are mm;
step two: designing a welding groove:
when the wall thickness delta of the product is less than 6mm, the front side of the welding seam adopts a groove-free form, and the back side of the welding seam is provided with a plurality of sections of single-side V-shaped grooves at intervals along the circumferential direction;
when the wall thickness delta of the product is more than or equal to 6mm, V-shaped grooves with the depth of 2mm are formed in the front of the welding line, and a plurality of sections of single-side V-shaped grooves are formed in the back of the welding line at intervals along the circumferential direction;
step three: starting welding;
firstly, positioning and welding a plurality of sections of single-side V-shaped grooves on the back of a welding seam of a product by TIG welding, and filling and leveling all the single-side V-shaped grooves to be flush with the peripheral surface of a base material; then, performing interval positioning welding on the position without the bevel part on the back of the welding line of the product by adopting TIG welding; further, plasma welding is adopted to weld from the front of the product along the circumferential direction of a welding line, welding is started from an arc starting point A, when the action part of a welding gun reaches the point A again, welding parameters are kept unchanged, and welding is continued, when the action part of the welding gun reaches a point B which is 5mm away from the point A, a gradual attenuation arc quenching mode is started, parameters of plasma gas are manually adjusted, and the parameters are attenuated to zero within 1 s; and finally, filling and capping welding the unfilled part on the front side of the welding line by adopting TIG welding to ensure that the residual height of the welding line is higher than that of the base material.
The invention further adopts the technical scheme that: the multi-section unilateral V-shaped grooves are uniformly distributed along the circumferential direction of the back of the welding line, the total length of the unilateral V-shaped grooves accounts for 8% -10% of the total length of the welding line, and the unilateral V-shaped grooves are equally divided into 8 sections.
The further technical scheme of the invention is as follows: the total length of the non-groove part is 90% -92% of the total length of the welding line, the total length is divided into 8 sections, and the non-groove part and the single-side V-shaped groove area are alternately distributed.
The invention further adopts the technical scheme that: the depth of the unilateral V-shaped groove is 2mm.
The invention further adopts the technical scheme that: the arc length of the unilateral V-shaped groove is 60mm.
The further technical scheme of the invention is as follows: the groove-free part between two adjacent sections of single-side V-shaped grooves is welded in the following mode: and performing positioning welding seam welding with the height not more than 0.5mm and the length 10mm every 100 mm.
Advantageous effects
The invention has the beneficial effects that: the invention can solve the quality problems of incomplete penetration or welding leakage and the like caused by factors such as inconsistent assembly clearance and staggered edge amount, uneven thickness of positioning welding spots, inconsistent wall thickness of a circular seam closed loop cross-connecting area and the like in the process of plasma and TIG welding of the ultrahigh-strength steel cylindrical part.
The principle for solving the quality problem of plasma and TIG welding of the ultrahigh-strength steel cylindrical part is as follows: firstly, through test verification, the control requirements of the assembly misalignment amount and the assembly clearance are determined, so that the plasma welding method can meet the application range of plasma welding and can adapt to the wall thickness change to a certain degree; secondly, by adopting a combined groove form, the strength and the thickness of the positioning welding line are ensured by adopting a groove on the single side of the back surface, the effective action range of a positioning area is ensured by adopting a groove-free back surface, and the thickness and the total length of the positioning welding point are reduced; finally, through accurate welding track control and welding parameter adjustment, the rapid adaptation of the welding parameters of the circular seam closed-loop joint area is realized, and the quality problems of incomplete penetration or welding leakage and the like of the circular seam closed-loop joint area are avoided.
The arc length of the single-side V-shaped groove and the arc length proportion of the groove-free part are limited, so that the product can be guaranteed to provide enough constraint strength in the assembling process, the positioning part is guaranteed not to crack, the minimum of the positioning welding workload can be realized, the working strength of operators is reduced, and the positioning firmness and the coordination of the workload are realized.
Tests prove that after the plasma and TIG welding method provided by the invention is adopted to carry out girth welding on an ultrahigh-strength steel cylindrical product, the quality problems of incomplete penetration or welding leakage and the like caused by mismatching of parameters do not occur, and the welding quality is effectively ensured.
Drawings
Fig. 1 is a schematic view of the assembly form of the product.
FIG. 2 is a schematic view of a first welding groove.
FIG. 3 is a schematic view of a second welding groove.
FIG. 4 is a schematic view of the welding trace of the present invention.
Description of the reference numerals: 1. a first workpiece, 2, a second workpiece.
Detailed Description
The embodiments described below with reference to the accompanying drawings are illustrative and intended to explain the present invention and should not be construed as limiting the present invention.
The invention relates to a plasma and TIG welding method of an ultrahigh-strength steel cylindrical part, which comprises the following specific steps of:
the method comprises the following steps: referring to fig. 1, a fitting clearance L is determined 1 And assembly misalignment L 2 The formula is as follows:
L 1 +0.5L 2 ≤0.1δ
L 1 ≤0.5
wherein L is 1 Fitting gaps for butt welds of products, L 2 Assembling the misalignment amount for the butt weld of the product, wherein delta is the wall thickness of the product, and the units are mm;
step two: the welding groove design is shown in fig. 2 and 3:
when the wall thickness delta of the product is less than 6mm, the front side of the welding seam adopts a groove-free form, and a plurality of sections of unilateral V-shaped grooves with the depth of 2mm are arranged at intervals along the circumferential direction on the back side of the welding seam;
when the wall thickness delta of the product is more than or equal to 6mm, V-shaped grooves with the depth of 2mm are formed in the front surface of the welding line, and a plurality of sections of single-side V-shaped grooves with the depth of 2mm are arranged on the back surface of the welding line at intervals along the circumferential direction;
a single-side V-shaped groove with 8 sections of arc lengths of 60mm is uniformly distributed on the back of the whole welding line of the product along the circumferential direction, such as the groove shown in FIG. 3; the rest of the parts are in the form of bevels as shown in figure 2.
Step three: starting welding;
firstly, performing positioning welding on 8 sections of single-side V-shaped grooves on the back of a welding seam of a product by adopting TIG welding, and filling all the single-side V-shaped grooves to be flush with the peripheral surface of a base material;
then, performing interval positioning welding on the position without the bevel part on the back of the welding line of the product by adopting TIG welding; welding positioning welding seams with the height not more than 0.5mm and the length of 10mm at intervals of 100 mm; by adopting the form of a back single-side groove, the effective penetration of the positioning welding spot is increased, the stress bearing capacity of the positioning welding spot is improved, and the positioning welding spot is prevented from cracking due to insufficient strength;
further, plasma welding is adopted to weld from the front of the product along the circumferential direction of a welding line, welding is started from an arc starting point A, when the action part of a welding gun reaches the point A again, welding parameters are kept unchanged, and welding is continued, when the action part of the welding gun reaches a point B which is 5mm away from the point A, a gradual attenuation arc quenching mode is started, parameters of plasma gas are manually adjusted, and the parameters are attenuated to zero within 1 s;
and finally, filling and capping welding are carried out on the unfilled part on the front side of the welding line by adopting TIG welding, so that the surplus height of the welding line is higher than that of the base material.
Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention, and that variations, modifications, substitutions and alterations can be made in the above embodiments by those of ordinary skill in the art without departing from the principle and spirit of the present invention.
Claims (6)
1. A plasma and TIG welding method for an ultra-high strength steel cylindrical part is characterized by comprising the following specific steps:
the method comprises the following steps: determination of the fitting clearance L 1 And assembly misalignment L 2 The formula is as follows:
L 1 +0.5L 2 ≤0.1δ
L 1 ≤0.5
wherein L is 1 Fitting gaps for butt welds of products, L 2 Assembling misalignment amount for a butt weld of a product, wherein delta is the wall thickness of the product, and the above units are mm;
step two: designing a welding groove:
when the wall thickness delta of the product is less than 6mm, the front side of the welding seam adopts a groove-free form, and a plurality of sections of single-side V-shaped grooves are arranged on the back side of the welding seam at intervals along the circumferential direction;
when the wall thickness delta of the product is more than or equal to 6mm, V-shaped grooves with the depth of 2mm are formed in the front of the welding line, and a plurality of sections of single-side V-shaped grooves are formed in the back of the welding line at intervals along the circumferential direction;
step three: starting welding;
firstly, performing positioning welding on a plurality of sections of single-side V-shaped grooves on the back of a welding seam of a product by adopting TIG welding, and filling all the single-side V-shaped grooves to be flush with the peripheral surface of a base material; then, performing interval positioning welding on the position without the bevel part on the back of the welding line of the product by adopting TIG welding; further, plasma welding is adopted to weld from the front of the product along the circumferential direction of a welding line, welding is started from an arc starting point A, when the action part of a welding gun reaches the point A again, welding parameters are kept unchanged, and welding is continued, when the action part of the welding gun reaches a point B which is 5mm away from the point A, a gradual attenuation arc quenching mode is started, parameters of plasma gas are manually adjusted, and the parameters are attenuated to zero within 1 s; and finally, filling and capping welding are carried out on the unfilled part on the front side of the welding line by adopting TIG welding, so that the surplus height of the welding line is higher than that of the base material.
2. The plasma + TIG welding method of ultra-high strength steel cylindrical member according to claim 1, wherein: the multi-section unilateral V-shaped grooves are uniformly distributed along the circumferential direction of the back of the welding line, the total length of the unilateral V-shaped grooves accounts for 8% -10% of the total length of the welding line, and the unilateral V-shaped grooves are equally divided into 8 sections.
3. The plasma + TIG welding method of ultra-high strength steel cylindrical pieces according to claim 2, wherein: the total length of the non-groove part is 90% -92% of the total length of the welding line, the total length is divided into 8 sections, and the non-groove part and the single-side V-shaped groove area are alternately distributed.
4. The plasma + TIG welding method of ultra-high strength steel cylindrical pieces of claim 1, wherein: the depth of the unilateral V-shaped groove is 2mm.
5. The plasma + TIG welding method of ultra-high strength steel cylindrical pieces of claim 1, wherein: the arc length of the unilateral V-shaped groove is 60mm.
6. The plasma + TIG welding method of ultra-high strength steel cylindrical pieces of claim 1, wherein: the groove-free part between two adjacent sections of single-side V-shaped grooves is welded in the following mode: and performing positioning welding seam welding with the height not more than 0.5mm and the length 10mm every 100 mm.
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| JP6689238B2 (en) * | 2017-08-24 | 2020-04-28 | 株式会社Ｉｈｉ検査計測 | Temporary welding method and temporary welding apparatus |
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| CN104668747A (en) * | 2015-01-28 | 2015-06-03 | 大连齐车轨道交通装备有限责任公司 | Method for welding tanks of railway tank vehicles |
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