CN1012145B - Welding rods and technolgy for repair welding of white-iron roller - Google Patents
Welding rods and technolgy for repair welding of white-iron rollerInfo
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- CN1012145B CN1012145B CN 87101406 CN87101406A CN1012145B CN 1012145 B CN1012145 B CN 1012145B CN 87101406 CN87101406 CN 87101406 CN 87101406 A CN87101406 A CN 87101406A CN 1012145 B CN1012145 B CN 1012145B
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Abstract
The present invention relates to a welding rod and a technology for the repair welding of a white iron roller, which belongs to the technical field of the repair welding of cast iron. The present invention develops a BT-1 welding rod and a TB-2 welding rod for the repair welding of the white iron roller, wherein the BT-1 welding rod is used as a bottom layer of a welding seam, the BT-2 welding rod is used as a covering layer of the welding seam, and hard parts and soft parts of the welding seam are combined. In the welding technology, the isolated beam welding of deposited metal blocks is adopted, the contact surface between the deposited metal and a parent material is expanded, and measures which can farthest eliminate the thermal stress of welding are taken; thus, the welded white iron roller can meet operation requirements, and the welding seam has long service life. The present invention can also be used for the repair welding of large structural parts with poor weldability, such as various kinds of cast iron, high-carbon steel, etc.
Description
The invention belongs to the iron weld repair technical field, especially for the Repair Welding of white iron and white iron roll.
White iron has advantages such as hardness height, wearability be good, cheap, be widely used in making hot roll, cold roll, shaped steel foreplate and mining machinery etc., but because white iron is hard and crisp, it is big to reduce shrinkage factor with temperature, and scaling in use takes place easily, the local fatigue be full of cracks, casting flaw exposes etc., thereby causes white iron foundry goods scrappage very high.As the indefinite chill white cast iron roller, in rolling process, bear very big draught pressure, driving force distance and bending force distance, twisting resistance distance, and standing repeatedly from 50 ℃ to 700 ℃ temperature fluctuation, roller surface bears bigger contact pressure, wearing and tearing, fatigue etc., and under thermal stress and mechanical stress effect that alternation repeats, roller surface causes heat fatigue and mechanical fatigue easily, cause the part to peel off scaling, have a strong impact on the service life of roll.
In existing technology, welding stress when reducing built-up welding, prevent that crackle from producing, research was arranged on welding procedure both at home and abroad, substantially go up a kind of metal of the built-up welding that separates a determining deviation of first strip as the disclosed patent proposition of the clear 60-206568 of Japan is a kind of at stainless steel, and then import the method in intact its gap of built-up welding with a kind of welding rod with less heat energy.What China China Machine Press published in 1981 " should adopt methods such as rational welding sequence, discontinuous welding and hammering when pointing out welding cast iron in welder's handbook.
But because white iron is hard, crisp, plasticity is extremely low, so its solderability is very poor.What American Welding Society (AWS) published nineteen eighty-two " welds handbook and point out that white cast-iron can not weld under normal condition.Up to the present, for the soldering of white cast-iron, the Repair Welding of white iron hot roll particularly, at home and abroad not seeing as yet has the data report.
The objective of the invention is to study the welding rod special for special and the welding procedure thereof that are used for the white cast-iron welding, solve in the iron weld repair technical field, think for a long time white cast-iron be can not soldering this difficult problem, by Repair Welding, prolong the service life of white iron roll.
White iron roll central inner is a spheroidal graphite cast-iron, and the roll top layer is generally the thick white iron of 20～35mm, and microscopic structure is a small amount of pearlite that distributing on the matrix of continuous hard, crisp cementite.The white iron of roll is organized in below 350 ℃, the about 0.01J/cm of its ak
2, δ=0, H
S=60～70, cubical contraction is 4.5～5.4%, and linear shrinkage ratio is 1.6～2.3%.When the soldering roll, roll bears sweating heat adaptability to changes extreme difference, with existing electrode for cast iron and traditional handicraft soldering, unavoidably will produce the fissility crackle along the fusion area.
In order to make white cast-iron after the soldering can satisfy instructions for use and weld seam has long service life, the present invention develops BT-1 and two kinds of welding rods of BT-2, and white iron roll weld seam is welded by BT-1 welding rod and BT-2 welding rod.Whole welding line is made up of two parts, and the BT-1 welding rod is the high-ductility nickel one iron layer of weld seam bottom; The superficial layer that the BT-2 welding rod is that hardness is higher, wearability and white iron are complementary, deposited metal is close with white iron on linear expansion coefficient simultaneously, and good fusion character is arranged with white iron, and welding seam toughness is higher, stronger crack resistance, fatigue resistance and higher anti-temper resistance are arranged, improve the ability of fusion area antistripping and crackle.On welding procedure, enlarge the contact-making surface of weld seam and mother metal, and adopt the measure that can eliminate sweating heat stress to greatest extent, prevent that the fissility crackle from producing.
Welding procedure of the present invention adopts heterogeneous sea welding manual arc cold-welding technology, has broken through the conventional cold welding technique of grey cast-iron, and its welding procedure is:
1, welding white iron roll weld seam is with BT-1 welding rod prime coat, makes the overcoat of weld seam with the BT-2 welding rod, makes the combination of weld seam soft or hard.
2, the upright built-up welding of deposited metal elder generation piecemeal arc is expanded with heat and contract with cold it and is in than free state.The fusion area of weld seam and peripheral white iron forms in the final stage of soldering.
3, when the built-up welding bottom, adopt the soldering of 240A electric current with φ 4.0mm welding rod, impact the molten bath with electric arc, form big fusion penetration, mother metal is fully mixed with motlten metal, enlarge the contact-making surface of bottom and mother metal, fusion area, weld seam bottom forms a bigger tortuous fusion face.
4, when has just solidified in molten bath, welding back in time weight hit, along with overlay cladding increases, hammering is exerted oneself and hammer number can correspondingly reduce, and should guarantee to allow high-temperature metal fully extend, reduce sweating heat stress, unlikelyly again cause fusion area mechanicalness fatigue rupture because of impulsive force.
5, the edge of welding cut and bottom angle make weld seam upper and lower part amount of contraction identical by 90 ° of finishings, to reduce roller surface fusion zone crack tendency.
6, in welding process, be the basic operation gimmick to disperse the weldering of great-jump-forward point-like.
Adopt this process for welding repair, have tangible reduction sweating heat stress, prevent the effect that the fissility crackle takes place.
The BT-1 welding rod that is used for soldering white iron roll scaling bottom, be added with the graphite of capacity and an amount of nodulizer in the coating, deposited metal is organized as high-nickel austenite and globular graphite, with white iron good fusion character is arranged, plasticity is higher, ductility is preferably arranged during hammering, and higher crack resistance is arranged.
The core wire of BT-1 welding rod is the ferronickel core, and its coating proportioning (% by weight) is respectively:
Marble 15～19%
Fluorite 20～24%
Brium carbonate 26～31%
Graphite 5.1～6.1%
Rare earth magnesium 8.1～9.0%
Calcium-silicon 3.8～4.4%
Aluminium powder 2.5～3.2%
Solid sodium silicate 3.5～4.2%
With the glassy bond of K-Na mixing water
Be added with more graphite in the BT-1 electrode coating, make and separate out a large amount of globular graphites in the weld seam crystallization process, impel weld seam to expand and the reduction weld shrinkage; Add an amount of barium, calcium and rare earth magnesium and make nodulizer, graphite is had stronger spheroidization ability, thereby improve the crack resistance of weld seam.
The BT-2 welding rod is used for the overcoat of soldering white iron roll scaling, deposited metal structure be martensite+bainite+retained austenite.The deposited metal alloy system can satisfy roller surface to wearability, the stable requirement of anti-tempering, and between 40～600 ℃, the linear expansion coefficient of its linear expansion coefficient and white iron is very approaching under same temperature, the temperature fluctuation in the time of can adapting to steel rolling.
The core wire of BT-2 welding rod is H08A, and its coating proportioning (% by weight) is respectively:
Marble 26～32%
Fluorite 9.5～10.3%
Titanium dioxide 9.2～11.2%
Rutile 6.0～7.0%
Mid-carbon fe-mn 2.9～3.6%
Ferrotianium 10.0～13.0%
Nickel powder 8.0～8.8%
Graphite 1.0～1.5%
Ferrotungsten 1.4～2.1%
Vanadium iron 1.8～2.5%
Molybdenum-iron 6.0～7.0%
High carbon ferro-chrome 4.1～5.6%
Solid sodium silicate 2.8～3.6%
Sodium-potassium eutectic alterant 3.5～5.5%
Bond with the K-Na soluble glass of high modulus.
The W-Fe that adds in the BT-2 electrode coating composition, graphite, high C ferrochrome, V-Fe, Mo-Fe makes deposited metal form the antifriction alloy system of C-W-Cr-Mo-V, and wherein C and W, Cr, V can form the carbide of multiple high rigidity, improve the wearability of weld seam.Add nickel, make to keep the small portion of residual austenite in the seam organization.Add the sodium-potassium eutectic alterant, it is spherical to make the fusion area net carbide become group, improves the ability of fusion area antistripping, crackle.
The chemical analysis of BT-2 welding rod deposited metal is:
C0.4～0.46%
Si0.16～0.22%
Mn1.0～1.40%
Cr1.50～1.70%
Mo1.8～2.20%
Ni4.0～4.50%
W0.65～0.75%
V0.30～0.37%
The impact flexibility α k=20～30J/cm of BT-2 welding rod deposited metal
2, hardness HRC=43～48.The hardness of deposited metal is lower than mother metal slightly, but wearability and white cast-iron are suitable, has both guaranteed the wearability of weld seam, has improved the crack resistance of weld seam again.
The invention solves the key problem in technology that the white iron roll is difficult to soldering for a long time, prolonged the service life of white iron roll, and can be used for the Repair Welding of the spoken parts in traditional operas ironware in metallurgy, the mining machinery, also can be used for the Repair Welding of the relatively poor large-sized structural parts of solderabilities such as various cast irons, high-carbon steel, have obvious social and economic benefit.The present invention is with low cost, and technology is simple, and is easy to operate, is easy to promote the use of.
Embodiment:
Soldering to white iron roll scaling defective.
1, the finishing at scaling position before the soldering.
Fig. 1 is the cutaway view before the finishing of white iron roll scaling position, and Fig. 2 is the cutaway view after the finishing of white iron roll scaling position.(1) is the roll top layer.Scaling (2) and abscission layer (3) with grinding wheel, flat chisel, hand hammer breaker roll are thoroughly cleared up.Groove (4) edge and bottom angle are by 90 ° of finishings.
2, the built-up welding of groove bottom
Fig. 3 is the vertical view of groove, and Fig. 4 is the cutaway view of groove.In the good groove bottom of cleaning, mark solder joint (5) earlier, be about 30mm between the solder joint and with marginating compartment, adopt the BT-1 welding rod on the solder joint that marks, to carry out the weldering of great-jump-forward point-like.The core wire of BT-1 welding rod is the ferronickel core, and the electrode coating composition is: marble 19%, and fluorite 24%, brium carbonate 31%, graphite 6%, rare earth magnesium 8.5%, calcium-silicon 4.3%, aluminium powder 3.2%, solid sodium silicate 4% is with the glassy bond of K-Na mixing water.
Core diameter Φ 4.0mm, L=400mm, electric current 240A, 70 ℃ of interlayer temperatures are constantly impacted the molten bath with electric arc when welding, form big fusion penetration (6), after the blow-out, when just having solidified in the molten bath in time weight hit, be not easy to the marginal point flat chisel hammering of hammering, the solder joint volume Φ 30mm of postwelding, high 5mm.
3, the upright built-up welding of the above piecemeal arc of the second layer
Fig. 5 is the upright built-up welding cutaway view of piecemeal arc.Fig. 6 is the upright built-up welding vertical view of piecemeal arc.After having welded bottom, the overall stack welding zone is divided into some of 40 * 40mm areas, leave gap (10), (11) between its piecemeal (7), the about 6～8mm of relief width welds at the enterprising windrow of the piece of dividing with the BT-1 welding rod then.Welding current 180A, 70 ℃ of interlayer temperatures.When with the built-up welding of BT-1 welding rod to from rolling face 10mm the time, use the BT-2 welding rod instead and be soldered to and stop built-up welding when being higher than rolling face 2～3mm.The core wire of BT-2 welding rod is H08A, and the electrode coating composition is: marble 28%, fluorite 10%, titanium dioxide 10%, rutile 6%, mid-carbon fe-mn 3.0%, ferrotianium 11%, nickel powder 8.0%, graphite 1.5%, ferrotungsten 1.5%, vanadium iron 2%, high carbon ferro-chrome 5%, molybdenum-iron 6%, solid sodium silicate 3.5%, sodium-potassium eutectic alterant 4.5%.Bond with the K-Na soluble glass of high modulus.
Still disperse weldering for point-like during welding, each postwelding should carry out hammering.Overlay cladding is high more, and hammering is exerted oneself and number of times can correspondingly reduce.The bottom of the upright built-up welding of piecemeal arc is a BT-1 welding rod layer (8), and top is BT-2 welding rod layer (9).
4, the soldering in the upright gap of piecemeal arc
Fig. 7 is a deposited metal and the vertical view in white iron gap all around, and Fig. 8 is the cutaway view of Fig. 7.Fig. 9 is the cutaway view of weld seam.The gap soldering is carried out in two steps.
(1) soldering of deposited metal internal clearance.Deposited metal internal clearance (10) BT-1 welding rod prime coat, the BT-2 welding rod is made overcoat.Welding current 180A, 70 ℃ of interlayer temperatures.Still adopt to jump disperse weldering, hammering immediately after the blow-out is welded another section after reaching interlayer temperature again.Use the BT-2 welding rod instead after being soldered to respective heights with the BT-1 welding rod, flat with the whole welding line weldering.
(2) soldering in deposited metal and peripheral white iron gap.Deposited metal and peripheral white iron gap (11) are divided into 35～40mm plurality of sections, all carry out in proper order when welding every layer by A → B among Fig. 7 → C → D → E → F → G.Use the BT-1 welding rod, electric current 240A, 70 ℃ of interlayer temperatures during the welding bottom.The welding second layer is used the 180A electric current instead, when gap (11) finish layer (12) soldering with the BT-1 welding rod, use the BT-2 welding rod instead and be soldered to when being lower than roller surface 2～3mm and stop, layer (13) has welded top layer (14) with the BT-2 welding rod again, its electric current 180A, 50 ℃ of interlayer temperatures are still pressed A → B among Fig. 7 → C during welding ... order is carried out, and adopts the point-like weldering to divide full one section of three welderings, as being undertaken by (1) among Fig. 7 → (2) → (3), solder joint should exceed roller surface 2～3mm.After the weld seam (15) at whole scaling position has welded, with after the face of weld corase grind, arrive grinding machine again and process with emery wheel.
Claims (5)
1, a kind of method of utilizing rational welding sequence, discontinuous welding and hammering etc. to eliminate the cast iron welding stress is characterized in that this technology soft welding rod prime coat of BT-1, makes overcoat with BT-2 hard welding rod, the combination of weld seam soft or hard.The isolated built-up welding of deposited metal elder generation piecemeal.When the welding bottom, the lonely molten bath of impacting of electricity consumption forms big fusion penetration, enlarges the contact-making surface of bottom and mother metal, and fusion area, weld seam bottom forms a bigger tortuous fusion face.Between the isolated deposited metal, and with peripheral white iron between leave the gap, the fusion area of weld seam and peripheral white iron is in the formation of the final stage of soldering, in time weight hits when welding pool just solidifies, along with overlay cladding increases, hammering is exerted oneself and hammer number can correspondingly reduce.In whole welding process, be the basic operation gimmick to disperse the weldering of great-jump-forward point-like.
2, welding procedure according to claim 1, the core wire that it is characterized in that described BT-1 welding rod is the ferronickel core, coating proportioning (% by weight) is:
Marble 15～19%
Fluorite 20～24%
Brium carbonate 26～31%
Graphite 5.1～6.0%
Rare earth magnesium 8.1～9.0%
Calcium-silicon 3.8～4.4%
Aluminium powder 2.5～3.2%
Solid sodium silicate 3.5～4.2%
With the glassy bond of K-N α mixing water.
3, welding procedure according to claim 1, the core wire that it is characterized in that described BT-2 welding rod is HO8A, coating proportioning (% by weight) is:
Marble 26～32%
Fluorite 9.5～10.3%
Titanium dioxide 9.2～11.2%
Rutile 6.0～7.0%
Mid-carbon fe-mn 2.9～3.6%
Ferrotianium 10.0～13.0%
Nickel powder 8.0～8.8%
Graphite 1.0～1.5%
Ferrotungsten 1.4～2.1%
Vanadium iron 1.8～2.5%
Molybdenum-iron 6.0～7.0%
High carbon ferro-chrome 4.1～5.6%
Solid sodium silicate 2.8～3.6%
Sodium-potassium eutectic alterant 3.5～5.5%
Bond with K-N α soluble glass of high modulus.
4, welding procedure according to claim 1, the chemical analysis that it is characterized in that described BT-2 welding rod deposited metal is: C0.40～0.46%, Si0.16～0.22%, Mn1.0～1.4%, Cr1.5～1.7%, Ni4.0～4.5%, W0.65～0.75%, V0.30～0.37%, Mo1.8～2.20%.
5, welding procedure according to claim 1 is characterized in that the edge of bevel for welding and bottom angle are by 90 ° of finishings.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 87101406 CN1012145B (en) | 1987-11-19 | 1987-11-19 | Welding rods and technolgy for repair welding of white-iron roller |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 87101406 CN1012145B (en) | 1987-11-19 | 1987-11-19 | Welding rods and technolgy for repair welding of white-iron roller |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1033167A CN1033167A (en) | 1989-05-31 |
| CN1012145B true CN1012145B (en) | 1991-03-27 |
Family
ID=4813395
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 87101406 Expired CN1012145B (en) | 1987-11-19 | 1987-11-19 | Welding rods and technolgy for repair welding of white-iron roller |
Country Status (1)
| Country | Link |
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| CN (1) | CN1012145B (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1067312C (en) * | 1996-01-10 | 2001-06-20 | 山东工业大学 | Cold-welding technique for partially repairing high-carbon alloy steel roller |
| CN1315613C (en) * | 2005-01-24 | 2007-05-16 | 燕山大学 | Build-up welding electrode for composite double-metal big gear re-manufacturing technology |
| CN100343008C (en) * | 2005-07-06 | 2007-10-17 | 湘潭大学 | High chromium rust free, wear resistance cored welding wire |
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-
1987
- 1987-11-19 CN CN 87101406 patent/CN1012145B/en not_active Expired
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1067312C (en) * | 1996-01-10 | 2001-06-20 | 山东工业大学 | Cold-welding technique for partially repairing high-carbon alloy steel roller |
| CN1315613C (en) * | 2005-01-24 | 2007-05-16 | 燕山大学 | Build-up welding electrode for composite double-metal big gear re-manufacturing technology |
| CN100343008C (en) * | 2005-07-06 | 2007-10-17 | 湘潭大学 | High chromium rust free, wear resistance cored welding wire |
Also Published As
| Publication number | Publication date |
|---|---|
| CN1033167A (en) | 1989-05-31 |
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