TW574380B - Submerged-arc welding point with large heat input, method for producing the welding point, steel solder wire used by the method, and solder flux - Google Patents

Description

Economic Zou 1 huihui (printed by industrial and consumer cooperation tl 574380 A7 B7 V. Description of the invention (i) (Technical field to which the invention belongs) The present invention relates to high heat input submerged arc welding. In particular, there are suitable welding joints (welding joints) for submerged arc welding with high heat input above 150 kJ / cm, and the steel wire (welding wire) used for this joint. ) And welding flux (hereinafter referred to as "flux") 〇 In welding construction, always has been strongly required to improve the welding energy rate. In order to improve the welding efficiency is usually to increase the welding input heat. However, usually increase the welding input heat The toughness of the welded metal will decrease. The reason for this is that as the input heat of the weld increases, the cooling rate of the welded portion will decrease, which will cause the structure of the welded metal to coarsen. Submerged Welding It is a method of continuous welding by using the arc occurring in the flux dispersed in the groove to be welded. The arc is widely used in the field of joining thick steel plates such as shipbuilding, bridges, pressure vessels, industrial machinery, etc. as an efficient welding method that can obtain deep melting and large welding volume. However, due to submerged arc welding The legal system uses a large current to perform welding, so the welding input heat becomes high, and the toughness of the welded metal tends to decrease. For this problem, for example, Japanese Patent Gazette No. 7-3 2 8 7 9 3 is disclosed, which lies in the potential In arc welding, a technique is added in which boron (B) oxide is added to the flux, and the weld metal contains boron (B) through the flux in order to improve the toughness of the weld metal. JP 7-3 2 8 7 9 3 The disclosed technology applies the paper size of submerged arc welding to the Chinese National Standard (CNS) A4 (210X297 mm) (please read the precautions on the back before filling this page)

574 380380 A7 _____ B7 _ 5. Description of the invention (6) B conversion contains 0 · 〇3 ~ 0.30 mass compound. (A) group: one or two of Mo powder, molybdenum iron powder, and Mo compound, totaling 0.2 to 2.0% by mass for the total amount of flux in terms of Μo, (B) group: Nb powder, niobium One or two or more of iron powder and Nb compound, based on Nb conversion, for one or two or more groups selected from the total flux of 0.02 to 0.15%, or further containing mass percent for the total amount of flux Whereas 8 i〇2: 1〇 ~ 2 8%, CaC〇3: 5 ~ 15%, Mg〇: 15 ~ 38%, Al2O3: 3 ~ 20%, Ti〇2: 2 ~ 10%, C a F 2: 2 ~ 10%, atomized iron powder, MO powder, molybdenum iron powder, Nb powder and metal powder other than ferroniobium powder: one or two or more selected from 2 to 8% are characteristic Submerged arc welding joint manufacturing method. (Explanation of a suitable embodiment) In order to achieve the above-mentioned problem, the present inventors joined submerged arc welding of 490 to 520 MPa grade steel materials to be welded by submerged arc welding with a high heat input of 150 kJ / cm or more. Careful consideration of various factors related to the toughness of the weld metal obtained. The results show that the toughness of the weld metal obtained by submerged arc welding with a high heat input of more than 150 k J / cm, is very sensitive to nitrogen, and there is a small change in the amount of nitrogen. The toughness is a case where the toughness is significantly deteriorated. In particular, when the material to be welded is a steel with a small Ti and Nb content, the microstructure of the welded metal will be coarsened by the increase of a small amount of nitrogen. (Please read the precautions on the back before filling this page) The paper size printed by the Intellectual Property Bureau's Consumer Cooperatives of the Ministry of Economic Affairs applies the Chinese National Standard (CNS) A4 specification (210 × 297 mm) -9-574380 A7 __ B7 _ V. Description of the invention (7) Significant degradation It is presumed that when a steel material with a small T i content is insufficient for supplying T i to the weld metal, it is difficult to adjust the fixed N amount. (Please read the precautions on the back before filling this page) The inventors and others based on the above-mentioned knowledge and discussed the results, and thought that although the welded material is a steel with a small content of Ti and Nb, they want to obtain stability For high-toughness submerged arc welding of metals with high heat input, it is necessary to appropriately adjust the welding on the one hand. The N content of the steel wire is also contained in the steel wire in an appropriate amount corresponding to the N content of the steel wire. The amount of T'i is therefore implemented, and a fine welded metal structure can still be obtained under welding with high heat input. Furthermore, the inventors and others have conducted in-depth reviews on submerged arc welding metals with high heat input in order to regain stability and high toughness. First, the relationship between the amount of iron in the grain boundary of the weld metal and the energy absorbed by the Charpy (impact test) and the toughness 冲击 (v E 0). For the Ti content of 0.0006% by mass or less, the Nb content is 0. The steel with a thickness of 40mm or less with a mass of less than 0.12% is based on the welding metal welded by a submerged arc joint with a high heat input below 150 kJ / cm, and the results of the investigation are shown in section 4 Figure. Consumption cooperation with employees of the Intellectual Property Bureau of the Ministry of Economic Affairs printed the new insight obtained from Figure 4 to set the amount of grain boundary fertilizer and iron in the welded metal to 15% by area or less, preferably 10% by area or less It can stably impart high toughness. The relationship between the mass% ratio of B / N in the weld metal and the amount of iron produced at the grain boundary is also discussed. The results are shown in FIG. 5. Figure 5 also clearly shows that it is ascertained that because the steel wire contains Mo, Nb -10- This paper size is applicable to the Chinese National Standard (CNS) A4 specification (210X297 mm) 574380 Workers of the Intellectual Property Bureau of the Ministry of Economic Affairs Consumption cooperative prints A7 ____B7 _V. Invention description (8), etc. The reason is that an appropriate amount of Mo, Nb, etc. is added to the welding metal, and the mass% ratio of B / N is adjusted to achieve the control of the welding metal. It is possible that the amount of iron produced at the grain boundary is 15.0 area% or less, and the most suitable value is 10 · 0 area% or less. The adjustment of the amount of solid-solved nitrogen in the welded metal can be improved to a certain extent by using a steel wire (fused steel wire) containing T i or N b, in order to use a welded steel that does not contain T i or N b It is very difficult to adjust the wire, which results in significant deterioration of the toughness of the weld metal, especially the deterioration of the toughness of the weld metal using a welded steel wire without T i. Generally speaking, among the 490 ~ 52OMPa grade steels with high versatility, the Ti content is 0.006 mass% or less, and the Nb content is 0.012 mass% or less. Ti is a representative steel with a small Nb content. Therefore, it is often difficult to obtain a stable and high-toughness weld metal. In the welding of such steels, the requirements for obtaining a stable weld metal with excellent toughness are very demanding. Based on the above knowledge, the inventor thought of the result of further discussion. When the material to be welded is a steel with a small content of Ti and Nb, especially a steel wire for welding without T i is used to implement high heat input. Under submerged arc welding, if iron powder added to the welding flux is used and N atomized iron powder with a mass of 4 or less is less than 0.030 mass, it is possible to obtain a stable and high-toughness welding metal. And for the submerged arc welding metal with high heat input, the stability and the higher toughness of the stomach lies in the flux. It is suitable to contain Mo, Nb, and the like. Add appropriate amounts of Mo, Nb, etc. to the weld metal (please read the precautions on the back before filling this page). Order the paper. This paper size applies the Chinese National Standard (CNS) Α4 size (210X297 mm) -11 -574380 A7 ____B7 V. Description of the invention (11) (Please read the precautions on the back before filling out this page) %%, because the structure of the welded metal easily becomes the upper toughness (Bainite), which causes the toughness to deteriorate, so they are designated as M 〇: 0 · 1 0 to 0.50%, Nb: 0.1 to 0.200% is suitable. Furthermore, N i increases the toughness of the ferrous phase and the toughness of the weld metal. This effect is significant when it contains more than 0.5%. On the other hand, when it exceeds 1.00%, low-temperature cracking occurs. Therefore, Ni is preferably set to a range of 0.05 to 1.00%. The amount of grain boundary ferrous iron in the weld metal: 15 · 0 area%. In order to further impart stability and high toughness to the submerged arc weld metal with high heat input, it is not just to adjust the composition of the weld metal. It is only necessary to reduce the amount of iron in the grain boundaries of the welded metal to less than 15.0 area%. In order to achieve stable and high toughness, it is necessary to make the grain boundary fertilizer and iron content in the welded metal less than 10.0% of the area. Printed by the Consumers' Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs, and the amount of grain boundary fertilizer and iron in the weld metal is measured by observing the weld metal. The observation system uses an optical microscope and an electron microscope. 0 0 times to implement. After observing the mirror surface by honing, it is etched with an etching solution, and the observation image is subjected to image processing using an image analysis processing device to obtain the amount of grain boundary ferrous iron in the welded metal. The measurement of the amount of iron produced at the grain boundary in the welded metal is not particularly limited, and the usual measurement methods can be applied. 〇.60 ^ B / N ^ 1.20 • 14- This paper size is applicable to Chinese National Standard (CNS) A4 (210X297 mm) 574380 A7 _____B7 _ V. Description of the invention (12) (Please read the notes on the back before filling in (This page) In order to reduce the amount of grain boundary fertilizer and iron in the weld metal to less than 10 · 0 area%, it is necessary to adjust the amount of solid solution N of the weld metal, and it is necessary to add an appropriate amount in the weld metal. Mo, Nb, etc. At the same time, it is necessary to adjust the mass% ratio of B / N in the weld metal. According to the B system, the analysis of the formation of coarse grain boundary ferrous iron from the grain boundary of Vostian is restricted to increase the toughness of the welded metal. When the mass% ratio of B / N is less than 0.6, the effect is insufficient, and stable and further high toughness cannot be obtained. Since the B / N mass% ratio exceeds 1.20, the toughness is deteriorated. Therefore, the B / N mass% ratio in the weld metal is set to be equal to or higher than 0.60, and preferably equal to or lower than 1.2. The first method for obtaining the above-mentioned welded metal of the present invention is a method of limiting a welded steel wire (steel wire). The flux for welding at this time does not need to be particularly limited, and any conventionally known firing flux can be used. First, the reason for limiting the steel wire composition of the steel wire for submerged arc welding with high heat input according to the present invention will be explained. (The mass percentage in the following composition is only expressed as%.) C: 0.03 to 0.10% Printed by the Consumer Cooperatives of the 4th Bureau of the Ministry of Economic Affairs and the Consumer Cooperative, C is an element that increases the strength of the weld metal. The present invention is to ensure the desired weld metal The strength lies in that the steel wire contains 0.30% or more. If the C content in the steel wire is less than 0.3%, it is difficult to obtain the specified strength of the weld metal, and the partial pressure of CO in the arc environment during welding becomes low, and N is drawn from the atmosphere to make the weld. The N content of the metal may increase. On the other hand, if the content exceeds 0 · 10%, the content of C in the weld metal increases, the toughness of the weld metal will deteriorate, and high temperature turtles are prone to occur. -15- This paper applies the Chinese National Standard (CNS) A4 specification (210X297) (Mm) 574380 A7 __B7_ V. Description of the invention (16) The remainder other than the above components are Fe and unavoidable impurities. As an unavoidable impurity, 〇: 〇 0050% (please read the precautions on the back before filling in this page) The following, P: 0 · 020% or less, S: 〇〇〇〇〇% or less In the steel wire of the present invention, from the viewpoint of improving feedability (feedability) and rust resistance, it is preferable to perform copper plating on the surface of the steel wire. In addition, the steel wire of the present invention is suitable for submerged arc welding of low heat input with input heat below 150 k J / cm without any problem. Of course, a weld metal having excellent toughness can be obtained stably. Furthermore, the welding flux used when the above-mentioned welded steel wire of the present invention is to be used is not particularly limited. Generally, any one of conventionally known welding fluxes can be used, but it is preferable to use a solder containing 0.1 to 1 0 mass% sintered flux of boron oxide. Therefore, the supply of B to the weld metal suppresses coarsening of the structure and prevents deterioration of toughness. Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs. The composition of fluxes other than boron oxide is not particularly limited, but 3%: 15 ~ 28%, Mg0: 15 ~ 38%, iron powder: 15 ～ 35%, CaC〇3: 5 ～ 15%, Αΐ2〇3 ·· 5 ～ 20%, Ti〇2: 2 ～ 10%, C a F 2: 2 ～ 10%, and metal powder other than iron powder Welding metals with excellent toughness can still be obtained at more than 8% by mass, but the cost of welding materials increases and the production cost of welding joints becomes expensive. Therefore, metal powders other than iron powder should contain 8% or less. Furthermore, the flux in the present invention is not limited to the above, and is specified in JISZ 3 3 5 2 flux, as long as it is a flux with good workability--19-This paper size applies Chinese National Standard (CNS) A4 specifications ( 210X297 mm) 574380 A7 B7 V. Description of the invention (17) Of course, iron powder is also available. (Please read the precautions on the back before filling this page.) When adding iron powder to the flux, it is better to use iron powder with N: 〇. 〇 〇 30% by mass. The N: 0.0030 mass% or less of the iron powder is preferably contained in the flux in an amount of 20 to 45 mass%. When the N content in the iron powder exceeds 0.030% by mass, the N content of the weld metal obtained increases, which shows that it is difficult to securely secure high toughness. The N content in the iron powder is more preferably from 0.0025 mass% or less. The iron powder in the flux is moved to the melting pool during welding to increase the welding speed. It contributes to the improvement of welding efficiency and the reduction of welding input heat. N in the flux: 0. 0030 mass% or less of iron powder When the content is less than 20% by mass, the above-mentioned effects are small. On the other hand, when the content is more than 45% by mass, the arc tends to become unstable and the appearance of the bead deteriorates. For this reason, the content of iron powder N: 0.0030 mass% or less is suitable for the entire flux and 20 to 45 mass%. In addition, there is a method for limiting the composition of the welding flux as the second method for obtaining the above-mentioned welding metal of the present invention. Printed by the Ministry of Economic Affairs, the 4th Bureau of Wisdom Wealth Cooperatives, and the steel wire for welding at this time does not need to be specially limited. Generally known steel wires for submerged arc welding can be used. The flux for submerged arc welding of the present invention is a firing flux, which is suitable for submerged arc welding with a high heat input above 15 Ok J / cm. First, the reasons for the composition of the submerged arc welding flux of the present invention are limited. Do-20- This paper size applies Chinese National Standard (CNS) A4 specification (210X297mm) 574380 Printed by A7 B7, Consumer Cooperative of Intellectual Property Bureau of the Ministry of Economic Affairs 5. Description of invention (19) It is used for flux raw materials, so The advantage of reducing the combined dosage of flux granulation. The atomized iron powder is powdered by spraying (atomizing) the molten iron, and is usually made into a product by a process of dehydration-drying-disintegration-classification-refined reduction-disintegration-classification. The N content of a normal atomized iron powder is about 0. 5%. Of course, to make low-N atomized iron powder below 0. 0 30%, it is necessary to reduce the amount of N in the molten iron. However, it is necessary to adjust the reduction temperature and cooling temperature of the finishing reduction process appropriately. Compound B: 0.03 ~ 0 · 30% in terms of B. B refers to the fact that it travels in the weld metal during welding, and suppresses the formation of coarse < The effect is to increase the toughness of the weld metal. B series can achieve this effect cheaply. This effect is remarkable when the B compound is contained in a total amount of 0.30% or more of the flux in terms of B. on the other hand. When the B compound is contained in a total amount of 0.30% or more of the flux in terms of B, the toughness of the weld metal tends to deteriorate. (A) group: one or two or more of 〇 powder, molybdenum iron powder, and 〇 compound powder ·· Mo totals 0 · 2 ~ 2 · 0% by mass (B) group: Nb powder, iron niobium One or two or more of the powder and Nb compound powder: one or a group of a total of 0.02 to 0.15% in Nb conversion. (A) group is order Mo, (B) group is order Nb, which is included in the supply source for welding metal. Mo and Nb are transferred to the welding gold during welding (please read the precautions on the back before filling this page) This paper size applies to the Chinese National Standard (CNS) A4 specification (210X297 mm) · 22 574380 A7 B7 V. Description of the invention (2G) (Please read the precautions on the back before filling this page). The effect of inhibiting the formation of coarse fat iron produced in Vostian body and grain boundary, and improving the toughness of welded metal. The above-mentioned effect can be achieved by selecting one or two groups from the (A) group and the (B) group as necessary. The above-mentioned effect is to select one or more of Mo powder, molybdenum iron powder, and Mo compound powder from the group (A), and the total amount of Mo conversion is more than 0%, and the N b powder of the (B) group and ferroniobium powder. One or two or more of the N b compound powders, which have a total content of 0.02% or more in terms of Nb conversion, can have a significant effect. On the other hand, one or two or more of the Mo powder, molybdenum iron powder, and Mo compound powder of the (A) group, totaling more than 2.0% in terms of Mo, and the Nb powder, ferroniobium powder, and Nb of the (B) group One or two or more of the compound powders, totaling more than 0.0 in terms of N b; [5%, when contained separately in excess, the structure of the weld metal tends to become tougher at the top, and the toughness of the weld metal is deteriorated. The trend. In addition to the above ingredients, S i 〇2: 10 ~ 28%, printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs ^

CaC〇3: 5 to 15%, Mg〇: 15 to 38%, Al2〇3: 3 to 20%, Ti〇2: 2 to 10%, C a F 2: 2 to 10%, atomized iron powder , M o powder, molybdenum iron powder, N b powder and metal powder other than silver iron powder: one or two or more selected from 2 to 8%. The flux for welding according to the present invention contains one or more of the above-mentioned iron powder (atomized iron powder), B compound powder, and Mo powder, molybdenum iron powder, Mo compound powder, Nb powder, iron niobium powder, Nb One of the compound powders or this paper size applies the Chinese National Standard (CNS) A4 specification (210X297 mm) -23- 574380 Employees of Intellectual Property Bureau of the Ministry of Economic Affairs of the consumer Ti printing A7 B7 5. Invention description (21) Two or more kinds, In addition to Si〇2, CaC03, Mg〇, A 1 2 0 3, T i 0 2, CaF2, and atomized iron powder, Μο powder, molybdenum iron powder, N b powder, iron niobium powder One or more of the powders are suitable. S i〇2 is an effective ingredient of the slag-forming agent. It is desirable to include it in order to adjust the viscosity of the slag. When the content of S i〇2 is less than 10%, the melting point of the generated slag tends to increase. On the other hand, when the content is more than 28%, the melting point becomes too low and the appearance of the bead is prone to be disturbed. , And the amount of oxygen of the weld metal increases, and the toughness of the weld metal tends to deteriorate. Therefore, S i 0 2 is preferably 10% to 28%. The CaC03 system is decomposed into CaO and C02 during welding, so that the C02 gas shields the welding metal from the outside air, and at the same time, reduces the hydrogen partial pressure in the welding environment, and effectively acts to prevent hydrogen. Intrudes into weld metal. In addition, C a 0 is an alkaline component, which raises the slag and has the effect of improving the toughness of the weld metal. When the content of C a C03 is less than 5%, the shielding effect caused by the above C02 gas cannot be seen. There is a tendency for hydrogen cracking resistance to decrease. On the other hand, if it is contained more than 15%, the amount of CO2 gas will increase, and the welding workability will deteriorate the appearance of the bead. Therefore, it is appropriate to set C a C 0 3 to a range of 5 to 15%. M g 0 has the effect of preventing excessive flow of the flux. It also has the effect of stabilizing the bead shape when welding with high heat input. In addition, Mg 0 increases the alkalinity of the slag and reduces the oxygen content in the weld metal. (Please read the precautions on the back before filling out this page.) This paper size is applicable to China National Standard (CNS) 8-4 (210X297 mm ) -24- 574380 Intellectual Property Bureau of the Ministry of Economic Affairs g (industrial-consumer cooperation ti printed A7 __ B7 V. Invention Description (22) A component useful for improving the toughness of welded metals. The content of Mg 0 is less than 1 5 The above effect cannot be seen at%. On the other hand, when it is contained in excess of 38%, the melting point is too high, and the appearance of the bead tends to deteriorate. Therefore, it is appropriate to set the range of 15 to 38%. A 1 2 03 can increase the melting point of the slag without reducing the viscosity, so it is an effective ingredient in adjusting the melting point of the slag. When the content of A 1 2 03 is less than 3%, the above will not appear. Effect, on the other hand, if it is contained more than 20%, the melting point of the slag is too high to cause uneven bead width or deterioration of appearance. Therefore, the content of A 1 2 03 is in the range of 3 to 20%. It is suitable. T i〇2 can improve the slag fluidity, in order to improve the peelability of the slag. Part of the arc cavity is reduced and migrates in the weld metal as Ti, which effectively improves the toughness of the weld metal. However, when the content of Ti is less than 2%, the above effect will not appear, and On the other hand, if the content exceeds 10%, the appearance of the bead will be degraded. Therefore, T i〇2 is preferably set to a range of 2 to 10%. C a F 2 can be increased without increasing the melting point. The alkalinity of the slag is effective for adjusting the oxygen content of the weld metal. When the content of C a F2 is less than 2%, the effect is reduced. On the other hand, when it exceeds 10%, the viscosity of the slag is too low. The appearance of the channel will be deteriorated. Therefore, the CaF.2 system is preferably set to a range of 2 to 10%. Metal powders other than atomized iron powder, MO powder, molybdenum iron powder, Nb powder, and iron niobium powder are used. It is added as a source of deoxidizer or alloy element, but if its content is less than 2%, it will be difficult to ensure the toughness of the weld metal and the appearance of the weld bead (please read the precautions on the back before filling this page) This paper size is applicable to China National Standard (CNS) A4 specification (210X297 mm) 25- 574380 Intellectual Property Bureau of the Ministry of Economic Affairs Printed by Fei Cooperative A7 ___B7 V. Invention Description (23) There is a tendency to deteriorate. On the other hand, if it is contained in more than 8%, the oxygen content of the weld metal will be reduced, and the structure of the weld metal will become toughened or the main body of the Asa Intermediate The toughness of the welded metal tends to decrease, so the metal powder other than atomized iron powder, MO powder, molybdenum iron powder, N b powder, and ferroniobium powder is set to a range of 2 to 8%. This metal powder is suitable. There are ferromanganese powder, ferrosilicon powder, ilmenite powder, manganese, titanium, etc., and the metal powder is in the form of a foil other than powder, and needle-shaped. In the flux of the present invention, the above-mentioned flux raw materials are quantitatively blended in the above-mentioned range, mixed with the bonding agent, and then granulated and fired. Although the granulation method is not particularly limited, it is convenient to use a rotary granulator, an extrusion granulator, or the like. After granulation, the whole granules are removed by removing dust, coarse granules, etc., and it is suitable to make granules with an average diameter of 0.075 to 5 mm. As the binding agent, an aqueous solution of polyvinyl alcohol, an aqueous solution of sodium silicate, an aqueous solution of potassium silicate, and a mixed solution of an aqueous solution of sodium silicate and an aqueous solution of potassium silicate are suitable. The added amount of the binder is preferably about 50 to 30 Occ per 1 kg of the flux raw material. In addition, the flux for welding according to the present invention is naturally applicable to submerged arc welding with a low heat input of less than 150 kJ / cm. It is possible to obtain a welded metal having excellent toughness stably. Further, the steel wire for welding when the flux for welding according to the present invention is used is not particularly limited, and any steel wire for submerged arc welding may be used as long as it is conventionally known. Next, there is a high heat input with excellent toughness of the welded metal part (please read the precautions on the back before filling this page) This paper size applies to Chinese National Standard (CNS) A4 specification (210X297 mm) -26- 574380 A7 _____B7 _ 5. Description of the invention? 4) Manufacturing method of submerged arc welding joint. (Please read the precautions on the back before filling this page) The manufacturing method of the submerged arc welding joint with high heat input according to the present invention is to use steel with low T i, N b content as the welding material, and Submerged arc welding with a high heat input of more than 150 k J / cm is particularly effective for welding metals with high toughness when performing welding. The steel material used as the material to be welded has a T i content of 0.0006% by mass or less, an Nb content of 0.012% by mass or less, and preferably a base metal composition having an N content of 0.0005% or less. Of steel. Other ingredients include C ·· 〇. 07 ~ 18%, Si: 0.40% or less, Μη: 1.00 ~ 1.60%, P: 0.020% or less, S: 0.10%, or A1: 0 · 0 5 The content is preferably 0% or less, and it may contain V in addition to the above components. The steel materials referred to in the present invention include: thick steel plates, shaped steel, steel pipes, and rod pipes. After the above-mentioned steel material is subjected to a predetermined groove processing (open-first processing), flux is dispersed in the welding groove, and the above-mentioned submerged arc welding steel wire with high heat input is used, and the heat is inputted by 150 kJ / cm. The above-mentioned submerged arc welding with high heat input performs welding. Printed by the Consumer Cooperative of the 4th Bureau of the Ministry of Economic Affairs, the submerged arc welding of the present invention is a conventional welding method including submerged arc welding of multiple electrodes, which can be applied without special limitation, and the welding conditions do not need to be particularly limited. Based on the above-mentioned material to be welded and the material to be welded, the welded joint (welded structure) is produced by submerged arc welding with a high heat input of 150 k J / cm or more and a heat input. And the obtained melting -27- This paper size is applicable to the Chinese National Standard (CNS) A4 specification (210X297 mm) 574380 A7 B7 V. Description of the invention? 5) The welding metal of the joint (welding structure) will become a high toughness welding metal. (Please read the precautions on the back before filling in this page) (Example 1) On the 490 MPa grade a steel sheet (plate thickness: 25mm, 40mm) of the base metal composition shown in Table 1, give 1A The welding groove of the shape shown in FIG. 1B is processed, and submerged arc welding of one channel is used to make a welded joint. When the thickness of the steel plate is 2.5 mm, the shape of the welding groove is an L-shaped welding groove, the angle of the welding groove is 40 °, and the root surface of the weld is 2 mm. In addition, the welding groove shape of the steel plate with a thickness of 40 m m is a Y-shaped welding groove. The welding groove angle is 35 °, and the root surface of the welding is set to 3 mm. Submerged arc welding is performed using a two-electrode submerged arc welding machine. The welding conditions shown in Table 2 were performed using steel wires (welding rods) for welding shown in Table 3. The flux used is a commercially available iron-added powder firing flux containing 0.4% by mass of boron oxide containing the composition shown in Table 4. The iron powder contained in the flux is made of sponge iron powder. Iron powder, welding input heat system is 153 kJ / cm when the plate thickness is 25mm, 270kJ / cm when the plate thickness is 40mm, and it is printed by the employee consumer cooperative of the Bureau of Intellectual Property, Bureau of Economic Affairs, Ministry of Economic Affairs. The test piece was taken at the positions shown in Figures 2A and 2B of the center portion in the longitudinal direction of the welding. The tensile strength, toughness and tensile test of the welded metal were investigated in accordance with JIS Z 3111, and the impact test was implemented in accordance with JIs Z 3112 to obtain the tensile strength TS, and 0 ° C, — 20 ° c's Charpy absorbed energy 値 vE〇, VE-20. This paper size applies to China National Standard (CNS) A4 specification (210X297 mm) -28- 574380 Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs A7 _____B7 V. Description of the invention? 6) These results are compiled in Table 5. In the examples of the present invention, the v E 0 of the weld metal is 2 7 J or more, and a weld joint having an excellent toughness equal to or higher than the general level of the base metal specification is obtained. Welding joints obtained by using steel wires containing Mo and Nb within the scope of the present invention (welding joints No. 3, No. 0.4, No. 0.5) are welded metal systems v E-2 0 is more than 2 7 J's excellent toughness. On the other hand, a comparative example (welded joint No. 0.6) in which the N content of the steel wire is far outside the scope of the present invention, that is, the weld joint has v E 〇 less than 27 J, and the toughness is deteriorated. In addition, the Ti content of the steel wire deviated from the comparative example (welding joint No. 7) of the present invention, that is, the structure was coarsened, and the vEo of the welding metal was less than 27 J, indicating that the toughness was deteriorated. In addition, the comparative examples (weld joint No. 6, No. 7, No. 8) where the Ti / N of the steel wire deviated from the scope of the present invention were v E 〇 less than 2 7 J of the weld metal, and the toughness deteriorated. Further, a comparative example (welded joint No. 9) having a high Ti content outside the scope of the present invention is a structure in which the upper part becomes a toughened main body, and v E 0 of the welded metal is less than 2 7 J, and the toughness is deteriorated. ) Further, a comparative example (welded joint No. 10) where the M η content of the steel wire is low and out of the scope of the present invention, and a comparative example (welded joint N) which is out of the scope of the present invention is high in the Si content of the steel wire 〇. 1 1) The ferrous iron of the weld metal is coarsened, and v E 〇 is less than 2 7 J, which shows the deterioration of the toughness of the weld metal. (Please read the precautions on the back before filling this page) This paper size is applicable to the Chinese National Standard (CNS) A4 specification (210X297 mm) -29- 574380 A7 B7 5. Description of the invention? 7) Table 6 shows the composition of the weld metal, the mass% ratio of B / N in the weld metal and the amount of iron produced at the grain boundary. In the example of the present invention, the amount of grain boundary fertilizer and iron in any of the welded metals is less than 15% by area, and the fusion is obtained (please read the precautions on the back before filling this page). The v EQ of the welded metal is 2 7 Welding joints with excellent toughness above J. Furthermore, using a steel wire containing M 0, N b within the scope of the present invention, and the B / N mass% ratio in the welded metal can be within the scope of the present invention. Welded joints (welded joints No. 3, No. 4, No. 5) The amount of grain boundary ferrous iron in the welded metal is less than 10% by area, and v E-2 with welded metal exceeds 2 7 J's excellent toughness. (Example 2) A 490 MPa grade P a steel plate (plate thickness t: 40 mm) and a TMCP steel plate (plate thickness t: 60 mm) for the base material composition shown in Table 7 were applied as shown in Table 3. As shown in the welding groove processing, the welding joint is implemented by submerged arc welding of one channel. The shape of the welding groove is a Y-shaped welding groove. Welding groove angle 35 °, welding root surface d (mm), plate thickness t: 40mm, printed by the Consumer Cooperative of the 4th Bureau of the Ministry of Economic Affairs, 2mm when printed, and 3mm when plate thickness t: 60mm. Submerged arc welding uses a two-electrode submerged arc welding machine. The welding conditions shown in Table 8 are used, and the steel wire for welding is composed of the steel wires shown in Table 9. The flux is mixed with the raw materials to have the composition as shown in Table 10, and is kneaded together with a sodium silicate aqueous solution. After granulation, it is fired under the conditions of 500 ° CX 1 5 mi η, and the particle diameter is 3 mm or less. The size of the paper containing boron oxide and iron is applicable to the Chinese National Standard (CNS) A4 specification (210X 297 mm) -30- 574380 A7 __ B7 5. Description of the invention? 8) Powder flux. For the iron powder added to the flux, iron powders having the nitrogen content shown in Table 11 were used. When the welding input thermal system is 40mm thick, it is 269 kJ / cm, and when it is 60mm thick, it is 549kJ / cm. (Please read the precautions on the back before filling in this page.) The weld joint obtained as described above was tested from the position shown in Figure 2A and Figure 2B of the central part of the weld length direction in the same manner as in Example 1. Sheet, the tensile strength and accessibility of the welded metal were investigated. The tensile test was performed in accordance with JISZ 3 1 11 as in Example 1. The impact test was performed in accordance with JIs Z 3112. The tensile strength TS and the temperature between 0 ° C and 2 0 ° C were determined. Xia's absorbed energy 値 v E ◦, VE-2 〇. The results are shown in Table 12-2. The welded joints using the steel wire and flux of the examples of the present invention are such that v E 〇 of the weld metal satisfies 100 mm or more at a thickness of 40 mm and 47 or more at a thickness of 60 mm. v E-2 0 meets the requirements respectively, the plate thickness is 40J or more and 80J or more, and the plate thickness is 60mm or more, it is 50 J or more. Welding joints with excellent toughness are obtained. In addition, Table 1 3 shows the composition of the weld metal, the mass% ratio of B / N in the weld metal, and the amount of iron produced at the grain boundary. The Ministry of Economic Affairs and the Intellectual Property Bureau of the 8th Industrial Cooperative Cooperative printed and used the steel wire and flux of the present invention, and the B / N mass% ratio of the welded metal became a welded joint within the scope of the present invention (welded joint No. 2-1 , 2 — 2, 2-3, 2 — 4, 2 — 5) is the grain boundary fertilizer in the welded metal. The amount of iron produced is less than 10% by area. A weld metal having very excellent toughness was obtained. -31-This paper size is in accordance with Chinese National Standard (CNS) A4 (210X297 mm) 574380 Printed by the Consumers ’Cooperative of Intellectual Property of the Ministry of Economic Affairs A7 B7 V. Description of the invention? 9) (Example 3) The 490 MPa grade P a steel plate (plate thickness t: 40 mm) and the TMCP steel plate (plate thickness t: 60 mm) for the base material composition shown in Table 7 were given as shown in Table 7. The welding groove in the shape shown in Figure 3 is made by submerged arc welding of 1 channel. The welding groove shape is a Y-shaped welding groove with a welding groove angle of 35 ° and a welding root surface d (mm ), That is, the plate thickness t: 2mm at 40mm, and the plate thickness t: 60mm, it is set to 3mm. The submerged arc welding system uses a two-electrode submerged arc welding machine, and the welding conditions shown in Table 14 Welding is performed by using the steel wire for welding composed of the steel wires shown in Tables 1 and 5 and using the flux shown in Table 16 for welding. The flux is mixed with the raw materials to form the composition shown in Table 16, and mixed with sodium silicate aqueous solution (additional amount of about 2 0 cc per 1 kg of flux)-after mixing and granulating, at 500 ° CX 1 5 The firing is performed under the conditions of mi η, and the particle diameter is set to 3 mm or less. The chemical composition in Table 16 totals less than 1000% by mass, but the remainder is the solid content of sodium silicate and inevitable impurities. The iron powder to be added to the flux was atomized iron powder, and atomized iron powder having the nitrogen content shown in Table 17 was used. Welding input heat, plate thickness 4〇111111, 269 dagger] / (: 111, plate thickness 6〇111111, 521 k J / cm 〇 For the welded joint obtained as described above, the 2A from the center of the welded length The test piece was taken at the position shown in Figure 2B, and the tensile strength and toughness of the welded metal were investigated. (Please read the precautions on the back before filling out this page.) This paper size applies the Chinese National Standard (CNS) A4 specification. (210 > < 297 mm) -32- 574380 A7 _ B7_ V. Description of the invention? ◦) (Please read the notes on the back before filling this page) The tensile test is to take the test piece from the position shown in Figure 2A According to JIS Z 3111, the tensile strength TS was obtained. In the impact test, a test piece was taken from the position shown in Fig. 2B, and the test was performed in accordance with JISZ 3 1 12. The Charpy absorbed energy 値 v E 〇0 at 0 ° C was obtained. These results are summarized in Table 1 8 Express it. In the example of the present invention, v E 0 of all welded metals satisfies 2 7 J or more, and a welded joint having excellent accessibility is obtained. A comparative example that deviates from the scope of the present invention is that the toughness of the weld metal is significantly lowered. Table 19 shows the composition of the weld metal, the ratio of B / N in the weld metal, and the amount of iron produced at the grain boundary. The amount of grain boundary ferrous iron in the weld metal using the flux of the present invention is not more than 15 · 0 area%, and a weld metal having excellent toughness is obtained. In addition, the ratio of B / N mass% in the weld metal is a weld joint (weld joint No. 3-5, No. 3-9, 3-10) within the scope of the present invention, and the grain boundary fertilizer in the weld metal The amount of grain iron produced is 10% by area or less, and has better toughness. When printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs according to the present invention, submerged arc welding with high heat input with welding input heat of 15 Ok J / cm or more is used to weld steels with low contents of T i, .Nb, etc. In this case, still, a stable welding metal having excellent toughness can be obtained, which can significantly improve the welding efficiency, and can achieve significant effects in the industry. This paper size applies Chinese National Standard (CNS) A4 specification (210X297 mm) -33- 574380 A7 B7 V. Description of invention? 1) Brief Description of Drawings FIG. 1A is a schematic diagram showing the outline of the shape of the welding groove of the welded joint used in the first embodiment of the present invention. Fig. 1B is a schematic diagram showing the outline of the shape of the welding groove of the welded joint used in the first embodiment of the present invention. Fig. 2A is a diagram for explaining the mode of taking positions of the tensile test pieces used in Examples 1 to 3. Fig. 2B is an explanatory diagram for explaining the mode of taking positions of the impact test pieces used in Examples 1 to 3. Fig. 3 is a schematic view showing the outline of the shape of the welding grooves of the welded joints of the second and third embodiments. Fig. 4 is a graph showing the relationship between the amount of iron produced at the grain boundary in the weld metal and the absorbed energy (v E.) of Charpy. Fig. 5 is a graph showing the relationship between the B / N mass% ratio in the weld metal and the amount of iron produced at the grain boundary. (Please read the notes on the back before filling out this page) Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs This paper applies the Chinese National Standard (CNS) A4 specification (210X297 mm) -34- 574380

A B V. Explanation of invention? 2) Bureau of Wisdom Wealth, Ministry of Economic Affairs a (printed chemical composition (mass%) by industrial and consumer cooperatives) > 1 0.030 0.030 0.0021 0.0030 0.0040 g 0.003 0.008 0.005 0.003 〇〇0.003 0.003 Plh 0.015 0.015 C 1.48 1.36 0.3ο 0.35 0.33 U 0.14 0.13 Plate thickness mm wn CsJ 〇 Grade SN-490C SN-490C Steel plate No stomach H oa (Please read the precautions on the back before filling this page)

HI i · I I, one \ " J φψ This paper size is applicable to China National Standard (CNS) A4 specification (210X297 mm) -35- 574380 A7 B7 V. Description of the invention? 3 Ministry of Economic Affairs, Intellectual Property / i Bureau, Consumer Cooperative Cooperative Production Test Board Thickness 25mm, Plate Thickness 40mm, Welding Condition Input Heat kJ / cm cn τ—Η ο Welding Speed cm / min oon CO oo CSI Backward Voltage V Current A 1150 1400 Steel wire diameter mm s Leading pole voltage V CO current A 1500 1800 Steel wire diameter mm 2 2 Welding conditions cd (Please read the precautions on the back before filling out this page) Order • f This paper size applies to Chinese National Standard (CNS) A4 Specifications (210X29 * / mm) 36 574380

A B V. Explanation of invention? 4) Examination of the preparation of the seal of the consumer cooperative of the employee of the Intellectual Property Bureau of the Ministry of Economic Affairs of the present invention. The present invention. The present invention. The present invention. The comparative example. The comparative example. The comparative example. The comparative example. -H 1 1 vrj 1 1 1 1 1 1 1 1 m 1 1 1 0.0010 .1 1 1 1! 1 1 g 1 1 1 1 0.080 1 1 1 1 1 1 ο s 1 1 0.50 0.20 1 1 1 1 1 1 1 1 Ti / N VO VO CNl CO CO VO 21 ΓΗ VO 2 0.0022 0.0032 0.0020 0.0024 0.0025 0.0040 0.0030 0.0030 0.0031 0.0024 0.0025 0.001 • 0.00 00 0.080 0.030 0.080 0.040 0.050 0.050 0.020 0.040 0.22 0,40! 0.040 GO 0.005 0.006 0.005 1 0.003 0.002 0.003 0.003 0.003 0.003 1 0.003 0.004 Plh 0.009 0.015 0.010 0.009 0.008 0.016 0.016 I 0.015 0.015 0.012 0.010 as 1.80 2.20 1.50 1.20 2.40 1.90 1.80 1.80 1.80 0.80 1 1.90 $ 0.05 0.35 0.30 0.03 0.02 0.01 0.30 0.20 0.20 0.02 0.50 u 0.06 0.04 0.05 0.08 0.07 0.06 0.06 0.06 0.07 0.07 1 0.06 0.08 Steel wire No < PQ u Q m Ph Ο Κ-Η I ------------ ^ --- IT ----- (Please read the precautions on the back first (Fill in this page again) National Standards (CNS) A4 size (210X297 mm) -37- 574380 A7 B7 V. invention will be described? 5) Printed chemical composition (mass%) of the consumer cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs of the Ministry of Economic Affairs, metal powder other than iron powder, VO iron powder, B2O3 inch 〇CaF2 inch Ti〇2 AI2O3 OO CaC〇3 ON Mg〇S1O2 flux ^ 0 ( (Please read the notes on the back before filling out this page)

This paper size applies to Chinese National Standard (CNS) A4 specification (210X297 mm) -38 574380 A7 B7 5. Description of the invention? 6) Printed by the Consumers' Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs, printed a LO test. Inventive Example i Inventive Example Inventive Example Inventive Example Inventive Example Comparative Example Comparative Example Comparative Example Comparative Example Comparative Example Tensile Strength TS (MPa ) ON 〇〇VO CN CNI CO csl VO VO ON OO oo VO o 5 OO OO § Resilience ο α CO oo CO VO t—H csi VO ii B > w ΙΟ rH 5S ON C < l CO csi v〇 (N1 csi CNl Welding combination welding conditions a X) Two c ^ i 〇3 c3 X) JD Flux No ρί Steel wire No. < PQ UQ Ol Kl Η- (I ►— > 1 Steel No. r—Η C < l Csi rH t—H r—H cvl C < | 4 CM Fusion Splice No CNl CO Inch oo ON 〇Γ " < (Please read the precautions on the back before filling this page)

This paper size applies to the Chinese National Standard (CNS) A4 specification (210X297 mm) -39- 574380 5. Explanation of the invention? 7)

AB Intellectual Property Bureau, Ministry of Economic Affairs, Employees, Consumer Cooperatives, Printing, Preparation, Examination, Invention Example, Invention Example, Invention Example, Invention Example, Comparative Example, Comparative Example, Comparative Example, Comparative Example, ^ 骊 鹧 骊 鹧 骊 鹧 § _ 13.1 r " H rH 〇〇CN 〇6 σ < 18.7 17.5 16.8 15.2 23.1 28.3 1 Έ Μ ^ 1 0.55 0.51 0.71 0.81 0.60 0.40 0.47 0.49 0.52 0.52 I 0.53 pq 0.0017 0.0020 0.0022 0.0026 0.0018 0.0016 0.0017 0.0019 0.0017 0.0017 π 0.0018 • 1 -* 1 1 0.19 1 1 1 1 1 1 1 I g 0.002 0.003 0.003 0.003 0.034 0.002 0.002 0.004 0.002 0.002 I 0.003 ο S 1 1 0.20 0.09 1 1 1 1 1 1 I 2 0.0031 0.0039 0.0031 0.0032 0.0030 0.0040 1 0.0036 0.0039 0.0033 0.0033 | 1 0.0033 0.0034 0.030 0.024 1 1 0.005 0.025 0.013 0.010 0.004 0.008 0.071 0.011 0.007 as 1.46 1.56 1.38 1.33 1.77 1.52 1.44 1.39 1 1.46 | 1.06 0.31 0.42 0.39 0.33 0.30 0.28 0.40 I 0.35 0.36 0.30 0.52 u 0.10 0.09 1--0.09 0 0.10 0.10 0.10 0.11 rH Ο 0.10 0.10 Welded joint No " 丨 Η CM CO Inch VO ν〇 卜 〇〇ON ο, please ( (Read the notes on the back before filling out this page)

This paper size applies to China National Standard (CNS) A4 specification (210X297 mm) -40- 574380 A7 B7 V. Description of the invention? 8) Chemical composition (mass%) printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs > 0.030 0.002 i 0.021 0.026 0.0040 0.0032 g 0.008 0.010 0.003 0.006 〇〇0.003 0.002 cu 0.015 0.011 c: 1.36 1.45 0.33 0.26 0.13 0.13 plate thickness mm O § Grade SN-490C TMCP steel plate No CO inch (please read the precautions on the back before filling this page), 11 ί This paper size applies the Chinese National Standard (CNS) Α4 specification (210'〆297 mm) -41 -574380 A7 B7 5. Explanation of the invention? 9) Printed by the Intellectual Property Bureau of the Ministry of Economic Affairs, 3 Industrial Cooperative Cooperatives, 00 skating cold ε e O tt chasing ε ε S 1 ¾ vertical _ donkey ε ON VD oa Ον uo mm Avoiding C C Β ε ο oo csl ON m it 铿 mi KM Tf o inch H Ο oo r—Η wrapped around I Xinjiang ss circle it Iff ^ oo CO punishment < flap ^ o oo t—H o CO < N Lti c wrapped _ m 2 s knot: u T3 ------------ ^ --- 1T ------ (Please read the precautions on the back before filling out this page) This paper size applies to China National Standard (CNS) A4 specifications (210X297 mm) -42- 574380 A7 B7 V. Description of the invention f〇) The production and examination of the consumer cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs, the preparation of the chemical examples of this invention (quality ㈣ • — 1 PQ 1 g * 〇1 Ti / N. v〇Csl 2 0.0032 0.079 GO 0.005 Ph 0.012 C s 2.08 0.33 u 0.05 Steel wire (Please read the precautions on the back before filling this page)

This paper size applies the Chinese National Standard (CNS) A4 specification (210X 297 mm) -43- 574380 A7 B7 V. Description of the invention f1) Chemical composition (mass%) printed by the Intellectual Property Bureau of the Ministry of Economic Affairs, 8th Industrial Cooperative, except for iron powder Of metal powder CO iron powder * CO CN CO CN CO (N CO CO v〇a Β2〇3 CO XT VO c > cn CaF2 inch inch inch cn v〇Ti〇2 VO VD VO m ah Ah 03 oo bl r- Inch r- CaCCh oo 〇o On Mg〇wo C < 1 VO S1O2 On ON ON Solder FL-2 FL-3 FL-4 FL-5 FL-6 FL-7 (Please read the precautions on the back before filling this page )

This paper size applies Chinese National Standard (CNS) A4 specification (210 × 297 mm) -44- 574380 A7 B7 V. Description of invention f2) Table 1 1 Iron powder N 〇 · N content (% by mass) a 0.0 0 2 0 β 0.0 0 2 8 r 0.0 0 4 5 (Please read the notes on the back before filling out this page), π MW0! The paper printed by the Consumers' Cooperatives of the Intellectual Property Bureau of the Ministry of Economy applies the Chinese National Standard (CNS) Α4 specifications ( 210X297 mm) -45- 574380 A7 B7 V. Description of Invention f3) Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs

srH Note! Inventive Examples Inventive Examples Inventive Examples Inventive Examples Inventive Examples Intensity TS (MPa) Inch ON g ON ON VO CN Toughness VE-20 (J) < N 〇〇g OO C < l > sr ^ H oo oo ON Welding combination welding conditions 0o T3 T3 TD o Flux No ί FL-2 FL-3 FL-4 FL-5 FL-6 Ί FL-7 j Steel wire No. Hl J Steel No. CO CO inch inch CO welded joint No cs oa C < l CO csi < N CN v〇CN

Order (Please read the notes on the back before filling this page)

This paper size applies to China National Standard (CNS) A4 (210X297 mm) -46- 574380

A B V. Description of invention f) Printed by the Consumer Cooperatives of the 1st Bureau of Smart Finance, Ministry of Economic Affairs

Remarks I_ Example of the invention Example of the invention Example of the invention Example of the invention Example of the invention_ Protect _ 鹧 领 女 g 锄 留 ιΐή CNj αν s wn ON 14.7 Ren · and Έ 1 1 ^ 1 0.78 1.04 0.65 0.61 0.60 0.52 PQ 0.0018 0.0025 0.0020 0.0022 0.0027 0.0015 1 I 1 1 0.05 _1 1 g 0.004 0.004 0.005 0.011 0.005 0.004 ο s 0.25 0.26 0.12 1 1 1 2 0.0023 0.0024 0.0031 0.0036 0.0045 _1 0.0029 • — 0.018 0.020 0.021 0.023 0.021 0.019 as 1.44 1.48 1.53 1.50 1.47 * c75 0.46 1 .. 0.45 0.39 0.38 0.41 I 0.48 u (0.09 1 0.09 0.10 0.09 0.10 0.09 Weld joint No οα 04 cn cs VO CN (Please read the precautions on the back before filling this page)

• mun · mn,? T 0Ψ. This paper size is applicable to the Chinese National Standard (CNS) A4 (210X297 mm) -47- 574380 A7 B7 V. Description of the Invention f5) The Intellectual Property Bureau, Ministry of Economic Affairs, the Consumer Cooperatives printed and prepared the test board 40mm thickness 60mm thickness Welding conditions | Input heat kJ / cm On v〇04 H CN Welding speed cm / min oo CSI Backward voltage V Current A 1400 1800 Steel wire diameter mm 2 2 Forward voltage V oo CO Current A 1800 2300 Steel wire diameter mm S s Welding conditions 〇2 (Please read the precautions on the back before filling this page) The size of the paper is applicable to the Chinese National Standard (CNS) A4 specification (210X297 mm) -48- 574380 A7 B7 V. Description of the invention f6) Printed ίi Chemical composition (mass%) g 1 0.0040 • — 1 0.004 as 2.11 0.35 u 0.04 Steel wire ----: --- Order --- --_ (Please read the notes on the back before filling out this page) This paper size is applicable to China National Standard (CNS) A4 specification (210X297 mm) -49- 574380

AB 5. Strict description of the invention) Printed by the Intellectual Property Bureau of the Ministry of Economic Affairs 8 Printed by Industrial Cooperatives 9 I General 1 Comparative Example Inventive Example Inventive Example Comparative Example Inventive Example Inventive Example Inventive Example Inventive Example Inventive Example Inventive Example Comparative Example Comparative Example Inventive Example Inventive Example Chemical composition (mass%) Nb * Kind: Content 1 1 1 1 Fe-Nb: 0.1 1 1 Fe-Nb: 0.1 Fe-Nb: 0.05 Nb powder: 0.05 Nb powder j0 .05 1 1 Fe-Nb: 0.12 Mo * Species: Content 1 1 1 1 Mo powder: 1.0 Mol powder: 1.5 5 Fe-Mo: 0.6 Fe-Mo: 0.6 Fe-Mo: 0.6 Fe-Mo : 0.6 1 Fe-Mo: 1.5 1 g * * 氺 Type: Content B2〇3: 0.03 Β2〇3: 0 · 05 Β2〇3: 0 · 05 B2〇3: 0.05 Β2〇3: 0.08 I Β2〇3 : 0 · 11 Β2〇3: 0 · 06 B2〇3: 0.06 Β2〇3: 0 · 06 Β2〇3: 0 · 06 Β2〇3: 0 · 06 1 1 | f XH JjTE ul 衾 站 m wo > r ^ CO CO CO CO Fierce iron: 3 Ferromanganese: 3 cn CO Inch_ mmm ϋ 鲡 鲡 Fiber M m Type of iron powder: Content CO! '" H ώ Isolate · ul Free Royalty Free Free ο < ο PQ s PQ CN CN c3 inch inch inch inch inch inch inch CO CO CO CO CO CO CO j ^ r * H VO v〇ν〇vo ο wo inch inch CO ON ON _ i oo r-寸 inch νο νο wn inch m wn CaC〇3 or—i 〇1 i 〇 r—Η 〇σ \ ON ON GN oo oo oo vo CN i—H csi t—H CN cn Csl different different two r- two vo 1 '< ϊ〇νϊ oa ττ-Η VO ^ -Η οα τ-Η < N r-H οα 1 i t-4 螋 蘅 z cs CO (X · 2 VO PU οο 〇csi CO E inch El: _ ^ < ΓΠ ^ κ- «戴 螩 ^ 你 (* ------------ ^ --- 1Τ ----- I (Please read the notes on the back before filling in (This page) This paper size is in accordance with Chinese National Standard (CNS) A4 specification (210X297 mm) -50- 574380 A7 B7 V. Description of the invention f8) Table 1 7 Atomized iron powder N 〇 N content (% by mass) A 0.0019 B 0.0 0 2 7 C 0.0 0 4 0 Printed by the 8th Industrial Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs (please read the precautions on the back before filling this page)

This paper size applies the Chinese National Standard (CNS) A4 specification (210X297 mm) -51-574380 A7 B7 V. Description of the invention f9) Printed by the Intellectual Property Bureau of the Ministry of Economic Affairs, S Industrial Consumer Cooperative, 001 Preparation of Comparative Examples, Examples of the Invention, Examples of the Invention Examples Comparative Examples Inventive Examples Inventive Examples Inventive Examples Inventive Examples Inventive Examples Inventive Examples Comparative Examples Comparative Examples Inventive Examples Inventive Examples Weld Beads Poor Appearance Good ^ ν $ t Good tensile strength TS (MPa) 〇〇ON un CO § s Ο] Η VO… s un g \ o VO VO un oo oo CO… ON U0 VD toughness is heart CN 1 '1 iv〇CO CO (N CO VO oo CN) oo C < l ON r—H ON Csl OO CN Welding Combination Welding Conditions < υ < υ (D < υ < υ < + · Η ^ +-4 Flux No d CO 21 Ph VO A oo Ph On | X | ο r—Η r—H rH Uh CO 1—H | X | CO r—H (Xl inch rH tin steel No. S s steel No. CO CO CO cn CO Inch fusion splice No 1 CO csi 1 cn CO cA CO cA VO 1 CO rp CO oo 1 CO On CO 〇 \ 4 cA rH t— < 1 CO CM H 1 CO cn < < 1 CO inch cn I___: ___________ T ----- (Please read the precautions on the back before filling this page) This paper size applies the Chinese National Standard (CNS) A4 specification (210X297 Mm) -52- 574380

A B7 V. Description of the invention) Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs

Remarks Comparative Examples Inventive Examples Inventive Examples Inventive Examples Inventive Examples Inventive Examples Inventive Examples Inventive Examples Inventive Examples Inventive Examples Comparative Inventive Examples Inventive Examples Inventive Examples S ^ _Love Reserved_ 16.3 10.0 12.7 17.2 cs ON 14.5 14.7 10.4 26.8 25.0 13.4 14.2 Έ Μ ^ 1 0.41 0.55 0.52 0.45 0.61 1 1.17 0.57 0.62 0.60 0.43 0.45 1 1 PQ 0.0009 0.0012 0.0012 0.0014 0.0019 1 0.0034 0.0017 0.0018 0.0021 0.0020 0.0019 1 1 • 1 —4 1 Exposure 1 1 1 I 1 1 1 1 1 1 1 1 g 0.004 0.003 0.004 0.004 0.019 0.003 0.004 0.018 0.011 0.012 0.011 0.006 0.005 0.020 〇1 1 1 1 1 0.28 0.48 1 0.19 0.20 0.18 0.17 1 0.49 1 2 0.0022 0.0022 0.0023 0.0031 0.0031 0.0033 0.0029 0.0030 0.0029 0.0035 0.0046 0.0042 0.0026 0.0027 • — 0.004 0.004 0.005 0.004 0.004 0.004 0.005 0.004 0.005 0.006 0.005 0.005 0.006 0.005 a S 1.29 CO f 1 — 1.56 1.62 1.32 CN CO ....... 4 1.33 1.77 1.64 1.76 1.59 1.34 1.30 0.47 0.49 0.30 0.31 0.39 0.41 0.40 0.32 0.30 0.31 0.29 0.31 0.44 -1 0.43 U 0.09 0.09 0.10 0.09 0.09 0 .10 0.09 0.09 0.09 0.10 0.10 0.09 0.09 0.10 Weld joint No < N 1 CO CO cA cn un 1 CO v〇1 CO cA oo cn αν cA 3-10 1 i I 1 Η I cn 3-12 3-13 inch rH cA (please read the precautions on the back before filling this page), 1-portion. This paper size is applicable to China National Standard (CNS) A4 (210X297 mm) -53-

Claims (1)

574380—— I: ί * Λ .Λ,: Ί: Γ / b- ~ 1 ___— Γ VI. Application for Patent Scope No. 901 23390 Patent Application Chinese Patent Amendment (Please read the notes on the back before filling in (This page) Amended on August 6, 1991 1. A submerged arc welding joint is mainly used for submerged arc welding joints with a high heat input of more than 150 k J / cm in the thermal system. The weld metal component contains C: 0.03 to 0.15%, Si: 〇.ΐ〇 to i.oo%, Μη: 0. 70 to 2.50%, Ti: 0.003 to 0.0 3 0% by mass%, N: 0 · 0050% or less and the amount of grain boundary ferrous iron in the above-mentioned welded metal is 15.0% by area or less is a feature of it 2 · The submerged arc welded joint described in item 1 of the patent application scope, wherein The above-mentioned weld metal further contains, by mass%, Mo: 〇. 1 〇 ~ 0.50%, Nb: 0.010 ~ 0.200%, printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs: 0 · 0 5 ~ 1 · 0 0 One or two or more selected in%, and 60 · 60SB / NS1. 20 and the grain boundary in the above-mentioned welded metal. The amount can satisfy 10% or less area%. 3. — A manufacturing method of submerged arc welding joints, which is mainly used in the manufacturing method of submerged arc welding joints welded by submerged arc welding with a high heat input of more than 150 kJ / cm and a high heat input. Its characteristics are as follows: The welding metal of the above welding joint is contained in mass%, C: 0.03 to 0.15%, Si: 0.1 to 1.0%, Mn: 0.7 to 2.50%, Ti : 0.003 ～ This paper size is applicable to China National Standard (CNS) A4 specification (210 X 297 mm): 574380 A8 B8 C8 D8 VI. Patent application scope 0 · 030%, N: 0 · 0050% and below the weld metal The amount of iron produced in the middle grain boundary is less than 15.0 area%. (Please read the precautions on the back before filling this page) 4 · The manufacturing method of the submerged arc welding joint described in item 3 of the scope of patent application, in which the above welding metal contains one or two reasons by mass% Μο: 〇.1 ◦ to 0.50%, Nb: 0.010 to 〇.200%, Ni: 0.05 to 1.00% or more, and 0. 60 $ B / N € 1.20, and the amount of grain boundary fat and granules produced in the above-mentioned welded metal can satisfy the area of less than 10.0% by area. 5 types of submerged arc fusion spun steel wires with high heat input, including: Contained by mass%: C: 0.03 ~ 0.10%, N: 0.0035% or less, Si: 0.40% or less, Mη: 1 · ◦0 ~ 2. 50%, and then it is composed of steel wire which can satisfy Ti: 0.30% or more, and T i / N: 1 5 ~ 50, the remaining part Fe and unavoidable impurities As its characteristics. Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs 6. The steel wire for submerged arc welding with high heat input as described in item 5 of the scope of the patent application, which is included in the above steel wire composition and is expressed in mass%. Μο: 〇 · １〇 ～ 0.60%, Nb: 0.010 ~ 0 · 100%, Β: 〇 · 〇〇〇〇5 ~ 0.0100%, Ni: 0.20 ~ 2_ 0 0% selected one or two or more . 7 · — A method for manufacturing a submerged arc welding joint with excellent toughness of the welded metal part, mainly by submerged arc welding with high heat input above 150 k J / cm Arc Welding Joints This paper is sized for the Chinese National Standard (CNS) A4 (210X297 mm) " " " -2-574380 A8 B8 C8 D8 6. In the manufacturing method for patent application, its characteristics are: (Please Read the precautions on the back before filling in this page) Steels with a content of less than 0.006% by mass and ^] 3 containing a base material with a content of 0 · 0 1 2% by mass or less will be used. %: C: 〇 · 〇3 ~ 0. 10%, N: 〇 · 〇〇35% or less, Si: 〇 · 40% or less, Mn: 1 · 〇〇 ~ 2.50%, and can Satisfying T.i: 〇.030% or more, and Ti / N: 15-50%, the remaining Fe and the composition of unavoidable impurities, submerged arc welding with high heat input is made of steel wire Characteristic welding. 8 · The manufacturing method of the submerged arc welding joint as described in item 7 of the scope of the patent application, wherein the composition of the steel wire is further contained, and the mass% is 〇: 〇 · 10 ~ 0.60%, Nb: 0.010 ~ 〇 · 100%, B: 0.005 ~ 0.0100%, Ni: 0.20 ~ 2. 00%, one or more steel wires for submerged arc welding with high heat input. Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs9. The manufacturing method of submerged arc welding joints described in item 7 or 8 of the scope of patent application, wherein the welding flux used in the above-mentioned high-temperature submerged arc welding contains Boron oxide welding flux. 10 · The manufacturing method of the submerged arc welding joint described in item 9 of the scope of the patent application, wherein the welding flux used for the submerged arc welding with high heat input mentioned above is 8% by mass or less of alloy powder containing iron powder By. 1 1 · The method for manufacturing a submerged arc welding joint as described in item 10 of the scope of the patent application, wherein the above welding flux contains 20 to 45% of iron powder in mass% and containing N: 0. 〇30% or less By. This paper is applicable to Chinese National Standard (CNS) Eighty-fourth Secret (21〇 > < 297 公 幻 -3- 574380 A8 B8 C8 D8 _ VI. Scope of patent application (please read the precautions on the back before filling this page) 1 2 · A flux for submerged arc welding, characterized in that the total amount of the flux contains 20 to 45% by mass of the N atomized iron powder having a content of 0.030% by mass or less. 1 3 · The submerged arc welding flux as described in item 12 of the scope of the patent application, wherein the flux further contains a B compound, and in terms of B, the flux is contained in an amount of 0.3 to 0.3 mass%. 14. The flux for submerged arc welding according to item 12 or item 13 of the scope of the patent application, wherein the flux further contains (A) group: M o powder, molybdenum iron powder, and mo compound powder. One or two or more of the total amount of the flux in terms of M 0, totaling 0.2 to 2.0 mass%, (B) group: one or two or more of Nb powder, ferroniobium powder, and Nb compound powder One or two groups selected from the total amount of N b and total flux of 0.0 2 to 0 · 15% by mass 5. The submerged arc welding flux as described in item 12 or 13 of the scope of patent application, wherein the above flux is contained in the entire amount of the flux, and the content is SiO2: 10 ~ 28%, CaC〇3: 5 to 15%, Mg 〇: 15 to 38%, A 1 2 0 3: 3 to 20%, printed by the Consumers' Cooperative of Intellectual Property Bureau of the Ministry of Economic Affairs, and 2 ~ 10%, C a F 2: 2 ~: L 0%, atomized iron powder, M ◦ powder, iron molybdenum powder, N b powder, and metal powder other than ferroniobium powder: one or two selected from 2 to 8% The above: 16. The flux for submerged arc welding as described in item 12 or item 13 of the scope of patent application, wherein the above flux further contains: (A) group: Μ powder, molybdenum iron powder, and Μ 〇 One or two or more of the compound powders are converted to Μ 〇 to total the total amount of flux, and 0 · 2 ~ 2 · 0 mass%, (Β) the paper size applies the Chinese National Standard (CNS) A4 specification (210X297 mm) ） &Quot; ： " 574380 A8 B8 C8 D8 6. Scope of patent application (please read the notes on the back before filling this page) Group: N b powder, ferroniobium powder and N b compound powder One or two or more of them are converted into N b in total and contained 0. 0 2 to 0. 15% by mass for the total amount of the flux. One or two or more are selected and the total amount of the flux is contained in Mass%: S i〇2: 10 to 28%, CaC03: 5 to 15%, Mg0: 15 to 38%, Al203: 3 to 20%, Ti〇2: 2 to 10 %, C a F 2: 2 ~ 10%, atomized iron powder, MO powder, molybdenum iron powder, Nb powder and metal powder other than ferroniobium powder: one or two selected from 2 to 8% The above. 17. — A method for manufacturing a submerged arc welding joint with excellent toughness of the welded metal part, mainly by submerged arc welding with a high heat input of more than 150 k J / cm and a fusion input. In the manufacturing method of Chengzhi submerged arc welding joint, it is characterized by: printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs with Ti content of 0.006 mass% or less, and Nb content of 0 · 0 1 2 mass% or less The base steel is composed of a steel material, and the content of N is: for the total amount of flux: 0. 〇3 0% by weight of atomized iron powder and 20% to 45% by weight of the flux composition Flux to weld. 1 8 · The method for manufacturing a submerged arc welding joint as described in item 17 of the scope of the patent application, wherein the flux composition described above further contains 0.003 ~ 0 · 30 mass compounds in terms of the total amount of the flux in terms of B. 〇1 9 · The manufacturing method of submerged arc welding joints as described in item 17 or item 18 of the scope of patent application, wherein the flux composition mentioned above further contains (A) This paper size is applicable to China National Standard (CNS) A4 specifications ( 210X297 mm) 574380 A8 B8 C8 _08 VI. Patent application group: one or two of 〇 powder, molybdenum iron powder and μ 〇 compound, converted to Μ 〇 and total for the total amount of flux and 0.2 ~ 2 · 〇 Mass%, (Please read the precautions on the back before filling this page) (B) Group: One or more of NB powder, niobium rhenium powder, and ν b compound, converted to N b for the total flux. 〇 · 〇2 ~ 〇 · 15% of the selected one or more groups. 20 · The method for manufacturing a submerged arc welding joint as described in item 17 or item 18 of the scope of the patent application, wherein the flux composition described above further comprises S i 2: 1 〇 ~ 28%, CaC〇3: 5 ~ 15%, Mg〇: 15 ~ 38%, Α12〇3 ·· 3 ~ 20%, Ti〇2: 2 ~ 10%, C a F 2: 2 ~ 10% , Atomized iron powder, MO powder, molybdenum iron powder, N b powder and metal powder other than ferroniobium powder: one or two or more selected from 2 to 8%. 2 1 · The method for manufacturing a submerged arc welding joint as described in item 17 or item 18 of the scope of the patent application, wherein the flux composition further contains: (A) group: M o powder, molybdenum iron powder, and mo compound One or two or more of them, converted into M 0, totaling the total amount of solder and 0.2 to 2.0% by mass. Printed by the Consumer Cooperative of the Intellectual Property Bureau of the Ministry of Economic Affairs, (B) group: N b powder, ferroniobium powder or One or two or more of the N b compounds are converted into N b in total and the total amount of the flux is 0.02 to 0.15%, of which one or two or more groups are selected, and the mass of the flux is contained in mass. % Si 2: 1 0 to 2 8%, CaC0 3: 5 to 15%, Mg 0: 15 to 38%, A 1 2 0 3: 3 to 20%, Ti 2: 2 to 10 %; C a F 2: 2 ~ 10%, atomized iron powder, Μ〇 powder, molybdenum iron powder, N b powder or molybdenum paper travel standard applicable to China National Standard (CNS) A4 specification (210X297 mm) " : "一 ^ 574380 A8 B8 C8 D8", one or two or more selected from 28% of metal powders outside the scope of patent application (please read the precautions on the back first) Refill this page) Printed by the Consumer Cooperatives of the Intellectual Property Bureau of the Ministry of Economic Affairs This paper size applies to China National Standard (CNS) A4 (210X297 mm)