Protection nozzle for double-protection welding gun and production process of protection nozzle

Abstract

The invention discloses a protection nozzle for a double-protection welding gun and a production process thereof, the protection nozzle comprises a cylindrical protection tube, the protection tube is made of graphite, and the inner wall of one end of the protection tube is provided with threads. The protective nozzle has the following advantages and effects that graphite is adopted as a main material to manufacture the protective nozzle of the double-shielded welding gun, the melting point of the graphite is about 3800 DEG C and is far higher than 2500 DEG C of a double-shielded welding pool, and therefore the problem that the protective nozzle is prone to being burnt out is solved. As the graphite has the characteristics of high melting point and surface pulverization at about 1000 DEG C, the adhesion between the graphite and high-temperature molten iron splashes is reduced, and a small amount of slag is very easy to clean, so that the effects of difficulty in slag bonding and easiness in slag cleaning are achieved, and the frequency and time of replacing and cleaning the protective nozzle in the welding production process of carbon dioxide arc welding are greatly reduced. The service life of the protective nozzle is greatly prolonged by adopting the graphite material, and the protective nozzle plays a positive role in saving the cost and improving the efficiency in the welding production process.

Description

Technical Field

[0001] The invention relates to the field of welding equipment, in particular to a protective nozzle for a double-shielded welding gun and a production process thereof. Background Art

[0002] At present, the double welding machine is the most widely used welding process in the domestic welding field. It plays an important role in the machinery manufacturing industry, construction industry, shipbuilding industry, energy and aerospace industry.

[0003] The shield of the welding gun is the part that is in the closest contact with the welding pool during welding, and it is also a vulnerable part. At present, the shields of copper and brass are the main materials in China, and there are also very few manufacturers that use aluminum alloy and ceramic materials to manufacture shields of welding guns.

[0004] However, the protective nozzle of the two-shield welding gun is mostly made of brass and copper, which have a melting point of about 1000℃. During the welding process, it is the part that is closest to the welding pool. Since the temperature of the welding pool is about 1700-2500℃, it is very easy to burn the protective nozzle. The melting point of aluminum alloy is about 660℃, which is more prone to damage and slag. Ceramic materials are prone to cracking and slag when encountering high-temperature molten iron splashes.

[0005] In addition, the high-temperature molten iron splashes during the welding process will directly stick to the shield mouth and clog the shield mouth in a short time. Since the shield mouth is made of metal and is easily adhered to the high-temperature molten iron splashes and is difficult to clean, during the welding production process, the operator needs to clean it frequently or even frequently replace the dioxide welding gun shield mouth, resulting in waste of manpower and loss of production efficiency. Summary of the invention

[0006] In view of the shortcomings of the prior art, the purpose of the present invention is to provide a protective nozzle for a double-shielded welding gun, which has the effect of improving production efficiency.

[0007] The above technical purpose of the present invention is achieved through the following technical solutions: a protective nozzle for a double-shielded welding gun, comprising a protective tube arranged in a cylindrical or polygonal shape, the protective tube is made of graphite, and the inner wall of one end thereof has a thread.

[0008] In a preferred example, the present invention can be further configured as follows: the inner diameter of the thread is less than or equal to the diameter of the protective tube.

[0009] In a preferred example, the present invention may be further configured as follows: an arc chamfer is provided at one end of the protection tube away from the screw thread.

[0010] In a preferred example, the present invention can be further configured as follows: the arc chamfer includes an inner chamfer and an outer chamfer, and the inner chamfer and the outer chamfer extend from the middle position of the protective tube to both sides, so that the cross-section of the end position of the protective tube is set in a semicircular shape.

[0011] In a preferred example, the present invention can be further configured as follows: the outer wall of the protection tube is sheathed with a metal tube.

[0012] In a preferred example, the present invention can be further configured as follows: a supporting skeleton is arranged inside the protective tube, the supporting skeleton includes an outer skeleton and an inner skeleton, the outer skeleton includes a pair of outer rings and a plurality of outer ribs, the plurality of outer ribs are spirally arranged between the pair of outer rings, the inner skeleton includes a pair of inner rings and a plurality of inner ribs, the plurality of inner ribs are spirally arranged between the pair of inner rings, the spiral directions of the outer ribs and the inner ribs are opposite, and a card groove for the inner ring to be snapped and embedded is provided on the inner side of the outer ring.

[0013] In a preferred example, the present invention can be further configured as follows: the outer wall of the protection tube (1) is provided with a grid groove, and a protective net is embedded in the grid groove.

[0014] Another object of the present invention is to provide a production process for a protective nozzle for a double-shielded welding gun, which has the effect of convenient production and processing.

[0015] The above technical objectives of the present invention are achieved through the following technical solutions: A production process of a protective nozzle for a double-shielded welding gun, comprising the following steps: S1, raw material selection, high purity and high crystallinity petroleum coke and asphalt coke are selected as the main raw materials, and coal tar is selected as the binder; S2, raw material pretreatment, first crushing and screening the raw materials to remove particles that do not meet the particle size requirements, and then removing impurities, water and magnetization from the raw materials; S3, batching and mixing, according to production requirements, the raw materials of different particle sizes are fully mixed in proportion, and after mixing, an appropriate amount of binder is added, and the mixture is fully stirred and mixed again, and the raw materials and the binder are evenly distributed; S4, forming, through vibration forming, extrusion forming, compression molding and isostatic pressing, the mixed raw materials are formed into a blank with a certain shape and size, and the blank is in the shape of a plate, block or rod; S5, calcining, placing the green body in a calcining furnace, in an airtight condition or in an environment where an inert protective gas is continuously introduced, heating to 800-1000°C, so that the binder undergoes pyrolysis and polycondensation reaction to form a coke network, thereby giving the green body a certain mechanical strength; S6, graphitization, placing the calcined green body into a graphitization furnace and heating it to 2300-3000°C to transform the carbon atoms from a turbostratic structure to a graphite crystal structure; S7, making blanks, selecting blanks with a density greater than 1.0g / cm³, which can be sawed into graphite sheets of suitable thickness by wire sawing or hacksaw, etc., the graphite sheets can be drilled into cylindrical blanks by multi-head hollow drills for standby use, and the graphite sheets can also be processed into cylindrical blanks by wire sawing or lathe turning; S8, finishing, clamping the graphite cylindrical blank onto the machine tool, and obtaining the finished protective nozzle through the processes of hole opening, tapping, and chamfering; S9, outer layer reinforcement, cut the short metal tube, and then press the finished protective nozzle into the metal tube, use interference fit to fix the two, or process a grid groove on the outer wall of the protective nozzle, and then embed the protective net in the grid groove.

[0016] In a preferred example, the present invention can be further configured as follows: in step S5, the calcined green body can be impregnated, that is, the internal pores thereof are filled with asphalt or other fillers, and then heated to 800-1000°C for calcination again.

[0017] In a preferred example, the present invention can be further configured as follows: in step S8, the finished protective nozzle can be immersed in liquid high-temperature resistant glue and then dried, and then the finished protective nozzle can be placed in a roasting furnace and heated to about 800-1000°C to cause the high-temperature resistant glue to undergo thermal decomposition and condensation reaction, thereby giving the graphite protective nozzle mechanical strength.

[0018] In summary, the present invention has the following beneficial effects: 1. The shielding nozzle of the two-way welding gun is made of graphite as the main material. The melting point of graphite is about 3800℃, which is much higher than the molten pool of two-way welding of 2500℃, so the problem of the shielding nozzle being easily burned out is solved; 2. As graphite has a high melting point and has the characteristics of surface powdering at about 1000℃, it reduces the adhesion with high-temperature molten iron splashes. Even if there is a small amount of slag, it is very easy to clean, achieving the effect of not easy to slag and easy to clean slag, greatly reducing the number and time of replacing and cleaning the protection nozzle during the two-protection welding production process; 3. The use of graphite material greatly increases the service life of the protective nozzle, which plays a positive role in saving costs and improving efficiency in the welding production process; 4. A simple production process is adopted to achieve stable production and processing of high-strength two-protection welding gun shielding nozzles, ensuring the service life of the shielding nozzles, while achieving the effect of facilitating production and processing. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1It is a schematic diagram of the structure of Example 1 and Example 2; Figure 2 Schematic diagram of the internal structure of different types of protective nozzles in Example 1 and Example 2; Figure 3 is a schematic structural diagram of Example 3; Figure 4 is a schematic diagram of the support skeleton structure of Example 4; Figure 5 is a schematic diagram of the connection relationship of the support frame of Example 4; Figure 6 is a schematic structural diagram of Example 5; Figure 7 It is a schematic diagram of the connection relationship of Example 5.

[0020] Figure numerals: 1. protective tube; 2. screw thread; 3. arc chamfer; 31. inner chamfer; 32. outer chamfer; 4. metal tube; 5. support frame; 51. outer frame; 52. inner frame; 53. outer ring; 54. outer rib; 55. inner ring; 56. inner rib; 57. slot; 6. grid slot; 7. protective net. DETAILED DESCRIPTION

[0021] The present invention is further described in detail below in conjunction with the accompanying drawings.

[0022] Embodiment 1: like Figure 1 , Figure 2 As shown, a protective nozzle for a two-protection welding gun includes a protective tube 1 arranged in a cylindrical or polygonal shape, the protective tube 1 is made of graphite, and the inner wall of one end thereof has a screw thread 2 for connecting to the two-protection welding gun body. In the actual production process, the screw thread 2 may not be provided, and an interference fit or a snap fit may be used to achieve the connection and fixation between the protective nozzle and the two-protection welding gun body.

[0023] By using graphite as the main material to make the two-way welding gun shield, the melting point of graphite is about 3800℃, which is much higher than the two-way welding molten pool of 2500℃, so the problem of the shield being extremely easy to burn out is solved. At the same time, due to the high melting point of graphite and the characteristics of surface powdering at about 1000℃, the adhesion with high-temperature molten iron splash is reduced, and even if there is a small amount of slag, it is very easy to clean, achieving the effect of not easy to slag and easy to clean slag, greatly reducing the number and time of replacing and cleaning the shield in the two-way welding production process. In addition, the use of graphite material greatly increases the service life of the shield, which plays a positive role in saving costs and improving efficiency in the welding production process.

[0024] like Figure 1 , Figure 2As shown, the inner diameter of the screw thread 2 is less than or equal to the diameter of the protection tube 1. When the protection nozzle is a small model, the inner diameter of the screw thread 2 is smaller than the diameter of the protection tube 1. When the protection nozzle is a large model, the inner diameter of the screw thread 2 is equal to the diameter of the protection tube 1, so as to facilitate the production and processing of the protection nozzle and ensure the structural strength of the protection nozzle. At the same time, whether the protection nozzle is a small model or a large model, the inner diameter of the screw thread 2 can also be selected to be larger than the diameter of the protection tube 1.

[0025] The conventional copper protective nozzle and the graphite protective nozzle of this embodiment were both operated for 240 hours, and the experimental data results are as follows: Copper Total cleanup 235 times Severe blockage 81 times Burnt out and replaced 28 The total cleaning and replacement time was 53 hours Graphite Total cleanup 59 times Severe blockage 0 times Burnt out and replaced 0 Cleaning takes 6 hours and no replacement is required because it will not be damaged Embodiment 2: like Figure 1 , Figure 2 As shown, an arc chamfer 3 is provided at one end of the protection tube 1 away from the screw thread 2 to prevent the head of the protection tube 1 from being damaged after being hit and to avoid stress concentration, thereby increasing the service life of the entire protection nozzle.

[0026] like Figure 1 , Figure 2 As shown, the arc chamfer 3 includes an inner chamfer 31 and an outer chamfer 32, and the inner chamfer 31 and the outer chamfer 32 extend from the middle position of the protection tube 1 to both sides, so that the cross section of the end position of the protection tube 1 is set in a semicircular shape.

[0027] Therefore, during the use of the protection tube 1, since the head position of the protection tube 1 adopts an inner and outer arc shape, when the splash contacts the head position of the protection tube 1, the contact surface is very small, so the adhesion with the high-temperature molten iron splash is reduced, and the probability of slagging is reduced, so that the splash automatically falls off after solidification, and even if there is a small amount of slag, it is very easy to clean, thereby achieving the effect of not easy to slag and easy to clean slag.

[0028] Embodiment 3: like Figure 3 As shown, the outer wall of the protection tube 1 is provided with a metal tube 4 to protect the protection tube 1 and prevent the protection nozzle from being damaged due to external impact or collision, so as to increase the service life of the entire protection nozzle.

[0029] Embodiment 4: like Figure 4 , Figure 5As shown, a support frame 5 is provided inside the protection tube 1, and the support frame 5 includes an outer frame 51 and an inner frame 52. The outer frame 51 includes a pair of outer rings 53 and a plurality of outer ribs 54, and the plurality of outer ribs 54 are spirally arranged between the pair of outer rings 53. The inner frame 52 includes a pair of inner rings 55 and a plurality of inner ribs 56, and the plurality of inner ribs 56 are spirally arranged between the pair of inner rings 55. The spiral directions of the outer ribs 54 and the inner ribs 56 are opposite, and a slot 57 for the inner ring 55 to be snapped and embedded is provided on the inner side of the outer ring 53.

[0030] By using the outer frame 51 and the inner frame 52 of opposite rotation direction, the structural strength of the entire support frame 5 is enhanced, thereby realizing the internal reinforcement of the protective mouthpiece, improving the structural strength of the entire protective mouthpiece, and extending the service life of the protective mouthpiece. At the same time, the outer frame 51 and the inner frame 52 are quickly connected by a clamping method, so that the support frame 5 can be quickly assembled and used.

[0031] Embodiment 5: like Figure 6 , Figure 7 As shown, the outer wall of the protection tube 1 is provided with a grid groove 6, and a protection net 7 is embedded in the grid groove 6. After the protection nozzle is produced, the staggered grid grooves 6 are processed on the outer wall of the protection tube 1, and then the metal protection net 7 is wrapped around the protection tube 1, and the protection net 7 is embedded in the grid groove 6, and finally the joint position of the protection net 7 is welded and fixed to realize the installation of the protection net 7, so as to improve the structural strength of the entire protection nozzle and extend the service life of the protection nozzle.

[0032] Alternatively, staggered grid grooves 6 may be machined on the outer wall of the protection tube 1, and then a circle of cement may be applied to the outer wall of the protection tube 1. After the cement solidifies, the cement automatically fills the grid grooves 6 and automatically forms a protective net 7 that wraps the protection tube 1, so as to improve the structural strength of the entire protection nozzle and extend the service life of the protection nozzle.

[0033] Embodiment 6: A production process of a protective nozzle for a double-shielded welding gun comprises the following steps: S1, raw material selection, high purity and high crystallinity petroleum coke and asphalt coke are selected as the main raw materials, and coal tar is selected as the binder.

[0034] S2, raw material pretreatment, first the raw materials are crushed and screened to remove particles that do not meet the particle size requirements, and then the raw materials are pretreated by removing impurities, water and magnetism.

[0035] S3, batching and mixing, according to production requirements, raw materials of different particle sizes are fully mixed in proportion, and after mixing, an appropriate amount of binder is added, and the mixture is fully stirred and mixed again to ensure that the raw materials and the binder are evenly distributed.

[0036] S4, forming, through vibration forming, extrusion forming, compression molding and isostatic pressing, the mixed raw materials are made into a blank with a certain shape and size, and the blank is made into a plate, block or rod shape.

[0037] S5, roasting, placing the green body in a roasting furnace, and heating it to 800-1000°C in an airtight condition or in an environment where an inert protective gas is continuously introduced, so that the binder undergoes thermal decomposition and polycondensation reaction to form a coke network, thereby giving the green body a certain mechanical strength.

[0038] S6, graphitization, placing the calcined green body into a graphitization furnace, heating it to 2300-3000°C, so that the carbon atoms are transformed from a chaotic layer structure to a graphite crystal structure.

[0039] S7, make blanks, select blanks with density greater than 1.0g / cm³, which can be sawed into graphite sheets of suitable thickness by wire saw or hacksaw. The graphite sheets can be drilled into cylindrical blanks by multi-head hollow drills for standby use. The graphite sheets can also be processed into cylindrical blanks by wire sawing or lathe turning.

[0040] S8, finishing, clamping the graphite cylindrical blank onto the machine tool, and obtaining the finished protective nozzle through the processes of hole opening, tapping and chamfering.

[0041] S9, outer layer reinforcement, cut the short metal tube, and then press the finished protective nozzle into the metal tube 4, use interference fit to fix the two, or process a grid groove 6 on the outer wall of the protective nozzle, and then embed the protective net 7 in the grid groove 6.

[0042] Embodiment 7: In step S5, the calcined green body may be impregnated, that is, the internal pores thereof may be filled with asphalt or other fillers, and then heated to 800-1000° C. for calcination again, so as to improve the density and mechanical strength of the green body.

[0043] Embodiment 8: In step S8, the finished protective nozzle can be immersed in liquid high temperature resistant glue and then dried, and then placed in a roasting furnace and heated to about 800-1000°C to cause thermal decomposition and polycondensation of the high temperature resistant glue, thereby giving the graphite protective nozzle super high density and mechanical strength.

[0044] The specific embodiments are merely explanations of the present invention and are not limitations of the present invention. After reading this specification, those skilled in the art may make modifications to the embodiments without any creative contribution as needed. However, such modifications are protected by the patent law as long as they are within the scope of the claims of the present invention.

Claims

1. A protective nozzle for a double-shielded welding gun, characterized in that: The protective tube (1) comprises a cylindrical or polygonal protective tube (1), the protective tube (1) is made of graphite and has a screw thread (2) on the inner wall of one end thereof.

2. The protective nozzle for a double-shielded welding gun according to claim 1, characterized in that: The inner diameter of the thread (2) is smaller than or equal to the diameter of the protective tube (1).

3. The protective nozzle for a double-shielded welding gun according to claim 1, characterized in that: An arc chamfer (3) is provided at one end of the protection tube (1) away from the screw thread (2).

4. The protective nozzle for a double-shielded welding gun according to claim 3, characterized in that: The circular chamfer (3) comprises an inner chamfer (31) and an outer chamfer (32), wherein the inner chamfer (31) and the outer chamfer (32) extend from the middle position of the protection tube (1) to both sides, so that the cross section at the end position of the protection tube (1) is arranged in a semicircular shape.

5. The protective nozzle for a double-shielded welding gun according to claim 1, characterized in that: The outer wall of the protection tube (1) is sleeved with a metal tube (4).

6. The protective nozzle for a double-shielded welding gun according to claim 1, characterized in that: A support frame (5) is arranged inside the protection tube (1), and the support frame (5) comprises an outer frame (51) and an inner frame (52). The outer frame (51) comprises a pair of outer rings (53) and a plurality of outer ribs (54), and the plurality of outer ribs (54) are arranged in a spiral shape between the pair of outer rings (53). The inner frame (52) comprises a pair of inner rings (55) and a plurality of inner ribs (56), and the plurality of inner ribs (56) are arranged in a spiral shape between the pair of inner rings (55). The spiral directions of the outer ribs (54) and the inner ribs (56) are opposite, and a slot (57) for the inner ring (55) to be snapped and embedded is arranged on the inner side of the outer ring (53).

7. The protective nozzle for a double-shielded welding gun according to claim 1, characterized in that: The outer wall of the protection tube (1) is provided with a grid groove (6), and a protection net (7) is embedded in the grid groove (6).

8. A production process for a protective nozzle for a double-shielded welding gun, used for producing the protective nozzle as claimed in any one of claims 1 to 7, characterized in that: The steps include: S1, raw material selection, high purity and high crystallinity petroleum coke and asphalt coke are selected as the main raw materials, and coal tar is selected as the binder; S2, raw material pretreatment, first crushing and screening the raw materials to remove particles that do not meet the particle size requirements, and then removing impurities, water and magnetization from the raw materials; S3, batching and mixing, according to production requirements, the raw materials of different particle sizes are fully mixed in proportion, and after mixing, an appropriate amount of binder is added, and the mixture is fully stirred and mixed again, and the raw materials and the binder are evenly distributed; S4, forming, through vibration forming, extrusion forming, compression molding and isostatic pressing, the mixed raw materials are formed into a blank with a certain shape and size, and the blank is in the shape of a plate, block or rod; S5, calcining, placing the green body in a calcining furnace, in an airtight condition or in an environment where an inert protective gas is continuously introduced, heating to 800-1000°C, so that the binder undergoes pyrolysis and polycondensation reaction to form a coke network, thereby giving the green body a certain mechanical strength; S6, graphitization, placing the calcined green body into a graphitization furnace and heating it to 2300-3000°C to transform the carbon atoms from a turbostratic structure to a graphite crystal structure; S7, making blanks, selecting blanks with a density greater than 1.0g / cm³, which can be sawed into graphite sheets of suitable thickness by wire sawing or hacksaw, etc., the graphite sheets can be drilled into cylindrical blanks by multi-head hollow drills for standby use, and the graphite sheets can also be processed into cylindrical blanks by wire sawing or lathe turning; S8, finishing, clamping the graphite cylindrical blank onto the machine tool, and obtaining the finished protective nozzle through the processes of hole opening, tapping, and chamfering; S9, outer layer reinforcement, cutting a short metal tube, and then pressing the obtained protective nozzle into the metal tube (4), using interference fit to fix the two, or processing a grid groove (6) on the outer wall of the obtained protective nozzle, and then embedding the protective net (7) in the grid groove (6).

9. The production process of a double-shielded welding gun shield nozzle according to claim 6, characterized in that: In step S5, the calcined green body may be impregnated, that is, the internal pores thereof may be filled with asphalt or other fillers, and then heated to 800-1000°C for calcination again.

10. The production process of a double-shielded welding gun shield nozzle according to claim 6, characterized in that: In step S8, the finished protective nozzle can be immersed in liquid high temperature resistant glue and then dried, and then placed in a roasting furnace and heated to about 800-1000°C to cause pyrolysis and polycondensation of the high temperature resistant glue to give the graphite protective nozzle mechanical strength.

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