阅读说明：本技术 一种焊丝自预热气保焊导电嘴 (Welding wire is from preheating gas shield welding contact tip ) 是由 葛佳棋 万升云 汤旭祥 桑劲鹏 李广立 祁三军 邵戗 彭蝶 于 2021-09-13 设计创作，主要内容包括：本发明属于熔化极气保焊设备技术领域。本发明提供一种焊丝自预热气保焊导电嘴,包括导电嘴本体,沿导电嘴本体的轴心开设有焊丝通孔,导电嘴本体的一端设有导电嘴前段,另一端设有导电嘴后段；导电嘴后段沿焊丝通孔同轴长度方向设有后段沉孔,后段沉孔内通过过盈装配嵌有后段陶瓷管,后段陶瓷管的内孔直径等于所述焊丝通孔的直径；导电嘴前段沿焊丝通孔同轴长度方向设有前段沉孔,前段沉孔内装配有开设焊丝贯穿孔的前段陶瓷构件。本发明可使焊丝在通过导电嘴时,与导电嘴的电接触位置被限制在焊丝通孔长度范围内,使焊丝的电接触位置到焊丝前端的距离增加,即在不影响气体保护的前提下增加了焊丝的干伸长。(The invention belongs to the technical field of gas shielded welding equipment for consumable electrodes. The invention provides a welding wire self-preheating gas shielded welding contact tip, which comprises a contact tip body, wherein a welding wire through hole is formed in the axis of the contact tip body, one end of the contact tip body is provided with a front contact tip section, and the other end of the contact tip body is provided with a rear contact tip section; the rear section of the contact nozzle is provided with a rear section counter bore along the coaxial length direction of the welding wire through hole, a rear section ceramic tube is embedded in the rear section counter bore through interference fit, and the diameter of an inner hole of the rear section ceramic tube is equal to that of the welding wire through hole; the front section of the contact nozzle is provided with a front section counter bore along the coaxial length direction of the welding wire through hole, and a front section ceramic component provided with a welding wire through hole is assembled in the front section counter bore. The invention can limit the electric contact position of the welding wire with the contact tip within the length range of the through hole of the welding wire when the welding wire passes through the contact tip, so that the distance from the electric contact position of the welding wire to the front end of the welding wire is increased, namely, the dry extension of the welding wire is increased on the premise of not influencing gas protection.)

1. The utility model provides a welding wire is from preheating gas shield welding contact tip, includes the contact tip body, follows the welding wire through-hole has been seted up in the axle center of contact tip body, its characterized in that: one end of the contact tube body is provided with a front contact tube section, and the other end of the contact tube body is provided with a rear contact tube section;

the rear section of the contact nozzle is provided with a rear section counter bore along the coaxial length direction of the welding wire through hole, a rear section ceramic tube is embedded in the rear section counter bore through interference fit, and the diameter of an inner hole of the rear section ceramic tube is equal to that of the welding wire through hole;

the front section of the contact nozzle is provided with a front section counter bore along the coaxial length direction of the welding wire through hole, and a front section ceramic component provided with a welding wire through hole is assembled in the front section counter bore.

2. The welding wire self-preheating gas shield welding contact tip as recited in claim 1, wherein: the front section of the contact tube is a conical part of an integrated structure with the contact tube body, the front end of the conical part is arranged in the direction of the contact tube body, the front section counter bore is coaxial with the welding wire through hole, the front section ceramic component is embedded in the front section counter bore, the front section ceramic component is a columnar ceramic tube, and the diameter of the welding wire through hole of the columnar ceramic tube is the same as that of the welding wire through hole.

3. The welding wire self-preheating gas shield welding contact tip as recited in claim 1, wherein: the conducting nozzle is characterized in that the front section counter bore of the front section of the conducting nozzle is an internal thread hole, the front section ceramic component is an insulated ceramic conducting nozzle cap which is connected with the front section counter bore in a screwing mode, the insulated ceramic conducting nozzle cap comprises an external thread connecting part and a front conical part, the external thread connecting part is connected with the internal thread hole of the front section counter bore in a screwing mode, a central through hole is formed in the insulated ceramic conducting nozzle cap, and the central through hole is coaxial with the welding wire through hole and has the same diameter.

4. The welding wire self-preheating gas shield welding contact tip as recited in claim 2, wherein: the length of the columnar ceramic tube accounts for 40-50% of the length of the contact tube, the length of the rear-section ceramic tube accounts for 10-25% of the length of the contact tube, and the length of the welding wire through hole accounts for 25-50% of the length of the contact tube.

5. The welding wire self-preheating gas shield welding contact tip as set forth in claim 3, wherein: the length of the insulating ceramic conductive nozzle cap accounts for 40-50% of the length of the conductive nozzle, the length of the rear-section ceramic tube accounts for 10-25% of the length of the conductive nozzle, and the length of the welding wire through hole accounts for 25-50% of the length of the conductive nozzle.

6. The welding wire self-preheating gas shield welding contact tip as recited in claim 1, wherein: and a chamfer is arranged at the tail end face of the inner hole of the rear-section ceramic tube.

7. The welding wire self-preheating gas shield welding contact tip as recited in claim 1, wherein: the rear section of the contact tube is of a cylindrical structure provided with external threads.

8. The welding wire self-preheating gas shield welding contact tip as recited in claim 1, wherein: the diameter of the welding wire through hole is 0.8-1.6 mm.

Technical Field

The invention belongs to the technical field of gas shielded welding equipment for consumable electrodes, and particularly relates to a welding wire self-preheating gas shielded welding contact tip.

Background

In the existing gas metal arc welding equipment, a contact tip is usually made of a single copper material, the contact tip is used for conducting welding current to a welding wire (electrode), electric arc is generated between the welding wire and a workpiece, so that the front end of the welding wire is melted at the high temperature of the electric arc to form molten drops and is transferred into a molten pool, and the molten pool is cooled and then solidified to form a welding line. During this process, the wire is continuously fed through the wire feeder to maintain a normal arc length.

The heat to melt the wire is usually composed of two parts, one is arc heat, the magnitude of which is proportional to the welding current; and secondly, resistance heat, the magnitude of which is in direct proportion to the product value of the square of the welding current and the dry extension of the welding wire, wherein the longer the dry extension of the welding wire is in a certain range, the larger the resistance heat is under the condition of certain welding current. Dry elongation is the length of wire extending out of the contact tip, which length of wire is in a conductive state during welding, according to the definition in the AWS 3.0 welding terminology and definitions standard. In a welding operation, under the condition of a certain welding voltage, the farther a welding gun is away from a workpiece, the longer the welding wire is subjected to dry elongation, and theoretically, the greater the resistance heat received by the welding wire is, the higher the deposition rate is. However, as the distance between the welding gun and the workpiece increases, the arc may become unstable and the gas shielding effect may be affected, so that in the actual welding operation, it is not feasible to increase the resistance heat of the welding wire and the deposition rate of the welding wire by simply increasing the height of the welding gun and increasing the dry extension of the welding wire without changing the welding process parameters.

Disclosure of Invention

The purpose of the invention is as follows: aiming at the problems and the defects in the prior art, the invention provides the welding wire self-preheating gas shield welding contact tip, which solves the problems in the background art by changing the structure of the contact tip, increasing the conductive length of the welding wire and improving the resistance heat generated by the welding wire before melting.

The technical scheme is as follows: a welding wire self-preheating gas shielded welding contact tip comprises a contact tip body, wherein a welding wire through hole is formed in the axis of the contact tip body, a contact tip front section is arranged at one end of the contact tip body, and a contact tip rear section is arranged at the other end of the contact tip body;

the rear section of the contact nozzle is provided with a rear section counter bore along the coaxial length direction of the welding wire through hole, a rear section ceramic tube is embedded in the rear section counter bore through interference fit, and the diameter of an inner hole of the rear section ceramic tube is equal to that of the welding wire through hole;

the front section of the contact nozzle is provided with a front section counter bore along the coaxial length direction of the welding wire through hole, and a front section ceramic component provided with a welding wire through hole is assembled in the front section counter bore.

Preferably, the front section of the contact tube is a conical part of an integral structure with the contact tube body, the front section counter bore coaxial with the welding wire through hole is formed from the front end of the conical part to the contact tube body, the front section ceramic component is embedded in the front section counter bore, the front section ceramic component is a cylindrical ceramic tube, and the diameter of the welding wire through hole of the cylindrical ceramic tube is the same as that of the welding wire through hole.

Preferably, the front-section counter bore of the front section of the contact nozzle is an internal threaded hole, the front-section ceramic component is an insulating ceramic conductive nozzle cap screwed with the front-section counter bore, the insulating ceramic conductive nozzle cap comprises an external thread connecting part and a front conical part, the external thread connecting part is screwed in the internal threaded hole of the front-section counter bore, a central through hole is formed in the insulating ceramic conductive nozzle cap, and the central through hole is coaxial with the welding wire through hole and has the same diameter.

Preferably, the length of the contact tip is 40mm, the length of the columnar ceramic tube accounts for 40% -50% of the length of the contact tip, the length of the rear-section ceramic tube accounts for 10% -25% of the length of the contact tip, and the length of the welding wire through hole accounts for 25% -50% of the length of the contact tip.

Preferably, the length of the contact nozzle is 40mm, the length of the insulating ceramic contact nozzle cap accounts for 40% -50% of the length of the contact nozzle, the length of the rear-section ceramic tube accounts for 10% -25% of the length of the contact nozzle, and the length of the welding wire through hole accounts for 25% -50% of the length of the contact nozzle.

Preferably, a chamfer is arranged at the tail end face of the inner hole of the rear-section ceramic tube.

Preferably, the rear section of the contact tube is of a cylindrical structure provided with an external thread.

Preferably, the diameter of the welding wire through hole is 0.8-1.6 mm.

Has the advantages that: compared with the prior art, the invention has the following advantages:

the welding wire self-preheating gas shield welding contact tip provided by the invention has the advantages that the counter bore is arranged at the rear section of the contact tip and is embedded into the rear section of the ceramic tube, the counter bore is also arranged at the front section of the contact tip and is embedded into the cylindrical ceramic tube, or the front section of the contact tip is machined and then is in threaded connection with the insulating ceramic contact tip cap, so that the electric contact position of the welding wire and the contact tip is limited within the length range of a through hole of the welding wire when the welding wire passes through the contact tip, the distance between the electric contact position of the welding wire and an electric arc is increased, namely, the dry extension of the welding wire is increased on the premise of not influencing gas protection, the resistance heat borne by the welding wire is increased, the effect is equal to preheating the welding wire before melting, the deposition rate of the welding wire is accelerated, and the welding efficiency can be improved. In addition, the electric contact position of the contact tip is limited in the welding wire through hole, so that the excessive change of the electric contact point of the welding wire and the contact tip can be avoided, and the stability of the electric arc is improved.

Drawings

FIG. 1 is a schematic view of the overall structure of embodiments 1 and 2 of the present invention;

FIG. 2 is a schematic structural diagram of a contact tip body according to embodiments 1 and 2 of the present invention;

FIG. 3 is a schematic structural view of a rear-stage ceramic tube according to embodiments 1 to 4 of the present invention;

FIG. 4 is a schematic structural view of a cylindrical ceramic tube according to embodiments 1 and 2 of the present invention;

FIG. 5 is a schematic view of the overall structure of embodiments 3 and 4 of the present invention;

FIG. 6 is a schematic structural diagram of the contact tip body according to embodiments 3 and 4 of the present invention;

fig. 7 is a schematic structural diagram of an insulating ceramic conductive nozzle cap according to embodiments 3 and 4 of the present invention.

In the figure: 1-contact nozzle body, 11-contact nozzle rear section, 111-rear section counter bore, 12-contact nozzle front section, 12-1-conical part, 121-front section counter bore, 13-welding wire through hole, 2-rear section ceramic tube, 21-inner hole of rear section ceramic tube, 22-chamfer, 3-cylindrical ceramic tube, 31-welding wire through hole, 1-1-internal threaded hole, 4-insulating ceramic contact nozzle cap, 41-external thread connecting part, 42-front conical part and 43-central through hole.

Detailed Description

The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments of the present invention without making any creative effort, shall fall within the protection scope of the present invention.

Example 1

As shown in fig. 1-4, the embodiment provides a welding wire self-preheating gas shield welding contact tip, which includes a contact tip body 1, one end of the contact tip body 1 is a contact tip rear section 11 connected to a welding gun, the other end is a contact tip front section 12, the contact tip rear section 11 is cylindrical, and is provided with an external thread screwed to the welding gun. The axis of the contact tube body 1 is provided with a welding wire through hole 13, the axis position of the rear section 11 of the contact tube is reamed to form a rear section counter bore 111, the rear section counter bore 111 and the welding wire through hole 13 are coaxial, and the rear section counter bore 111 is embedded into the rear section ceramic tube 2.

Preferably, the length of the contact tip body 1 in the embodiment is 20mm, the length of the rear-section counter bore 111 of the contact tip is 10mm, the length of the rear-section ceramic tube 2 is the same as that of the rear-section counter bore 111, the diameter of the rear-section counter bore is 0.1-0.3 mm larger than that of the rear-section counter bore 111, the rear-section counter bore diameter of the rear-section baked contact tip is expanded and enlarged by heat before assembly, the rear-section ceramic tube is knocked in by a rubber hammer, the rear section of the contact tip is cooled down and contracted to tightly wrap and fix the rear-section ceramic tube, and the diameter of an inner hole 21 of the rear-section ceramic tube is the same as that of the welding wire through hole 13 and is 1.2 mm.

Preferably, the front section 12 of the contact tip in this embodiment is a tapered portion 12-1 integrated with the contact tip body 1, a front section counter bore 121 is formed in the front end of the tapered portion 12-1 along the coaxial direction of the welding wire through hole, a cylindrical ceramic tube 3 is embedded in the front section counter bore 121, and the diameter of the welding wire through hole 31 of the cylindrical ceramic tube 3 is the same as that of the welding wire through hole 13.

Preferably, the length of the front-stage counterbore 121 in the present embodiment is 20mm, and the columnar ceramic tube 3 having the same length is pressed into the front-stage counterbore 121 by a rubber hammer, in the same manner as when the rear-stage ceramic tube 2 is pressed into the rear-stage counterbore 111, the diameter of the columnar ceramic tube 3 is 0.1 to 0.3mm larger than that of the front-stage counterbore 121.

Preferably, the diameter of the wire through hole 31 of the columnar ceramic tube 3 in the present embodiment is 1.2mm, which is the same as the diameter of the wire through hole 13.

Preferably, the rear section of the rear ceramic tube in the contact tube in the embodiment has a chamfer 22 at the end face of the tail part of the inner hole 21.

Preferably, the insulating ceramic material in the present embodiment may use alumina Al₂O₃Or silicon nitride Si₃N₄And the like.

Example 2

The contact tip structure in this embodiment is substantially the same as that in embodiment 1, as shown in fig. 1 to 4: the length of the contact tube body 1 in this embodiment is 20mm, the length of the rear-section counter bore 111 of the contact tube is 4mm, the length of the rear-section ceramic tube 2 is the same as that of the rear-section counter bore 111, the diameter of the rear-section counter bore 111 is 0.1-0.3 mm larger than that of the rear-section counter bore 111, the rear-section counter bore diameter is expanded and enlarged by heat, the rear-section ceramic tube is knocked in by a rubber hammer, the rear section of the contact tube is cooled down and contracted, the rear-section ceramic tube is tightly wrapped and fixed, and the diameter of the inner hole 21 of the rear-section ceramic tube is the same as that of the welding wire through hole 13 and is 1.2 mm.

Preferably, the front section 12 of the contact tip in this embodiment is a tapered portion 12-1 integrated with the contact tip body 1, a front section counter bore 121 is formed in the front end of the tapered portion 12-1 along the coaxial direction of the welding wire through hole, a cylindrical ceramic tube 3 is embedded in the front section counter bore 121, and the diameter of the welding wire through hole 31 of the cylindrical ceramic tube 3 is the same as that of the welding wire through hole 13.

Preferably, the length of the front-stage counterbore 121 in the present embodiment is 16mm, and the columnar ceramic tube 3 having the same length is pressed into the front-stage counterbore 121 by a rubber hammer, in the same manner as when the rear-stage ceramic tube 2 is pressed into the rear-stage counterbore 111, the diameter of the columnar ceramic tube 3 is 0.1 to 0.3mm larger than that of the front-stage counterbore 121.

Preferably, the diameter of the wire through hole 31 of the columnar ceramic tube 3 in the present embodiment is 1.2mm, which is the same as the diameter of the wire through hole 13.

Preferably, the rear section of the rear ceramic tube in the contact tube in the embodiment has a chamfer 22 at the end face of the tail part of the inner hole 21.

Preferably, the insulating ceramic material in the present embodiment may use alumina Al₂O₃Or silicon nitride Si₃N₄And the like.

Example 3

As shown in fig. 3, 5, 6, and 7, the present embodiment provides a welding wire self-preheating gas shielded welding contact tip, which includes a contact tip body 1, wherein one end of the contact tip body 1 is a contact tip rear section 11, and the other end is a contact tip front section. The rear contact tube section 11 has the same structure as that of the rear contact tube section in embodiment 1, and is a cylindrical external thread structure. This embodiment is different from embodiments 1 and 2 in that:

the front-end-face axial center position of the front section of the conductive nozzle of the present embodiment is provided with a front-section counter bore, the front-section counter bore of the present embodiment is an internal threaded hole 1-1, a front-section ceramic member is screwed in the internal threaded hole 1-1, the front-section ceramic member of the present embodiment is an insulating ceramic conductive nozzle cap 4, the insulating ceramic conductive nozzle cap 4 comprises an external thread connecting portion 41 and a front conical portion 42, the external thread connecting portion 41 is screwed in the internal threaded hole 1-1 of the front-section counter bore, a central through hole 43 is formed in the insulating ceramic conductive nozzle cap 4, and the diameter of the central through hole 43 is the same as the diameter of the welding wire through hole 13.

As shown in fig. 2, 4 and 5, this embodiment corresponds to the embodiment 1 in which the tapered portion 12-1 of the front segment of the contact tip is removed by cutting, the female screw hole 1-1 is formed in the axial center position of the tip end surface of the contact tip body 1, and then the male screw connecting portion 41 is screwed into the female screw hole 1-1. The front tapered portion 42 can be made to have the same contour as the cut tapered portion 12-1, i.e. the appearance contour of the assembled structure after the insulating ceramic contact tip cap 4 is screwed with the contact tip body 1 is substantially the same as that of embodiments 1 and 2.

Preferably, the length of the contact tube body 1 in the embodiment is 20mm, the length of the rear-section counter bore 111 of the contact tube is 10mm, the length of the rear-section ceramic tube 2 is the same as that of the rear-section counter bore 111, and the diameter of the rear-section ceramic tube is 0.1-0.3 mm larger than that of the rear-section counter bore 111.

Preferably, the diameter of the inner hole 21 of the rear-stage ceramic tube in the present embodiment is 1.2mm, which is the same as the diameter of the wire through hole 13.

Preferably, the central through hole 43 of the insulated ceramic nozzle cap in this embodiment has a length of 20mm and a diameter of 1.2mm, which is the same as the wire through hole 13.

Example 4

The structure of the embodiment is the same as that of the embodiment 3, as shown in fig. 3, 5, 6 and 7, the length of the contact tube body 1 in the embodiment is 20mm, the length of the rear-section counter bore 111 of the contact tube is 4mm, the length of the rear-section ceramic tube 2 is the same as that of the rear-section counter bore 111, and the diameter of the rear-section ceramic tube is 0.1-0.3 mm larger than that of the rear-section counter bore 111.

Preferably, the diameter of the inner hole 21 of the rear-stage ceramic tube in the present embodiment is 1.2mm, which is the same as the diameter of the wire through hole 13.

Preferably, the central through hole 43 of the insulated ceramic nozzle cap in this embodiment has a length of 16mm and a diameter of 1.2mm, which is the same as the wire through hole 13.

When the invention is used for welding, the welding wire passes through the inner hole 21 of the rear-stage ceramic tube, reaches the welding wire through hole 13 and is conductive, and then passes through the welding wire through hole 31 of the columnar ceramic tube 3 or passes through the central through hole 43 of the insulating ceramic conductive nozzle cap 4 to extend out.

In examples 1 and 3, the length of the wire through hole 31 of the cylindrical ceramic tube 3 or the center through hole 43 of the insulating ceramic conductive nozzle cap 4 was 20mm, and in examples 2 and 4, the length of the wire through hole 31 of the cylindrical ceramic tube 3 or the center through hole 43 of the insulating ceramic conductive nozzle cap 4 was 16mm, that is, the conductive point of the wire was raised by 20mm in examples 1 and 3, and 16mm in examples 2 and 4.

In order to verify the difference between the welding effects of the embodiment of the invention and the common contact nozzle, the technical schemes of the embodiments 1 to 4 and the common contact nozzle are respectively adopted to carry out flat plate build-up welding tests under the same welding parameters, the plate adopted in the tests is a Q235 low-carbon steel plate, the welding wire adopts ER50-6, the diameter is 1.2mm, and the welding parameters are set as shown in Table 1.

TABLE 1 Flat surfacing test welding parameters

Current (A)	Voltage (V)	Welding speed (cm/min)
			280	29	40

And recording the current, the voltage and the wire feeding speed in the test process, measuring the penetration and the residual height of the welding seam after welding, and obtaining the test results shown in table 2.

TABLE 2 test results

	Current (A)	Voltage (V)	Wire feed speed (m/min)	Penetration (mm)	Residual height (mm)
						Example 1	226	30.2	8.8	2.1	4.3
Example 2	246	29.9	7.6	2.5	3.8
						Example 3	231	30.4	8.7	2.3	4.2
Example 4	249	30	7.9	2.5	3.7
						Common contact tip	278	29.4	6.8	3.3	3.0

When a common contact tip is used for welding, a welding wire passes through the contact tip, and a contact point with the contact tip can appear at any position in a through hole of the contact tip, which is also one reason for fluctuation of an electric arc.

Tests show that in the embodiments 1-4 of the invention, the front section of the contact nozzle is inserted into the front section of the columnar ceramic tube or the insulating ceramic contact nozzle cap is used, so that the conductive point of the welding wire is limited in the range of the through hole of the welding wire, namely, the length from the conductive point to the electric arc is prolonged, and the conductive length is increased. The rear-section ceramic tube embedded in the rear section of the contact tube body shortens the length of the welding wire through hole, and avoids overlarge position change of a conductive point when the welding wire passes through the welding wire through hole.

Therefore, the following comparative experiments and tables 1 and 2 were carried out: compared with a common contact tube, the welding process adopting the technical schemes of the embodiments 1 to 4 has the advantages that the welding current is reduced to some extent, the wire feeding speed is increased, and the experimental results of the comparison of the embodiment 1 and 3 and the embodiment 2 and 4 show that the higher the conducting point is, the faster the wire feeding speed is, so that the preheating of the welding wire can be effectively realized by adopting the technical scheme of the invention, and the effect of increasing the deposition rate of the welding wire is achieved.

The foregoing is only a preferred embodiment of this invention and it should be noted that modifications can be made by those skilled in the art without departing from the principle of the invention and these modifications should also be considered as the protection scope of the invention.