Total cross-section conductive connection structure of aluminum guide rod and steel claw and machining and assembling method

Abstract

The invention discloses a total cross-section conductive connection structure of an aluminum guide rod and a steel claw and a processing and assembling method, and the structure comprises the aluminum guide rod, the lower end of the aluminum guide rod is integrally connected with a first flange plate, and a plurality of first connection holes are formed in the aluminum guide rod; a steel beam of the anode steel claw is integrally connected with a second flange plate, and a plurality of second connecting holes are formed in the second flange plate; a rivet rod of each hot spiral cold extrusion rivet is provided with an external thread structure, the rivet rod correspondingly penetrates through the second connecting hole and upwards penetrates out of the first connecting hole, the external thread structures are provided with internal thread structures on the inner hole wall of the first connecting hole in a self-tapping mode, and the internal thread structures are in threaded meshing connection with the external thread structures; the rivet rod is sleeved with a rivet sleeve, and the inner wall of the rivet sleeve is extruded into the annular groove of the rivet rod through cold extrusion to form a rivet head. And the conducting strip is extruded between the first flange plate and the second flange plate. The structure is high in mechanical strength, conductive in total cross section, uniform in current, high in durability of connection in a high-temperature corrosion environment, and long in life cycle.

Description

Technical Field

[0001] The present invention relates to the technical field of electrolytic aluminum, and more specifically to a full-section conductive connection structure of an aluminum guide rod and a steel claw and a processing and assembling method thereof. Background Art

[0002] In the electrolytic aluminum industry, the aluminum guide rod assembly in the electrolytic cell is used in a harsh environment. It needs to withstand high temperature, corrosion, heavy load, high current, and may have lateral and longitudinal impact forces. The aluminum guide rod assembly will be damaged to varying degrees in various parts. The root of the aluminum guide rod will be welded and cracked, which will increase the pressure drop, consume a lot of aluminum auxiliary materials per ton of electrolytic aluminum, increase energy consumption, and cause high equipment failure rate and high production cost. In the process of electrolytic aluminum production, the deformation and damage rate of anode steel claws is as high as 20%-35%. Repairing it will increase labor costs and work intensity.

[0003] There are generally two ways to connect aluminum guide rods and steel claws:

[0004] One of the technologies currently used is that the aluminum guide rod and the steel claw are connected through the explosive block to form a transition layer, and then argon arc welding is performed, and then the steel and aluminum joints are welded together. Due to the deviation in welding quality, cracks will occur when the carbon anode is lifted and transported under abnormal external forces. Some appear at the welding point between the aluminum rod and the explosive block, and some appear at the joint between the top plane of the steel claw beam and the explosive block. After the cracks occur, the conductivity decreases, the conductivity is uneven, and even fracture occurs, which poses an uncertain risk. At the same time, the explosive block is made of steel and aluminum. In actual working conditions, there is a temperature field of about 500 degrees in this part. The thermal expansion coefficients of the two materials are different, resulting in cracking under the interactive stress of multiple thermal expansion and contraction, increased pressure drop, high product maintenance rate, short life cycle, and failure to achieve full cross-section conductivity, low degree of automation, and high labor costs. In addition, the expansion coefficients of aluminum and steel are quite different. Under the action of high temperature and high current, shear force is generated at the junction of the aluminum and steel materials of the explosive block, resulting in cracking of the welding surface, reduced conductive area, increased resistance, and further aggravation of the fracture trend at the joint.

[0005] The second technology currently used: direct welding of aluminum guide rods and steel claws, that is, steel and aluminum heterogeneous metals, directly eliminates the explosive block and uses "MIG" welding technology. Disadvantages: The mechanical properties of the welded structure cannot meet the requirements of thermocouples and highly corrosive environments, and the service life is short. The aluminum guide rod and steel claw have different thermal expansion coefficients, which leads to cracking under the interactive stress of multiple thermal expansions and contractions, increased pressure drop, and inability to achieve full cross-section conductivity.

[0006] In addition, the related patent technologies are as follows:

[0007] Application No. 202310913947.0 - A flux and welding method suitable for welding anodized aluminum guide rods and anode steel claws, 202310831143.6 - A method for directly connecting anodized aluminum guide rods and steel claws (corresponding to the above-mentioned steel-aluminum direct welding technology No. 2)

[0008] The anode conductive device for aluminum electrolysis disclosed in patent CN216304001U, patent CN214937862U and patent CN216141636U is composed of an aluminum guide rod, an anode steel claw and a steel-aluminum connector. The connection between the anode aluminum guide rod and the anode steel claw is achieved by welding and fixing the lower side of the guide rod to the aluminum rod on the upper part of the steel-aluminum connector, and welding and fixing the upper surface of the steel claw crossbeam to the lower end surface of the steel rod of the steel-aluminum connector. From the disclosed content, it can be seen that this technical solution has the problems of complex structure and high production and manufacturing cost. The conductive area is limited by welding the aluminum rod and the side of the guide rod. If the conductive area of ​​the device is to be increased, the number of steel-aluminum connectors must be increased. The steel-aluminum connector adopts a steel sleeve to improve the strength, which makes the overall weight and size of the device too large, further increasing the difficulty of repairing and replacing the device, which is not conducive to enterprises reducing production costs.

[0009] 202311012388.2-A high-conductivity, current-equalizing steel claw structure and construction method (corresponding to one of the above-mentioned technologies). The aluminum guide rod and the steel claw are connected by an explosive block to form a transition layer, argon arc welding is performed, and a copper plate is added, which has a complicated process.

[0010] 202311350278.7-A high-strength connection method for anode guide rod aluminum-steel induction brazing. The welding process is difficult and complicated, which increases the production cost, fails to achieve full-section conductivity, is difficult to maintain, and has a short service life.

[0011] Chinese patent CN203696261U discloses a transition-free connection method for electrolytic aluminum steel claws and aluminum guide rods, the method is to make a steel sleeve with a threaded inner wall, sleeved on the aluminum guide rod, and apply a 30MPa pressure to the aluminum guide rod at the other end. There is a heat-aiding agent at the bottom of the steel sleeve, and then a large current of 3.5-4.0KA is passed from both ends to make the heat-aiding agent generate heat, so that the temperature of 1200-1300℃ is generated inside the steel sleeve, and a high pressure of 250-350MPa is generated, so that aluminum and steel penetrate violently, forming an atomic bond, thereby achieving a high-strength combination of aluminum and steel. The implementation process of this method is extremely complicated. For the aluminum guide rod with a cross-section of 170×200 in a 400KA electrolytic cell, in order to obtain a pressure of 30MPa and a current of 3.5-4.0KA, its tooling and equipment are difficult to achieve. If it is achieved, its cost is very high and the operability is not strong.

[0012] Chinese patent CN106270890B discloses a method for brazing aluminum and steel, which first cleans the surface of the aluminum material, then chromizes it, and then uses aluminum-based solder as a filler material to connect the aluminum material with the chromized layer with the steel material by brazing process; the method is to put the chromized steel plate and the aluminum alloy into a furnace for brazing; a high-quality joint with a tensile strength of 182-205MPa can be formed. This welding method requires brazing in a furnace, and for aluminum-steel welding in the electrolytic aluminum industry: its aluminum guide rods are roughly divided into 130×130×2538mm; 145×145×2538mm; 220×180×2328mm and other sizes, and the total height with steel claws can reach about 3 meters; the furnace required is relatively high, and the equipment manufacturing is difficult to achieve and the cost is high.

[0013] Chinese patent CN108406027A discloses a method for electrolytic aluminum anode steel-aluminum fusion brazing welding. This invention uniformly coats a layer of flux with a thickness of 100-150 μm on the welding workpiece after removing the surface oxide layer, adopts the method of melting welding of aluminum welding workpiece and brazing of steel welding workpiece, preheats the aluminum and steel welding workpieces respectively, and adopts aluminum-based solid welding wire or aluminum-based flux-cored welding wire to weld steel-aluminum dissimilar metals. This welding method requires preheating of the positive aluminum guide rod and the steel claw, and the size of the anode aluminum guide rod and the steel claw for electrolytic aluminum is relatively large, and the aluminum guide rod is roughly divided into 130×130×2538mm; 145×145×2538mm; 220×180×2328mm and other sizes, and the aluminum guide rod dissipates heat quickly, so preheating the aluminum guide rod is extremely complicated, time-consuming and labor-intensive, and inefficient. Even if it can be achieved, the welding stability is also poor.

[0014] Therefore, how to provide a full-section conductive connection structure and processing and assembly method of aluminum guide rods and steel claws with high structural mechanical strength, full-section conductivity, uniform current, higher connection durability in high temperature and corrosive environments than current processes, and extend the entire life cycle of the product is an issue that technical personnel in this field urgently need to solve. Summary of the invention

[0015] In view of this, the present invention provides a full-section conductive connection structure of an aluminum guide rod and a steel claw as well as a processing and assembly method, which has high structural mechanical strength, full-section conductivity, uniform current, and higher connection durability in high temperature and corrosive environments than current processes, thus extending the entire life cycle of the product.

[0016] In order to achieve the above object, the present invention adopts the following technical solution:

[0017] The full-section conductive connection structure of the aluminum guide rod and the steel claw includes:

[0018] An aluminum guide rod, wherein the lower end of the aluminum guide rod is integrally connected with a first flange plate, and the first flange plate is provided with a plurality of first connection holes;

[0019] An anode steel claw, wherein a second flange plate is integrally connected to the steel beam of the anode steel claw, and a plurality of second connection holes are formed on the second flange plate;

[0020] A plurality of hot spiral cold extrusion rivets, each of which has an external thread structure on its rivet rod, the rivet rod correspondingly passes through the second connection hole and passes upward through the first connection hole, and the external thread structure self-taps an internal thread structure on the inner hole wall of the first connection hole, the internal thread structure is threadedly engaged with the external thread structure, the rivet rod is sleeved with a nail sleeve, and the nail sleeve is squeezed into the annular groove of the rivet rod by cold extrusion to form a rivet head, so as to tightly connect the second flange plate and the first flange plate as a whole;

[0021] A conductive sheet is squeezed between the first flange plate and the second flange plate.

[0022] It can be seen from the above technical scheme that compared with the prior art, the present invention discloses a full-section conductive connection structure of an aluminum guide rod and a steel claw. First, when the first connecting hole is in a hot state, an internal thread structure is extruded and self-tapped on the inner wall of the first connecting hole through the external thread structure on the rivet rod. After the first connecting hole cools and shrinks, the internal thread structure on the inner wall of the first connecting hole shrinks to generate a strong compressive stress and presses and bites the external thread structure, thereby realizing a threaded bite and stable fixed structure of the rivet rod and the first connecting hole. Afterwards, the rivet sleeve is riveted onto the rivet rod to realize hot-installed spiral bite and cold extrusion, so that the first flange plate and the second flange plate are firmly connected as one.

[0023] The present invention achieves high temperature-free deformation and uniform high temperature heat dissipation by changing the mechanical structure of the connection between the aluminum guide rod and the anode steel claw, and installs a conductive sheet between the first flange plate and the second flange plate. During the pressing process of the first flange plate and the second flange, the conductive sheet undergoes plastic deformation and extends and fills the gap between the first flange plate and the second flange plate, thereby achieving full-section contact and continuous conduction between the two.

[0024] The present invention can achieve high-strength connection between the aluminum guide rod and the anode steel claw at the end, prevent the steel claw and the aluminum guide rod from having thermal expansion in a high-temperature environment that affects the connection strength, reduce the flexural deformation of the aluminum guide rod due to high temperature, lateral and longitudinal external forces, and high-temperature thermal deformation of the end contact surface, and achieve full-section conductivity of the connection section between the steel claw and the aluminum guide rod in a thermocouple working environment, thereby reducing voltage drop.

[0025] Therefore, the present invention realizes high-strength connection between the aluminum guide rod and the steel claw without loosening under high temperature, corrosion and heavy load environment, achieves full cross-section contact, thereby effectively reducing voltage drop, and can achieve energy saving and cost reduction in this technical field. This structure has high mechanical strength, full cross-section conductivity, uniform current, and higher durability of connection under high temperature and corrosion environment than the current process, extending the product life cycle.

[0026] Furthermore, an anti-overflow trough is provided on the outer side of the lower hole opening of the first connecting hole, and an anti-overflow boss is provided on the outer side of the upper hole opening of the second connecting hole. The anti-overflow boss is snap-fitted with the anti-overflow trough to prevent the conductive sheet from overflowing due to high temperature under hot conditions, thereby ensuring full-section conductive contact between the first flange plate and the second flange plate.

[0027] The beneficial effect of adopting the above technical solution is that the anti-overflow boss is clamped with the anti-overflow trough, which not only facilitates the rapid positioning and precise assembly of the first connecting hole on the first flange plate and the second connecting hole on the second flange plate, but also, due to the presence of the anti-overflow boss and the anti-overflow trough, it can prevent the conductive sheet from softening and overflowing out of the second connecting hole in a high temperature environment, causing a gap between the first flange plate and the second flange plate, resulting in discontinuous conductivity between the two and increased voltage drop.

[0028] Furthermore, the outer peripheral sides of the connection positions of the first flange plate and the second flange plate are fixed by welding.

[0029] The beneficial effect of adopting the above technical solution is: the outer peripheral side of the connection position of the first flange plate and the second flange plate is welded and fixed, which on the one hand greatly increases the connection strength of the first flange plate and the second flange plate, and on the other hand, the outer peripheral side of the connection position of the first flange plate and the second flange plate can be sealed by the welding material, so that the conductive sheet can be completely sealed and installed between the first flange plate and the second flange plate, preventing the conductive sheet from contacting the external air and oxidizing to affect the conductive effect.

[0030] Furthermore, the outer peripheral side of the second flange plate is arranged to protrude from the outer peripheral side of the first flange plate, and the protruding portion receives the welding material layer.

[0031] The beneficial effects of adopting the above technical solution are: it is conducive to applying flux on the outer sides of the two, which is conducive to welding, and it is also conducive to the accumulation of welding material layers on the outer sides of the two, which is not easy to fall off, thereby realizing fully enclosed welding of the outer sides of the two; and the welding material can also increase conductivity.

[0032] Furthermore, a plurality of heat dissipation reinforcing rib plates are provided between the outer side wall of the aluminum guide rod and the top end surface of the first flange plate.

[0033] The beneficial effects of adopting the above technical solution are: in terms of mechanics, the heat dissipation reinforcement rib plate greatly improves the strength of the aluminum guide rod, and the heat dissipation reinforcement rib plate increases the contact area between the aluminum guide rod and the air, which is beneficial to the use of air convection heat dissipation, improves the temperature field at the connection position of the aluminum guide rod, and ensures that the temperature at the connection between the aluminum guide rod and the steel claw is always within a controllable range.

[0034] The present invention provides a method for processing a full-section conductive connection structure of an aluminum guide rod and a steel claw, and the full-section conductive connection structure of the aluminum guide rod and the steel claw is processed and prepared using the following steps:

[0035] Step 1: Prepare the aluminum guide rod with the first flange plate and the anode steel claw with the second flange plate respectively by mechanical processing or integrated casting, process the first connecting hole on the first flange plate, and process the second connecting hole on the second flange plate;

[0036] Step 2: Processing the conductive sheet;

[0037] Step 3: Processing a hot spiral cold extrusion rivet with the external thread structure.

[0038] Furthermore, in step one, an anti-overflow trough is machined at the lower opening of the first connecting hole, an anti-overflow boss is machined on the top of the second flange plate, and the second connecting hole is machined on the anti-overflow boss.

[0039] Furthermore, in step one, the aluminum guide rod with the first flange plate and the heat dissipation reinforcing rib plate is prepared by machining or integrated casting.

[0040] The present invention provides a method for assembling a full-section conductive connection structure of an aluminum guide rod and a steel claw, and the method comprises the following steps to assemble the full-section conductive connection structure of the aluminum guide rod and the steel claw:

[0041] Step 1: first install the conductive sheet on the second flange plate, then use two bolts to pass through the corresponding first connection hole and the second connection hole respectively, and use nuts to pre-assemble the first flange plate and the second flange plate together;

[0042] Step 2: The first connection hole without bolts installed is heated to a certain temperature by a high-frequency heating device, and the rivet rod of the hot spiral cold extrusion rivet is installed from the second connection hole into the heated first connection hole. At this time, the broken end of the rivet rod passes through the first connection hole, and then the rivet rod is twisted to squeeze the inner wall of the first connection hole that has been heated and expanded through the external thread structure on the rivet rod, so that the inner wall of the first connection hole is plastically deformed and the internal thread structure is self-drilled. After the first connection hole is cooled, its inner wall shrinks, and the internal thread structure squeezes the external thread structure to achieve a stable bite connection;

[0043] Step 3: Put the rivet sleeve on the end of the rivet rod, and use a special tool to cold extrude the rivet sleeve so that the inner wall of the rivet sleeve is plastically deformed and squeezed into the annular groove of the rivet rod to form a rivet head;

[0044] Step 4: Repeat steps 2 and 3 to continue hot-loading and cold-extruding the remaining hot spiral cold-extrusion rivets;

[0045] Step 5: Finally, remove the two bolts pre-installed in step 1, and install hot spiral cold extrusion rivets into the last two holes, so as to fasten the second flange plate and the first flange plate together.

[0046] Furthermore, the method further comprises step six: welding and sealing the outer peripheral sides of the connection positions of the first flange plate and the second flange plate. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0048] Figure 1 A three-dimensional schematic diagram of the full-section conductive connection structure of the aluminum guide rod and four steel claws provided by the present invention.

[0049] Figure 2 for Figure 1 Schematic diagram of the main view.

[0050] Figure 3 for Figure 1 Schematic side view of .

[0051] Figure 4 A schematic cross-sectional view of the assembly of the first flange plate and the second flange plate.

[0052] Figure 5 for Figure 4 Schematic diagram of the enlarged structure of part A in the middle.

[0053] Figure 6 The present invention is a three-dimensional schematic diagram of a full-section conductive connection structure of an aluminum guide rod and six steel claws.

[0054] Figure 7 A three-dimensional schematic diagram of the full-section conductive connection structure of the aluminum guide rod and the eight steel claws provided by the present invention.

[0055] Figure 8 This is a comparison diagram of the pressure drop between the hot spiral riveting connection method adopted by the present invention and the traditional explosion welding connection method.

[0056] Fig. 9 This is a thermal-mechanical finite element analysis diagram of the single anode four-claw / double anode six-claw / double anode eight-claw of the present invention.

[0057] Fig.10 This is the four-claw / six-claw / eight-claw thermocouple diagram of the present invention.

[0058] Fig.11 This is the voltage drop diagram of the single anode four-claw / double anode six-claw / double anode eight-claw explosion block structure.

[0059] Fig.12 This is the shear stress distribution diagram of the aluminum guide rod and the anode steel claw.

[0060] Fig.13 This is the normal stress distribution diagram of the aluminum guide rod and the anode steel claw. DETAILED DESCRIPTION

[0061] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0062] In view of the shortcomings of traditional technology: cracks occur at the welding point between the aluminum guide rod and the explosive block, and cracks occur at the joint between the top plane of the steel claw beam and the explosive block. After the cracks occur, the conductivity of the aluminum guide rod and the steel claw assembly decreases, the conductivity is uneven, and even fracture occurs, which poses uncertain risks. At the same time, the explosive block is made of two materials, steel and aluminum. In actual working conditions, there is a temperature field of about 520 degrees in this part. The two materials have different thermal expansion coefficients, which leads to cracking under the interactive stress of multiple thermal expansions and contractions, increased pressure drop, high product maintenance rate, short life cycle, failure to achieve full cross-section conductivity, low degree of automation in the manufacturing process, and high labor costs. In addition, the thermal expansion coefficients of aluminum and steel are quite different. Under the action of high temperature and high current, shear force is generated at the joint of the explosive block, resulting in cracking of the welding surface, reduced conductive area, increased resistance, and further aggravation of the fracture trend at the joint.

[0063] like Figure 1-Figure 8 As shown, the present invention provides a high-strength connection between the aluminum guide rod and the steel claw without loosening under high temperature, corrosion, and heavy load environments, achieving full-section contact, full-section conductivity, uniform current, and effectively reducing voltage drop, energy saving, and cost reduction. The full-section conductive connection structure of the aluminum guide rod and the steel claw includes:

[0064] An aluminum guide rod 1, the lower end of which is integrally connected with a first flange plate 2, and the first flange plate 2 is provided with a plurality of first connection holes 21;

[0065] Anode steel claw 3 (the steel claw has four claws, six claws, eight claws and other structural forms), the steel beam of the anode steel claw 3 is integrally connected with a second flange plate 4, and the second flange plate 4 is provided with a plurality of second connection holes 41;

[0066] A plurality of hot spiral cold extruded rivets 5, each of which has an external thread structure 51 on its rivet rod (using an existing annular groove rivet with an external thread structure arranged thereon), the rivet rod correspondingly passes through the second connecting hole 41 and passes upward through the first connecting hole 21, and the external thread structure 51 self-taps an internal thread structure 211 on the inner hole wall of the first connecting hole 21, the internal thread structure 211 is threadedly engaged with the external thread structure 51, and the rivet rod is sleeved with a nail sleeve 52, and the nail sleeve 52 is squeezed into the annular groove of the rivet rod through cold extrusion to form a rivet head, so as to tightly connect the second flange plate 4 and the first flange plate 2 as a whole;

[0067] Conductive sheet 6, the conductive sheet 6 is squeezed between the first flange plate 2 and the second flange plate 4, wherein the conductive sheet 6 can be made of aluminum foil or copper foil or other conductive materials with good thermal conductivity, good electrical conductivity and good ductility. In this way, during the pressing process between the first flange plate and the second flange, the aluminum foil or copper foil can cause the conductive sheet to undergo plastic deformation and extend and fill in the gap between the first flange plate and the second flange plate, thereby achieving full cross-section contact and continuous electrical conduction between the two.

[0068] An anti-overflow trough 22 is provided on the outer side of the lower opening of the first connecting hole 21, and an anti-overflow boss 42 is provided on the outer side of the upper opening of the second connecting hole 41. The anti-overflow boss 42 is snap-fitted with the anti-overflow trough 22 to prevent the conductive sheet 6 from overflowing due to high temperature in a hot state, thereby ensuring full-section conductive contact between the first flange plate 2 and the second flange plate 4.

[0069] The outer peripheral sides of the connection positions of the first flange plate 2 and the second flange plate 4 are welded and fixed.

[0070] The outer circumference of the second flange plate 4 is protruded from the outer circumference of the first flange plate 2 , and the protruding portion receives the welding material layer 7 .

[0071] A plurality of heat dissipation reinforcing rib plates 8 are provided between the outer side wall of the aluminum guide rod 1 and the top end surface of the first flange plate 2 .

[0072] The present invention also provides a method for processing a full-section conductive connection structure of an aluminum guide rod and a steel claw, and the full-section conductive connection structure of an aluminum guide rod and a steel claw is processed and prepared using the following steps:

[0073] Step 1: Since the first flange plate 2 and the aluminum guide rod 1 are made of the same aluminum material, and the second flange plate 4 and the anode steel claw 3 are made of the same steel material, the aluminum guide rod 1 with the first flange plate 2 and the anode steel claw 3 with the second flange plate 4 can be prepared directly by machining or integrated casting, which makes the preparation process simple and can be mass-produced. In addition, the integrated structure of the first flange plate and the aluminum guide rod, and the integrated structure of the second flange plate and the anode steel claw also ensure the overall strength of the components and are not easy to break. After that, the first flange plate 2 and the second flange plate 4 are precisely milled using a machining center. The contact surface has a flatness within 0.10 mm. A first connecting hole 21 is machined on the first flange plate 2, and a second connecting hole 41 is machined on the second flange plate 4. The design formula of the bottom hole of the hot spiral cold extrusion rivet 5 before the extrusion thread is D=D1-(1.05-1.1)*P, where D1 is the outer diameter of the annular groove rivet, in mm, and P is the pitch. The apertures of the first connecting hole and the second connecting hole are calculated and processed by a digitally controlled horizontal machining center. The aperture tolerance is controlled at ±0.05 mm. The dimensions without tolerance are processed according to the IT14 tolerance standard accuracy.

[0074] Step 2: Processing the conductive sheet 6, and processing a through hole on the conductive sheet 6 corresponding to the position of the first connecting hole 21;

[0075] Step three: processing a hot spiral cold extruded rivet 5 with an external thread structure 51, that is, optimizing the structure of the existing ring groove rivet, and processing the external thread structure 51 on the smooth shaft part of the rivet.

[0076] In step one, an anti-overflow trough 22 is machined at the lower opening of the first connecting hole 21 , an anti-overflow boss 42 is machined on the top of the second flange plate 4 , and a second connecting hole 41 is machined on the anti-overflow boss 42 .

[0077] In step one, an aluminum guide rod 1 with a first flange plate 2 and a heat dissipation reinforcing rib plate 8 is prepared by machining or integrated casting.

[0078] The present invention also provides an assembly method of a full-section conductive connection structure of a guide rod and a steel claw, and the full-section conductive connection structure of an aluminum guide rod and a steel claw is assembled using the following steps:

[0079] Step 1: first install the conductive sheet 6 on the second flange plate 4, then use two bolts to pass through the corresponding first connecting hole 21 and second connecting hole 41 respectively, and use nuts to pre-assemble the first flange plate 2 and the second flange plate 4 together;

[0080] Step 2: The first connection hole 21 without bolts installed is heated to a certain temperature by a high-frequency heating device, and the rivet rod of the hot spiral cold extrusion rivet 5 is installed into the heated first connection hole 21 from the second connection hole 41. At this time, the broken end of the rivet rod passes through the first connection hole 21, and a centering guide device is installed at this position. Then the rivet rod is screwed (it is necessary to process an external polygonal structure at the end of the rivet rod to facilitate the sleeve screwing tool, and the rivet rod is screwed by the screwing tool). The centering guide device can prevent the rivet rod from tilting and deviating when the rivet rod is screwed, resulting in reduced installation accuracy. The external thread structure 51 on the rivet rod squeezes the inner wall of the first connection hole 21 after heating and expansion, so that the inner wall of the first connection hole 21 is plastically deformed and the internal thread structure 211 is self-drilled. After the first connection hole 21 is cooled, its inner wall shrinks, and the internal thread structure 211 generates a large compressive stress and squeezes the external thread structure 51 to achieve a permanent and stable bite connection, thereby achieving the characteristics of anti-loosening and being able to resist large tension and torsion.

[0081] Step 3: Remove the centering guide device, put a nail sleeve 52 on the end of the rivet rod, use a special tool to cold-extrude the nail sleeve 52, so that the inner wall of the nail sleeve 52 is plastically deformed and squeezed into the annular groove of the rivet rod to form a rivet head;

[0082] Step 4: Repeat steps 2 and 3 to continue hot-loading and cold-extruding the remaining hot spiral cold-extruded rivets 5;

[0083] Step 5: Finally, remove the two bolts pre-installed in step 1, and install hot spiral cold extrusion rivets into the last two holes, so as to fasten the second flange plate 4 and the first flange plate 2 together.

[0084] The assembly method of the full-section conductive connection structure of the aluminum guide rod and the steel claw also includes step six: directly welding the outer peripheral side of the connection position of the first flange plate 2 and the second flange plate 4 with aluminum and steel to seal and fix them.

[0085] When welding,

[0086] S1: Use anhydrous ethanol to clean the outer peripheral side of the connection position of the first flange plate 2 and the second flange plate 4, and then apply flux, the composition of the flux is: potassium fluoroaluminate 76%-85%, zinc powder 13%-19%, aluminum powder 11%-5%, trimethyl borate 1%-2%, mesh size 30-460 mesh; the product purity is above 98% and is evenly ground, mixed and stirred to form a 0.05 mm-0.09 mm solder layer after drying;

[0087] S2: Using the CMT (cold metal transition welding technology) method, the aluminum silicon welding wire is used to form the first layer of weld metal on the surface of the flux layer;

[0088] S3, using CMT (cold metal transition welding technology) method, using pure aluminum welding wire to form a second layer of weld metal on the surface of the first layer of weld metal;

[0089] In step S2, the diameter of the aluminum silicon welding wire is 0.8-1.2 mm; in step S3, the diameter of the pure aluminum welding wire is 1.6-2.0 mm.

[0090] In steps S2 and S3, the parameters of Cmt (cold metal transition welding technology) welding include: welding current 85A-95A, welding voltage 3V-9.8V, and welding speed 5-20mm / s.

[0091] The aluminum silicon welding wire of the present invention has good welding performance, can avoid welding deformation and cracking problems; can reduce the generation of oxide scale: because the surface of the aluminum silicon welding wire contains silicon element, silicon can react with aluminum oxide to generate aluminum silicon compounds that are easy to weld, thereby reducing the generation of oxide scale on the welding surface and improving welding quality and efficiency. In addition, trimethyl borate is added to the flux of the present invention. During the welding process, high temperature will make the metal surface easily react with oxygen and be oxidized. After high-temperature decomposition of trimethyl borate, a protective film can be formed on the metal surface, and this film can prevent further contact between oxygen and metal, thereby improving welding quality. Trimethyl borate mainly plays an anti-oxidation role. After high-temperature decomposition, a protective film is formed on the metal surface to reduce the contact between metal and oxygen; and potassium fluoroaluminate, as a flux, can reduce the melting point and viscosity, protect the molten pool, and improve the weld formation. The functions of the two complement each other, and using them together helps to improve the quality of the weld and obtain a weld with good appearance and few internal defects.

[0092] Pure aluminum welding wire has the following advantages: High purity and excellent oxidation resistance: Pure aluminum welding wire generally refers to welding wire with an aluminum content of more than 99.7%, and its high purity ensures good oxidation resistance. This feature enables a stable arc to be formed during the welding process, effectively reducing the occurrence of oxidation reactions, thereby ensuring welding quality. Good electrical conductivity and thermal conductivity: Pure aluminum welding wire has excellent electrical conductivity and thermal conductivity. Pure aluminum welding wire can perform excellently in short-distance power transmission and occasions requiring good heat conduction. This feature also enables it to transfer heat more effectively during the welding process, promoting the rapid formation and solidification of the weld. Low melting point and good wettability: The melting point of pure aluminum welding wire is relatively low, which makes it easier to melt and form a good fusion with the parent material during the welding process. At the same time, pure aluminum welding wire also has good wettability, which can cover the surface of the parent material more evenly, improving the strength and sealing of the weld.

[0093] Therefore, the present invention first adopts aluminum silicon welding wire for welding, so that a weld layer with strong crack resistance is formed on the peripheral side of the connection position of the first flange plate 2 and the second flange plate 4, and then pure aluminum welding wire is used for secondary welding to form a weld with good strength and sealing, thereby ensuring the strength and sealing of the weld, thereby greatly increasing the connection strength of the first flange plate and the second flange plate on the one hand, and sealing the peripheral side of the connection position of the first flange plate and the second flange plate on the other hand through the welding material, so that the conductive sheet can be completely sealed and installed between the first flange plate and the second flange plate to prevent the conductive sheet from contacting the external air and oxidizing to affect the conductive effect.

[0094] 1. The voltage drop of the present invention is reduced:

[0095] contrast Figure 10-4 The overall pressure drop diagram of claw / six claws / eight claws after using this structure and Figure 11-4 The overall pressure drop diagram of claw / six claws / eight claws using explosive blocks. The comparison between the two shows:

[0096] Fig.10 The overall voltage drop of the middle four claws is 334.27mV, while Fig.11 The overall voltage drop of the middle four claws is 402.18mV.

[0097] Fig.10 The overall voltage drop of the six prongs is 181.39mV, while Fig.11 The overall voltage drop of the six prongs is 204.34mV.

[0098] Fig.10 The overall voltage drop of the middle octopus is 162.48mV, while Fig.11 The overall voltage drop of the middle octagonal claw is 184.82mV.

[0099] It can be seen that the pressure drop of the present structure with four claws, six claws, or eight claws is lower than that of the explosive block.

[0100] In addition, taking the four-claw anode steel claw as an example, the hot ring groove riveting connection method of the present invention is compared with the traditional explosive welding connection. According to finite element analysis, the hot ring groove riveting connection method effectively reduces the voltage drop by 50mV. Figure 8Two different forms of connection structures are given under the same size of aluminum guide rod, anode steel claw, carbon block, phosphorus pig iron parameters. The same eight coordinate points are selected, and their pressure drop characteristics are compared respectively. The right-hand coordinate system is established with the bottom plane of the overall structure, and the y-axis passes through the center of mass of the overall structure. Take eight coordinate points to compare the local pressure drop of the connection of the present invention and the connection form of the explosion block. Among them, coordinate points 1, 2, 3, and 4 correspond to the four coordinate points of the aluminum guide rod; 5 and 6 are the coordinate points of the connection between the aluminum guide rod and the steel claw, respectively, and 7 and 8 are the coordinate points of the steel claw. From the comparison of the pressure drop at each part, it can be seen that in the two connection methods, the pressure drop at the aluminum guide rod structure of the present invention and the connection between the aluminum guide rod and the steel claw is obviously lower than that of the explosion block connection. Among them, the pressure drop difference at the aluminum guide rod in the two structures is about 50mv, and the pressure drop difference at the connection is 20-30mv; the pressure drop at the carbon block is almost the same. It can be seen that the overall pressure drop of the connection method of the present invention is lower than the pressure drop of the explosion block connection form, which is specifically reflected in the aluminum guide rod and the connection.

[0101] It can be seen that the present invention adopts full-section contact, which improves the uneven resistance caused by the uneven steel claw structure and reduces the overall voltage drop compared to the connection method of the explosion block.

[0102] Second, the present invention has good connection rigidity and small deformation in hot state:

[0103] Attached Fig. 9 These are the thermal-mechanical deformation diagrams of four-claw, six-claw, and eight-claw under corresponding loads, and the loads are 1157Kg, 1486Kg, and 2677Kg respectively. At the connection between the aluminum guide rod and the steel claw, the temperature corresponds to 520°. It can be seen from the figure that the maximum deformation position is not at the connection between the aluminum guide rod and the steel claw. The corresponding deformation of the connection between the aluminum guide rod and the steel claw of the four-claw, six-claw, and eight-claw is about 0.47mm, 0.54mm, and 0.61mm respectively. The deformation is small and the connection is reliable.

[0104] 3. The connection between the aluminum guide rod and the steel claw has good conductivity;

[0105] Attached Fig.12 , 13 They are the shear stress distribution diagram of the aluminum guide rod and the anode steel claw, and the normal stress distribution diagram of the aluminum guide rod and the anode steel claw. In most of the middle areas of the figures, the boundary layer shear stress is evenly distributed, and the guide rod, conductive material and anode steel claw are tightly fitted in most areas, with good conductivity.

[0106] Therefore, the present invention achieves high-temperature non-deformation and uniform heat dissipation by changing the mechanical structure of the connection between the aluminum guide rod and the steel claw, adopting annular groove rivets made of high-strength and high-temperature resistant materials, adopting the principle of thermal interference fit and the assembly method of riveting to connect the aluminum guide rod and the anode steel claw, installing conductive materials such as aluminum foil (or copper foil) between the aluminum guide rod and the anode steel claw, and performing direct welding of aluminum and steel or sealing the holes and the periphery with high-temperature paint around the connection between the aluminum guide rod and the steel claw. The present invention can achieve high-strength connection of the aluminum guide rod at the end connected with the steel claw, prevent the thermal expansion of the steel claw and the aluminum guide rod in a high-temperature environment from affecting the connection strength, reduce the flexural deformation of the aluminum guide rod due to high-temperature lateral and longitudinal external forces and high-temperature thermal deformation of the end contact surface, and achieve full-section conductivity of the connection section of the steel claw and the aluminum guide rod in a thermocouple working environment, thereby reducing voltage drop.

[0107] The present invention realizes high-strength connection between the aluminum guide rod and the steel claw without loosening under high temperature, corrosion and heavy load environment, achieves full cross-section contact, thereby effectively reducing voltage drop, and can achieve energy saving and cost reduction in this technical field. This structure has high mechanical strength, full cross-section conductivity, uniform current, and higher durability of connection under high temperature and corrosion environment than the current process, extending the product life cycle.

[0108] In this specification, each embodiment is described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the embodiments can be referred to each other. For the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple, and the relevant parts can be referred to the method part.

[0109] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. The full-section conductive connection structure of the aluminum guide rod and the steel claw is characterized by: include: An aluminum guide rod (1), the lower end of the aluminum guide rod (1) being integrally connected to a first flange plate (2), the first flange plate (2) being provided with a plurality of first connection holes (21); An anode steel claw (3), wherein a second flange plate (4) is integrally connected to a steel beam of the anode steel claw (3), and a plurality of second connection holes (41) are formed on the second flange plate (4); A plurality of hot spiral cold extruded rivets (5), each of the rivet rods of the hot spiral cold extruded rivets (5) being provided with an external thread structure (51), the rivet rod correspondingly passing through the second connecting hole (41) and passing upward through the first connecting hole (21), and the external thread structure (51) self-taps an internal thread structure (211) on the inner hole wall of the first connecting hole (21), the internal thread structure (211) and the external thread structure (51) being threadedly engaged with each other, the rivet rod being provided with a nail sleeve (52), the nail sleeve (52) being pressed into the annular groove of the rivet rod through cold extrusion to form a rivet head, so as to tightly connect the second flange plate (4) and the first flange plate (2) into one body; A conductive sheet (6), wherein the conductive sheet (6) is squeezed between the first flange plate (2) and the second flange plate (4).

2. The full-section conductive connection structure of the aluminum guide rod and the steel claw according to claim 1 is characterized in that: An anti-overflow trough (22) is provided on the outer side of the lower opening of the first connecting hole (21), and an anti-overflow boss (42) is provided on the outer side of the upper opening of the second connecting hole (41). The anti-overflow boss (42) is snap-fitted with the anti-overflow trough (22) to prevent the conductive sheet (6) from overflowing due to high temperature in a hot state, thereby ensuring full-section conductive contact between the first flange plate (2) and the second flange plate (4).

3. The full-section conductive connection structure of the aluminum guide rod and the steel claw according to claim 1 or 2, characterized in that: The outer peripheral sides of the connection positions of the first flange plate (2) and the second flange plate (4) are welded and fixed.

4. The full-section conductive connection structure of the aluminum guide rod and the steel claw according to claim 3 is characterized in that: The outer peripheral side of the second flange plate (4) is arranged to protrude from the outer peripheral side of the first flange plate (2), and the protruding portion receives a welding material layer (7).

5. The full-section conductive connection structure of the aluminum guide rod and the steel claw according to claim 1, 2 or 4, characterized in that: A plurality of heat dissipation reinforcing rib plates (8) are provided between the outer side wall of the aluminum guide rod (1) and the top end surface of the first flange plate (2).

6. A method for processing a full-section conductive connection structure of an aluminum guide rod and a steel claw, characterized in that: The full-section conductive connection structure of the aluminum guide rod and the steel claw as described in any one of claims 1 to 5 is prepared by the following steps: Step 1: The aluminum guide rod (1) with the first flange plate (2) and the anode steel claw (3) with the second flange plate (4) are respectively prepared by mechanical processing or integrated casting, and the first connecting hole (21) is processed on the first flange plate (2), and the second connecting hole (41) is processed on the second flange plate (4); Step 2: Processing the conductive sheet (6); Step three: processing a hot spiral cold extrusion rivet (5) with the external thread structure (51).

7. The method for processing the full-section conductive connection structure of the aluminum guide rod and the steel claw according to claim 6, characterized in that: In step one, an anti-overflow trough (22) is machined at the lower opening of the first connecting hole (21), an anti-overflow boss (42) is machined on the top of the second flange plate (4), and the second connecting hole (41) is machined on the anti-overflow boss (42).

8. The method for processing the full-section conductive connection structure of the aluminum guide rod and the steel claw according to claim 6, characterized in that: In step one, the aluminum guide rod (1) with the first flange plate (2) and the heat dissipation reinforcing rib plate (8) is prepared by mechanical processing or integrated casting.

9. A method for assembling a full-section conductive connection structure of an aluminum guide rod and a steel claw, characterized in that: The full-section conductive connection structure of the aluminum guide rod and the steel claw as described in any one of claims 1 to 5 is assembled using the following steps; Step 1: firstly install the conductive sheet (6) on the second flange plate (4), then respectively pass two bolts through the corresponding first connection hole (21) and the second connection hole (41), and pre-assemble the first flange plate (2) and the second flange plate (4) together using nuts; Step 2: The first connection hole (21) without a bolt installed is heated to a certain temperature by a high-frequency heating device, and the rivet rod of the hot spiral cold extrusion rivet (5) is inserted into the heated first connection hole (21) from the second connection hole (41). At this time, the broken end of the rivet rod passes through the first connection hole (21), and then the rivet rod is twisted to extrude the inner wall of the first connection hole (21) after heating and expansion through the external thread structure (51) on the rivet rod, so that the inner wall of the first connection hole (21) is plastically deformed and the internal thread structure (211) is self-tapped. After the first connection hole (21) is cooled, its inner wall shrinks, and the internal thread structure (211) squeezes the external thread structure (51) to achieve a stable bite connection; Step 3: Sleeve the rivet sleeve (52) on the end of the rivet rod, and use a special tool to cold-extrude the rivet sleeve (52) so that the inner wall of the rivet sleeve (52) is plastically deformed and squeezed into the annular groove of the rivet rod to form a rivet head; Step 4: Repeat steps 2 and 3 to continue hot-loading and cold-extruding the remaining hot spiral cold-extruded rivets (5); Step 5: Finally, remove the two bolts pre-installed in step 1, and install hot spiral cold extrusion rivets into the last two holes, so as to fasten the second flange plate (4) and the first flange plate (2) together.

10. The method for assembling the full-section conductive connection structure of the aluminum guide rod and the steel claw according to claim 9, characterized in that: The method further comprises step six: welding and sealing the outer peripheral sides of the connection positions of the first flange plate (2) and the second flange plate (4).

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