CN113130912B - Lead pipe of lead-acid storage battery and manufacturing method - Google Patents
Lead pipe of lead-acid storage battery and manufacturing method Download PDFInfo
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- CN113130912B CN113130912B CN202110308192.2A CN202110308192A CN113130912B CN 113130912 B CN113130912 B CN 113130912B CN 202110308192 A CN202110308192 A CN 202110308192A CN 113130912 B CN113130912 B CN 113130912B
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/64—Carriers or collectors
- H01M4/82—Multi-step processes for manufacturing carriers for lead-acid accumulators
- H01M4/84—Multi-step processes for manufacturing carriers for lead-acid accumulators involving casting
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22C—FOUNDRY MOULDING
- B22C9/00—Moulds or cores; Moulding processes
- B22C9/22—Moulds for peculiarly-shaped castings
- B22C9/24—Moulds for peculiarly-shaped castings for hollow articles
-
- C—CHEMISTRY; METALLURGY
- C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
- C22C—ALLOYS
- C22C11/00—Alloys based on lead
- C22C11/08—Alloys based on lead with antimony or bismuth as the next major constituent
- C22C11/10—Alloys based on lead with antimony or bismuth as the next major constituent with tin
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01M—PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSION OF CHEMICAL ENERGY INTO ELECTRICAL ENERGY
- H01M4/00—Electrodes
- H01M4/02—Electrodes composed of, or comprising, active material
- H01M4/64—Carriers or collectors
- H01M4/66—Selection of materials
- H01M4/68—Selection of materials for use in lead-acid accumulators
- H01M4/685—Lead alloys
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- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E60/00—Enabling technologies; Technologies with a potential or indirect contribution to GHG emissions mitigation
- Y02E60/10—Energy storage using batteries
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Materials Engineering (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Electrochemistry (AREA)
- General Chemical & Material Sciences (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Cell Electrode Carriers And Collectors (AREA)
Abstract
A lead tube of a lead-acid storage battery and a manufacturing method thereof belong to the technical field of preparation of parts of the lead-acid storage battery for automobile starting. The lead pipe is prepared by adopting a cold extrusion process, and comprises the following chemical components in percentage by weight: 2.0% -6.0%; sn:0.02 to 0.3 percent; as:0.1 to 0.25 percent; 0 to 0.03 percent of Se; bi is less than or equal to 0.2 percent, and the balance is Pb. The main process flow of the preparation method comprises the steps of melting materials, spraying a mold, casting, extruding, opening the mold and ejecting out a product. And by optimizing parameters of high-pressure die locking pressure, low-pressure die locking pressure, quick die locking pressure and slow die locking pressure of the die casting machine, the prepared lead pipe has the characteristics of high overall dimension precision, good gloss and high internal strength.
Description
Technical Field
The invention relates to the technical field of storage battery part preparation, in particular to a lead pipe of a lead-acid storage battery for automobile starting and a cold extrusion manufacturing process thereof.
Background
The lead-acid storage battery is used as a power source for starting an automobile, and the service performance, the stability and the service life of the lead-acid storage battery are greatly developed through years of research. The terminal-lead tube on the lead-acid storage battery plays a key role in charging and discharging the storage battery; the traditional lead pipe production process adopts a natural gravity casting method, and a die casting process is adopted to produce the lead pipe in recent years. However, the lead pipes produced by the two methods have certain defects, wherein the lead pipe subjected to gravity casting has an incomplete appearance and irregular size, so that the problem of acid leakage of a terminal occurs in the use process of the storage battery, while the lead pipe subjected to die casting has a regular appearance and size, but as the lead is injected into a cavity through high pressure and high speed to form a product, certain high-pressure bubbles are easily formed in the lead pipe, the phenomenon of lead splashing is generated during welding, and the phenomenon of acid permeation of the lead pipe is easily caused due to the existence of the bubbles. Therefore, the production of lead tubes still requires the introduction of new process technologies.
At present, the cold extrusion process is mature gradually and is mainly applied to the production fields of fasteners, machinery, instruments, electrical appliances, light industry, space navigation, ships, military and the like, and compared with the common casting and die-casting processes, the cold extrusion process has the characteristics of saving raw materials, improving the utilization rate of materials, reducing the finishing amount of parts and the like. However, the lead alloy has particularity relative to the above fields, so that the cold extrusion process for preparing the lead pipe of the storage battery is a new thing, and the cold extrusion part can be produced only by fully searching the cold extrusion process parameters in combination with the characteristics of the lead alloy and the performance requirements of the lead pipe.
Disclosure of Invention
The invention aims to overcome the defects of the prior art and provide the lead tube of the lead-acid storage battery, the lead tube prepared by the cold extrusion process has high dimensional accuracy and good luster, and the internal quality reaches the standard of storage battery manufacturers.
The technical problem of the invention is realized by the following technical scheme:
a lead tube of a lead-acid storage battery is prepared by adopting a cold extrusion process, and comprises the following chemical components in percentage by weight: sb:2.0% -6.0%; sn:0.02% -0.3%; as:0.1 to 0.25 percent; 0 to 0.03 percent of Se; bi is less than or equal to 0.2 percent, and the balance is Pb.
A method for manufacturing a lead tube of a lead-acid storage battery comprises the following steps:
a. melting: putting the raw materials into a lead pot according to the component ratio of a lead pipe, melting the raw materials into lead liquid, and setting the temperature to be 420-460 ℃;
b. and (3) spraying a mold: uniformly spraying a release agent on the surfaces of a core and a cavity of a mold;
c. casting: scooping a proper amount of lead liquid, slowly pouring the lead liquid into the mold, opening the mold after the lead liquid is solidified, and taking out a blank of the lead pipe;
d. extruding: setting parameters of a horizontal cold chamber die casting machine, and sleeving a cast blank on a mold core of a mold for extrusion;
e. and opening the die and taking out the finished lead pipe product.
In the method for manufacturing the lead pipe of the lead-acid storage battery, the parameters of the die casting machine in the step d comprise high-pressure die locking pressure, low-pressure die locking pressure, rapid die locking pressure and slow die locking pressure.
According to the manufacturing method of the lead tube of the lead-acid storage battery, the high-pressure mold locking pressure is 70% -90% of the total pressure, the high-pressure mold locking pressure, the low-pressure mold locking pressure, the rapid mold locking pressure and the slow mold locking pressure are sequentially reduced, the pressure difference value between the adjacent two is 5% -10%, and the maximum difference value between the slow mold locking pressure and the high-pressure mold locking pressure is 20%.
In the method for manufacturing the lead tube of the lead-acid storage battery, the total pressure of the die casting machine in the step d is set to be 150 tons to 300 tons.
The invention introduces a cold extrusion process into a lead pipe for preparing a lead-acid storage battery terminal, designs process parameters aiming at the characteristics of lead alloy and the characteristic requirements of the storage battery terminal, and optimizes the parameter combination through tests to form the optimal process for producing the cold extrusion lead pipe. The produced cold extrusion lead pipe has compact internal structure, large deformation resistance and high part quality. Thereby avoiding the problems of loose internal structure of the lead pipe, air bubbles generated in baking and the like in the traditional process; the main technical performance indexes of the lead pipe completely meet the requirements of storage battery manufacturers.
Compared with the traditional casting and die-casting process, the cold-pressing lead pipe of the storage battery prepared by the cold extrusion process has ideal surface roughness and dimensional precision, wherein the precision can reach IT 7-IT 8 level, and the surface roughness can reach R0.2-R0.6; meanwhile, after the lead alloy is subjected to cold extrusion hardening, reasonable fiber distribution is formed inside the part, so that the strength of the part is far higher than that of the material, and the stress can be formed on the surface of the part by a reasonable cold extrusion process, so that the fatigue strength of the part is improved, and the integral mechanical property of the part is further improved. Meanwhile, the process method is simple and easy to operate, high in qualification rate and harmless to the environment and personnel.
Drawings
Fig. 1 is a schematic structural view of a lead pipe according to embodiment 1 of the present invention.
Detailed Description
The present invention will be described in further detail with reference to the accompanying drawings and examples.
The lead tube of the lead-acid storage battery is manufactured on a horizontal cold chamber die casting machine by adopting a cold extrusion process. The adopted raw materials are lead alloy which meets the characteristic requirements of the storage battery terminal and is suitable for a cold extrusion process, and the lead alloy comprises the following chemical components in percentage by weight: sb:2.0 to 6.0 percent; sn:0.02 to 0.3 percent; as:0.1 to 0.25 percent; 0 to 0.03 percent of Se; bi is less than or equal to 0.2 percent, and the balance is Pb.
The content and the proportion of metals in the lead alloy are suitable, wherein antimony Sb and arsenic As are mainly used for increasing the hardness of the product, and tin Sn can increase the luster of the product. When the content of antimony is lower than 2.0% and the content of arsenic is lower than 0.1%, the alloy hardness is reduced, the cold extrusion piece is easy to deform, the cost of the lead pipe is greatly increased when the content of antimony and the content of arsenic are too high, and the abrasion of a core and a cavity of a die is accelerated, so that when the content of antimony, arsenic and tin is in the interval, the hardness can reach the Vickers hardness 15 required by the work of the lead pipe, the product has good gloss, and the cost is proper. The corrosion resistance of the terminal in the lead-acid storage battery can be effectively enhanced by adding selenium Se into the lead alloy.
The process flow of the lead pipe of the lead-acid storage battery comprises the steps of melting materials, spraying a mold, casting, extruding, opening the mold and ejecting out a product, wherein the manufacturing method comprises the following steps:
a. melting: putting the raw materials into a lead pot according to the component proportion of a lead pipe, melting the raw materials into lead liquid, and setting the melting temperature to be 420-460 ℃;
b. and (3) spraying a mold: uniformly spraying a release agent on the surfaces of a mold core and a mold cavity of the mold;
c. casting: and (b) scooping a proper amount of the molten lead liquid obtained in the step (a), slowly pouring the molten lead liquid into a mold, and opening the mold to take out a blank of the lead pipe after the lead alloy liquid is solidified. The petals of the finished lead pipe are not arranged on the blank, and the blank is not directional when placed into the cavity of the die, so that the blank is convenient for an operator to operate, and the blank is prevented from being aligned with the cavity to influence the production efficiency under the condition that the petals exist in the blank.
d. Extruding: the method is characterized in that a horizontal cold chamber die casting machine is adopted, the total pressure of the die casting machine is set to be 150-300 tons, the die can be in a plurality of cavities, and the number of the cavities is one, two, three or four. Setting parameters of a die casting machine, sleeving the blank cast in the step c on a mold core of the mold, enabling the blank to be tightly attached to the movable mold plate, starting a gasoline pump, and closing the safety door for extrusion.
The parameters of the die casting machine comprise slow mode locking pressure, fast mode locking pressure, low pressure mode locking pressure and high pressure mode locking pressure.
e. Opening the mold: opening the mould after the toggle rod is reset，And opening the safety door to take out the finished lead pipe.
The parameter proportion of the die casting machine is optimized, proper combination of high-pressure mold locking pressure, low-pressure mold locking pressure, fast mold locking pressure and slow mold locking pressure is set, and the control range of the high-pressure mold locking pressure is set to be 70-90% of the total pressure (the pressure below is specific pressure). Experiments show that when the high-pressure mold locking pressure is lower than 70%, petals of a lead pipe are not full and exceed the technical standard, and the appearance quality and the smoothness of the lead pipe are obviously reduced; and when the pressure is higher than 90%, the stability of the equipment is obviously reduced, and the service life of the die is influenced. The specific value of the high-pressure mold locking pressure is set according to the quality of the mold and the quality requirement of the product, and the high-pressure mold locking pressure is reduced as much as possible on the premise that the product quality can meet the requirement. After the high-pressure mold locking pressure is determined, the other parameters are set according to the following principle: the low-pressure mold locking pressure is smaller than the high-pressure mold locking pressure, the pressure difference value between the low-pressure mold locking pressure and the high-pressure mold locking pressure is 5% -10%, the quick mold locking pressure is smaller than the low-pressure mold locking pressure, the pressure difference value between the low-pressure mold locking pressure and the quick mold locking pressure is 5% -10%, the maximum pressure difference value between the low-pressure mold locking pressure and the high-pressure mold locking pressure is 20%, reasonable pressure combination can not only produce parts meeting the technical requirements, but also can effectively protect the mold, and the stable operation of a die casting machine is ensured.
Example 1
The dimensions of the lead tube to be produced are: the wall thickness is 2.05mm, the height is 33.2mm, the height of the blank piece is 33.3mm, the weight is 43g, and the shape of the lead pipe is shown in figure 1. The chemical composition percentage of the lead alloy required by the lead pipe is as follows: 2.9 percent of Sb; 0.19% of Sn; as 0.20%; 0.02 percent of Bi and the balance of Pb.
A horizontal cold chamber die casting machine with total pressure of 150-300 tons is adopted, a die is a die with four cavities, and the pressure parameters of cold extrusion are as follows: the total pressure is set to be 300 tons, the high-pressure mold locking pressure is 75 percent, the low-pressure mold locking pressure is 70 percent, the fast mold locking pressure is 65 percent, and the slow mold locking pressure is 55 percent.
Example 2
The size of the lead pipe is as follows: the wall thickness is 2.60mm, the height is 32.7mm, the height of a blank piece is 33.3mm, and the weight is 46g. The chemical composition percentage of the lead pipe material is as follows: 2.9 percent of Sb; 0.1% of Sn; as 0.18%; 0.02 percent of Bi and the balance of Pb.
The horizontal cold chamber die casting machine is adopted, and the main cold extrusion pressure parameters are as follows: the total pressure is 200 tons, the high-pressure mold locking pressure is 90 percent, the low-pressure mold locking pressure is 85 percent, the fast mold locking pressure is 80 percent, and the slow mold locking pressure is 75 percent.
Example 3
The size of the lead pipe is 1.5.mm in wall thickness and 18.5mm in height, the height of a blank piece is 18.8mm, and the weight of the blank piece is 14.8g. The chemical composition percentage of the lead pipe material is as follows: 3.3 percent of Sb; 0.2% of Sn; as 0.11%; se:0.023 percent, 0.01 percent of Bi and the balance of Pb.
Adopt horizontal cold chamber die casting machine, main pressure parameter is: the total pressure is 190 tons, the high-pressure mold locking pressure is 70%, the low-pressure mold locking pressure is 60%, the fast mold locking pressure is 55%, and the slow mold locking pressure is 50%.
Product inspection: randomly extracting 50 lead pipes produced in 3 examples, putting the lead pipes into an oven, and baking the lead pipes in the oven at the temperature of 190-210 ℃ for 2 hours or 280 ℃ for 15 minutes, wherein no air bubbles are found. Randomly extracting 10 produced lead tubes, applying a torque of 11.8N.m to the lead tubes in the horizontal direction, and keeping the lead tubes from being broken, cracked or twisted for 10-15 s. Through the detection of a lead tube phase structure, the crystal is fine and smooth, and the internal structure is uniform and compact; the lead pipe product has regular overall dimension and does not have the defects of cold shut, air bubbles and the like. The detection result shows that the lead pipe manufactured by the method can completely meet the requirement of the production of the storage battery.
Claims (1)
1. The manufacturing method of the lead tube of the lead-acid storage battery is characterized in that the lead tube is manufactured by adopting a cold extrusion process, and the lead tube comprises the following chemical components in percentage by weight: sb:2.9 to 3.3 percent; sn:0.19 to 0.2 percent; as:0.18 to 0.20 percent; 0 to 0.03 percent of Se; bi:0.02% -0.2%; the balance being Pb;
the preparation method comprises the following steps:
a. melting: putting the raw materials into a lead pot according to the component ratio of a lead pipe, melting the raw materials into lead liquid, and setting the temperature to be 420-460 ℃;
b. and (3) spraying a mold: uniformly spraying a release agent on the surfaces of a core and a cavity of a mold;
c. casting: scooping a proper amount of lead liquid, slowly pouring the lead liquid into the mold, opening the mold after the lead liquid is solidified, and taking out a blank of the lead pipe;
d. extruding: setting parameters of a horizontal cold chamber die casting machine, wherein the parameters of the die casting machine comprise high-pressure die locking pressure, low-pressure die locking pressure, fast die locking pressure and slow die locking pressure; sleeving the cast blank on a mold core of a mold for extrusion; the total pressure of the die casting machine is set to 150-300 tons, and the die is a die with four cavities;
the high-pressure die-locking pressure is 70-90% of the pressure of the die-casting machine; the high-pressure mold locking pressure, the low-pressure mold locking pressure, the rapid mold locking pressure and the slow mold locking pressure are sequentially reduced, the pressure ratio pressure difference value of the two adjacent pressure is 5% -10%, and the maximum specific pressure difference value between the slow mold locking pressure and the high-pressure mold locking pressure is 20%;
e. and opening the die and taking out the finished lead pipe.
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| CN202110308192.2A CN113130912B (en) | 2021-03-23 | 2021-03-23 | Lead pipe of lead-acid storage battery and manufacturing method |
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| CN113130912B true CN113130912B (en) | 2022-12-27 |
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| CN115233033A (en) * | 2022-07-14 | 2022-10-25 | 铅锂智行(北京)科技有限公司 | Lead-based alloy and product thereof |
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| CN203265598U (en) * | 2013-04-27 | 2013-11-06 | 理士电池私人有限公司 | Casting die for storage battery connecting terminals |
| CN204736027U (en) * | 2015-05-27 | 2015-11-04 | 风帆股份有限公司 | Lead acid battery colds pressing lead pipe and maintains frock |
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| DE69940622D1 (en) * | 1998-10-13 | 2009-04-30 | Water Gremlin Co | Die-casting of battery terminals |
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| CN102024920A (en) * | 2010-08-03 | 2011-04-20 | 上海志达电池有限公司 | Cold pressing manufacturing method of lead ring of lead-acid storage battery |
| CN102082257B (en) * | 2010-12-22 | 2013-10-30 | 风帆股份有限公司 | Lead pipe of lead-acid battery for starting automobile and manufacturing method |
| CN203076561U (en) * | 2012-09-18 | 2013-07-24 | 深圳领威科技有限公司 | Intelligent control system for unlocking mold of cold chamber machine |
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| CN203265598U (en) * | 2013-04-27 | 2013-11-06 | 理士电池私人有限公司 | Casting die for storage battery connecting terminals |
| CN204736027U (en) * | 2015-05-27 | 2015-11-04 | 风帆股份有限公司 | Lead acid battery colds pressing lead pipe and maintains frock |
Non-Patent Citations (1)
| Title |
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| 一种铅蓄电池用高可靠性端子密封结构的研究;张旭东 等;《蓄电池》;20180630(第3期);第132-134+144页 * |
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