CN111318785A - Process for overlaying aluminum bronze on inner surface of coal mine liquid support 27SiMn oil cylinder - Google Patents
Process for overlaying aluminum bronze on inner surface of coal mine liquid support 27SiMn oil cylinder Download PDFInfo
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- CN111318785A CN111318785A CN201811540244.3A CN201811540244A CN111318785A CN 111318785 A CN111318785 A CN 111318785A CN 201811540244 A CN201811540244 A CN 201811540244A CN 111318785 A CN111318785 A CN 111318785A
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- oil cylinder
- welding
- aluminum bronze
- 27simn
- coal mine
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K9/00—Arc welding or cutting
- B23K9/16—Arc welding or cutting making use of shielding gas
- B23K9/167—Arc welding or cutting making use of shielding gas and of a non-consumable electrode
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- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
- B23K9/00—Arc welding or cutting
- B23K9/04—Welding for other purposes than joining, e.g. built-up welding
- B23K9/044—Built-up welding on three-dimensional surfaces
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23P—METAL-WORKING NOT OTHERWISE PROVIDED FOR; COMBINED OPERATIONS; UNIVERSAL MACHINE TOOLS
- B23P6/00—Restoring or reconditioning objects
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- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Physics & Mathematics (AREA)
- Plasma & Fusion (AREA)
- Pistons, Piston Rings, And Cylinders (AREA)
- Arc Welding In General (AREA)
Abstract
A technology for overlaying aluminum bronze on the inner surface of a coal mine liquid support 27SiMn oil cylinder relates to the technical field of welding. It comprises the following steps: firstly, evaluating the inner surface condition of a coal mine liquid support 27SiMn oil cylinder; step two, removing accessories and removing rust and dirt; boring a rust layer on the inner surface of the oil cylinder; and step four, adopting HK200 aluminum bronze welding wires with the diameter of 1-1.5mm as welding materials, and welding the inner surfaces of the oil cylinders except the threads through a hot wire non-melting electrode and inert gas shielded welding. After the technical scheme is adopted, the invention has the beneficial effects that: the scrapped or to-be-scrapped hydraulic support 27SiMn oil cylinder is recycled, and by using the method, the original use performance of the oil cylinder is recovered, so that the remanufacturing of the oil cylinder is realized; the welding quality is stable, the electroplating process is completely replaced, the remanufacturing effect is achieved, the production cost is greatly reduced, the production efficiency is improved, and the service life of the oil cylinder is greatly prolonged.
Description
Technical Field
The invention relates to the technical field of welding, in particular to a process for overlaying aluminum bronze on the inner surface of a coal mine liquid support 27SiMn oil cylinder.
Background
Hydraulic support's end jar is at the course of the work, and accumulates stereoplasm granule such as coal cinder easily with the stand fitting surface, arouses the fish tail, and easily thoughtlessly advances corrosive medium such as moisture, hydrogen sulfide in the hydraulic oil to lead to end jar internal surface to appear the corrosion, influence sealed effect, finally cause the lift decline, use electroplating process at present, its shortcoming is: 1. the process has high environmental pollution and serious carcinogenesis to human body; 2. easy to fall off and influence the service life.
Disclosure of Invention
The invention aims to provide a process for overlaying aluminum bronze on the inner surface of a coal mine liquid support 27SiMn oil cylinder, aiming at the defects and shortcomings of the prior art, so that the service life of the oil cylinder is prolonged, the production efficiency is improved, hot wire tungsten electrode argon arc welding is adopted, the welding protection is good, the welding quality is stable, the labor intensity is greatly reduced, and the production efficiency is improved.
In order to achieve the purpose, the invention adopts the following technical scheme: it comprises the following steps:
firstly, evaluating the inner surface condition of a coal mine liquid support 27SiMn oil cylinder;
step two, removing accessories and removing rust and dirt;
boring a rust layer on the inner surface of the oil cylinder;
and step four, adopting HK200 aluminum bronze welding wires with the diameter of 1-1.5mm as welding materials, and welding the inner surfaces of the oil cylinders except the threads through a hot wire non-melting electrode and inert gas shielded welding.
And in the fourth step, the inert gas is high-purity argon.
In the fourth step, the welding current is 240-300A, the arc voltage is 29-30V, the hot wire current is 10A, the inert gas flow is 15-25L/min, and the welding speed is 0.35-0.4 m/min.
The application of the technology for overlaying aluminum bronze on the inner surface of the coal mine liquid support 27SiMn oil cylinder comprises the following steps: the technology of overlaying aluminum bronze is applied to the cylinder barrel, and the process flow is as follows: (1) the size of the inner hole of the fine boring reaches D +1.5(+ 0.30-0),
(2) flattening the end face and trimming a chamfer; (3) the two support nests are turned to ensure the coaxiality of the support nests and the inner hole; (4) roughly turning the inner spigot to ensure that the sizes are D1+1.5，D2+ 1.5; (5) aluminum bronze melting; (6) finely boring the size of the inner hole; (7) a flat end face; (8) taking the inner hole as a reference, and repairing two nests; (9) and the surface after deposition is rough, semi-finish turning and finish turning of the inner spigot.
The aluminum bronze melting process comprises the following process flows in remanufacturing: (1) boring an inner hole, and corroding the inner hole seriously; (2) a vehicle spigot; (3) melting copper; (4) boring and turning an inner hole and a spigot.
The purity of the pure argon is 99.995%.
After the technical scheme is adopted, the invention has the beneficial effects that: the scrapped or to-be-scrapped hydraulic support 27SiMn oil cylinder is recycled, and by using the method, the original use performance of the oil cylinder is recovered, so that the remanufacturing of the oil cylinder is realized; the method has the advantages that the inert gas shielded welding is adopted, the welding protection is good, the splashing is avoided, the welding quality is stable, the electroplating process is completely replaced, the remanufacturing effect is achieved, the production cost is greatly reduced, the production efficiency is improved, and the service life of the oil cylinder is greatly prolonged.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.
FIG. 1 is a schematic view of a cylinder barrel of an embodiment of the present invention.
Detailed Description
The technical scheme is as follows:
example 1: the oil cylinder in the coal mine hydraulic support upright column is made of 27SiMn, aluminum bronze is overlaid on the inner surface of the steel, and the process level of copper layer overlaying is required to have very important influence on the internal quality of a copper layer and the bonding performance of a steel matrix; because the carbon content of 27SiMn is high, the content of alloy elements is also high. The main problems of welding are therefore to avoid weld cracks, to reduce the hardenability of the heat-affected zone, to reduce the content of diffusible hydrogen before welding and to reduce the constraining forces in the weld zone.
The process adopts the technique that the inner wall of the 27SiMn oil steel cylinder body is bead welded with aluminum bronze, and the technique comprises the following steps: the welding method is hot wire non-consumable electrode inert gas shielded welding, and the HK200 aluminum bronze welding wire with the welding material of 1.2mm is adopted, wherein the shielding gas adopted by the hot wire non-consumable electrode inert gas shielded welding is high-purity argon with the purity of 99.995%.
The welding process parameters are as follows:
the hot wire argon tungsten-arc welding is adopted, so that the welding protection is good, the welding quality is stable, the labor intensity is greatly reduced, and the production efficiency is improved.
Referring to fig. 1, example 2: the cylinder tube inner hole copper melting process is characterized in that on the basis of the original cylinder tube process, according to the thickness of a melting layer, fine boring is carried out to increase the size of an inner hole, then the inner hole is melted with aluminum bronze, and then fine machining is carried out, so that the size is finally achieved, and the requirements are met; taking a cylinder tube as an example, the process flow is as follows: 1. the size of the inner hole of the fine boring reaches D +1.5(+ 0.30-0),
2. flattening the end face and trimming a chamfer; 3. turning two support nests to ensure the coaxiality of the support nests and the inner hole; 4. roughly turning the inner spigot to ensure that the sizes are D1+1.5，D2+ 1.5; 5. melting aluminum bronze; 6. finely boring the size of the inner hole; 7. a flat end face; 8. repairing two nests by taking the inner hole as a reference; 9. and (4) performing semi-finish turning and finish turning on the inner spigot after the surface is relatively rough after deposition.
The application in remanufacturing restoration can be carried out, the remanufacturing restoration of the sealing surface of the inner surface of the cylinder barrel due to corrosion and strain is carried out by adopting a deposited aluminum bronze process, a good effect is obtained, and the process flow of the aluminum bronze melting process in remanufacturing is as follows: 1. boring an inner hole, wherein the inner hole is seriously rusted; 2. turning a spigot; 3. melting copper; 4. boring and turning inner holes and rabbets.
The technology can treat the scrapped cylinder barrel with the depth less than 1mm due to inner hole abrasion, strain, corrosion and the like. The original size precision is recovered after size repairing and strengthening treatment, and meanwhile, the comprehensive mechanical strength of the cylinder barrel is kept or slightly higher than the original numerical value.
The aluminum bronze deposited in the cylinder wall can greatly prolong the service life of the oil cylinder, can effectively shorten the overhaul period particularly in overhaul, and has the advantages of low consumption, high quality and high efficiency.
Example 3: taking a cylinder tube as an example, the cost and time for newly manufacturing a product are compared with the cost and time for repairing a cylinder tube by using a hole-in-copper melting technology:
1. new manufacturing process flow: preparing, turning, welding, heating, turning, boring and the like;
2. the cost and the time consumption are compared as shown in the following table;
by calculation it can be found that: compared with newly manufactured 1 cylinder tube, the cylinder tube repaired by the copper melting process saves the cost by 1042.48 yuan, the newly manufactured cylinder tube is used for 50.35 hours, the newly manufactured cylinder tube is used for repairing 1 cylinder tube by the copper melting for 21.83 hours, and the newly manufactured cylinder tube 1 time is 2.3 times of the newly manufactured cylinder tube 1 time. The above table shows that the new process of melting copper is reasonably utilized to effectively shorten the overhaul period, the comprehensive quality of products can be greatly improved, for oil cylinders with thicker wall thickness and occupying most of cost, when the inner holes are seriously rusted, the inner hole deposited aluminum bronze repair process can be considered, the oil cylinders repaired by the process have performance indexes which are even better than those of new products, huge social and economic benefits can be created, and the application prospect is wide.
After the technical scheme is adopted, the invention has the beneficial effects that: the scrapped or to-be-scrapped hydraulic support 27SiMn oil cylinder is recycled, and by using the method, the original use performance of the oil cylinder is recovered, so that the remanufacturing of the oil cylinder is realized; the method has the advantages that the inert gas shielded welding is adopted, the welding protection is good, the splashing is avoided, the welding quality is stable, the electroplating process is completely replaced, the remanufacturing effect is achieved, the production cost is greatly reduced, the production efficiency is improved, and the service life of the oil cylinder is greatly prolonged.
The above description is only for the purpose of illustrating the technical solutions of the present invention and not for the purpose of limiting the same, and other modifications or equivalent substitutions made by those skilled in the art to the technical solutions of the present invention should be covered within the scope of the claims of the present invention without departing from the spirit and scope of the technical solutions of the present invention.
Claims (6)
1. A technology for overlaying aluminum bronze on the inner surface of a coal mine liquid support 27SiMn oil cylinder is characterized by comprising the following steps:
firstly, evaluating the inner surface condition of a coal mine liquid support 27SiMn oil cylinder;
step two, removing accessories and removing rust and dirt;
boring a rust layer on the inner surface of the oil cylinder;
and step four, adopting HK200 aluminum bronze welding wires with the diameter of 1-1.5mm as welding materials, and welding the inner surfaces of the oil cylinders except the threads through a hot wire non-melting electrode and inert gas shielded welding.
2. The process of overlaying aluminum bronze on the inner surface of a coal mine fluid bracket 27SiMn oil cylinder according to claim 1, wherein the process comprises the following steps: and in the fourth step, the inert gas is high-purity argon.
3. The process of overlaying aluminum bronze on the inner surface of a coal mine fluid bracket 27SiMn oil cylinder according to claim 1, wherein the process comprises the following steps: in the fourth step, the welding current is 240-300A, the arc voltage is 29-30V, the hot wire current is 10A, the inert gas flow is 15-25L/min, and the welding speed is 0.35-0.4 m/min.
4. The application of the technology for overlaying aluminum bronze on the inner surface of the coal mine liquid support 27SiMn oil cylinder is characterized by comprising the following steps of: the technology of overlaying aluminum bronze is applied to the cylinder barrel, and the process flow is as follows: (1) finely boring inner holeThe size reaches D +1.5(+ 0.30-0),
(2) flattening the end face and trimming a chamfer; (3) the two support nests are turned to ensure the coaxiality of the support nests and the inner hole; (4) roughly turning the inner spigot to ensure that the sizes are D1+1.5，D2+ 1.5; (5) aluminum bronze melting; (6) finely boring the size of the inner hole; (7) a flat end face; (8) taking the inner hole as a reference, and repairing two nests; (9) and the surface after deposition is rough, semi-finish turning and finish turning of the inner spigot.
5. The application of the process for overlaying aluminum bronze on the inner surface of the coal mine liquid support 27SiMn oil cylinder according to claim 4 is characterized in that: the aluminum bronze melting process comprises the following process flows in remanufacturing: (1) boring an inner hole, and corroding the inner hole seriously; (2) a vehicle spigot; (3) melting copper; (4) boring and turning an inner hole and a spigot.
6. The process of overlaying aluminum bronze on the inner surface of a coal mine fluid bracket 27SiMn oil cylinder according to claim 2, wherein: the purity of the pure argon is 99.995%.
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| CN201811540244.3A CN111318785A (en) | 2018-12-17 | 2018-12-17 | Process for overlaying aluminum bronze on inner surface of coal mine liquid support 27SiMn oil cylinder |
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| CN201811540244.3A CN111318785A (en) | 2018-12-17 | 2018-12-17 | Process for overlaying aluminum bronze on inner surface of coal mine liquid support 27SiMn oil cylinder |
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112222754A (en) * | 2020-10-16 | 2021-01-15 | 淮南矿业(集团)有限责任公司 | Method for repairing hinged shaft hole of cutting rocker arm of coal mining machine |
| CN113070638A (en) * | 2021-03-30 | 2021-07-06 | 郑州煤矿机械集团股份有限公司 | Machining method of high-corrosion-resistance hydraulic cylinder barrel |
| CN113084502A (en) * | 2021-04-12 | 2021-07-09 | 天津中德应用技术大学 | Intelligent manufacturing production line for electric cylinder |
| CN113997019A (en) * | 2021-11-10 | 2022-02-01 | 中煤北京煤矿机械有限责任公司 | Method for adopting thickening surfacing welding on hydraulic oil cylinder |
| CN114193080A (en) * | 2021-12-29 | 2022-03-18 | 山东能源重型装备制造集团有限责任公司 | Method for repairing cylinder bottom valve hole in stand column |
| CN114799762A (en) * | 2022-05-12 | 2022-07-29 | 河南中原特钢装备制造有限公司 | Machining process of secondary cylinder body with excircle laser-cladding inner hole for copper melting |
| CN114799426A (en) * | 2022-04-06 | 2022-07-29 | 天津市英源焊接技术有限公司 | Process for surfacing copper alloy on inner surface of coal mine liquid support 27SiMn stand column |
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Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112222754A (en) * | 2020-10-16 | 2021-01-15 | 淮南矿业(集团)有限责任公司 | Method for repairing hinged shaft hole of cutting rocker arm of coal mining machine |
| CN113070638A (en) * | 2021-03-30 | 2021-07-06 | 郑州煤矿机械集团股份有限公司 | Machining method of high-corrosion-resistance hydraulic cylinder barrel |
| CN113070638B (en) * | 2021-03-30 | 2022-09-27 | 郑州煤矿机械集团股份有限公司 | Machining method of high-corrosion-resistance hydraulic cylinder barrel |
| CN113084502A (en) * | 2021-04-12 | 2021-07-09 | 天津中德应用技术大学 | Intelligent manufacturing production line for electric cylinder |
| CN113084502B (en) * | 2021-04-12 | 2023-02-24 | 天津中德应用技术大学 | Intelligent manufacturing production line for electric cylinder |
| CN113997019A (en) * | 2021-11-10 | 2022-02-01 | 中煤北京煤矿机械有限责任公司 | Method for adopting thickening surfacing welding on hydraulic oil cylinder |
| CN114193080A (en) * | 2021-12-29 | 2022-03-18 | 山东能源重型装备制造集团有限责任公司 | Method for repairing cylinder bottom valve hole in stand column |
| CN114799426A (en) * | 2022-04-06 | 2022-07-29 | 天津市英源焊接技术有限公司 | Process for surfacing copper alloy on inner surface of coal mine liquid support 27SiMn stand column |
| CN114799762A (en) * | 2022-05-12 | 2022-07-29 | 河南中原特钢装备制造有限公司 | Machining process of secondary cylinder body with excircle laser-cladding inner hole for copper melting |
| CN114799762B (en) * | 2022-05-12 | 2023-05-16 | 河南中原特钢装备制造有限公司 | Machining process of secondary cylinder body with copper melting holes through excircle laser cladding |
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