CN103624216A - Manufacturing method of salt core prefabricated member of internal cooling oil chamber of piston - Google Patents
Manufacturing method of salt core prefabricated member of internal cooling oil chamber of piston Download PDFInfo
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- CN103624216A CN103624216A CN201310663936.8A CN201310663936A CN103624216A CN 103624216 A CN103624216 A CN 103624216A CN 201310663936 A CN201310663936 A CN 201310663936A CN 103624216 A CN103624216 A CN 103624216A
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- copper pipe
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- cooling oil
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Abstract
A manufacturing method of a salt core prefabricated member of an internal cooling oil chamber of a piston is characterized by comprising the following steps of: (1) pouring salt in a copper pipe, (2) performing compression deformation, (3) performing bending forming, (4) performing welding forming, (5) pouring fused salt, (6) drying, and (7) after drying, removing a surface scale from a blank and obtaining a prefabricated member finish product. Compared with the prior art, the method has the advantages that the method overcomes the defect that the strength and surface quality of the conventional soluble salt core cannot meet pressure of an extrusion casting technology; the high-strength salt core prefabricated member of the internal cooling oil chamber of the piston, manufactured by the method, can completely meet 100-150MPa pressure of extrusion casting; and the surface of the internal cooling oil chamber of the piston formed by the extrusion casting is smooth.
Description
Technical field
The present invention relates to a kind of preparation method of piston inner-cooling oil recess salt core prefabricated component.Belong to materials processing technology field.
Background technology
Overwhelming majority Large-power High-Speed diesel engine using integral-casting aluminum piston, in order to improve the serviceability of piston, take into account the intensity, weight of piston, wear-resisting, carrying, high-temperature behavior and cost, conventionally at the first ring groove location castingin high nickel cast iron edge circle of piston, at top, the common employing soluble salt core of thick large part technology manufacture cooling oil chamber carries out cooling to piston.At present, high-power engine piston still be take traditional gravity foundry technology as main both at home and abroad, and the inner-cooling oil recess of top land generally adopts soluble salt core to be shaped.
Squeeze cast form method is by being full of under pressure casting mold in liquid or semi-solid melt, solidifies the casting technique with crystallization.Be characterized in forming parts and process of setting, casting mold pressures partially or drift be in removable state, makes part crystallization produce certain distortion under pressure, obtains the tissue of tiny densification and higher mechanical property.
Fiber reinforced aluminum matrix composites piston adopts Extrution casting technique manufacture, dense structure, and material property approaches forging level.First piston ring groove adopts aluminum matrix composite to substitute high nickel cast iron, and piston overall weight alleviates, and wearability and high nickel cast iron are suitable, improves more than five times with alloy matrix aluminum bond strength; Moulding process adopts advanced Extrution casting technique to substitute traditional gravity foundry technology, and the high-temperature behavior of piston, heat-resistant anti-fatigue performance and heat endurance index are all better than metal mold gravity casting piston, and the dependability of piston is improved.
Because conventional soluble salt core intensity and surface quality are difficult to bear Extrution casting technique pressure, with the cooling oil duct of soluble salt core method extrusion casint piston, can not meet the demands.Certainly will need technical staff to develop a kind of novel prefabricated component manufacture method.
Summary of the invention
Technical problem to be solved by this invention is that a kind of manufacture method of high-intensity piston inner-cooling oil recess salt core prefabricated component is provided for the above-mentioned state of the art.
The present invention solves the problems of the technologies described above adopted technical scheme: a kind of manufacture method of piston inner-cooling oil recess salt core prefabricated component, is characterized in that comprising the steps:
1. copper pipe is filled with salt: industrial refined salt is dried, the industrial refined salt of drying caking is pulverized, pour in copper pipe, after consolidation, copper pipe two is struck flat;
2. compacting distortion: will fill with copper pipe crimp in extrusion die of salt, pressure 150MPa～200MPa, pressurize 15s～30s, after release, obtains the copper pipe of inner-cooling oil recess cross sectional shape;
3. bend shaping: by filling with salt copper pipe, be contained on round as a ball mould, copper pipe is heated, 450 ℃～500 ℃ of heating-up temperatures, are bent into copper pipe spiral-shaped;
4. welding forming: the copper pipe after bending is cut off, two ends form otch, remove the industrial refined salt of copper pipe inside, adopt argon arc welding welding otch and arm, and at the end of arm argon arc welding and cup, the inner chamber after welding is passed into compressed air, pressure 0.2MPa～0.5MPa, and be immersed in the water, continue 1min～-2min and occur without bubble;
5. pour into fused salt: industrial refined salt is joined to heat fused in Medium Frequency Induction Heating Furnace, 820 ℃～880 ℃ heat preservation for standby use, will weld copper pipe and be placed on fire door preheating, after preheating, immerse in fused salt, fill the saline solution of melting, keep flat cool to room temperature;
6. dry: excision cup, the salt slag of removing copper pipe surface, the burr at polishing copper pipe arm place, the blank of formation inner-cooling oil recess salt core prefabricated component, dries;
7. after drying, blank is removed to surface scale, obtain prefabricated component finished product.
As preferably, step 1. described copper pipe is fine copper, or is Kufil, weight of copper percentage >=99.9% in this Kufil.
As preferably, step is 100 ℃～120 ℃ of described bake out temperatures 1., and temperature retention time 9h～10h.
As preferably, step is 5. described to be welded copper pipe to be placed on fire door preheating time is 4min～5min.
As preferably, the drying condition of step described in is 6. as follows: blank is packed in baking oven into 150 ℃～200 ℃ of oven temperatures, drying time 8h～10h.
The method of copper pipe composite core, is about to copper pipe and is bent into the shape of piston inner-cooling oil recess, and in copper pipe, fill the saline solution of melting, improves the pressure of its anti-extrusion deformation.Copper pipe prefabricated component is cast into the interior oil cooling passage of shaping in piston, and the salt water of filling in copper pipe dissolves, and copper pipe is removed with chemical corrosion method.This technique manufacturing process is simple, low cost of manufacture, and anti-extrusion deformation ability is strong, and the recyclable recycling of copper pipe, can meet production in enormous quantities needs completely.
Compared with prior art, the invention has the advantages that:
1, the intensity of conventional soluble salt core and the shortcoming that surface quality can not meet Extrution casting technique pressure have been overcome, adopt the pressure that high strength piston inner-cooling oil recess salt core prefabricated component that the present invention manufactures completely can extrusion casint 100MPa-150MPa, the piston inner-cooling oil recess smooth surface that extrusion casint forms.
2, manufacturing process of the present invention is simple, low cost of manufacture, and the piston inner-cooling oil recess salt core prefabricated component of manufacture has high-intensity anti-extrusion deformation ability.
Accompanying drawing explanation
Fig. 1 is the flow chart of embodiment 1.
Fig. 2 is the structural representation of piston inner-cooling oil recess prefabricated component copper pipe compacting distortion in embodiment 1.
Fig. 3 is piston inner-cooling oil recess prefabricated component copper pipe bending structure schematic diagram in embodiment 1.
Fig. 4 is that the piston inner-cooling oil recess prefabricated component of moulding in embodiment 1 is filled with salt pre-structure schematic diagram.
Fig. 5 is piston inner-cooling oil recess salt core prefabricated component finished product structure schematic diagram in embodiment 1.
The specific embodiment
Below in conjunction with accompanying drawing, embodiment is described in further detail the present invention.
Embodiment 1: shown in Fig. 1～Fig. 5, the manufacture method preparation process of the piston inner-cooling oil recess salt core prefabricated component in the present embodiment is as follows:
1. copper pipe is filled with salt: industrial refined salt 1 is dried, and 100 ℃ of bake out temperatures, temperature retention time 9h, pulverizes the industrial refined salt 1 of drying caking, pours in copper pipe 2, after consolidation, copper pipe 2 two is struck flat;
2. compacting distortion: will fill with copper pipe crimp in extrusion die 3 of salt, pressure 150MPa, pressurize 15s, after release, obtains the copper pipe 2a of cold oil chamber cross sectional shape;
3. bend shaping: by filling with salt copper pipe 2a, be contained on round as a ball mould 5,2a heats to copper pipe, and 450 ℃ of heating-up temperatures, are bent into spiral-shaped 4 by copper pipe 2a;
4. welding forming: the copper pipe 2a after bending is cut off, remove the industrial refined salt 1 of copper pipe 2a inside, adopt argon arc welding welding otch, arm 6 and cup 7, inner chamber after welding is passed into compressed air, pressure 0.2MPa, and be immersed in the water, continue 1min and occur without bubble;
5. pour into fused salt: industrial refined salt 1 is joined to heat fused in Medium Frequency Induction Heating Furnace, 820 ℃ of heat preservation for standby use.The copper pipe that welds arm 6 and cup 7 is placed on to fire door preheating 4min, immerses in fused salt, fill the saline solution of melting, keep flat cool to room temperature;
6. dry: excision cup, the salt slag of removing copper pipe surface, the burr at polishing copper pipe arm place, forms inner-cooling oil recess salt core prefabricated component 8, inner-cooling oil recess salt core prefabricated component 8 is packed in baking oven into 150 ℃ of oven temperatures, drying time 8h;
7. after baking, remove surface scale, obtain high strength piston inner-cooling oil recess salt core prefabricated component 8 finished products;
Resulting high strength piston inner-cooling oil recess salt core prefabricated component in the present embodiment, anti-extrusion deformation ability is strong, can meet the piston Extrution casting technique of 100MPa～150MPa pressure completely, internal piston dense structure, piston inner-cooling oil recess is smooth, without casting flaw; Manufacturing process of the present invention is simple, low cost of manufacture, and piston dependability significantly strengthens.
Embodiment 2:
1. copper pipe is filled with salt: industrial refined salt is dried, and 110 ℃ of bake out temperatures, temperature retention time 9.5h, pulverizes the industrial refined salt of drying caking, pours in copper pipe, after consolidation, copper pipe two is struck flat;
2. compacting distortion: will fill with copper pipe crimp in extrusion die of salt, pressure 180MPa, pressurize 20s, after release, obtains the copper pipe of cold oil chamber cross sectional shape;
3. bend shaping: by filling with salt copper pipe, be contained on round as a ball mould, copper pipe is heated, 480 ℃ of heating-up temperatures, are bent into copper pipe spiral-shaped;
4. welding forming: the copper pipe after bending is cut off, remove the industrial refined salt of copper pipe inside, adopt argon arc welding welding otch, arm and cup, the inner chamber after welding is passed into compressed air, pressure 0.4MPa, and be immersed in the water, continue 1.5min and occur without bubble;
5. pour into fused salt: industrial refined salt 1 is joined to heat fused in Medium Frequency Induction Heating Furnace, 850 ℃ of heat preservation for standby use.The copper pipe that welds arm and cup is placed on to fire door preheating 4.5min, immerses in fused salt, fill the saline solution of melting, keep flat cool to room temperature;
6. dry: excision cup, the salt slag of removing copper pipe surface, the burr at polishing copper pipe arm place, forms inner-cooling oil recess salt core prefabricated component, inner-cooling oil recess salt core prefabricated component is packed in baking oven into 180 ℃ of oven temperatures, drying time 9h;
7. after baking, remove surface scale, obtain high strength piston inner-cooling oil recess salt core prefabricated component finished product;
Resulting high strength piston inner-cooling oil recess salt core prefabricated component in the present embodiment, anti-extrusion deformation ability is strong, can meet the piston Extrution casting technique of 100MPa～150MPa pressure completely, internal piston dense structure, piston inner-cooling oil recess is smooth, without casting flaw; Manufacturing process of the present invention is simple, low cost of manufacture, and piston dependability significantly strengthens.
Embodiment 3:
1. copper pipe is filled with salt: industrial refined salt is dried, and 120 ℃ of bake out temperatures, temperature retention time 10h, pulverizes the industrial refined salt of drying caking, pours in copper pipe, after consolidation, copper pipe two is struck flat.
2. compacting distortion: will fill with copper pipe crimp in extrusion die of salt, pressure 200MPa, pressurize 30s, after release, obtains copper pipe inner-cooling oil recess cross sectional shape.
3. bend shaping: by filling with salt copper pipe, be contained on round as a ball mould, copper pipe is heated, 500 ℃ of heating-up temperatures, are bent into copper pipe spiral-shaped.
4. welding forming: the copper pipe after bending is cut off, remove the industrial refined salt of copper pipe inside, adopt argon arc welding welding otch, arm and cup, the inner chamber after welding is passed into compressed air, pressure 0.5MPa, and be immersed in the water, continue 2min and occur without bubble.
5. pour into fused salt: industrial refined salt 1 is joined to heat fused in Medium Frequency Induction Heating Furnace, 880 ℃ of heat preservation for standby use.The copper pipe that welds arm and cup is placed on to fire door preheating 5min, immerses in fused salt, fill the saline solution of melting, keep flat cool to room temperature.
6. dry: excision cup, the salt slag of removing copper pipe surface, the burr at polishing copper pipe arm place, forms inner-cooling oil recess salt core prefabricated component, inner-cooling oil recess salt core prefabricated component is packed in baking oven into 200 ℃ of oven temperatures, drying time 10h;
7. after baking, remove surface scale, obtain high strength piston inner-cooling oil recess salt core prefabricated component finished product;
Resulting high strength piston inner-cooling oil recess salt core prefabricated component in the present embodiment, anti-extrusion deformation ability is strong, can meet the piston Extrution casting technique of 100MPa～150MPa pressure completely, internal piston dense structure, piston inner-cooling oil recess is smooth, without casting flaw; Manufacturing process of the present invention is simple, low cost of manufacture, and piston dependability significantly strengthens.
Claims (5)
1. a manufacture method for piston inner-cooling oil recess salt core prefabricated component, is characterized in that comprising the steps:
1. copper pipe is filled with salt: industrial refined salt is dried, the industrial refined salt of drying caking is pulverized, pour in copper pipe, after consolidation, copper pipe two is struck flat;
2. compacting distortion: will fill with copper pipe crimp in extrusion die of salt, pressure 150MPa～200MPa, pressurize 15s～30s, after release, obtains the copper pipe of inner-cooling oil recess cross sectional shape;
3. bend shaping: by filling with salt copper pipe, be contained on round as a ball mould, copper pipe is heated, 450 ℃～500 ℃ of heating-up temperatures, are bent into copper pipe spiral-shaped;
4. welding forming: the copper pipe after bending is cut off, two ends form otch, remove the industrial refined salt of copper pipe inside, adopt argon arc welding welding otch and arm, and at the end of arm argon arc welding and cup, the inner chamber after welding is passed into compressed air, pressure 0.2MPa～0.5MPa, and be immersed in the water, continue 1min～-2min and occur without bubble;
5. pour into fused salt: industrial refined salt is joined to heat fused in Medium Frequency Induction Heating Furnace, 820 ℃～880 ℃ heat preservation for standby use, will weld copper pipe and be placed on fire door preheating, after preheating, immerse in fused salt, fill the saline solution of melting, keep flat cool to room temperature;
6. dry: excision cup, the salt slag of removing copper pipe surface, the burr at polishing copper pipe arm place, the blank of formation inner-cooling oil recess salt core prefabricated component, dries;
7. after drying, blank is removed to surface scale, obtain prefabricated component finished product.
2. the manufacture method of piston inner-cooling oil recess salt core prefabricated component according to claim 1, is characterized in that the copper pipe described in step is 1. fine copper, or is Kufil, weight of copper percentage >=99.9% in this Kufil.
3. the manufacture method of piston inner-cooling oil recess salt core prefabricated component according to claim 1, is characterized in that 1. 100 ℃～120 ℃ of described bake out temperatures of step, and temperature retention time 9h～10h.
4. the manufacture method of piston inner-cooling oil recess salt core prefabricated component according to claim 1, is characterized in that be 4min～5min the preheating time described in step 5..
5. the manufacture method of piston inner-cooling oil recess salt core prefabricated component according to claim 1, is characterized in that the drying condition described in step is 6. as follows: blank is packed in baking oven into 150 ℃～200 ℃ of oven temperatures, drying time 8h～10h.
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| CN201310663936.8A CN103624216B (en) | 2013-12-09 | 2013-12-09 | The manufacture method of piston inner-cooling oil recess salt core prefabricated component |
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| CN201310663936.8A CN103624216B (en) | 2013-12-09 | 2013-12-09 | The manufacture method of piston inner-cooling oil recess salt core prefabricated component |
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| CN103624216B CN103624216B (en) | 2016-05-25 |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN108655362A (en) * | 2017-03-30 | 2018-10-16 | 现代自动车株式会社 | Hollow salt core and preparation method thereof |
| CN108788020A (en) * | 2018-06-13 | 2018-11-13 | 滨州东海龙活塞有限公司 | A kind of production method of interior oil cooling passage salt core |
| CN110576074A (en) * | 2019-08-19 | 2019-12-17 | 河北欧姆隆机械有限公司 | manufacturing process of flattened bent pipe |
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Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108655362A (en) * | 2017-03-30 | 2018-10-16 | 现代自动车株式会社 | Hollow salt core and preparation method thereof |
| CN108788020A (en) * | 2018-06-13 | 2018-11-13 | 滨州东海龙活塞有限公司 | A kind of production method of interior oil cooling passage salt core |
| CN108788020B (en) * | 2018-06-13 | 2019-10-18 | 滨州东海龙活塞有限公司 | A kind of production method of interior oil cooling passage salt core |
| CN110576074A (en) * | 2019-08-19 | 2019-12-17 | 河北欧姆隆机械有限公司 | manufacturing process of flattened bent pipe |
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