Forming machining process for high-precision automobile cylinder cover casting

Abstract

The invention discloses a high-precision automobile cylinder cover casting forming processing technology, and relates to the technical field of automobile part processing, and the high-precision automobile cylinder cover casting forming processing technology comprises the following steps: S1, material processing; s2, preparing a mold; s3, milling machine machining is conducted, specifically, a milling machine is used for conducting turn-milling machining on the top, the bottom and the periphery of the die-cast cylinder cover; mounting a special fixture for the cylinder cover on the milling machine to perform finish machining on the casting; and S4, quality detection is conducted, specifically, after the cylinder cover is poured, the size and all hole sites of the cylinder cover are detected in advance, the mold is abandoned when the size is detected to be unqualified, the next procedure is conducted after the size is qualified, and final detection is conducted again after the cylinder cover is machined. The production quality is improved, resources are saved, economical efficiency is improved, the production requirements of people are met, the machining procedure is shortened, and under the combined action of die abandoning when size detection is unqualified, entering the next procedure after the size detection is qualified and final inspection is conducted again after cylinder cover machining is completed, unqualified parts can be found in time, and waste is avoided.

Description

Technical Field

[0001] The invention relates to the technical field of automobile parts processing, and in particular to a high-precision automobile cylinder head casting molding processing technology. Background Art

[0002] Cars are the most common and commonly used means of transportation in modern society, which brings a lot of convenience to our production and life. Especially in recent years, with the rapid development of the automobile industry, the style and performance of cars have been greatly improved, thus attracting the attention of many car buyers. Then to maintain this long-lasting momentum, one of the key links is to continuously improve the processing technology to make the product more practical, economical and beautiful. The overall structure of a common car is composed of four parts: engine, chassis, electrical equipment and body. The engine is the power unit of the car, and the chassis is used to transmit the power generated by the engine. The electrical equipment includes the power supply part, engine ignition and lighting and other electrical equipment. The body is used to accommodate the driver, passengers or cargo. The gasoline engine mainly consists of cylinders, cylinder heads, connecting rods and crankshafts, intake valves, exhaust valves, spark plugs and other parts. The cylinder head forms a sealed combustion chamber, where the fuel burns, generating gas expansion, pushing the piston downward, and transmitting the force to the crankshaft through the connecting rod, so that the crankshaft rotates to output power. The intake valve controls the entry of the combustible mixture, while the exhaust valve controls the exhaust of the exhaust gas. The main function of the cylinder head is to seal the cylinder block and the upper plane of the cylinder liner together with the cylinder seal, and to form a combustion chamber together with the piston top and the cylinder wall. There is a cooling water jacket inside the cylinder head, and the cooling water holes on the lower end surface are connected to the cooling water holes of the cylinder block, so that circulating water can be used to cool the high-temperature parts such as the combustion chamber.

[0003] Existing automobile cylinder head castings have poor rigidity and are easily deformed during use. The poor processing technology affects the production quality of the cylinder head, and innovative development in the field of cylinder head processing is needed.

[0004] In order to solve the problems existing in the prior art, the present invention provides a high-precision automobile cylinder head casting molding process. Summary of the invention

[0005] In order to solve the above technical problems, the technical solution adopted by the present invention is: A high-precision automobile cylinder head casting molding process includes the following processes: S1. Material processing: The aluminum ingot material to be processed is melted and processed. The aluminum ingot material is melted in a melting and holding furnace. The heating temperature of the melting and holding furnace is 800°C. S2. preparing a mold: pressing a mold of the same shape and size as the cylinder head into clay to obtain a sand mold of the cylinder head mold, and pouring the cooled aluminum solution into the sand mold of the cylinder head mold for die casting; S3, milling machine processing: use the milling machine to turn and mill the top, bottom and surrounding of the die-cast cylinder head respectively; install the cylinder head special fixture on the milling machine to perform fine processing on the casting; S4. Quality inspection: After the cylinder head is cast, the size and each hole position of the cylinder head are inspected in advance. If the size inspection fails, the mold will be scrapped. If it passes, it will enter the next process. After the cylinder head is processed, the final inspection will be carried out again.

[0006] A further improvement of the technical solution of the present invention is that after all the S1 aluminum ingots are melted to obtain aluminum solution, the temperature of the aluminum solution is waited to drop to 750°C. After the temperature drops to the specified temperature, a refining agent is added to the solution for refining processing. The refining process is to uniformly stir the solution for 10 minutes.

[0007] The further improvement of the technical solution of the present invention is that the main components of the refining agent are oxidant, deoxidant, alloying agent and adjusting agent, the oxidant is used to oxidize impurities and form slag, the oxidant is pure oxygen and iron ore, the deoxidizer removes oxygen in aluminum, and the deoxidizer is aluminum and silicon metal oxides.

[0008] The technical solution of the present invention is further improved in that the ratio of the amount of the refining agent to the aluminum solution is 1:600, and the specific amount of addition is determined according to the weight of the aluminum liquid in the insulation furnace. After the aluminum liquid is refined, a slag remover is added to the aluminum liquid for the next process. The slag remover comprises 25-45 sodium chloride, 30-50 potassium chloride, 3-7 calcium fluoride, and 1-6 aluminum chloride. The slag remover removes impurities in the metal liquid, makes the slag loose and easy to remove through chemical reactions, improves the purity of the aluminum liquid, and improves the quality of the metal. After the slag removal is completed, the temperature of the aluminum liquid is adjusted to the pouring temperature for die casting.

[0009] A further improvement of the technical solution of the present invention is that: S2 uses the prepared cylinder head sand mold for die casting, preheats the sand mold before die casting, pours the prepared aluminum liquid into the mold and then closes the mold, evacuates the air after the mold is closed, uses the slag bag to lead out several air grooves, connects the customized exhaust plate and the synchronous stop valve, and then connects to the vacuum pipe of the vacuum system. The vacuum system moves to the injection port of the material pipe after the mold closing is confirmed according to the working order of the die casting machine, forming a closed state between the mold cavity and the material pipe. The valve on the output pipe of the gas tank of the vacuum system is opened to perform vacuuming. The injection is stopped after fast injection and pressurization, and the valve of the vacuum system is closed to stop vacuuming, reduce the bubble rate, and improve the quality of the casting. The vacuuming duration is 3 seconds, the pouring temperature is 660, and the injection time is 5 seconds.

[0010] A further improvement of the technical solution of the present invention is that after the vacuum is completed, the formed casting is subjected to a secondary pressurization treatment, and the secondary pressurization time is 8 seconds. After the secondary pressurization work is completed, the mold air top blowing is started. During the blowing, the mold is fixed in the working area, and the cylinder is connected to the blowing pipe on the mold to ensure that the cylinder and the blowing pipe are tight and leak-free. The air pressure of the cylinder is adjusted according to actual conditions to control the air flow in the blowing pipe. When the air pressure is adjusted, the cylinder can be started to make the air flow flow out of the blowing pipe, lift the mold, and blow out the debris sucked into the pipe during vacuuming.

[0011] A further improvement of the technical solution of the present invention is that before the S3 milling machine is used for pressing, a hydraulic press is used to trim the castings after die casting to recover waste materials, and then a sanding machine is used to grind the excess scraps. The milling sequence of the cylinder head is top and bottom planes, transition positioning reference processing, main positioning reference processing, front and rear end faces and two side surfaces processing, general hole system processing of each surface, fine milling of the bottom surface, conduit valve seat bottom hole and fine processing. The bottom plane is fine milled once before the valve seat conduit bottom hole fine processing process. If the reference locating pin is obviously worn after repeated positioning use, consider arranging two sets of locating pins or re-fine reaming the original locating pins.

[0012] A further improvement of the technical solution of the present invention is that after the S4 quality inspection is qualified, the products are packaged and put into storage, and anti-rust, moisture-proof and dust-proof measures are taken during packaging.

[0013] Due to the adoption of the above technical solution, the present invention has the following technical advances compared with the prior art: The invention provides a high-precision automobile cylinder head casting molding processing technology. After the air is exhausted, the molded casting is subjected to a secondary pressurization treatment. A vacuum treatment is first performed to remove the gas in the cavity, reduce the bubble rate, and reduce the back pressure in the cavity at the same time. An alloy with a lower specific pressure and poor casting performance can be used for die casting and then subjected to a local secondary pressurization treatment, so that the local strength of the casting is improved, the air tightness of the casting is improved, the shrinkage cavities are reduced, the hardness is increased, the structure is refined, and the plating performance is improved, the production quality is improved, resources are saved, the economy is improved, people's production needs are met, the processing steps are shortened, and the superposition error caused by multiple clamping processes is avoided.

[0014] The present invention provides a high-precision automobile cylinder head casting forming processing technology. After the cylinder head is cast, the size and each hole position of the cylinder head are pre-detected. If the size detection fails, the mold is scrapped. If it passes, it enters the next process. After the cylinder head is processed, a final inspection is performed again, so that unqualified parts can be found in time to avoid waste caused by further processing, so that the performance of the alloy liquid is more stable and the die-casting effect is better. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1It is a schematic diagram of the process flow of the high-precision automobile cylinder head casting molding process of the present invention; Figure 2 It is a structural schematic diagram of the material processing flow of the present invention. DETAILED DESCRIPTION

[0016] The present invention is further described in detail below in conjunction with embodiments: like Figure 1-2 As shown, the present invention provides a high-precision automobile cylinder head casting molding process, including the following process: S1. Material processing: The aluminum ingot materials used for processing are dissolved and processed. The aluminum ingot material is dissolved in a melting and holding furnace. The heating temperature of the melting and holding furnace is 800°C. After all the aluminum ingots are melted to obtain aluminum solution, the temperature of the aluminum solution is waited to drop to 750°C. After the temperature drops to the specified temperature, a refining agent is added to the solution for refining processing. The refining process is to stir the solution evenly for 10 minutes. The main components of the refining agent are oxidant, deoxidizer, alloying agent and adjusting agent. The oxidant is used to oxidize impurities and form slag. The oxidant is pure oxygen and iron ore. The deoxidizer removes aluminum. The oxygen in the molten aluminum is removed by the deoxidizer, which is aluminum and silicon metal oxides. The ratio of the amount of the refining agent to the aluminum solution is 1:600. The specific amount of addition depends on the weight of the aluminum liquid in the holding furnace. After the aluminum liquid is refined, a slag remover is added to the aluminum liquid for the next process. The slag remover is composed of 25-45 sodium chloride, 30-50 potassium chloride, 3-7 calcium fluoride, and 1-6 aluminum chloride. The slag remover removes impurities in the molten metal and makes the slag loose and easy to remove through chemical reactions, thereby improving the purity of the aluminum liquid and the quality of the metal. After the slag removal is completed, the temperature of the aluminum liquid is adjusted to the pouring temperature for die casting; S2. Prepare the mold: press a mold of the same shape and size as the cylinder head into clay to obtain a sand mold of the cylinder head mold, pour the cooled aluminum solution into the sand mold of the cylinder head mold for die-casting, use the prepared sand mold of the cylinder head for die-casting, preheat the sand mold before die-casting, pour the prepared aluminum solution into the mold and then close the mold, evacuate the air after closing the mold, use the slag bag to lead out several air grooves, connect the customized exhaust plate and the synchronous stop valve, and then connect the vacuum system's vacuum pipeline. After the vacuum system is confirmed according to the working order of the die-casting machine, it moves to the injection port of the material pipe to form a closed state between the mold cavity and the material pipe, and the valve on the output pipeline of the vacuum system's gas tank is opened to perform vacuuming, and the injection is fast and the injection is completed. After the pressurization is completed, stop and close the valve of the vacuum system, stop pumping, reduce the bubble rate, and improve the quality of the casting. The vacuuming duration is 3 seconds, the pouring temperature is 660, and the injection time is 5 seconds. After the vacuuming is completed, the molded casting is subjected to secondary pressurization treatment. The secondary pressurization time is 8 seconds. After the secondary pressurization work is completed, start the mold air top blowing. When blowing, fix the mold in the working area, connect the cylinder with the blowing pipe on the mold, and ensure that the cylinder and the blowing pipe are tight and leak-free. Adjust the air pressure of the cylinder according to the actual situation to control the air flow in the blowing pipe. When the air pressure is adjusted, start the cylinder to make the air flow flow out of the blowing pipe, lift the mold, and blow out the debris sucked into the pipe during the vacuuming. S3, milling machine processing: use the milling machine to turn and mill the top, bottom and surrounding of the die-cast cylinder head respectively; install the cylinder head special fixture on the milling machine to perform fine processing on the casting. Before the milling machine processing, use the hydraulic press to trim the die-cast casting to recover the waste, and then use the sanding machine to grind the excess scraps. The milling sequence of the cylinder head is the top and bottom planes, transition positioning reference processing, main positioning reference processing, front and rear end faces and two side surfaces processing, general hole system processing of each surface, fine milling of the bottom surface, guide valve seat bottom hole and fine processing. Before the valve seat guide bottom hole fine processing process, the bottom plane is fine milled once. If the reference positioning pin is obviously worn after repeated positioning, consider arranging two sets of positioning pins or re-finishing the original positioning pins; S4. Quality inspection: After the cylinder head is cast, the size and each hole position of the cylinder head are pre-inspected. If the size inspection fails, the mold will be scrapped. If it passes, it will enter the next process. After the cylinder head is processed, the final inspection will be carried out again; after passing the quality inspection, it will be packaged and put into storage. Pay attention to anti-rust, moisture-proof and dust-proof measures during packaging.

[0017] The following is a detailed description of the working principle of the high-precision automobile cylinder head casting molding process.

[0018] like Figure 1-2As shown, the aluminum ingot material for processing is dissolved and processed. The aluminum ingot material is dissolved in a melting and holding furnace. The heating temperature of the melting and holding furnace is 800°C. After the aluminum ingots are completely melted to obtain an aluminum solution, the temperature of the aluminum solution is waited to drop to 750°C. After the temperature drops to the specified temperature, a refining agent is added to the solution for refining processing. The refining process is to stir the solution evenly for 10 minutes. The main components of the refining agent are an oxidant, a deoxidizer, an alloying agent and a regulator. The oxidant is used to oxidize impurities and form slag. The oxidant is pure oxygen and iron ore. The deoxidizer removes impurities in the aluminum. Oxygen, the deoxidizer is aluminum and silicon metal oxides, the ratio of the amount of refining agent to the aluminum solution is 1:600, and the specific amount of addition depends on the weight of the aluminum liquid in the holding furnace. After the aluminum liquid is refined, a slag remover is added to the aluminum liquid for the next process. The slag remover composition is 25-45 sodium chloride, 30-50 potassium chloride, 3-7 calcium fluoride, and 1-6 aluminum chloride. The slag remover removes impurities in the metal liquid and makes the slag loose and easy to remove through chemical reactions, thereby improving the purity of the aluminum liquid and the quality of the metal. After the slag removal is completed, the temperature of the aluminum liquid is adjusted to the pouring temperature for die casting.A mold of the same shape and size as the cylinder head is pressed into clay to obtain a sand mold of the cylinder head mold, and the cooled aluminum solution is poured into the sand mold of the cylinder head mold for die casting. The prepared cylinder head sand mold is used for die casting. The sand mold is preheated before die casting, and the prepared aluminum liquid is poured into the mold and then the mold is closed. After the mold is closed, air is pumped, and several air grooves are led out by using a slag bag, and a customized exhaust plate and a synchronous shut-off valve are connected, and then connected to the vacuum pumping pipeline of the vacuum system. The vacuum system follows the working sequence of the die casting machine. After the mold closing is confirmed, when it moves to the injection port of the material pipe, a closed state is formed between the mold cavity and the material pipe. The valve on the output pipeline of the gas tank of the vacuum system is opened to perform air extraction. After the injection is completed after fast injection and pressurization, it stops and the valve of the vacuum system is closed, and air extraction is stopped to reduce the bubble rate and improve the quality of the casting. The vacuum pumping duration is 3 seconds, the pouring temperature is 660, and the injection time is 5 seconds. After the air extraction is completed, the formed casting is subjected to secondary pressurization treatment. The first pressurization time is 8 seconds. After completing the secondary pressurization work, start the mold air top blowing. When blowing, fix the mold in the working area, connect the cylinder to the blowing pipe on the mold, ensure that the cylinder and the blowing pipe are tight and leak-free, adjust the air pressure of the cylinder according to the actual situation to control the air flow in the blowing pipe. When the air pressure is adjusted, start the cylinder to make the air flow flow out of the blowing pipe, lift the mold, and blow out the debris sucked into the pipe during vacuuming. First, perform vacuum treatment to remove the gas in the cavity, reduce the bubble rate, and reduce the back pressure in the cavity. You can use alloys with lower specific pressure and poor casting performance for local secondary pressurization treatment after die casting, so that the local strength of the casting is improved, the air tightness of the casting is improved, and shrinkage holes are reduced, the hardness is increased, the organization is refined, and the plating performance is improved, which improves the production quality, saves resources, and improves the economy. It meets people's production needs, shortens the processing procedures, and avoids the superposition error caused by multiple clamping processes. Use a milling machine to turn and mill the top, bottom and surrounding areas of the die-cast cylinder head respectively; install a special clamp for the cylinder head on the milling machine to perform finish machining on the casting. Before the milling machine machining, use a hydraulic press to trim the die-cast casting to recover waste, and then use a sanding machine to grind and process excess scraps. The milling sequence of the cylinder head is top and bottom planes, transition positioning reference machining, main positioning reference machining, front and rear end faces and two side surfaces machining, general hole system machining on each surface, finish milling of the bottom surface, guide valve seat bottom hole and finish machining. Before the valve seat guide bottom hole finish machining process, the bottom plane is finish milled once. If the reference locating pin is obviously worn after repeated positioning, consider arranging two sets of locating pins or re-finishing the original locating pins.After the cylinder head is cast, the size and each hole position of the cylinder head are pre-inspected. If the size inspection fails, the mold will be scrapped. If it passes, it will enter the next process. After the cylinder head is processed, it will be subject to final inspection again. After the quality inspection is passed, it will be packaged and put into storage. When packaging, pay attention to rust-proof, moisture-proof and dust-proof measures. If the size inspection fails, the mold will be scrapped. If it passes, it will enter the next process. After the cylinder head is processed, it will be subject to final inspection again. Under the joint action, unqualified parts can be discovered in time to avoid waste caused by further processing, making the alloy liquid performance more stable and the die-casting effect better.

[0019] The above generally describes the present invention in detail, but it is obvious to a person skilled in the art that some modifications or improvements can be made to the present invention. Therefore, modifications or improvements that do not depart from the spirit of the present invention are within the scope of protection of the present invention.

Claims

1. A high-precision automobile cylinder head casting molding process, including the following process, characterized in that: S1. Material processing: The aluminum ingot material to be processed is melted and processed. The aluminum ingot material is melted in a melting and holding furnace. The heating temperature of the melting and holding furnace is 800°C. S2. preparing a mold: pressing a mold of the same shape and size as the cylinder head into clay to obtain a sand mold of the cylinder head mold, and pouring the cooled aluminum solution into the sand mold of the cylinder head mold for die casting; S3, milling machine processing: use the milling machine to turn and mill the top, bottom and surrounding of the die-cast cylinder head respectively; install the cylinder head special fixture on the milling machine to perform fine processing on the casting; S4. Quality inspection: After the cylinder head is cast, the size and each hole position of the cylinder head are inspected in advance. If the size inspection fails, the mold will be scrapped. If it passes, it will enter the next process. After the cylinder head is processed, the final inspection will be carried out again.

2. The high-precision automobile cylinder head casting molding process according to claim 1 is characterized in that: After all the S1 aluminum ingots are melted to obtain aluminum solution, wait for the temperature of the aluminum solution to drop to 750°C. After the temperature drops to the specified temperature, refining agent is added to the solution for refining processing. The refining process is to evenly stir the solution for 10 minutes.

3. A high-precision automobile cylinder head casting molding process according to claim 2, characterized in that: The main components of refining agents are oxidants, deoxidizers, alloying agents and adjusters. The oxidizer is used to oxidize impurities and form slag. The oxidizer is pure oxygen and iron ore. The deoxidizer removes oxygen from aluminum. The deoxidizer is aluminum and silicon metal oxides.

4. The high-precision automobile cylinder head casting molding process according to claim 3 is characterized in that: The ratio of the amount of refining agent to the aluminum solution is 1:

600. The specific amount of addition depends on the weight of the aluminum liquid in the holding furnace. After the aluminum liquid is refined, a slag remover is added to the aluminum liquid for the next process. The slag remover is composed of 25-45 sodium chloride, 30-50 potassium chloride, 3-7 calcium fluoride, and 1-6 aluminum chloride. The slag remover removes impurities in the molten metal and makes the slag loose and easy to remove through chemical reactions, thereby improving the purity of the aluminum liquid and the quality of the metal. After the slag removal is completed, the temperature of the aluminum liquid is adjusted to the pouring temperature for die casting.

5. The high-precision automobile cylinder head casting molding process according to claim 1 is characterized in that: S2 uses the prepared cylinder head sand mold for die casting. The sand mold is preheated before die casting, and the prepared aluminum liquid is poured into the mold and then the mold is closed. After the mold is closed, the air is evacuated, and several air grooves are led out by using the slag bag. The customized exhaust plate and synchronous stop valve are connected, and then connected to the vacuum pipe of the vacuum system. The vacuum system moves to the injection port of the material pipe after the mold closing is confirmed according to the working order of the die casting machine, forming a closed state between the mold cavity and the material pipe. The valve on the output pipe of the gas tank of the vacuum system is opened to perform air extraction. After the injection is completed after fast injection and pressurization, the injection is stopped and the valve of the vacuum system is closed, and the air extraction is stopped to reduce the bubble rate and improve the quality of the casting. The vacuum extraction lasts for 3 seconds, the pouring temperature is 660, and the injection time is 5 seconds.

6. A high-precision automobile cylinder head casting molding process according to claim 5, characterized in that: After the vacuuming is completed, the formed casting is subjected to secondary pressurization for 8 seconds. After the secondary pressurization is completed, the mold air top blowing is started. When blowing, the mold is fixed in the working area, and the cylinder is connected to the blowing pipe on the mold to ensure that the cylinder and the blowing pipe are tight and leak-free. The air pressure of the cylinder is adjusted according to the actual situation to control the air flow in the blowing pipe. When the air pressure is adjusted, the cylinder can be started to make the air flow flow out of the blowing pipe, lift the mold, and blow out the debris sucked into the pipe during vacuuming.

7. The high-precision automobile cylinder head casting molding process according to claim 1 is characterized in that: Before S3 milling machine processing, use hydraulic press to trim the castings after die casting to recycle waste materials, and then use sanding machine to grind excess scraps. The milling sequence of cylinder head is top and bottom planes, transition positioning reference processing, main positioning reference processing, front and rear end faces and two side surfaces processing, general hole system processing of each surface, fine milling of bottom surface, guide valve seat bottom hole and fine processing. The bottom plane is fine milled once before the valve seat guide bottom hole fine processing process. If the reference locating pin is obviously worn after repeated positioning use, consider arranging two sets of locating pins or re-fine reaming the original locating pins.

8. The high-precision automobile cylinder head casting molding process according to claim 1 is characterized in that: S4 will be packed and put into storage after passing the quality inspection. Pay attention to anti-rust, moisture-proof and dust-proof measures during packaging.

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