Internship location: Luoyang First Tractor Factory
Contents
Chapter 1: Introduction
Part 1: Internship Objectives
Part 2: Introduction to the Internship Unit
Chapter 2: Internship Process
Part 1: Factory Instruction
Part 2: Internship Process
1. Visited the forging branch in the morning on 2009.07.20
2. Visited the gear factory in the afternoon on 2009.07.20
3. Visited the Engineering Machinery Co., Ltd. on 2009.07.21 < /p>
Seven. 2009.07.24 Visit to the No. 1 Assembly Plant
Eight. 2009.07.25 Visit to the Precision Casting Factory
Chapter 3 Internship Experience
Chapter 4 References
Chapter 1: Introduction
Production internship is an important part of university internship. The school attaches great importance to it and approves a large amount of funds every year to arrange students in various majors. Visit various factories for internships, increase students' knowledge, consolidate textbook knowledge, let us understand some basic operation processes of factories, and lay a solid foundation for our future study and work.
Of course, our major is no exception. 10~~12 weeks before the start of school, the school arranged for students from our major to participate in production internships. So more than 200 of us, led by teachers with excitement, arrived at Luoyang Yituo visited and practiced respectively, and we learned a lot of knowledge.
Through our own visits, we also searched for various books and materials and searched for relevant materials on the Internet, so that our knowledge can be consolidated and improved, and we can successfully complete this internship report, so the purpose of this report is The content mainly includes four chapters.
Part One: Internship Objectives
The important goal of this internship is to enable students to acquire perceptual knowledge of basic production through internships, connect theory with practice, and expand their knowledge; at the same time, professional internships also It is an important channel for tempering and cultivating students' business abilities and qualities, cultivating contemporary college students with the spirit of hard work and hard work. It is also an important way for students to contact the society, understand the status of the industry, and understand the national conditions. It gradually realizes the transformation from students to society and cultivates our initial Ability to undertake technical work, preliminary understanding of basic methods and techniques of business management; experience of the content and methods of business work. This practical knowledge is a very necessary foundation for us to study subsequent courses and even future work. We will achieve the following points in this internship: 1. Through factory production internship, go deep into the production front line to conduct inspections and investigations, acquire necessary perceptual knowledge and enable students to comprehensively understand the production organization and production process of the machinery manufacturing factory. , understand and control the basic production practical knowledge of this major, consolidate and deepen the theoretical knowledge learned, and lay the foundation for subsequent professional course teaching, course design, and graduation design. 2: During the internship, through the analysis of the machining process of sample parts, as well as the machine tools, fixtures and measuring tools used in the part processing process, the ability to combine theoretical knowledge and practice to analyze and solve problems. 3: Through internships, have extensive contact with workers and listen to special reports by workers and technicians, learn from their good industrial experience, technological reforms and scientific research results, and learn from their contribution to the construction of the four modernizations. 4: Expand your knowledge by visiting relevant factories, controlling the entire production process of a machine from blank to product, organizational management, equipment selection and workshop arrangement. 5: By keeping internship diaries and writing internship reports, we can exercise and cultivate our ability to observe, analyze problems, and collect and organize technical materials.
2. Internship content (1) Understand the factory’s production process, production line layout, and technical equipment; (2) Record part design and production processes and equipment; (3) Control knowledge and methods of machining processes (4) Understand cutting tools Knowledge, familiar with the structure, selection, use of commonly used cutting tools, etc. (5) Understand the knowledge of machine tools and CNC systems, especially CNC equipment such as machining centers (6) Understand the enterprise production management model, and learn advanced management methods (7 ) Familiar with and consolidated the knowledge of casting process and equipment, consolidated the theoretical knowledge we learned, and allowed us to learn knowledge that cannot be learned in textbooks, and increased our knowledge. During the internship, we understood some basic operating processes of the factory. , have a preliminary understanding of the structure of machine tools, their processing methods and control methods, and a more detailed understanding of the processing technology of some parts, which will lay a good foundation for future jobs. Of course, it is more important for us to consolidate the theoretical knowledge we usually learn and understand how much equipment we have really learned, so as to make up for our own shortcomings.
Part 2: Introduction to the internship unit
China YTO Group Co., Ltd. is headquartered in Luoyang, a famous historical and cultural city in China and the ancient capital of the Nine Dynasties. YTO Group is a Hong Kong-based company in Mainland China. The only listed agricultural machinery manufacturing and sales enterprise. Its predecessor, the First Tractor Manufacturing Factory, is a comprehensive company with factories, subsidiaries and representative offices in many regions at home and abroad, focusing on machinery manufacturing.
In 1955, as one of the 156 key construction projects aided by the former Soviet Union during the "First Five-Year Plan" period of New China, under the instructions of Chairman Mao Zedong, China's largest tractor manufacturer, YTO, was established in Jianxi, Luoyang in the former Sui Dynasty. The ground was broken for Emperor Yang's royal garden. After three years of construction and improvement, YTO's first tractor rolled off the production line on July 20, 1958. On November 1, 1959, Yituo was officially completed. In 1990, it was rated as a "National First-Class Enterprise" by the Enterprise Management Committee of the State Council. In 1997, China First Tractor Group reorganized its tractor-related businesses, assets, and debtors and carried out joint-stock reform, and established First Tractor Co., Ltd. in accordance with the law. . Afterwards, the joint-stock company issued H shares overseas and was listed in Hong Kong on June 23 of the same year. In 1999, the "Dongfanghong" trademark was recognized as a well-known trademark in China by the State Administration of Administration. In 2003, the three series of "Dongfanghong" brand series (tracked, wheeled) tractors and industrial bulldozers, and "Luoyang" brand road rollers won the "Henan Province" "Famous Brand Product" title. In January 2000, the company overall passed the ISO9002:1994 quality management system certification, and in May 2003, the company overall passed the ISO9001:2000 quality management system certification. At present, in order to further meet the needs of production and market development, the company has fully implemented the situation/occupational health and safety management system standards in the company since 2004, ensuring that it passed third-party certification in the first half of 2005, and established a quality management system based on ISO9001 Based on the system, ISO9001 is organically combined with ISO14001 and OHSMS management systems to form an orderly and efficient management platform to comprehensively improve the company's management level. After years of development and changes in the market situation, Yituo has also embarked on the development path of product diversification. Currently, its products mainly include the following four categories:
1. Agricultural machinery: with high horsepower Wheeled tractors, high-horsepower crawler tractors, small and medium-horsepower wheeled tractor combine harvesters.
2. Power machinery: diesel engines, presses
3. Engineering machinery: road rollers, industrial bulldozers, forklifts, excavators, cranes
4. Automobile categories: various trucks, transport vehicles, sprinkler trucks and other products.
Now, YTO starts from the mechanism and system and actively establishes a modern enterprise system. By adopting methods such as joint ventures, joint-stock reform, leasing and contracting, and liberalization of operations, we will actively explore capital management and strive to move towards a modern enterprise group that operates across industries, regions, ownerships, and transnational operations, and gradually establish an adaptability
< p>Chapter 2: Internship ProcessPart One: Factory Entry Education
The so-called factory entrance education is mainly safety education. In the afternoon of the first day we arrived in Luoyang, They organized us to conduct safety education, and the YTO staff explained to us the entry into the factory and safety education.
Students have always ignored the safety instructions that teachers have emphasized every time they go out since elementary school, unless the teacher actively intervenes. However, this time the YTO staff allowed us to thoroughly and truly experience the scenes behind the accident. The bloody tragedy fully taught us the importance of safety in the factory. Its safety protection can be divided into six categories:
1. Mechanical protection, mainly mechanical protection.
2. There are two types of chemical poisons: gaseous and liquid.
3. Burning and explosion hazards are mainly caused by the combined effects of mechanical, chemical and thermal effects.
4. Heat persecution.
5. Electrical persecution.
6. Other persecutions.
The only way to prevent these safety hazards is to strictly comply with the factory's safety requirements. Important notes:
1. Smoking is strictly prohibited in any area of ??the factory;
2. You must queue up to enter the factory area and branch factories;
3. It is prohibited to gather in the square;
4. Protect gardens and protect flowers and plants;
5. Do not block the entrance and exit of the factory, and do not stand on the main road of the factory;
6. Keep the factory area hygienic;
7. Photography is strictly prohibited in the factory area;
8. Drinking alcohol is strictly prohibited during the production internship;
9. Dress according to the unified requirements. It is prohibited to wear slippers, sandals, and high heels into the factory. Long pants are required, and the cuffs and collars of clothes are tightly buttoned. People with long hair should put their hair into a hat and are not allowed to carry a backpack into the factory;
10. The factory is a production organization, and the various machine tools in it are strictly observed and not touched;
11 .Due to machine tool oil lubrication and splashing, the road surface is slippery, so be careful not to slip when entering the factory;
12. After entering the factory, it is forbidden to listen to MP3 while walking around;
13. Pay attention to yourself and School image;
14. Spitting is prohibited;
Part 2: Internship Process
1. Visit to the Forging Branch
1. Overview:
Professional The forging base was completed and put into operation in 1959, with an annual production capacity of 35,000 tons of forgings and more than 800 varieties. It is fully equipped with three large forging (crankshaft) production lines and one small crankshaft production line. It has built a domestically advanced suspended heat treatment and tempering line. Before the introduction, it had established cooperative relationships with more than 30 domestic manufacturers, and can provide users with We supply various types of high-quality forgings for agricultural machinery, engineering machinery, power machinery, military industry and foreign trade, with weights ranging from 0.1Kg to 270Kg. In recent years, we have introduced advanced Japanese technology and developed a variety of crankshaft series forgings. In particular, the technological level and quality of hammer forged large and complex crankshafts are among the best in the country. Some products are processed and exported to the United States and Southeast Asia. In terms of product quality, we always take user satisfaction as our purpose, ensuring "high-quality products, excellent services, meeting requirements, and continuous improvement" to provide a reliable guarantee for enlightening the market and occupying the market.
2. Production equipment and its functions:
1) Workshop 1:
The important equipment is the heat treatment furnace, including continuous normalizing furnace and continuous quenching and tempering furnace; forging cold calibration equipment: mainly hydraulic presses and straightening hammers, whose important role is to eliminate product deformation caused by the release of forging stress during the heat treatment process; forging cleaning equipment, mainly shot peening machines or shot blasting machines, which play a role in forgings To the cleaning and strengthening effect, the surface of the cleaned forging is smooth and the surface
hardness is relatively high.
2) Workshop 2:
There are 2 workshops in Workshop 2. In the light forging workshop, the important equipment includes 7 flat forging machines and 4 forging presses; in the die forging workshop, Important equipment includes 1 free forging hammer, 4 air forging hammers, and 10 steam mode forging hammers. There are also three related auxiliary equipment: heating furnace, whose main function is to heat the blank; press, whose main function is to complete trimming or trimming and punching; thermal correction equipment, whose main function is to eliminate deformation (mainly trimming Or deformation caused by trimming or trimming and punching).
3. Production process
The general process of forging is as follows:
Blanking - 26 production lines - forging (heating, trimming, punching , correction) - cooling - heat treatment (may cause deformation of parts) - cleaning (may also cause deformation of parts) - cold correction.
2. Visit the gear factory
1. Overview:
A professional gear and assembly machining center with 659 important process equipment, including American Lisson production line, CNC lathe, Italian CNC gear hobbing machine, CNC gear shaping machine, heat treatment production line. The American Gleason bevel gear production line has an annual production capacity of 100,000 pieces. At present, it has gradually become a supplier of gearbox products, automotive products, agricultural machinery products, engineering machinery products and business products.
2. Important equipment:
Radial drilling machine, mainly used for deep hole processing of parts, benchtop drilling machine, vertical lifting table milling machine, semi-automatic spline shaft milling machine, gear hobbing machine, Horizontal square table surface grinders, multi-tool lathes, straight bevel gear planers, electrical control cabinets and other machine tools. Arc gear wheel precision cutting machine, machine tool automatic chip conveyor, slotting machine.
3. Important products:
1), spur cylindrical gears, helical cylindrical gears, spur bevel gears, spiral bevel gears, involute splines and rectangular splines key.
The processing area is: Dmaxx 1250 m15, accuracy level 6, and can grind gears of Dmax×800 m16. It can be used in agricultural machinery, engineering machinery, diesel engine and other industries.
2), road roller series gearbox assembly, harvester gearbox assembly, milling machine gearbox assembly, hydraulic excavator gearbox assembly, loader gearbox assembly and 140, 145 , 153 differential subtraction assembly and bridge.
In the afternoon we visited Yituo Gear Factory. The master in the factory told us about the situation of the factory, and then we entered the workshop. We must also pay attention to safety here. All kinds of lathes and machine tools rotate at high speed, which is very dangerous, so we must be very vigilant. When I got here, I really came to a kingdom of gears. There are all kinds of gears. You can see various gears that you can only hear about but not see in books, which makes my understanding of gears more comprehensive and comprehensive. Concrete.
3. Visit to Construction Machinery Co., Ltd.
1. Overview
The company is a joint venture between China First Tractor Co., Ltd. and Brilliance China Machinery Holdings Co., Ltd. Large enterprises. The company covers an area of ??140,000 square meters and a construction area of ??98,000 square meters. The company was founded in the 1970s. It was formerly a heavy-duty military industry enterprise of the Ministry of Machinery Industry. It has a large production scale and strong technical force. Since the establishment of the joint venture in 1993, it has relied on its military technology and scientific research capabilities to continuously develop high-performance and cost-effective engineering machinery products that meet national conditions and market demand.
2. Important products:
The following products have been introduced to the market successively: wheel loaders, industrial bulldozers, and vibratory rollers in three series and dozens of models, among which Dongfanghong T100 Industrial The bulldozer was rated as a provincial quality product. As a well-known "Dongfanghong" engineering machinery product at home and abroad, it is sold in thirty provinces, municipalities and autonomous regions in China, and exported to countries and regions such as Europe, Asia, Africa, Latin America and Australia. The company always adheres to the policy of "quality first, customer first", has passed the 1S09001 quality system certification, and has been awarded the "May 1st Labor Certificate", "Top Ten Units for Professional Ethics Construction" and "Excellent Foreign Investment Enterprise" by the province and city many times. and other honorary titles. Participating in military industry production and switching to engineering machinery production, the company has always maintained the corporate spirit of "inheriting military industry ethics and striving to be first-class in the industry". With a good foundation and strong strength, it has developed market-oriented: wheel loaders, crawler bulldozers and Three series of vibratory rollers.
3. Important equipment:
The company not only has more than 50 large-scale, precise and rare advanced equipment produced by famous domestic and foreign enterprises, but also more than 400 important processing equipment, such as CNC gas cutting. Machines, roller presses, spot welders, turners, double shears, boring machines, gantry planers, vertical lathes, single-arm planers and other large machine tools. In addition, it has internationally advanced testing instruments in terms of measurement and testing, which provides reliable guarantee for product quality.
4. Workshop introduction:
The company has five workshops:
Workshop 1, the structure workshop, is mainly responsible for cutting materials;
Workshop 2, riveting workshop, mainly used for welding of various parts;
Workshop 3, machining workshop, mainly used for processing parts;
Workshop 4, Painting workshop, mainly used for spraying products;
Workshop 5. Assembly workshop, mainly used for assembly;
5. Parts painting process:
< p>Rust removal (mainly shot blasting method) - first spraying (spraying primer) - drying - second spraying (spraying topcoat) - drying - final painting - experiment ( Divided into road test and load test) - washing - drying - final packaging - product deliveryIV. Visit the stamping factory
1. Overview:
Flager Body Co., Ltd. is a limited liability company restructured in February 2006 based on the former stamping plant of China YTO Group Co., Ltd. It was founded in 1956. Flegg Company inherited the important business of the original stamping factory and is committed to the manufacturing and sales of covers, structural parts, cabs, fuel tanks and other products for automobiles, agricultural machinery and engineering machinery, as well as the stamping, welding and painting of general machinery products. and machining. The general production process of wall parts is like this. Game parts still need some mechanical processing to meet our design and application requirements. These parts also need to add some machining steps. Within each process, we also need to design a more reasonable processing step according to the processing requirements. Thin-walled parts like these are generally film forged to improve production efficiency and accuracy; therefore, design a good process during the cold forging process. The mold is very important. In subsequent processing, these thin-walled parts need to be fixed and positioned. In order to achieve higher processing efficiency, we need to design a good fixture. I will analyze the fixture in detail later.
2. Introduction to each workshop equipment and production products:
Material preparation workshop: There are more than 20 shearing machines and a rust removal and pickling production line. The important thing is to prepare blanks for the next production process. Preparation; punching workshop: There are double-action 630-ton mechanical stamping machines, single-action double-point 800-ton and 630-ton mechanical presses, and mainly produce various types of cab covers, box-shaped deep-drawn parts and medium-thick plate stamping parts; The second workshop: single-acting four-point 1,000-ton mechanical press, single-acting single-point 2,000-ton mechanical press, double-acting 1,300-ton stretching press, and double-acting 1,000-ton press. Its products are mainly extra-large thin plate parts, such as : Large stamping parts such as door panels, floors, ceilings, instrument panels; welding workshop; 150~200KW spot welding machines, rotary spot welding machines, fuel tank sealing spot welding machines and other arc welding machines, mainly used for welding and assembling various machine models Components used; paint shop; cathode electrophoresis machine, microcontroller-controlled automatic electric circuit control machine, assembly process of parts and alloy parts, double-process degreasing surface phosphating treatment and other functions.
3. Process flow:
The process flow of the stamping factory is: material preparation area - stamping - welding - painting - final assembly - finished product
5. Visit Yituo Heat Treatment Plant
1. Overview:
The heat treatment plant is a professional factory established on December 26, 2002 based on the integration of Yituo Company’s heat treatment resources. . It has fixed assets of more than 73 million yuan; a production area of ??14,916 square meters; and more than 370 sets of various equipment. It has many years of process history in supporting the production of tractors, automobiles, construction machinery and power machinery. It is used in carburizing, nitriding, carbonitriding, induction quenching, quenching and tempering, normalizing, annealing, etc. of various finished parts. The internationally advanced crankshaft quality centering machine is installed in the heat treatment process production as well as surface oxidation, phosphating, electroplating and other treatment processes. The project has rich and mature technical management experience, and the overall annual production and processing capacity is more than 20,000 tons.
2. Equipment and functions
Double-row furnace is mainly used for carburizing and quenching. The supporting materials methanol is a carburizing agent and acetone is a protective gas; shot peening machine It is mainly used to increase the surface compressive stress of parts and improve the surface quality of products; the straightening machine is mainly used to correct the deformation of parts due to heat treatment and shot peening.
3. Heat treatment process:
(1) Gas-heated gas carburizing furnace
Quenching medium: gasoline
Preheating temperature ：900℃
Carburizing temperature: 920℃
Strong penetration temperature: 920℃
Diffusion temperature: 900℃
（二 ) Electrically heated gas carburizing furnace
Propane + shielding gas
Quenching medium: gasoline
After quenching, 200 ℃ low temperature tempering
Use pressure and cooling method after quenching to prevent deformation
Shielding atmosphere: methanol and acetone
Low-pressure correction machine: reduce deformation
Shot blasting machine: improve the surface of the workpiece Appearance, advance surface hardness.
Raw material gas: CO, methane, nitrogen
Preparation process: propane and air→mix and pressurize→react above 1000°C→quickly cool→send after passing the composition inspection As a protective atmosphere in the carburizing furnace.
4. Internship summary:
Improve the surface hardness of the workpiece through carburization → obtain hard and brittle martensite
(1) Fully consider the heat treatment deformation factors , leaving a processing allowance.
(2) Avoid designing sharp corners to avoid deformation during heat treatment.
(3) Try to be as symmetrical as possible when designing parts.
(4) The opening should be away from the edge of the part.
(5) Process verification must be carried out before production. First, produce in small batches to test the process and make reasonable corrections to avoid unnecessary losses caused by mass production.
VI. Visit to the Second Foundry
1. Overview:
The First Iron Foundry, which is engaged in the production of iron castings, conducted comparisons during the "Ninth Five-Year Plan" period. Large-scale technology reform. The molding department introduced the static pressure molding line of the German KW company, which is currently the largest green mold sand production line for iron castings in China and has the international advanced level in the 1990s; the sand processing department introduced the sand mixer, cooler, and moisture of the German KN company. Automatic control and other important equipment; the Melting Engineering Department introduced the American coreless variable frequency induction furnace to realize dual melting with the cupola; the Core Making Department introduced the German cold core box core making machine and installed a domestic furan resin self-hardening sand core production line. It owns an electron metallographic microscope from the UK, a direct reading spectrometer from the US, and a three-coordinate scribing instrument from Germany. The design and production of tooling molds all use CAD/CAE technology. Passed IS09002 quality system certification in 1999. At present, it can produce all kinds of gray cast iron and ductile iron castings for automobiles and tractors with a single piece weight of 50-500Kg, and has an annual production capacity of 35,000 tons. In addition to matching the products of China YTO, the four- and six-cylinder diesel engine blocks, automobiles and other diesel engine parts are also matched with several well-known domestic automobile manufacturers and diesel engine manufacturers.
2. Process flow:
Sand casting process flow: Features: Generally not limited by the size, shape, and complexity of parts, the modeling materials have a wide range of origins, the cost is low, and the application widely. According to the molding materials, they are divided into dry sand mold, green sand mold, water glass sand mold, resin sand mold and self-hardening sand mold. Process analysis (1. Process parameters 2. Sand core design) ------- Sand core making, sand making mold ---------- Melting ---------- Pouring ----------Out of the box------Cleaning------Repair welding-------Heat treatment----------Cleaning--- ----Finished Products
7. Visit to the First Assembly Plant
1. Overview
The First Assembly Plant of China First Tractor Co., Ltd. is China Agricultural Machinery Co., Ltd. The largest agricultural crawler tractor manufacturing base in the industry. The factory was founded in 1956, covering an area of ??55,800 square meters and a construction area of ??36,600 square meters. It is the backbone professional factory of the First Tractor Manufacturing Factory, one of the 156 key projects during China's first five-year plan. Since China's first 54-horsepower crawler tractor was assembled on July 20, 1958, it has an annual production capacity of 25,000 crawler tractors. After more than 40 years of development, Dongfanghong brand tractors and construction machinery have been distributed in all provinces and autonomous regions in China and exported to more than 50 countries and regions in Europe, North America, South America, Africa, East Asia, and the Middle East, and are very popular among users.
In the past ten years, 15 major technological reform projects have been completed, involving cold, hot, coating, assembly, welding and other process links, and a new general assembly line has been built, which has further improved the level of process equipment and production capacity, and strengthened the competitiveness of the company's products. The factory has nearly a thousand units of various modern equipment, including machining center flexible processing lines, gas shielded welding, imported heavy-duty vertical broaching machines, multi-axis automatic vertical lathes, microcomputer-controlled multi-function controllable atmosphere multi-purpose furnaces, bright quenching, CNC induction heating treatment and a complete set of heat treatment equipment for gear parts, shaft gear parts, etc., as well as dedicated production lines and electrostatic coating lines for shells, forks, and shaft parts. The newly built general assembly line has high technological content and complete functions. It adopts many new technologies such as industrial automatic computer monitoring, online detection, computer monitoring running-in test bench, large-screen logistics management, etc. It can realize multiple types of mixed flow equipment and high-horsepower tractors. assembly. In addition to being a professional manufacturer of the main engine of crawler tractors and bulldozer variants of First Tractor Co., Ltd., the First Assembly Plant also has the ability to improve, develop and sell various new tractor variants; it has more than 100 intermediate and senior technicians. Able to adapt to the development and changes of international and domestic markets and the different needs of users. Process design, product development and enterprise management have made extensive use of CAD, CAPP and computer network information systems (ERP); in recent years, we have independently developed crawler tractor series, hydraulic excavator series, transportation and agricultural wheel tractor series and special It is used in dozens of variant products such as crawler machinery products and is very popular among users. "Unity, dedication, and creating first-class" is the spirit of our company. At the advent of the era of knowledge economy in the 21st century, our factory is willing to cooperate with various domestic and foreign enterprises and scientific research institutions on the basis of the principles of equality, reciprocity, and mutual benefit to conduct extensive research and development on technology, products, and Trade cooperation, revitalizing agricultural equipment, and seeking future development will make the "Dongfanghong" brand famous in China and spread around the world.
8. Visit the Precision Casting Factory
1. Overview
The factory mainly uses investment casting method for production. The investment casting process flow is as follows: Making the motherboard Mold - making impressions - making wax patterns - making shells - dewaxing - baking and shaping - pouring - shelling. The dimensions of investment casting are accurate, the surface of the casting is smooth and clean, and there is no parting surface, so there is no need for further processing or less processing. Investment casting has many processes and a long production cycle. Limited by the strength of the mold shell, the weight of the casting generally does not exceed 25kg. It is suitable for the production of small and medium-sized, thin-walled and complex castings of various metals and alloys. In this factory, we can mainly combine some of the things we learned about investment casting in the classroom with the production here and think about it. From this, we should be able to see the practical matters in mold design.
2. Production process
The basic production process of investment mold making is as follows:
1) Mold making, using 2-3 molds alternately to produce wax model.
2) Repair the mold, assemble, trim the wax mold, and install the wax mold on the wax stick to form a wax mold set.
3) Make a mold shell, using water glass, quartz sand and ammonium chloride water, etc., and repeat processing to form a mold shell of about 8mm.
4) To dissolve the wax, soak it in 95 degree hot water to dissolve the wax.
5) Burn the mold shell using a gas stove to 860-950 degrees for 2-3 hours.
6) Cool, cool to 600 degrees.
7) Pouring.
8) Cleaning, use a vibration machine to shell, cast the rods separately, use a roller machine, sodium hydroxide as solvent and shot blasting machine to clean the castings.
9) Heat treatment, normalizing, quenching and tempering and other processes.
10) Clean the oxide film and use a shot blasting machine to clean it.
11) Inspection and deburring (grinding machine).
12) For magnetic particle inspection, use a magnetic stamping machine to apply magnets, put it into the magnetic suspension, use a yellow light machine to check whether there are cracks on the surface, and finally use a demagnetizer to demagnetize.
3. Process flow:
The process flow of investment casting is as follows: making master mold - making pressing - making wax pattern - making shell - dewaxing - - Roasting and modeling - Pouring - Shelling
Chapter 3: Internship experience
Through this production internship, I have a lot of feelings and a deep understanding. Before I went there, I always thought Based on the knowledge I learned from books and classes, I should have a deeper understanding of the production situation of the company. However, after I went there, I realized how naive my ideas were and realized what the book said about "paper." The true meaning of "what you learn at the beginning is shallow, and you know that you need to practice it" also clarifies the teacher's good intentions in asking us to do internships in the factory. There are many things that seem to be understood, but in reality it is a different situation. Sometimes the equipment that you think you have control over may only be superficial or an aspect of the whole, or even sometimes a wrong understanding. Without field assessment practice, you cannot create these problems. The insights and insights from this production internship are now summarized as follows:
1. It expanded my knowledge and provided a good supplement to the theoretical knowledge in the book;
2. Really Down-to-earth entry into the key production areas of the factory will help you understand the production process, the factory, and the equipment;
3. Lay a strong foundation for the study of professional knowledge and lay the foundation for future professional courses;
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4. Have an in-depth and comprehensive understanding of the professional orientation of this major, which will provide a certain guidance for future work;
5. Have a perceptual to rational understanding of production equipment, and have a practical In fact, a deep impression;
6. Have a more comprehensive understanding of the relationship between various workshops of a factory or enterprise, resource allocation, production lines, and the role of corporate culture in enterprise development;
7. The harsh working environment encourages me to study harder and prepare for better competition for jobs in the future;
8. The concept of people-oriented scientific development concept is deeply rooted in the enterprise, and human nature The concept of personalized management has also been deeply rooted in employees;
9. Self-worth can also be realized in ordinary jobs, and there are many such examples in Yitu;
10. In the future, joint efforts Our school's "Three Doings" concept further improves one's overall quality and structures and improves life.
As college students in the new era, especially in this special period, the arrival of the global financial crisis has brought unprecedented challenges and hardships to college students’ employment. As we are about to graduate, facing the big situation, we There aren't many measures, other than helplessness. However, I think there are also opportunities in the face of crises, but we often only see crises but ignore opportunities. I think that in the face of difficulties, we college students should do their jobs well, practice basic skills, be honest, do things in a down-to-earth manner, and be diligent in learning. First, we should learn the theoretical knowledge in the textbooks well, learn it, and understand it. After that, we can use our spare time to Time is combined with practice to understand theory and knowledge, and theory and practice are combined. Of course, the school also created many prerequisites for us, such as understanding internship and this production internship. Every internship brings us huge benefits and lays a good foundation for the study of our textbook theory. Of course, the most important thing is to rely on ourselves.
Chapter 4: References
1. Editor-in-chief Wang Zhong. Zheng Mingxin. Mechanical Engineering Materials Tsinghua University Press
2. Editor-in-chief Hu Gengxiang Rongyong. Materials Scientific Basics Shanghai Jiao Tong University Press
3. Editor-in-Chief Qu Huachang. Plastic Molding Technology and Mold Design Advanced Teaching Press
4. Editor-in-Chief Liu Quankun. Basic Principles of Material Molding Hefei University of Technology Press
5. Editor-in-chief Zhao Xuesong. Basics of Mechanical Manufacturing Techniques Huazhong University of Science and Technology Press
6. Editor-in-chief Zhao Changsheng. Mold Materials and Heat Treatment Manual Machinery Industry Press
< p>7. Geng Haoran. Zhang Xisheng. Chen Junhua. Cast Steel Chemical Industry Press