Guanggong precision drive plunger parts processing technology regulations

The purpose of the experiment is to analyze and solve practical engineering problems by the comprehensive application of "Mechanical Manufacturing Technology Foundation" and related course content. Through the drawing up of plunger machining process regulations, the students' ability to formulate parts machining process regulations and analyze process problems, as well as the ability to design machine tool fixtures. During the design process, students should be familiar with the relevant standards and design materials, and learn to use the relevant manuals and databases. The development of plunger machining process regulations is a basic training for future mechanical manufacturing technology work. Task objective: After finishing the machining precision design of "precision drive plunger", design and complete the batch or mass production processing process design according to the instructor's opinions on the accuracy requirements of the parts. The specific parts drawing is provided by the instructor. First, plunger machining process specification formulation task book cylindrical sleeve plunger task content: 1) The above formulation of the designated parts (or parts group) of the machining process regulations, the preparation of machining process cards, the selection of machine tools, fixtures, tools, measuring tools, auxiliary tools; 2) Necessary analysis, demonstration and calculation of the developed process; 3) Determine the blank manufacturing method and the total margin of the main surface; 4) Determine the processing allowance, process size, tolerance and technical requirements of the main process; 5) Carry out the process design of the main process, prepare a reasonable machining process specification card, draw a process diagram, and select the cutting amount; 6) Selection of positioning reference, design of fixture for a certain process, draw fixture assembly drawing and main parts drawing; 7) Write the design specification. Second, calculate the production program, determine the type of production three, the main function and technical requirements of the parts 1, the function of the parts of the plunger and cylinder sleeve is a small power transmission of the general cooperation, such as small motor, pump a type of transmission and sliding coordination. 2, part process analysis  This part is a rotary part, the main processing surface is Φ10H8 hole and Φ10f7 cylinder, and both have a high coaxial requirement of 0.015, is the processing technology needs to focus on the problem. Secondly, due to the assembly requirements of the plunger and cylinder sleeve, the cylindrical surface of Φ10f7 has the end runout requirements. And the matching surface of the two workpieces has a roughness of 1.6 requirements. 1, determine the blank manufacturing method The main function of this part is to transfer small power, and its work needs to bear little impact load, but it requires a high strength and stiffness, and maintain the accuracy of the match. Due to the need for sliding friction, the surface must have sufficient hardness. Therefore, the plunger must be made of 45 steel, tempered first, and then quenched on the surface. The inner surface of the cylindrical sleeve should also undergo surface hardening. 2. Determine the total allowance of the plunger: determine the total allowance of 6mm on the diameter and 8mm on the height (axial) direction. The feed rate is f=0.4mm/r and the cutting speed is v=100m/min. Cylindrical sleeve: Determine the total margin of 6mm on the inside and outside diameter, and the total margin of 8mm on the height (axial) direction. The feed rate is f=0.6mm/r, and the cutting speed is v=100m/min. 1, select the surface processing method cylindrical sleeve: Φ10H8 hole reference table S-2, and consider: ① Because the workpiece belongs to the course design content, belongs to a single piece of small batch production; ② Heat treatment of parts will cause large deformation, in order to ensure the accuracy of the Φ10H8 hole and the coaxiality with the surface, the hole needs to be processed after heat treatment. Therefore, it is determined that the processing method of drilling - reaming - grinding is used before heat, and the grinding method is used after heat. The cylindrical material of Φ10f7 must undergo the processing method of coarse turning - semi-fine turning - fine turning to achieve the accuracy of the cylindrical surface. Two ends: the general requirements are not high, just a rough car can be. 1) Cylindrical sleeve: precision selection of cylindrical sleeve design processing outer surface and drilling are positioned to the axis, so the outer circle is the design basis. Considering the stability and reliability of positioning, a large end face is selected as the second positioning precision reference. In the grinding process, in order to ensure the coaxiality of the outer surface of the cylinder and the hole, the outer surface is selected as the positioning reference. 2) Plunger: The design of the precision standard plunger is mainly to process the outer surface of the cylinder, so it is also chosen to locate the axis, so the outer circle is the design basis. 1, cylindrical sleeve: 1) thick car outer circle, thick car end (ordinary lathe, three jaw chuck); 2) semi-fine car outer round, thick car end (ordinary lathe, three-jaw chuck); 3) the outer circle of the fine car, the end face of the fine car (ordinary lathe, three-jaw chuck); 4) Drilling (ordinary lathe, drill, three-jaw chuck); 5) Cut off and rough the other end of the car (ordinary lathe, drill, three-jaw chuck); 6) Reaming (vertical drilling machine, three-jaw chuck); 7) Intermediate inspection; 8) Grinding holes (internal grinder, pitch chuck); 9) Inspection; 10) Heat treatment; 11) Final inspection. 2, plunger: 1) thick car outer round, thick car end (ordinary lathe, three-jaw chuck); 2) Non-finishing shaft segment in the middle of the rough car, that is, non-matching surface (ordinary lathe, three-jaw chuck); 3) The finishing surface of the outer circular ends of the semi-finishing car, that is, the mating surface, the end face of the semi-finishing car, (ordinary lathe, three-jaw chuck); 4) Intermediate inspection; 5) Fine turning mating surface, fine turning end face (ordinary lathe, three-jaw chuck); 6) Inspection; 7) Heat treatment; 8) Final inspection. Through this machining process course design, I understand that the process refers to the process of changing the shape, size, relative position and nature of the production object (such as raw materials, blanks, semi-finished products, parts, etc.) in the production process, so that it becomes a finished product or a semi-finished product. In this design and the practical operation of the machine tool, I learned a lot, the process refers to the process of changing the shape, size, relative position and nature of the production object (such as raw materials, blanks, semi-finished products, parts, etc.) in the production process, so that it becomes a finished product or semi-finished product. In the process design engineering, it is necessary to comprehensively consider the requirements of product accuracy, existing processing conditions, economic benefits and manpower. Parts that do not require high precision can be without finishing; It is not possible to process parts with high precision on machines with poor machining quality. In the process of redesign, the quality of products and the efficiency of production should be taken into account. In the process of product design, we can not only consider how to design the product how beautiful and how innovative, we also need to consider the problems and difficulties that the product may encounter in the processing process, can it be processed on the existing equipment, how efficient the processing is, how the quality of the processing is, and whether the processing cost is high or low. These are the factors that require us to take into account when designing products. To achieve the "unity of quality and economic benefits", we as the future mechanical design manufacturers in the future design to fully take into account all aspects of the problem, can not patronize quality and forget economic benefits, but can not sacrifice product quality for economic benefits! 1) Zhao Jiaqi edited, Mechanical Manufacturing Technology Course Design Guide (2nd edition) -- General higher education mechanical and electrical planning textbook; China Machine Press 2004-2-12) Zhang Longxun, Mechanical Manufacturing Technology Course Design Guide and Exercises, China Machine Press, 20073) Li Yimin, Ed., Concise Manual of Mechanical Manufacturing Process Design; China Machine Press; 19994) Ai Xingxiao Shigang, Ed., Cutting Parameters Manual, China Machine Press; 19945) Fan Wang, Ed. Practical machinery manufacturing process design manual; China Machine Press, 2008