Originally Posted By: liuguoqing88
Sheet metal directory 1, the purpose of the study and its advantages 2, sheet metal emotion 3, sheet metal molding of the common methods 4, sheet metal unfolding of the principles and methods of calculation 5, the rapid calculation methods and unfolding coefficient of the empirical value of the 6, sheet metal of the common methods of molding the unfolding of the calculation of the several methods 7, PEM Introduction to standard parts Cheng Guoming I. Sheet metal Learning Objectives: to increase the understanding of all present on the sheet metal forming process; know how to calculate the unfolding dimensions; sheet metal advantages: 1, high material utilization; 2, high labor productivity; 3, light weight; 4, able to obtain the shape of complex parts that are difficult to process or can not be processed by other processing methods. According to statistics, sheet metal parts account for more than 90% of all metal products. II. Brief Idea 1, sheet metal: refers to the thickness of a uniform sheet metal, through some processing methods, will be processed to meet the application requirements of the parts. 2, sheet metal molding: is the flat area of the sheet metal will be bent to a certain angle, arc shape, stretching, twisting and other molding process. 3, sheet metal unfolding: is the molding of the sheet metal parts unfolded into a flat sheet of the process. III. Common Methods of Sheet Metal Forming: The common methods of sheet metal forming are divided into two main categories: 1. Separation mainly includes shearing, punching (dropping, punching), and notching. It is characterized by the plate being subjected to external forces, the stress exceeds the strength limit, which makes the plate sheared and separated.2. Deformation mainly includes bending (bending and rolling), stretching, twisting, forming (undulating, flanging) and so on. Characterized by the plate by the external force, the stress exceeds the yield limit, but below the strength limit, after plastic deformation into a certain shape. After unloading the force does not exceed the yield limit after unloading the force after unloading the force exceeds the yield limit, below the limit of strength IV. sheet metal unfolding of the principle of calculation and calculation method we are based on what to calculate the unfolding of it?1, the principle of calculation a. Analysis of the bending process, the material outside the surface of the bending at the tensile tension, the inner surface of the extrusion (see the right
2. sheet metal basics
Originally Posted By: Encyclopedia of New Thought
The basic knowledge of bending a bending machine: bending machine is a sheet metal processing into a variety of angles of the equipment; coupled with the CNC function, effectively improve the processing accuracy and productivity. Second, the commonly used bending tool classification: 1. upper mold 2. lower mold three, bending tool division: the normal length of the tool is 835mm; to facilitate the bending of different lengths, often the whole length of the tool is divided into the following segments: 10 + 15 + 20 + 40 + 50 + 100 + 100 + 200 + 300 = 835 four, the corresponding relationship between the plate thickness and width of the groove: routinely, the groove width of the plate thickness of 6 times. 6 times. Wanjia source now stipulates the thickness of the plate and slot width control table is as follows: V. According to the above table of control when processing the minimum bending size (the note bending size including plate thickness): VI, the conventional bending order: 1. short side after the long side: In general, all four sides are bent, the first short side after the long side of the folding of the workpiece is conducive to the processing and bending mold assembling 2. periphery after the middle: under normal circumstances, generally from the periphery of the workpiece to the center of the folding 3. Start to the center of the workpiece folding 3. First local after the whole: If the workpiece inside or outside there are some different from other bending structure, generally the first of these structures after bending and then folding the other parts 4. Considering interference with the situation, the reasonable arrangement of the bending order: bending order is not set in stone, according to the shape of the bending or the workpiece obstacles to the appropriate adjustment of the processing order VII, bending operation precautions: 1. When the bending operation, always pay attention to personal safety, need to pay attention to the following points: A. When the equipment is open, do not reach from the bending machine's knife into the adjustment of the rear gear; should go directly to the back of the equipment to adjust the B. Processing parts, the human body should be in the parts outside the scope of activities, to avoid scraping the parts to the human body C. Processing of large workpieces, the human body is best to stand in the side of the workpiece, in order to operate the D. Workpiece should be held at any time to avoid falling or smashing the human body E. Workpiece or smashing the human body E. Workpiece should be held at any time to avoid falling or smashing the human body. Workpiece or smash the human body E. Operation of the human body to stand firm, not because of the workpiece
3. Sheet metal basics
Sheet metal for sheet metal (usually in the 6mm below) a comprehensive cold process, including shearing, punching/cutting/composite, splicing, molding (such as car body) and so on. Its distinctive feature is the consistent thickness of the same part.
Sheet metal parts are characterized by light weight, high strength, conductive (able to be used for electromagnetic shielding), low cost, good mass production performance, etc., and are widely used in the fields of electronics and electrical appliances, communications, automotive industry, medical devices, etc. For example, sheet metal parts are an essential part of the computer chassis, cell phones, MP3.
Sheet metal parts are indispensable for life everywhere. Sheet metal parts are made by filament power winding, laser cutting, heavy duty machining, metal bonding, metal drawing, plasma cutting, precision welding, roll forming, sheet metal bending and forming, die forging, and water jet cutting.
Extended Information
With the increasing application of sheet metal, the design of sheet metal parts has become a very important part of the product development process, mechanical engineers must be proficient in the design of sheet metal parts to make the design of the sheet metal to meet the functionality of the product and the appearance of the product and other requirements, but also to make the stamping die manufacturing is simple and low cost.
The base material of SECC is a general cold rolled steel coil, which is degreased, pickled, plated, and post-treated in a continuous zinc galvanizing line to become an electro-galvanized product.
SECC not only has the mechanical properties and similar processability of general cold rolled steel sheets, but also has superior corrosion resistance and decorative appearance. SECC has great competitiveness and substitutability in the market of electronic products, home appliances and furniture. For example, computer chassis commonly used is SECC.
Modern sheet metal processes include: is filament power winding, laser cutting, heavy-duty machining, metal bonding, metal drawing, plasma cutting, precision welding, roll forming, sheet metal bending molding, water jet cutting.
3D software, SolidWorks, UG, Pro/E, SolidEdge, TopSolid, etc. have a sheet metal parts, mainly through the editing of 3D graphics and get the data required for sheet metal parts processing (such as unfolding diagrams, bending lines, etc.) as well as for the numerical control punching machine (CNC Punching Machine) and so on to provide data.
Baidu Encyclopedia - Sheet Metal
4. Sheet metal to learn what knowledge
1. Clamping: countersinking, tapping, reaming, drilling. Countersinking angle is generally 120 ℃ for pulling rivets, 90 ℃ for countersunk head screws, tapping inch bottom hole.
2. flanging: also known as pumping holes, flanging holes, that is, in a smaller base hole drawn into a slightly larger hole, and then tapping, mainly with a thin plate thickness of sheet metal processing, to increase its strength and the number of threaded turns to avoid slippery teeth, generally used for thinner plate thickness, and its holes perimeter of the normal shallow flanging, the thickness of basically unchanged, allowing for a thickness of the thinned out 30-40%, you can get a height of 40-60% higher than normal flanging Large height of 40-60%, with extruded thin 50%, you can get the maximum height of the flap, when the plate thickness is large, such as 2.0, 2.5 and so on above the thickness of the plate, can be tapped directly.
3. Punching: is the use of mold forming process, general punching processing of punching, cutting corners, drop, punching convex package (bumps), punching tearing, drawing holes, forming and other processing methods, its processing needs to have the appropriate mold to complete the operation, such as punching drop mold, convex package mold, tearing mold, drawing holes in the mold, forming molds, etc., the operation of the main attention to the location, directionality.
4. Pressure Rivet: Pressure Rivet in the case of our company, there are mainly pressure riveting nuts, screws, loose, etc., which is through the hydraulic pressure riveting machine or punch to complete the operation, will be riveted to the sheet metal parts, and riveting mode, need to pay attention to the directionality.
5. Bending: Bending is a 2D flat piece, folded into D parts. Its processing needs to have a folding bed and the corresponding bending molds to complete, it also has a certain bending order, the principle is that the next knife does not interfere with the first fold, will produce interference after the fold.
5. Automotive sheet metal is mainly learning what content
First, is a technical means of automotive repair, this aspect of automotive sheet metal is equal to the automotive sheet metal repair, refers to the car after a collision to repair the body, that is, in addition to the body of corrosion and decorative painting work all the rest of the work. Such as the analysis of auto body damage, auto body measurement, auto body sheet metal shaping, tensile straightening, stress relief welding, and auto body accessories assembly, adjustment and other work.
Second, sheet metal is a type of auto body repair, mainly for the appearance of the body, the external body (such as bumpers, doors) of the replacement, repair, orthopedic, baking paint also belongs to the sheet metal work area, within the sheet metal and a specific division of labor, sheet metal in the broader sense of the above content is covered in its entirety, and the narrower sense of the sheet metal is only the replacement of the external body, as well as the use of welding, orthopedic and other general repair of the body of work, under the broader sense of the sheet metal There are also playing putty, sanding, and painting, and polishing, in the internal division of labor, everyone said the sheet metal, generally refers to the broad sense of the.
6. Detailed sheet metal basics overview
Say the problem to be more specific, the following article do not know if I can help you.
Introduction to Sheet Metal Processing 1 Introduction 1.1 Introduction According to the basic processing of sheet metal parts, such as the following material, bending, stretching, forming, welding. This specification describes the process requirements to be noted for each type of processing.
1.2 Keywords sheet metal, undercutting, bending, stretching, forming, row sample, minimum bending radius, burrs, rebound, dead center, welding 2 undercutting undercutting according to the different processing methods can be divided into universal punching, number of punching, shearing machine openings, laser cutting, wind cutting, due to the different processing methods, undercutting the processing of the process of craftsmanship is also different. Sheet metal undercutting methods are mainly digital punching and laser cutting 2.1 Digital punching is processed with CNC punching machines, plate thickness processing range of Cold rolled sheet, hot rolled sheet less than or equal to 3.0mm, aluminum plate less than or equal to 4.0mm, stainless steel less than or equal to 2.0mm2.2 Punching has a minimum size of the requirements of the minimum size of punching and the shape of the hole, the mechanical properties of the material and the thickness of the material is related.
Figure 2.2.1 Examples of punched hole shapesMaterialsCircular hole diameterbRectangular hole short side widthbHigh-carbon steel1.3t1.0tMild steel, brass1.0t0.7tAluminum0.8t0.5t* t is the thickness of the material, and the minimum size of the punched hole is generally not less than 1mm.* For a list of the commonly used company grades of high-carbon steel, mild steel, see Appendix A in Chapter 7.
Table 1 Punched holes List of minimum dimensions 2.3 Hole spacing and hole margin for digital punching The minimum distance between the edge of the punched hole of the part and the shape of the hole from the profile has certain limitations depending on the shape of the part and the hole, see Fig. 2.3.1. When the edge of the punched hole and the edge of the profile of the part are not parallel, the minimum distance should be not less than the thickness of the material, t; when they are parallel, the minimum distance should be not less than 1.5t.
Fig. 2.3.1 Schematic diagram of hole margin and hole spacing of punched parts 2.4 Bending and deep-drawing parts punching, the hole wall and the straight wall should maintain a certain distance between the bending or deep-drawing parts punching, the hole wall and the straight wall of the workpiece should maintain a certain distance between the hole wall (Fig. 2.4.1) Fig. 2.4.1 Bending and drawing parts hole wall and the distance between the straight wall of the workpiece 2.5 Screws, bolts overhangs and countersunk seat screws, bolts overhangs and countersunk seats of the structural dimensions of the selected according to the following table take. For countersunk seat for countersunk head screws, if the plate is too thin to ensure that both over-hole d2 and countersunk holes D, priority should be given to ensure that the over-hole d2.
Table 2 for screws, bolts, over-hole * Requirements for sheet metal thickness t ≥ h. Table 3 for countersunk head screw countersunk seat and over-hole * Requirements for sheet metal thickness t ≥ h.
Table 4 for countersunk rivets, countersunk seat and over-hole 2.6 Laser cutting is done with a Laser cutting is a laser machine flight cutting process, plate thickness processing range for cold plate hot plate less than or equal to 20.0mm, stainless steel less than 10.0mm. Its advantages are processing plate thickness, cutting workpiece shape fast, flexible processing. The disadvantage is that it can not be processed into shape, mesh parts should not be processed in this way, processing costs are high! 3 bending 3.1 bending parts of the minimum bending radius of the material bending, its rounded corners of the region, the outer layer received stretching, the inner layer is compressed.
When the thickness of the material is certain, the smaller the inner r, the more serious the stretching and compression of the material; when the tensile stress of the outer fillet exceeds the ultimate strength of the material, cracks and breaks will occur, therefore, the structural design of bending parts, should be avoided too small bending radius of the fillet. The minimum bending radius of the company's commonly used materials is shown in the table below.
No. Material minimum bending radius 108, 08F, 10, 10F, DX2, SPCC, E1-T52, 0Cr18Ni9, 1Cr18Ni9, 1Cr18Ni9Ti, 1100-H24, T20.4t215, 20, Q235, Q235A, 15F0.5t325, 30, Q2550.6t41Cr13, H62 (M, Y, Y2, cold rolled) 0.8t545, 501.0t655, 601.5t765Mn, 60SiMn, 1Cr17Ni7, 1Cr17Ni7-Y, 1Cr17Ni7-DY, SUS301, 0Cr18Ni9, SUS3022.0t?The bending radius is refers to the inner radius of the bent part, and t is the wall thickness of the material. ?t is the wall thickness of the material, M is the annealed state, Y is the hard state, Y2 is 1/2 hard state.
Table 5 List of minimum bending radius of commonly used metal materials in the company 3.2 Straight edge height of the bending piece 3.2.1 Minimum straight edge height of the general requirements of the straight edge height of the bending piece should not be too small, the minimum height according to the (Fig. 4.2.1) requirements: h>2t. Fig. 4.2.1.1 The minimum height of the straight edge of the bending piece 3.2.2 The height of the straight edge of the special requirements of the special requirements of the bending piece if design If the design requires the straight edge height of the bent part h ≤ 2t,, then first of all to increase the height of the bending edge, after bending and then processed to the required size; or in the bending deformation zone after processing a shallow groove, and then bending (as shown in the following figure).
Figure 4.2.2.1 Requirements for the height of the straight edge in special cases 3.2.3 Height of the straight edge of the bending side with a beveled edge When the bending side with a beveled edge of the bent parts (Figure 4.2.3), the minimum height of the side of the h=(2~4)t>3mm Figure 4.2.3.1 Height of the straight edge of the bending side with a beveled edge 3.3 Hole margins on the bending parts Hole margins: first Punching and then bending, the location of the hole should be outside the bending deformation zone to avoid deformation of the hole when bending. The distance from the hole wall to the bending edge is shown in the table below.
Table 6 hole margins on the bent parts 3.4 Local bending of the process of cutting 3.4.1 bending parts of the bending line should avoid the location of the size of the sudden change in the local bending of a section of the edge, in order to prevent the sharp corners of the stress concentration generated by the bending of the fracture, can be moved a certain distance from the bending line in order to leave the size of the sudden change in the place (Figure 4.4.1.1 a), or to open the process of groove (Figure 4.4.1.1 b), or punched process holes (Fig. 4.4.1.1 c) . Note the dimensional requirements in the figure: S ≥ R; slot width k ≥ t; slot depth L ≥ t + R + k / 2.
Figure 4.4.1.1 Design treatment of local bending 3.4.2 When the hole is located in the bending deformation zone, the form of notch taken When the hole is located in the bending deformation zone, the form of notch used when the hole in the bending deformation zone, the form of notch Example (Fig. 4.4.2.1) Fig. 4.4.2.1 notch example of the form of 3.5 belt Figure 4.4.2.1 Example of notch form 3.5 Bending edges with beveled edges should avoid the deformation zone Figure 4.5.1 Bending edges with beveled edges should avoid the deformation zone 3.6 Design Requirements for Dead-Edge Punching The length of the dead edge of the punched edge is related to the thickness of the material. As shown in the figure below, the general minimum length of the dead edge L ≥ 3.5t + R.
Where t is the wall thickness of the material, R is to beat the dead edge of the previous process (as shown in the figure below, right) the minimum internal bending radius. Figure 4.6.1 Dead edge of the minimum length of L3.7 design to add the process of positioning holes in order to ensure accurate positioning of the blank in the mold, to prevent bending blank offset and scrap, should be added in advance in the design of the process of positioning holes, as shown in the figure below.
Especially for multiple bending and forming parts, must be process holes for positioning reference, in order to reduce the cumulative error, to ensure product quality. Figure 4.7.1 Process positioning holes added during multiple bending 3.8 Labeling dimensions related to bending parts, taking into account the process Figure 4.8.1 Example of bending parts labeling As shown in the figure above, a) punching followed by bending. b) punching followed by bending. c) punching followed by bending. d) bending followed by bending. e) bending followed by bending.
7. What knowledge is needed to learn sheet metal painting
1. Need to understand the mild steel sheet metal bending, molding, proofreading, welding knowledge, do not have to be too in-depth, know a little on the line.
2. Need to master the knowledge of pre-painting treatment, such as rust, degreasing, filling the pit putty, grinding and other knowledge.
3. Need to master the knowledge of the type of paint, what surface with what paint, primer or topcoat or masking paint.
4. Need to master the knowledge of paint construction, that is, what method of painting, is spray paint, or brush paint, or electrostatic spray paint, how to operate.
5. Need to master the paint matching and color mixing knowledge.
The above knowledge to go to the new bookstore to buy some books in this area to read and understand or ask to teach the people on the line. The latter is not easy to find someone to teach.
8. I just apprenticed automotive sheet metal Learn this essential knowledge and skills and common sense and what tools to let
Sheet metal is a comprehensive cold working process for sheet metal, including shearing, punching/cutting/compounding, folding, welding, riveting, splicing, molding (such as car body) and so on.
Its distinctive feature is the consistent thickness of the same part. Sheet metal factory in general the basic equipment including shearing machine, CNC punching machine / laser, plasma, water jet cutting machine / composite machine, bending machine, and a variety of auxiliary equipment such as: uncoiler, calibrator, deburring machine, spot welder and so on.
This material describes in detail the various steps and precautions of sheet metal, giving guidance and demonstration to sheet metal workers. Sheet metal factory in general, the basic equipment including shearing machine (Shear Machine), CNC punching machine (CNC Punching Machine) / laser, plasma, water jet cutting machine (Laser, Pla *** a, Waterjet Cutting Machine) / composite machine (bination Machine), Bending Machine) and various auxiliary equipment such as: uncoiler, leveling machine, deburring machine, spot welding machine.
Usually, the three most important steps in a sheet metal factory are shearing, punching/cutting, and bending. Sheet metal is sometimes also known as wrenching, the word comes from the English platemetal, generally some sheet metal by hand or mold stamping to produce plastic deformation, forming the desired shape and size, and can be further welded or a small amount of machining to form more complex parts, such as chimneys commonly used in the home, tin stove, and car shells are sheet metal parts. Sheet metal processing is called sheet metal processing.
Specifically, such as the use of sheet metal to make chimneys, iron barrels, oil tanks, oil pots, ventilation pipes, elbow size, Tianyuan place, funnel-shaped, etc., the main process is to shear, bending, buckling, bending and molding, welding, riveting, etc., requires a certain geometric knowledge. Sheet metal parts is sheet metal parts, that is, through stamping, bending, stretching and other means to process the parts, a general definition is - in the process of processing the thickness of the parts remain unchanged. Corresponding to the casting, forging, machining parts, such as the car outside the iron shell is sheet metal parts, stainless steel to do some of the cabinet is also sheet metal parts.