Sheet metal refers to the steel plate whose thickness is much smaller compared to its length and width.
It has poor transverse bending capacity and is not suitable for applications subject to transverse bending loads. Thin plate is metal in terms of its material, but because of its special geometry thickness is very small, so the processing of thin plate components has its own special characteristics.
And thin plate components related to the processing technology has three categories: (1) material: it includes shearing and punching. (2) forming: it includes bending, folding, crimping and deep drawing.
(3) connection: it includes welding, bonding and so on. The structural design of thin plate components should mainly consider the requirements and characteristics of the processing technology.
In addition, pay attention to the batch size of the components. Thin plate components are widely used because of the following advantages of thin plate: (1) easy to deform, so that a simple process can be used to manufacture a variety of forms of components.
(2) thin plate components light weight. (3) small amount of processing, due to the high quality of the surface of the plate, the thickness of the direction of the small size tolerance, the plate surface does not need to be processed.
(4) easy to cut, welding, can manufacture large and complex components. (5) Shape specification, easy to automatic processing.
2 structural design guidelines.
2. Sheet metal design need to have what knowledge
1, pro / e (sheet metal) plate and cad is just a drawing tool, the real technology to understand the process of sheet metal.
2, the following incomplete, for reference only, please go to the Internet to download. Punching is divided into ordinary punching and precision punching, due to the different processing methods, the processability of punched parts is also different.
At present, the structure of our communication products is generally only used in ordinary blanking. The following introduction to the process of blanking refers to the structure of the ordinary blanking process.
2.1 The shape and size of the punched parts are as simple and symmetrical as possible to minimize the waste in the layout. Fig. 3.1.1 Sampling of punched parts 2.2 Sharp corners should be avoided in the shape and bore of punched parts.
In the straight line or curve of the connection to have a rounded connection, arc radius R ≥ 0.5t. (t for the material wall thickness) Figure 3.2.1 Minimum value of the radius of the rounded corners of the punched parts 2.3 Punching parts should avoid narrow and long cantilever and narrow grooves Punching parts of the depth of the protruding or concave part of the depth and width of the part, in general, should be not less than 1.5t (t for the material thickness), at the same time, you should avoid the narrow long incision and and Too narrow groove, in order to increase the edge strength of the corresponding parts of the mold.
See Figure 3.3.1. Figure 3.3.1 Avoid narrow and long cantilever and groove 2.4 Punching preference for round holes, punching has a minimum size requirement punching preference for round holes, punching the minimum size of the hole with the shape of the hole, the mechanical properties of the material and the thickness of the material.
Figure 3.4.1 Examples of punching shapes Material Diameter of circular hole b Width of short side of rectangular hole b High-carbon steel 1.3t 1.0t Low-carbon steel, brass 1.0t 0.7t Aluminum 0.8t 0.5t * t is the thickness of the material, and the minimum dimensions of the punched hole are generally not less than 0.3mm.* A list of commonly used material grades in the company corresponding to high-carbon steel and low-carbon steel is shown in Appendix A of Chapter 7.
Table 1 List of minimum dimensions of punched holes 2.5 Punching hole spacing and hole margin The minimum distance between the edge of punched holes of a part and the shape of the part and the holes from the shape has some limitations with the part and the shape of the holes, see Fig. 3.5.1 When the edge of the punched holes and the edge of the shape of the part are not parallel, the minimum distance shall be not less than the thickness of the material, t; when they are parallel, the minimum distance should not be less than 1.5t.
Fig. 3.5.1 Hole margins, hole spacing of punched parts Schematic diagram 2.6 Bending parts and deep-drawing parts punching, the hole wall and the straight wall should maintain a certain distance between the hole wall bending parts or deep-drawing parts punching, the hole wall and the straight wall of the workpiece should maintain a certain distance between the hole wall and the straight wall of the workpiece (Fig. 3.6.1) Fig. 3.6.1 Distance between the hole wall of the bending parts and drawing parts and the straight wall of the workpiece 2.7 Screws, bolts overhanging and countersunk seat screws, bolts overhanging and countersunk seat of the structure of dimensions in accordance with the following table selected Take. For countersunk seat for countersunk head screws, if the sheet metal is too thin to ensure that both the hole d2 and countersunk hole D, priority should be given to ensure that the hole d2.
Table 2 for screws, bolts and countersunk holes * Requirements for sheet metal thickness t ≥ h. Table 3 for countersunk head screws countersunk seat and holes * Requirements for sheet metal thickness t ≥ h.
Table 4 countersunk seat for countersunk rivets and holes 2.8 Burr burrs on blanked parts Limit values and design notation 2.8.1 Limit values of punched parts burr The punched parts burr is not allowed to exceed a certain height, the limit values of punched parts burr height (mm) are shown in the table below. Material wall thickness Material tensile strength (N/mm2) >100~250 >250~400 >400~630 >630 f m g f m g f m g f m g f m g>0.7 ~1.0 0.12 0.17 0.23 0.09 0.13 0.17 0.05 0.07 0.1 0.03 0.04 0.05> ;1.0 ~1.6 0.17 0.25 0.34 0.12 0.18 0.24 0.07 0.11 0.15 0.04 0.06 0.08>1.6 ~2.5 0.25 0.37 0.5 0.18 0.26 0.35 0.11 0.16 0.22 0.06 0.09 0.12>2.5 ~4.0 0.36 0.54 0.72 0.25 0.37 0.5 0.2 0.3 0.4 0.09 0.13 0.18* Class f (Precision) is suitable for higher requirement parts; Class m (Medium) is suitable for medium requirement parts; Class g (Rough) is suitable for general requirement parts.
Table 5 Limit values of burr height for stamped parts 2.8.2 Requirements for burr labeling in design drawings * Direction of burr: BURR SIDE. * Part to be burred: COIN or COIN CONTINUE.
Generally do not entire structural components break all the pressure burrs, this will increase the cost. Try to use it in the following situations: exposed breaks; sharp edges that are often touched by human hands; holes or slots that need to be passed over the cable; parts with relative sliding.
Figure 3.8.2.1 Example of burr labeling in sheet metal structural design drawings 3 Bending 3.1 Minimum bending radius of bent parts When a material is bent, on its fillet area, the outer layer receives stretching and the inner layer is compressed. When the material thickness 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, so the structural design of the bending parts, should avoid too small bending fillet radius.
The minimum bending radius of the company's commonly used materials are shown in the table below. No. Material Minimum bending radius 1 08, 08F, 10, 10F, DX2, SPCC, E1-T52, 0Cr18Ni9, 1Cr18Ni9, 1Cr18Ni9Ti, 1100-H24, T2 0.4t2 15, 20, Q235, Q235A, 15F 0.5t3 25, 30, Q255 0.6t4 1Cr13, H62 (M, Y, Y2, cold rolled) 0.8t5 45, 50 1.0t6 55, 60 1.5t7 65Mn, 60SiMn, 1Cr17Ni7, 1Cr17Ni7-Y, 1Cr17Ni7-DY, SUS301, 0Cr18Ni9, SUS302 2.0t? The bending radius is the inside radius of the bending part , 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 6 company commonly used metal materials minimum bending radius list 3.2 straight edge height of bending parts 3.2.1 general case of the minimum straight edge height requirements of the straight edge of the bending parts of the height should not be too small, the minimum height of the requirements according to (Fig. 4.2.1): h>2t.
Fig. 4.2.1.1 bending parts of the straight edge of the height of the minimum value of the height of the 3.2.2 Special requirements for the height of the straight edge if the design of the Need to bend the straight edge height h ≤ 2t,, then first of all to increase the height of the bending edge, bending and then processed to the required size; or in the bending deformation zone after processing shallow groove, and then bending (as shown in the figure below). Figure 4.2.2.1 Special case of straight edge height requirements 3.2.3 Bending side with beveled side straight edge height When bending side with beveled side 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 Bending side with beveled side of the straight side of the height of the 3.3 Hole margin on the bending part of the hole margin distance: first punching and then bending, the hole The position 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 7 hole edge distance on the bent parts 3.4 Local bending process cut 3.4.1 The bending line of the bending parts 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 cracks, the bending line can be moved a certain distance in order to.
3. Sheet metal basics
Sheet metal for sheet metal (usually below 6mm) a comprehensive cold working process, including shearing, punching/cutting/compounding, 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 and 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. What is Sheet Metal Construction
Sheet metal construction is the processing and fabrication of thin metal sheets: a sheet is a steel plate that is much smaller in thickness than it is in width.
It has poor transverse bending resistance and is not suitable for use in applications subject to transverse bending loads. Thin plate is metal in terms of its material, but because of its special geometry thickness is very small, so the processing of thin plate components has its own special characteristics.
And thin plate components related to the processing technology has three categories: (1) material: it includes shearing and punching. (2) forming: it includes bending, folding, crimping and deep drawing.
(3) connection: it includes welding, bonding and so on. The structural design of thin plate components should mainly consider the requirements and characteristics of the processing technology.
In addition, pay attention to the batch size of the components. Thin plate components are widely used because of the following advantages of thin plate: (1) easy to deform, so that a simple process can be used to manufacture a variety of forms of components.
(2) thin plate components light weight. (3) small amount of processing, due to the high quality of the surface of the plate, the thickness of the direction of the small size tolerance, the plate surface does not need to be processed.
(4) easy to cut, welding, can manufacture large and complex components. (5) Shape specification, easy to automatic processing.
5. Sheet metal design should pay attention to what
General design for the 8 ~ 10mm, the gap is too small to cause a fall when the fan blade touch the sheet metal, and then damaged, the fan blade gap is too large the wind volume will become smaller.
2. Axial fan blade tip should be in the middle of the width of the guide ring, too close to the front and back of the easy to cause the air volume, noise deviation from the best design value. 3. The width of the guide ring in the 40 ~ 50mm, too short to expand the role of the pressure is small, too wide and difficult to process.
4. axial fan center in the center of the height of the slightly higher position, because the lower part of the air volume is slightly larger, the center of the axial fan height of the slightly higher position can make the condenser the entire surface of the air intake wind speed uniformity. 5. in the spacer and the condenser should be as large as possible at the tip of the angle, in order to avoid the place because of the poor flow of air caused by the low speed of the local wind, resulting in the phenomenon of the place easy to frost.
6. Compressor piping should be as small as possible to avoid wasting space. 7. Try to use a good leaf type (height, diameter, etc.) of the axial fan. 8.
In order to improve the cooling air volume and reduce the motor speed and reduce vibration and noise. 8. Overall layout: the distance of the axial fan from the condenser should be as far as possible and keep uniform, in order to get the wind speed uniformity and reduce the noise, such as axial fan and condenser bending the distance to pay attention to. 9.
9. condenser from the height of the chassis to ensure that more than 5mm, in order to prevent frost after the end of the water stagnation caused by the water into ice. 10. electrical mounting plate should be as far as possible not to affect the piping space.
11. Sheet metal *** sound caused by compressor vibration can be solved by applying anti-vibration adhesive on the sheet metal. 12. In order to check the feasibility of the outdoor unit structure, it is necessary to carry out destructive experiments, drop experiments, in order to find out what may be wrong with the design, and to improve it as soon as possible.
Second, the indoor machine design guidelines (split) 1. cross-flow fan and evaporator surface distance is best in more than 10mm, you can avoid due to the flow of incoming air caused by the cross-flow fan noise, such as (sudden, sudden ...) 2. try to use more than one fold (more than 2 folds) evaporator and try to make the surface of the evaporator ring package cross-flow fan, so that the air intake area to expand the air speed becomes lower, the intake noise is also reduced. 3. The air inlet noise is also reduced. 3. air outlet frame outlet area should be as small as possible (under the premise of ensuring the air volume) so that the air speed is easy to ensure that improves the applicability of use, so that the cold air and hot air can be sent to every corner of the room as far as possible.
4. The gap between the wind guide plate and the two ends of the face frame to ensure that about 3mm, in order to avoid thermal expansion of the wind guide plate and jammed. 5. Cross-flow fan diameter as large as possible, in order to ensure that the wind volume at the same time, the motor speed is low vibration naturally smaller, and at the same time, we must ensure that the cross-flow fan and the chassis of the worm shell gap in 3mm or more, in order to improve the assembly rate of compliance.
6. into the grille ventilation area to ensure and as large as possible, in order to get into the wind resistance reduction. 7. try to use advanced cross-flow fan, such as oblique buckle is not equidistant, the tower oblique buckle is not equidistant fan in order to get into the continuous compression of the wind, in order to avoid equidistant fan discontinuous air intake caused by the noise of the fan blades.
8. After long-term operation for 15 days and spray water test to ensure that the ability to eliminate condensation, to avoid water dripping to the ground. 9. In order to test the life of the fan into the panel need to open the panel 50 to 100 times (with normal force) without damage.
10. Check the structural reliability of the indoor unit, must be destructive experiments fall test, in order to try to find problems early and solve them. III. Indoor machine design (cabinet) 1. Send style grille the lowest and uppermost blade should be designed: blade downward tilt, the lowermost blade to maintain the level, blade upward tilt, the uppermost blade to maintain the level, in order to facilitate the solution to the problem of condensation.
2. Not at the same time the amount of air supply (different models at the same time) should try to ensure that the distance between the air supply is appropriate, can be resolved by narrowing or enlarging the ventilation area of the air supply outlet. 3. Through the evaporator flow path more into the air duct design, etc. so that the temperature of the air at the air supply as far as possible to maintain uniformity, to avoid the phenomenon of the outlet on the cold and the next hot.
4. Because the motor is directly fixed to the backplane, so we must consider the backplane vibration caused by the *** vibration sound, and try to use the motor and the backplane of the rotary connection. 5. indoor machine noise mainly exists in the air inlet, so we should try to minimize the inlet grille of the air inlet resistance. 6. the installation of the evaporator should try to tilt to improve the effect of heat transfer and the uniformity of the temperature of the air. 7. the evaporator should be installed as much as possible.
7. Because of the indoor machine sheet metal parts of the end of a larger inch, assembly after the machine shape and position tolerance is difficult to guarantee, so the zero with the size should be accurate. 8. must be transported, drop test to verify the reliability of the structural design.
V. Window unit Window machine 1. the angle of the outer box shutter should be greater than 45 °, and the ventilation area is small enough to facilitate the improvement of outdoor air volume. 2. because the indoor and outdoor fan **** with a motor, in the same speed of indoor and outdoor air volume should be proportional to the column, in order to facilitate the performance of the design. 3.
3. The outdoor side of the water ring (axial fan ) from the chassis distance of about 3 ~ 8mm, in order to facilitate the water, enhance the condenser heat transfer effect. 4. Because the condenser air supply area is small, and the air volume compared to the splitter is also smaller, so the overall heat transfer capacity has dropped dramatically, the heating is easy to frost, in general, is not designed for cooling and heating machine VI. Dehumidifier 1. low-temperature environment should be used to fully consider the reliability of the defrost, so that the compressor running dehumidification time and ventilation defrost time proportionally balanced, the experimental verification should be easy to frost conditions, such as 10 ° C for a long period of time running 8 ~ 12 hours to verify that the evaporator is not frozen reliability, and then consider the efficiency of the dehumidification on this basis.
2. Domestic dehumidifiers should be low noise design, the noise value should not be higher than 45db (A). VII. Mobile air conditioning 1. Mobile air conditioning is equivalent to the "cold fan" so the distance of the air distance is quite important, in the case of noise allows to increase the air velocity as much as possible.
2. Because the condenser wind area and volume restrictions, and the user to use the exhaust pipe will be discharged outside the hot air, the condenser circulating air volume will be greatly affected, in order to solve this problem should try to strengthen the outdoor centrifugal fan and the design of the snail shell. 3. with the dehumidifier evaporator anti-freezing design should be given due consideration to the running time of the air supply and defrosting, to avoid freezing of the evaporator. 4.
6. Basics of Sheet Metal
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, molding, welding.
This specification describes the process requirements to be observed for each type of processing. 1.2 Keywords: sheet metal, underfeeding, bending, stretching, molding, rows of samples, minimum bending radius, burrs, rebound, dead center, welding 2 Underfeeding Underfeeding can be divided into universal punching, number of punching, shearing machine opening, laser cutting, wind cutting according to the different processing methods, underfeeding the processing of craftsmanship is also different.
Sheet metal undercutting methods are mainly digital punching and laser cutting 2.1 Digital punching is processed by CNC punching machine, plate thickness processing range of Cold rolled sheet, hot rolled sheet less than or equal to 3.0mm, aluminum less than or equal to 4.0mm, stainless steel less than or equal to 2.0mm 2.2 Punching has a minimum size requirements Punching the minimum size of the hole with the shape of the hole, the mechanical properties of the material and the thickness of the material is related. Figure 2.2.1 Example of punched hole shapes Material Diameter of circular hole b Width of short side of rectangular hole b High-carbon steel 1.3t 1.0t Low-carbon steel, brass 1.0t 0.7t Aluminum 0.8t 0.5t * t is the thickness of the material, and the minimum size of the punched hole is generally not less than 1mm.
* A list of commonly used material grades in the company corresponding to high-carbon steel and low carbon steel can be found in Appendix A of Chapter 7. Table 1 List of the minimum sizes of punched holes. 2.3 Hole spacing and hole margin for digital punching The minimum distance between the edge of punched holes of parts and the shape of holes from the shape has certain limitations depending on the shape of the parts and holes, see Fig. 2.3.1.
When the edge of punched holes is not parallel to the edge of the shape of the parts, the minimum distance should be not less than the thickness of the material, t; and when it is parallel, it should be not less than 1.5t. Fig. 2.3.1 Schematic diagram of hole margins and hole spacing of punched parts 2.4 For bending parts When punching and deep-drawing parts, a certain distance should be maintained between the wall of the hole and the straight wall When punching bending or deep-drawing parts, a certain distance should be maintained between the wall of the hole and the straight wall of the workpiece (Fig. 2.4.1) Fig. 2.4.1 Distance between the wall of the hole of the bending parts and drawing parts and the straight wall of the workpiece 2.5 Overhangs and countersunk seats of screws and bolts The structural dimensions of the overhangs and countersunk seats of screws and bolts shall be selected in accordance with the following table.
For countersunk seat for countersunk head screws, if the sheet metal is too thin to ensure that both the overbore d2 and countersunk hole D, priority should be given to ensure that the overbore d2. Table 2 Overbore for screws and bolts * Requirements for the sheet metal thickness t ≥ h.
Table 3 Countersunk seat for countersunk head screws and overbore * Requirements for the sheet metal thickness t ≥ h. Table 4 Countersunk seat for countersunk rivets and overbore 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.
The 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, high processing costs! 3 bending 3.1 minimum bending radius of the bending parts When the material is bent, its rounded area, the outer layer receives stretching, the inner layer is compressed. When the material thickness 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 fractures will occur, therefore, the structural design of bending parts, should avoid too small bending fillet radius.
7. Basics of Sheet Metal
Introduction to Sheet Metal Working Processes
1 Introduction
1.1 Introduction
According to the basic processing methods of sheet metal parts, such as underfeeding, bending, stretching, molding and welding. This specification describes the process requirements to be observed for each type of processing.
1.2 Keywords
Sheet metal, undercutting, bending, stretching, forming, row of samples, the minimum bending radius, burrs, rebound, dead center, welding
2 Undercutting
Undercutting according to the different processing methods can be divided into general punching, number of punches, shearing machine openings, laser cutting, air cutting, due to the different processing methods, undercutting the processing of the process of craftsmanship is also different. Different. Sheet metal under the way mainly for the number of punching and laser cutting
2.1 Digital punching is the use of CNC punching machine processing, sheet metal thickness processing range of cold rolled sheet, hot rolled sheet less than or equal to 3.0mm, aluminum less than or equal to 4.0mm, stainless steel less than or equal to 2.0mm
2.2 Punching has a minimum size
Punching the minimum size of the hole with the shape of the hole, mechanical properties and thickness of the material. mechanical properties and material thickness.
Figure 2.2.1 Examples of punched hole shapes
Material Diameter of circular hole b Width of short side of rectangular hole b
High-carbon steel 1.3t 1.0t
Low-carbon steel, brass 1.0t 0.7t
Aluminum 0.8t 0.5t
* t is the thickness of the material, and the minimum size of the punched hole is generally not less than 1mm. p> * For a list of commonly used company material grades corresponding to high carbon steel and low carbon steel, see Chapter 7, Appendix A.
Table 1 List of minimum dimensions of punched holes
2.3 Hole spacing and hole margin for digital punching
The minimum distance of the edge of the punched holes of a part from the profile is subject to a certain limitation depending on the shapes of the part and the holes, as shown in Fig.2.3.1. When the edge of the punched holes and the edge of the profile of the part are not parallel, this minimum distance should be not less than 1mm. When the punched edge is not parallel to the edge of the part shape, the minimum distance should be not less than the thickness of the material t; when it is parallel, it should be not less than 1.5t.
Fig. 2.3.1 Schematic diagram of the hole edge distance and hole spacing of the punched parts
2.4 When punching of bending parts and deep-drawing parts, a certain distance should be maintained between the wall of the holes and the straight wall of the part
When punching of bending or deep-drawing parts, the wall of the holes and the straight wall of the workpiece should be kept at a certain distance (Fig. 2.4.1). Figure 2.4.1)
Figure 2.4.1 Distance between the hole wall of the bending and drawing parts and the straight wall of the workpiece
2.5 Screws, bolts and countersunk holes and countersunk seat
Screws, bolts and countersunk holes and countersunk seat of the structure of the size of the selection of the following table to take. For countersunk head screw countersunk seat, if the sheet metal is too thin to ensure that the hole d2 and countersunk holes D at the same time, should be given priority to ensure that the hole d2.
Table 2 for screws, bolts and countersunk holes
* Requirement for sheet metal thickness t ≥ h.
Table 3 for countersunk head screw countersunk head seat and holes
* Requirement for sheet metal thickness t ≥ h.
Table 4 for countersunk rivets and countersunk head seat
Table 4 for countersunk rivets, countersunk head seat, countersunk head seat and holes
Table 4 for countersunk rivets Countersunk head seat and overbore for countersunk head rivets
2.6 Laser cutting is a laser machine flight cutting process, sheet metal thickness processing range for cold rolled plate hot rolled 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, high processing costs!
3 bending
3.1 Minimum bending radius of the bent parts
When the material is bent, its rounded area, the outer layer receives stretching, the inner layer is compressed. When the material thickness 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 fractures will occur, therefore, the structural design of bending parts, should avoid too small bending fillet radius.