According to the difference in the structure of sheet metal parts, the process can be different, but generally do not exceed the following points.
1. Feeding: There are various feeding methods, mainly in the following ways
Sheet metal processing in Sichuan
①. Shearing machine: It is the use of shearing machine to cut the bar simple material, it is mainly for the mold blanking forming preparation processing, low cost, accuracy less than 0.2, but can only process no holes no cutting corners of the bar or block material.
②. Punching machine: is the use of punching machine one step or more steps in the plate parts after the development of the sheet blanking to form various shapes of materials, its advantages are short time consuming, high efficiency, high precision, low cost, suitable for mass production, but to design the mold.
③. NC cutting, NC cutting first to write CNC machining program, the use of programming software, will draw the expansion diagram into the NC digital drawing machine tool can identify the program, so that it according to these programs step by step on the plate to cut the shape of the plate, but its structure is subject to the tool structure, low cost, accuracy of 0.15.
④. Laser feeding, is the use of laser cutting method, the structure of the plate will be cut out on the large plate, the same as NC feeding need to write laser program, it can be under a variety of complex shapes of flat parts, high cost, accuracy of 0.1.
⑤. Sawing machine: The main use of aluminum profiles, square pipe, diagram pipe, round bar material, such as low cost, low precision.
one Pliers: sinking hole, tapping, reaming, drilling sinking hole Angle is generally 120℃, for pulling rivets, 90℃ for countersunk head screws, tapping the British bottom hole.
2. Cuff: Also called pumping hole, turning hole, *** is to draw a slightly larger hole on a smaller base hole, and then tap, mainly with sheet metal processing with relatively thin plate thickness, increase its strength and the number of threads, to avoid slipping teeth, generally used for plate thickness is relatively thin, the normal shallow flanging around the hole, the thickness basically does not change, allowing a thickness of 30-40% thinner, Can be obtained than the normal flanging height of 40-60% higher height, with 50% thin, can get the best flanging height, when the board thickness is larger, such as 2.0, 2.5 and more board thickness, you can directly tap.
3. Punching machine: is the use of mold forming processing process, the general punching machine processing has punching, cutting Angle, blanking, punching convex bag (convex point), punching tear, pumping holes, forming and other processing methods, the processing needs to have the corresponding mold to complete the operation, such as punching blanking die, convex mold, tearing die, pumping die, forming die, etc., the operation mainly pays attention to position, direction.
4. Press riveting: Press riveting *** For the company, there are mainly pressure riveting nuts, screws, loose, etc., which is completed by hydraulic press riveting machine or punch, the riveting to the sheet metal parts, there are rising riveting methods, need to pay attention to the direction.
5. Bend; Bending *** is to fold 2D flat parts into D parts. Its processing requires a folding machine and the corresponding bending mold to complete, it also has a certain bending order, the principle is that the first folding does not interfere with the next cut, will produce interference after folding.
If the number of bending strips is T=3.0mm or less, calculate the slot width by six times the plate thickness, such as: T=1.0, V=6.0, F=1.8, T=1.2, V=8, F=2.2, T=1.5, V=10, F=2.7, T=2.0, V=12, F=4.0
l Folding machine mold classification, straight knife, curved knife (80℃, 30℃)
l When the aluminum plate is bent, there is a crack, the lower die slot width can be increased to increase the upper die R(annealing can avoid cracks)
l Precautions when bending: Ⅰ drawing surface, required plate thickness, quantity; ⅱBending direction Ⅲ bending Angle; Ⅳ bending size; The appearance of Ⅵ, electroplated chromium materials and parts shall not have creases.
The relationship between bending and pressure riveting process, under normal circumstances, the first pressure riveting and then bending, but there are materials and parts after the pressure riveting will interfere with the *** first folding and then pressing, and some need to bend - pressure riveting - then bending and other processes.
6. Welding: Welding definition: The atoms and molecules of the welded material form a whole from the crystal lattice distance
① Classification: a fusion welding: argon arc welding, CO2 welding, gas welding, manual welding
b Pressure welding: spot welding, butt welding, bump welding
c Brazing: electrochrome welding, copper wire
② Welding method: aCO2 gas shielded welding
b Argon arc welding
c spot welding, etc
d Robot welding
The selection of welding method is based on the actual requirements and material, generally speaking, CO2 gas shielded welding is used for iron plate welding. Argon arc welding for stainless steel, aluminum plate welding, robot welding, can save hours, improve work efficiency and welding quality, the highest work intensity.
③ Welding symbol :Δ fillet welding, type I welding, V-type welding, unilateral V-type welding (V) with blunt edge V-type welding (V), spot welding (O), plug welding or slot welding (R), rolled edge welding (χ), unilateral V-type welding with blunt edge (V), U-type welding with blunt edge, J-type welding with blunt edge, bottom welding, and welding
④ Arrow lines and joints
(5) Welding loss and preventive measures
Spot welding: The strength is not enough to hit the convex point, imposing the welding area
CO2 welding: high productivity, less energy consumption, low cost, strong rust resistance
Argon arc welding: shallow solution, slow melting speed, low efficiency, high production cost, with tungsten defects, but with good welding quality advantages, can weld non-ferrous metals, such as aluminum, copper, magnesium and so on.
⑥ Welding deformation cause: insufficient preparation before welding, need to increase the fixture
Welding fixture poor improvement technology
Bad welding sequence
7 Welding deformation effect correction method: flame effect correction method
Vibration method
