What is the sheet metal parts/metal fabrication?
Sheet metal parts is various forming processes for various types of metal sheets, such as mold punching and shearing, laser cutting, flame cutting, plasma cutting,waterjet cutting, bending, riveting, stretching, flanging, spinning, welding and other forming processes. Generally, we call sheet metal thickness below 3mm, which have high dimensional accuracy and surface condition requirements as precision sheet metal,usually used for some chassis cabinet,3mm to 20mm are commonly called to as medium thick plates,20mm and above are called thick plates,
What sheet metal parts do we provide?
We mainly provide sheet metal parts of around 0-20mm thickness, mainly are precision sheet metal parts and medium thickness sheet metal parts,
Blanking:
Before the laser cutting machine, many thin plates needed to be cut using shearing machine, and the size control was generally poor. The parallelism of the cutting end edges could not be guaranteed, and even due to equipment limitations, there must be a certain degree of unevenness. As an ancient punching and shearing equipment, now we usually use shearing machine for board Cutting or produce some parts that in very large tolerance, For products with high precision requirements, punching and shearing by die cutting is required, which need spend much development time and mold costs. For products with a small quantity, the cost will be relatively high. The punching and shearing die cutting usually requires high precision, and the mold material is usually Cr12, which requires heat treatment. Therefore, it is used to produce by medium wire cutting, if for large automotive parts molds, slow wire cutting may be necessary However, if quantities of products is large, the advantage of mold cutting is still large, so many factories are still using mold cutting. For example in automobile factories ,car body sheet metal parts, it will be easy to getting all the features and the size will be consistant.cost will be low too. Generally, it is okay to use a punching to cut around 8mm, but if it is thicker, it will be deform easily and the fracture edge is too large,the choice of press pressure is
Q235 carbon steel material thickness x perimeter X0.3447=press size
Stainless steel material thickness x perimeter x 0.5171=press size
CNC turret punching
Another shearing process is CNC turret punching, which is similar to CNC machine with many punching molds installed.can punching the shape of the mold installed ,and various shapes can be combined. The splicing of linear molds can also be used for straight line cutting or irregular line cutting of sheet metal. This is commonly used for thin sheet metal with a thickness of less than 2mm and large area products, such as computer cases, machine casings, etc. It can not only cutting the sheet metal, but also can do forming processing.it will be in very high efficient for the high quantity features,such as the small hole and flanging.
laser cutting
With the laser cutting process occurred,more and more product cutting processes are being replaced by laser cutting, especially with the fast laser cutting machine power updates and significant cost reductions. Currently, lasers can be used to cut carbon steel, galvanized sheet, stainless steel, aluminum, and have 3D cutting capabilities. A cutting machine with a capacity of 15,000W can cut up to a maximum thickness of 40mm. ,Currently, the tolerance for laser cutting is generally+/-0.2mm, for the lasers have beam diameters, Plasma cutting: It is also used to cut thicker plates, but due to the conical shape formed by the plasma flame, there will be a large slope in the cut product edge.
flame cutting
We can also provide other cutting methods, such as flame cutting, which is generally used for thick plates, usually over 20mm, and for products with low tolerance requirements. If there are size requirements, the cut products must be precision machining again. This process advantage is can operate in outdoor and the machine is very simple, easy to move.
Water jet cutting
Water jet cutting: Water jet cutting is a special cutting process that has absolute advantages for materials that cannot be heated. We served a French customer who used 316L stainless steel in the paper industry. The customer specified that water jet cutting must be used to prevent the cutting edge from changing its composition due to thermal cutting, which will lead to corrosion, sometimes for some parts, in order to control the distortion,we will consider by water jet cutting too.but the cost is a little expensive than laser cutting.
linear wire cutting
Linear Wire cutting is not only used in the mold industry, but sometimes the holes or gaps in some sheet metal parts cannot be cut by laser or mold punching. Wire cutting can play a good role. Although the speed is slow, some factories equipped many machines. If dozens or even 100 machines are processed together, the efficiency is still considerable. Even for some products that require machining, we also use wire cutting to obtain products with very high surface quality after vibration grinding,, At present, the mold industry with high requirements adopts slow-speed linear cutting, with an accuracy of 0.005mm. But the cost is very high.
Bending:
Bending is pressuring deformation processing on sheets metal parts to obtain the desired shape. Currently, we provide mold forming and CNC bending machine processing, which work together to meet customer requirements. Sometimes, when CNC bending machines cannot bend the position with hole or gap , we have to use molds to bend. usually bending machines are suitable for multiple processes and products with larger lengths, using a punch press mold can result in high and cumbersome mold costs. therefore punch press molds are suitable for single processes, For products with large quantities and small lengths, the forming process will involve some material rebound, so we either press excessively or prepare fixtures for inspection to ensure compliance with customer requirements,and shaping the parts if need.
Riveting:
Riveting is a processing that connects two base materials through pin type rivets, and pressure the rivets to deform to firmly connect the two products. We purchase rivet nuts according to customer requirements and assemble them onto stainless steel polished pipes for door handles. Also There are very common PEM fastener, the rivet is very simple for thin sheet metal parts get the thread connect features.
Stretch/drawing:
Stretching is very common in sheet metal parts, such as products in the shape of metal pots, water cup liners (water expansion), and now new energy battery shells are generally stretched by molds on the sheet metal. There are high requirements for materials and molds, and some stainless steel needs to be annealed continuously to relief stress and prevent burst, And annealing treatment is required after forming, otherwise residual stress will cause cracking,
Flanging:
Flanging is also a type of pressure deformation. Some materials are thin, slightly flanging them over to machining some threads can solve the functional problems of the parts effectively. and it will save a lot of materials. It also belongs to stretching, but generally the shape obtained is circular and requires an independent mold
Spinning
Spinning is a special method of processing thin plates. A tool is used on a machine similar to a lathe to hold the thin plate and deform it with a spinning tool to the shape of the inner liner, forming a product similar to a cylinder. Currently, many handicrafts and wine vessels use this process, and many pots and cans in the Middle East are produced using this process.
Welding:
Welding is a process of combining two metal parts through local heating. The temperature at the local point can reach 4000 to 6000 degrees. Currently, there are gas welding, arc welding, laser welding, friction welding, TIG welding, butt welding, stud welding etc., which are used in different situations. Welding requires develop the corresponding welding processes to ensure the welding quality, now the robotic welding machine can replace the manual operation, we can get consistent welding line quality . the selection of appropriate welding materials, appropriate post weld treatment, which is very important for the quality of the weld joint, In addition, welding is easy to thermal deformation, so shaping and develop the special welding fixture and even machining is necessary to ensure the dimensional tolerance required by the customer.
