Sheet metal process analysis
Sheet metal is a general term for the process of cutting, punching, folding, welding and other cold processing of metal sheets (usually less than 6mm thick) to make the required prototypes or parts.
It is one of the most widely used, lowest-cost and most flexible molding methods in modern manufacturing. From electronic equipment casings to aircraft skins and automobile bodies, they are all inseparable from sheet metal technology.
The sheet metal process has the advantages of high strength and light weight. Through bending, stamping and other processes, the structural rigidity can be greatly improved without increasing the plate thickness.
At the same time, it has low cost and high efficiency. The raw material plates are cheap and suitable for mass production. For small batches or prototypes, it can also be quickly completed through laser cutting and bending without the need for Mold Manufacturing.
The material selection is very wide, and cold-rolled plates, galvanized plates, stainless steel, aluminum plates, copper plates, etc. can all be processed.
In addition, sheet metal parts are easy to assemble and repair. They can be combined through welding, riveting, threaded connections, etc., and they can also be easily replaced or reshaped when damaged.
A typical sheet metal part usually goes through the following steps:
① Design and draw. Use CAD software to draw 3D models and convert them into expanded drawings.
② Calculate the size. Apply empirical formulas such as bending coefficient and K factor to determine the blanking size of the flat plate.
③Blanking. Cut the sheet into the desired shape by laser cutting, CNC punching or shearing.
④Molding. Mainly bending, the flat plate is bent into a three-dimensional shape through a CNC bending machine; sometimes it also includes stretching, stamping and reinforcement, etc.
⑤Connect. Assemble multiple parts by welding, riveting, riveting screws, etc.
⑥Surface treatment. Spraying, electroplating, anodizing, wire drawing, etc. to meet rust prevention and aesthetic requirements.
⑦Inspection. Check whether the dimensions, angles, flatness, etc. comply with the drawings.
Cold-rolled plate (SPCC): has good surface quality and high dimensional accuracy, but is easy to rust and needs anti-rust treatment. It is the most basic material for sheet metal and is widely used in chassis, cabinets, brackets, etc.
Hot-rolled plate (SHCC): lower price, but has rough surface and oxide scale. It is generally used for structural parts with low surface requirements.
Galvanized sheet (SECC/SGCC): The substrate is a cold-rolled sheet with a galvanized surface and a certain anti-rust ability. It is often used in distribution boxes, computer cases, etc.
Stainless steel plate (SUS304): It has strong corrosion resistance, high strength and bright appearance. It is used for medical equipment, food machinery, outdoor equipment, etc.
Aluminum plate (5052/6061): light weight, good thermal and electrical conductivity, not easy to rust, used in radiators, electronic casings, aerospace parts, etc.
