With the progress of technology and the improvement of high-performance equipment, the complex processing technology of sheet metal fabrication is becoming more and more mature.
Sheet metal processing is widely used in all walks of life. Whether it is electronic and electrical appliances or automobile industry, communication engineering or medical device industry are inseparable from sheet metal.
Table of Contents
Sheet Metal Fabrication Techniques
Sheet metal fabrication technology is a comprehensive cold processing technology for sheet metal processing.
With the increasing application of sheet metal parts, sheet metal processing technology has become a very important part in the process of product development. Designers need to master the process characteristics of sheet metal.
On the one hand, it can meet the requirements of product function and appearance, on the other hand, it can simplify the model and simplify the production process, so as to achieve low production cost and high production efficiency.
The following mainly introduces 24 common processes in sheet metal fabrication.
Blanking
Laser cutting machine or punch machine processes materials according to programming files. Among them, laser cutting machine can meet the cutting of parts of various shapes, and punch machine has advantages in batch processing.
Bending
According to the marked dimensions of the bending drawing, the workpiece is bent and formed by the press brake machine. The bending die is divided into upper die and lower die. Different shapes need different dies. The accuracy of the bending dimension is determined by the quality of the die.
Forming
Die is used on ordinary punch press or other equipment to make the workpiece directly into the desired shape. Most of them are stamping forming, which is widely used in the field of automotive sheet metal and electronic products.
Tapping
According to the bottom hole of the workpiece, the corresponding internal thread is processed on the workpiece. Tapping has requirements on the plate thickness – too thin is easy to slip.
Counterbore
Taper holes are machined on the workpiece. In order to have a good appearance, there is no exposed screw head, and the workpiece is mostly installed with counterbores.
Press riveting
The press riveting nut, screw or nut column and other fasteners shall be firmly crimped on the workpiece by punch or hydraulic press. The bottom hole shall be opened on the workpiece in advance for press riveting, and the fasteners shall be pressed on the workpiece during bending, which can reduce the workload of welding and protect the appearance of special workpieces.
Punch convex hull
Punch or hydraulic press use molds to make the workpiece form a convex shape, such as punching louvers. Different molds are required for different shapes. On the whole, it has beautiful appearance and strong functionality.
Printing
Characters, symbols or other shapes are punched out on the workpiece by using the die, mainly including the company name, company logo, company website and company contact number. Its advantage is that it can be permanently retained with the workpiece.
Punching mesh
The mesh holes are punched out of the workpiece with a die on an ordinary punch or CNC punch. The mesh plate on the workpiece can play the role of beautiful decoration and meet the function of heat dissipation.
Deburring
The rough edges on the workpiece surface can be removed by grinding machine, file and other tools to make the workpiece processing place smooth and flat, so as to prevent cutting and scratching.
Argon arc welding
The connection between workpiece and workpiece is welded at the edge or joint of workpiece by argon arc welding machine, which is divided into intermittent welding and full welding. It needs to be clearly marked on the drawing. Argon arc welding has stable arc combustion, high production efficiency, small welding deformation and convenient operation and observation.
Planting welding
The planting welding screw is firmly welded on the workpiece with a planting welding gun. Planting welding is often used on the workpiece with small stress and requirements for the outer surface of the workpiece to ensure the beauty of the workpiece.
Welding and grinding
Using grinding machine, file and other tools to make the welding scar of the workpiece smooth and flat, a better forming surface can be obtained, and the adhesion can be increased for the subsequent spraying of plastic powder.
Pretreatment
After the workpiece is processed, before painting or powder spraying, the workpiece shall be degreased and derusted with electrolytic solution, and the coating (such as phosphating film) on the workpiece surface shall be added and cleaned to increase the adhesion of subsequent plastic powder spraying.
Dust scraping and grinding
Make up the defects on the surface of the workpiece with atomic ash, such as welding gaps or pits, and polish the surface of the workpiece after scraping with a flat grinder or abrasive cloth, so as to increase the parallelism and appearance beauty of the whole workpiece and further increase the adhesion of sprayed plastic powder.
Wire drawing
It is a kind of texture treatment on the workpiece surface by using wire drawing machine and abrasive belt to increase aesthetics and market demand. It is mainly stainless steel surface treatment.
Polishing
Use polishing equipment to polish the workpiece surface to increase aesthetics and surface smoothness, mainly stainless steel surface treatment.
Heat treatment
In order to improve the hardness of the workpiece, the final purpose of heat treatment is to improve the mechanical properties such as hardness, wear resistance and strength of the workpiece.
Fuel injection
Spray the paint evenly on the surface of the workpiece with a spray gun, which is convenient, fast and easy to use.
Plastic spraying
Spray the powder evenly on the workpiece surface with a spray gun and bake it in an oven. The plastic sprayed workpiece has better wear resistance and corrosion resistance.
Blackening treatment
Chemical surface treatment is a common means to produce an oxide film on the metal surface to isolate air and achieve the purpose of rust prevention.
Silk-screen printing
The special ink penetrates through the special grid to form words or patterns on the surface of the workpiece. The silk screen printing has a wide range of applications, durable colors, fast and convenient operation.
Laser marking
Surface treatment using optical principle; The laser beam can engrave permanent marks on the surface of the workpiece, and the shapes are various.
Conclusion
With the rapid development of industrialization, the processing and manufacturing of sheet metal parts is also developing towards intelligence. As the coat of mechanical products, the quality of sheet metal parts also plays an important role. In order to ensure that the surface forming of sheet metal parts meets the requirements, it is necessary to ensure the quality from two aspects: surface quality and internal quality.