Pressure forming is a material-forming process: plastic deformation of die stock materials with metal efflux limited by size of the stamping area.
The stamping process consists of the material shaping without metal removing. High-quality accuracy of products is ensured by good performance.
All operations are performed by utilizing special tools – dies that have various designs depending on their purposes.
Generally dies consist of cover half and ejector half, bearing working portions (die set), the approach of which ensures the deformation of the stock material placed there between.
Stamping dies portions are attached to the mold.
The cover half is fitted to the platen and the ejector half – to the slide of a press (operating motor).
The operating units of the stamping dies re made of instrument steels; in case of low volume press die forging of the parts, made from aluminum and other soft materials various substitutes can be used (plastic, pressed wood, etc.).
There are two main types of die forging: sheet-metal forming and die forging.
Two opposite processes can occur during the deformation depending on the temperature and speed conditions: strengthening caused by the deformation and loss of strength due to crystallization.
Accordingly to this cold and hot deformation are distinguished.
Cold deformation occurs at a temperature below the temperature of re-crystallization and is followed by the hammering harden.
Hot deformation occurs at a temperature above the temperature of re-crystallization.
Metal strengthening (hot-cold work) is also achieved during hot deformation, but it is completely removed during the re-crystallization.
Metal ductility is more high in the process of hot deformation and strain resistance is approximately 10 times less than in cold deformation.
Sheet-metal forming can be divided into types BY TYPE of the equipment used:
Forming in tool stamps;
Forming with elastic fluids;
“Poltavaspetsmontazh LLC” offers services of metal products manufacturing by method of cold stamping in instrumental stamps, which is carried out without metal preheating.
In capacity of material we use metals in the form of tapes, sheets, strips, 2 -10 mm thick and rods made from soft carbon steel and high hardness steel, non-ferrous metals and their alloys.
Metal is formed on the mechanical presses by force of 3, 6, 10, 43, 63, 100 tons.
We use the present method for manufacturing of both, flat and roll-formed products.
The parts manufactured in accordance with method of sheet-metal forming are characterized by absence of significant difference in the wall thickness and the thickness of the starting stock.
If three-dimensional parts are manufactured in accordance with the method of sheet-metal forming the starting stock usually undergoes significant plastic deformation.
This circumstance results in requirement of rather high ductility of the starting stock.
PROCEDURE FOR SHEET-METAL FORMING INVOLVES THE FOLLOWING OPERATIONS:
Shearing operation is the operation of metal processing with pressure which results in complete or partial separation of one part of the work piece from the other one. The shearing operation includes:
Cutting is a segmentation of work piece in open circuit by method of displacement on a special-purpose cutter (guillotine shear) or in the dies.
Blanking is the operation of complete separation of the product from the starting stock in close circuit by method of displacement.
Punching is a process of a hole or collar formation by method of displacement followed by withdrawal of metal portion to waste.
Operation on form change is the operation of metal processing with pressure results in form change of the work piece by method of plastic deformation. The above mentioned operation includes:
Bending is the process of formation or change of angles between the parts of the work piece, or work piece curved shaping.
Stripping is the procedure of tubular body formation from any plate or hollow billet parent sheet.
Drafting in stamping die is the process of size reducing in the cross-sectional area in the part of the hollow billet by mean of simultaneous instrumental proceeding along its entire perimeter.
Flanging is the process of board forming in the inner outline of stock material or product.
Bulge forming is formation of the relief in a parent sheet due to local elongation with no change in the metal thickness.
“Poltavaspetsmontazh LLC» has the ability to perform bending operations on shape changes by bending process.
Cost of components is mainly consists of the material cost and cost of material manufacturing.
In case of sheet-metal forming the average cost of metal consists 80-85% and the cost of manufacturing – 15-20%.
A variety of forming methods, the use of stamping dies of different design (specific and universal), and the use of the appropriate materials for their manufacturing provide a cost-effective production of the same parts at any output.