Stamping

Several types of presses, mechanical, pneumatic or hydropneumatic, can be used to stamp parts in small, medium or large series. Stamping is a technique used in a wide variety of applications where many parameters are involved. 

 

As with our presses for assembly, stamping, bending and riveting, EMG designs presses that can be modified to adapt to the different types of production as well as to the safety and comfort of the operator at his workstation by taking into account each of the specific parameters of its customers. 

 

Cold stamping with mechanical press

 

Cold or hot mechanical stamping is a process for forming parts that requires machines such as a mechanical press and suitable tools (ies, punches...). The principle is based on the plastic deformation of the material (usually a metal), which consists of stretching or shrinking the sheet to obtain the desired shape.

 

A distinction is made between cold stamping - that carried out with the presses offered by EMG -, which is carried out at room temperature, and hot stamping, which is carried out with a part heated to about 800°C for mild steel.

 

Cold stamping is the most widely used technique for large or very large production runs for parts that simply require a powerful one-sided action. Indeed, the cost price of the operation performed is extremely low considering the very large number of parts produced associated with a very short manufacturing time. The implementation of this type of tool is quite fast and allows the production of parts as soon as the tool is installed and adjusted on the press table.

 

Cold stamping can be done with a pneumatic press (with pressure up to 6 tons), or a hydropneumatic press (with pressure up to 100 tons). However, for large quantities, mechanical presses are more suitable. Their striking power and their speed of execution allow them to reach a much higher productivity than pneumatic and hydropneumatic presses.

 

The adjustment of many parameters on the press allows to adapt the tools (punches, dies...) necessary to the production process and to obtain the exact pressure which will limit the cases of rupture on all or part of the surface of the stamped parts. 

 

The depth of the gooseneck, the headroom, the lowering speed and the stroke are important parameters for which we can provide you with details when you ask yourself which press to choose for stamping parts made of different materials with varying strength and elasticity. 
 
We adapt our machine tools so that your stamped objects will take the desired shape, thickness and diameter with a minimum of scrap. Easy to operate, our presses are robust and guarantee impeccable production, even for large-scale production.

 

EMG mechanical presses can be equipped, at the customer's request and according to specifications, with any special adaptations required to optimize production.

Some examples of possible adaptations on EMG presses:

We can adapt our presses to your activity by making the stamping process as efficient as possible while providing maximum comfort to the operator at his workstation:
 

  • A lower and/or upper ejection system (pneumatic or mechanical) to release the part or the part that has just been manufactured.
  • A system for lubricating production at each press stroke.
  • A blowing system in the tool.
  • A material transport system before and after cutting.
  • A cutting system for scrap at the exit of the tool.
  • An automatic screen system that physically protects the operator during typing.
  • An evacuation control of the manufactured parts or the produced scrap.
  • Specially designed protections for the geometry of the manufactured parts.
  • Intelligent protections that guarantee the safety of operators and automate the departure of the press.
  • The possibility of varying the speed of the slide's movement during striking. Once the speed has been selected, it is fixed during striking.
  • The adaptation of a PLC that will be able to manage the press according to its environment in a complex production line.

 

It is also possible to vary the speed at which the ram moves before striking or to adapt a PLC that will be able to manage the press according to its environment in a complex production line. We can also meet your specific needs by designing a special machine and custom-made equipment (manual presses & mechanical eccentric presses) for you.

 

The advantages and disadvantages of sheet metal stamping.

● Advantages of sheet metal stamping in the automotive industry

Sheet metal stamping is an essential process in the automotive industry. Precision and speed of production are essential. The main advantages of press stamping are as follows:

- Lower production costs: Using mechanical or hydropneumatic presses, it is possible to produce parts in large series at a low unit cost.

- High precision: Tools such as dies and punches can be used to create complex shapes with excellent quality and uniform sheet thickness.

- Material flexibility: Stamping can be applied to different types of metal. Mild steel, aluminium and stainless steel can all be deep-drawn, depending on the project requirements.

- Process optimisation: the speed of modern machines means that the requirements of high-volume production lines can be met.

● Drawbacks and limitations of sheet metal stamping

Stamping nevertheless encounters significant constraints to be aware of, such as wear and tear on dies and punches which are subjected to high pressure, the need for additional technology to overcome the limitation concerning the stamping of certain geometric shapes and the potentially high cost concerning the design of specific tools.

 

The key stages in the sheet metal stamping process  

The preparation and design of a sheet metal stamping operation is based on a needs analysis, during which the specifications of the part (shape, thickness, materials) are defined, and the possible design of the stamping tools, during which parameters such as the strength of the sheet metal or the gooseneck depth of the press must be taken into account.

The choice of press will depend on the material and the volumes to be produced. At EMG, we offer :

- Mechanical presses for their power and ability to produce large quantities of parts,

- Hydropneumatic presses for ultra-precise control up to 100 tonnes,

- pneumatic presses for pressures of up to 6 tonnes.

 

The different phases of the sheet metal stamping process

There are four main stages in the sheet metal stamping process: fixing the sheet, forming, ejection and, finally, quality control. Once the sheet has been positioned on the die, it is pressed into shape. The pressure is determined according to the material to be stamped and the press used. The parts produced can then be ejected using a pneumatic or mechanical ejection system. Although our presses are designed for optimum results, quality control ensures the conformity of the parts or series of parts produced.

 

Recent applications and innovations in sheet metal stamping

Stamping operations are often necessary in the aerospace industry. This technique meets the precision requirements of parts whose main properties are strength and low weight. EMG's mechanical and hydropneumatic presses, equipped with high-precision tools, enable complex components to be produced to the exacting tolerances required in this cutting-edge sector.

Stamping presses are an integral part of today's technological innovations. In fact, at EMG, we offer special designs to meet our customers' requirements, for example for the creation of a production line into which a press can be inserted. Whatever your application, our technical teams will help you choose your press.