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 - 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 1472°F 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 forming can be done with a pneumatic press (with pressure up to 6.6 tons), or a hydropneumatic press (with pressure up to 110 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, 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 ability to vary ram speed before striking. Once the speed has been selected, it remains 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 of movement of the ram before the striking or to adapt an automaton which 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. 

 

Advantages and disadvantages of sheet metal stamping

● Advantages of sheet metal stamping in the automotive industry

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

- Lower production costs: Thanks to the use of mechanical or hydropneumatic presses, parts can be mass-produced at low unit costs.

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

- Material flexibility: Stamping can be applied to many different types of metal. For example, mild steel, aluminum or stainless steel can all be deep-drawn, depending on project requirements.

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

 

● Drawbacks and limitations of sheet metal stamping

Nevertheless, sheet metal stamping is subject to a number of important constraints, such as wear and tear on dies and punches, which are subject to high pressure, the need for complementary technology to overcome the limitation of stamping certain geometric shapes, and the potentially high cost of designing specific tools.

 

Key stages in the sheet metal forming process

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

 

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

- mechanical presses for their power and capacity to produce large quantities of parts,

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

- pneumatic presses for pressures up to 6 tons.

 

The different phases of the sheet metal stamping process

There are four main stages in the sheet metal stamping process: sheet clamping, forming, ejection and, finally, quality control. Once the sheet has been positioned on the die, it is pressed into shape. 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. Even though 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 aeronautics 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 tooling, enable the production of complex components while respecting the demanding tolerances of this cutting-edge sector.

 

Stamping presses are an integral part of today's technological innovations. In fact, at EMG, we offer special executions 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 support you in your choice of press.