Clinching, a cost effective solution

The clinching process is a method of assembling sheet metal without welding or fasteners. With this joining technique, metal parts are deformed locally without the use of any consumables.

Multiple materials, with different individual thicknesses can be assembled at the same time based on this cost effective, fast and clean process: steel and stainless steel, aluminium and/or non-ferrous materials. Coated and painted sheet metals can also be joined together without altering the surface finish.

Our RIVCLINCH® clinching machines are very simple to use and can be easily included in the production processes. Only 6 bar/87psi is required to use our portable, standalone or modular clinching equipment.

Compared to traditional joining methods such as spot welding, riveting, screwing or gluing, clinching presents different characteristics including low production costs, little preparatory work, safety and environmentally friendly, reproducibility and durability.


What are the main advantages of clinching?

Most of our customers have switched from traditional joining methods as welding to clinching to solve their technical issues, reduce their production costs, speed up production, or solve their environmental or safety issue.

    Economic

    Efficient

    Ecological

  • No consumable items
  • Very low power consumption
  • No cooling or electrical installation needed
  • Short cycle times (under 1 second)
  • Low maintenance cost
  • No specific skills required
  • Very good strength and joint reproducibility 
  • No risk of corrosion 
  • Air tightness
  • No damage to coating and no burn off
  • Interim layers or film or adhesive can be incorporated in most case
  • No thermal load on joining zone
  • Ensures safety to the users


  • Low energy use (20 times less electricity consumption than welding)
  • No fumes, no sparks, no thermal damage
  • Quiet, simple and fast
  • No pre / post treatment required, 
    • e.g. no pre-cleaning or subsequent removal of spray deposits around the joint


"When you have the choice clinching is always the best solution." Automotive customer.

How does clinching work?

You may already have heard of clinching as a mechanical interlock connection process, or a cold welding process. 

Clinching requires only the sheet metals to be assembled. No consumables such as rivets, glue, screws or welding are needed to assemble the metal parts.

During the clinching process, the metal sheets are plastically deformed. A special punch and die causes the creation of the interlock between the sheet metal layers.

The punch is moved with the required force depending on the thickness and the strength of the materials to be joined and the die is fixed.


Deformation of the sheets by compression between punch and die:



1) After being placed, the materials to be joined are firstly forced into the die with the punch.

2) As soon as the lowest material is resting on the die anvil, it starts flowing sideways under the pressure being exerted by the punch. The blades are pushed outwards.

3) The punch is then returned to its starting position by the operator or by a pneumatic timer which removes the force.

4) The metal sheets are now joined and can be removed. The blades are pulled back together by a spring.

5) The result is a resistant clinch joint.


A classic RIVCLINCH® clinch joint is created in less than a second. Depending on materials and conditions it can reach 100 to 300ms. 

There is absolutely no specific skills required to use our clinching equipment. It is actually very fast and simple to clinch. 

The RIVCLINCH® joining system may be adapted to existing presses or used in custom-built machines. Both single points and multiple points can be set at the same time. An integration of the clinching system into manual machines, robots and stationary tools is feasible.

Clinching is used to join steel and stainless steel materials as well as aluminium and other non-ferrous materials in a cost-effective and environmentally friendly manner.

What can I clinch?

Typical materials which can be clinched include:

  • Low carbon and micro-alloyed steels
  • Zinc-coated, organic coated and pre-painted steels
  • Stainless steels
  • Lightweight materials, such as ductile aluminium alloys


Dissimilar material combinations can also be clinched, for example steel to aluminium.



Standard
Special 
Material of sheets
Aluminium
Copper
Mild steel
Stainless steel
Up to Grade 304
(Tensile strenght 500 MPa)
Total thickness of sheets (T)
1 to 6 mm 
10 mm Steel
18 mm Copper
Cycle time
0.4 to 1.2 sec
Diameter of die (D)
3 to 8 mm 
1 to 10 mm 
Shear strenght
1 to 8 KN
Joining Force (F)
25 to 75 KN
100 kN (single tool)
300kN (multiple tooling) 


As the joint is made by local plastic deformation of the sheets, it is essential that the materials have sufficient ductility to avoid cracking. Harder materials, such as stainless steels, are normally clinched with semi-piercing tooling. 

The automotive industry, for example, is driven by weight-reduction, and manufacturers are moving towards thinner, stronger materials. This may affect the material's ductility and reduce its suitability for clinching. Therefore further optimization of the process cycle and developments in punch and die design can be realized.

RIVCLINCH® joint point geometry

The heart of our expertise stands in the clinching joint. 

Depending on the clinching tool selected, the resulting joint will be either round or rectangular.  

Round joint SR (Spot Round)

  • The SR round joint without cutting trough the material, is just a deformation.

  • This joint is water and gas tight. Consequently it protects the coating better and provides high corrosion and fatigue resistance.

  • This joint is also aesthetically pleasing.

Rectangular joint ST (Spot Rectangular)

  • The ST rectangular clinch joint is the product of a combined cutting and deforming process.

  • It is primarily suited to multi-layer (up to 5 and more), harder metals such as stainless steel and wider range of thicknesses.
questions

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