Definition of mechanical welding
Mechanical welding is a common working technique in the metallurgy sector. This work method consists of assembling metal parts of different shapes and thicknesses by welding in order to obtain a mechanically welded assembly. Its use in boilermaking is mainly intended for the production of complex superstructures for its many advantages.
Mechanical welding requires the use of high-performance equipment to facilitate the assembly process. In the category of complementary and useful processes for mechanical welding, we can cite cutting, stamping, shearing, bending, punching, bending, etc.
Generally, steel, stainless steel and aluminum are the main metals worked in mechanical welding because of their popularity but also because of their properties. Titanium, copper and its alloys are metals used with this working technique only in specific sectors of activity.

What is a mechanically welded structure?
A mechanically welded structure with a mainly mechanical use. This is the assembly of various metal parts between them through welding. Metal parts are made from sheets, profiles or tubes. Thus, it is common to see mechanically welded assemblies with these different part profiles.
Being an assembly or a sub-assembly, the mechanically welded structure has the advantage of being manufactured individually or in series, whatever its size. Because of its method of execution, it is popular to manufacture large mechanically welded structures in boilermaking.
The complexity and scale of certain mechanically welded structures require a detailed digital representation. This is why the mechanically welded assemblies are reproduced on computer-aided design (CAD) software. Commonly in the metalworking/boilermaking industry, skilled people use SolidWorks software to represent parts.
A mechanically welded assembly being commonly a part having to support heavy loads, it is important to simulate the solidity and the resistance of the parts which it is possible to do on this type of software.
An efficient manufacturing technique
Mechanical welding allows the manufacture of complex parts by their shapes, their positioning and the harmony of the materials while guaranteeing a high precision of assembly. Unlike cast parts, a structure made by mechanical welding will obviously be less expensive but also lighter and more stable while guaranteeing robustness.
In addition to being a high-performance technical process, mechanical welding requires extreme precision to ensure the reliability of the part in terms of its load capacity, its tolerance, its location in the environment, etc. Certain deformations of a few millimeters/centimeters can reduce the reliability of the mechanically welded structure. High precision in this technique is essential for efficiency and reliability, thus ensuring the safety of the entire manufactured part.
This is why this manufacturing method is commonly used in demanding fields of activity where the achievements are generally medium and large in size:
- Industry
- Naval
- Railway
- Nuclear
- Automotive
- Food industry
- Aeronautics
- Heavy machinery (agricultural, industrial)
- Indoor/outdoor construction
- Renewable and Fossil Energy
- And so on


The advantages of mechanical welding
Mechanical welding is a process appreciated by manufacturers since it provides many advantages and is used in many situations.
First of all, a mechanically welded assembly is produced in a short time, thus justifying its economic advantage compared to other processes. This speed is due to the specific equipment during the process and by the assembly of already formed and/or prefabricated elements.
Thanks to mechanical welding, it is possible to manufacture any type of work, from the simplest to the most complex. This assembly technique has few limits in terms of structure and thickness.
The solidity of mechanically welded structures is recognized and necessary in its mechanical function. This resistance is associated with stability and rigidity, thus making it possible to support heavy loads.
Finally, the durability of the mechanically welded structures is established thanks to the welding which does not allow dismantling the various assembled elements. This junction ensures solidity for complex and imposing structures. In addition, assembly by welding has the advantage of being able to weld metal parts with large thicknesses.
Welding processes for assembly
As for the welding processes, according to the technique used in the assembly by mechanical welding, they are categorized into sub-parts:
- Mechanical welding
- Electric welding
- Explosive gas welding
- Aluminothermic gas welding
Generally, TIG, MIG and MAG welding are the welding methods used in mechanical welding for their many advantages (mechanical and electrical welding).
TIG (Tungsten Inert Gas) welding
For precision mechanical welding work, it is recommended to use TIG welding. Indeed, it is possible to use this technique on thin sheets to obtain an elegant and high quality result. However, this technique is slow on thin layers. Regarding the metals tolerated with this technique, we can cite steel, stainless steel, aluminum, titanium and copper.
MIG (Metal Inert Gas) and MAG (Metal Active Gas) welding
MIG and MAG welding is recognized for its speed and regularity, making this method an ideal choice for mechanical welding. With its excellent performance in sheet metal work, it is ideal for assembling mechanically welded structures.
Due to its advantage of depositing more material than TIG welding, it is designed for welding very thick sheet metal guaranteeing the rigidity of mechanically welded structures. And, its use is intended for steel, aluminum and stainless steel which are the main metals used.
IDRA Global Industries, ideal partner in mechanical welding
IDRA Global Industries, an industrial boilermaking company, has significant experience in mechanically welded works thanks to highly qualified personnel, an integrated design office and know-how in many fields of activity.
With many skills, qualifications and high-performance equipment, IDRA Global Industries has all the resources necessary to carry out your complex mechanically welded projects. The company has a design office and methods to support you in the design and prototyping/technical testing of your boilermaking projects.
Collaborating with major French and foreign contractors, we are able to meet requirements and specifications by optimizing our material and human resources to design high quality parts.
We can manufacture mechanically welded units individually, in small series or in large series according to your needs and this in many sectors.
Thus, as a boilermaking company in Nantes, we have trusted partners for finishing work (powder coating, painting, surface treatment, etc.) to reduce intermediaries during a commercial collaboration.
Located near Nantes, Angers and Rennes, IDRA Global Industries is available to meet your mechanical welding projects.