Welding and multiple-part assembly!

Welding:

As we already know, welding is a fabrication process, used to assemble together metal pieces, by heating and melting them. During the melting process the base metal fuses with the filler material and after cool down you have the finished joint part.

Even though it has become an inseparable process for almost every mechanical engineering, there are many “tricks” of the trade when welding.

In the process of manufacturing quality joint parts, welding engineers must calculate properly the linear extensions and contractions which occur after the cool down. In other words, after the welding seam cools down, the two joint pieces deform in the direction of the weld (pic.1)

This can always cause problems, especially with parts, designed for dynamic exploitation.  So in order to avoid this effect and actually achieve flatness, fabricators and engineers combine skill and knowledge and apply different methods to compensate the shrinking of the weld.

• 1^st method is to restrain the two work pieces and release them after the welding cools down. (pic.2)

• This technique however, leaves tension in the joint and if not well restrained, eventually may as well cause deformations.

Positioning of the work pieces. Calculating the welding distortion and presetting the two pieces accordingly can be very helpful after cool down (pic.3).

• Another variable in the welding process is speed of welding, which directly affects the heat input in both main and additional material, respectively the deformation of the assembly. Higher speed means less heat in the material.

  However, faster welding has its downsides – mainly the possibilities of defaults in the seam.

In order reach quality high speed welding, manufacturers must rely on very skilled welders and/or apply automated welding.

Automated welding is mostly used for large scale identical parts like in the Oil and Gas industry (for pipelines), Automotive industry (robotic welding).  Very often only certain sections are welded automatically, like the circular seams (pic.4) in the pipelines and/or the linear seams (pic.5) of the pipe.

Multiple-part assembly:

To multiple-part assembly we refer to joining work pieces or complete parts by bolted connection, brackets or other type of fasteners.  This process is more unlikely to be automated, since manual labor and hand-on approach is crucial.

Industrial designs for overall plants, installations and equipment, include complex assemblies which are always better to be prepared in manufacturing facility rather than on-site, where the environment is always challenging for the staff. Therefore engineering companies prefer to provide a complete component to their workers on-site.

The best example that comes handy is the steel structures which serves for mounting the plant equipment. Contractors would always prefer to have assembled as much as possible before going to site, so they can save time (pic.6).

Another example is the small-part components, which are later included for larger assemblies and larger equipment (pic.7)

In every case OEMs, Engineering contractors and manufacturers often prefer to have their parts welded and assembled before installing, but instead of investing time and funding for labor and machinery they outsource this function to specialized companies, who manufacture only outer purchases.

At My Euro Steel, OEMs, plants and engineering contractors can benefit from the wide variety of machinery and specialized labor, so they can focus on the importance of their current and future projects. 
In other words, My Euro Steel takes care of quality welding and strong assemblies, while investors focus on their future.