3 good reasons for squaring tubes before welding

Squaring of tubes before welding can be interesting for various reasons, and especially for automated or orbital welding applications. Only thin tubes with wall thicknesses no bigger than 3mm are concerned, which generally have to be welded by simple fusion.

Simple fusion means that two workpieces have to be butt-welded without any seam without any gap and without adding wire. This is the most important fact: the surface conditions of the workpieces have a direct impact on the quality of the assembly.

Here you can discover 3 reasons that explain you when squaring of workpieces is necessary before welding:

#1 Better surface quality

Squaring of tubes is generally done with very sharp HSS blade: the edge breaking tool creates one only chip (forming) which provides a very precise RA surface quality.

Certain industries require high quality finishes like squaring preparation. This is for example the case in the semiconductor fabrication, the pharmaceutical or biopharmaceutical market. These applications need squaring, even if the tube has been cut perfectly straight and perpendicular with an orbital cutting machine.

Using orbital cutting machines provides you with the highest quality cuts but they form tiny scratches due to the use of the blade. This is not acceptable for very high-end applications, even if you cannot see these scratches with the human eye. Parameters such as rotation speed, combined with the travel speed - have a certain influence on the final result. This surface quality is largely good enough for most applications, such as in the food industry for example.

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#2 Perpendicularity quality or presence of scratches

Other aspects linked to the quality of cutting and the perpendicularity or presence or scratches can also be corrected. In fact sometimes cuts are made with abrasive tools or saw bands. In these cases the cuts are not precise enough for an automated welding operation. A squaring machine can also help to complete an approximate cut.

#3 Bringing in conformity after a cut by distortion

On site and when it comes to maintenance, tubes often need to be cut directly in an installation in order to be replaced. This is often done with roller tube-cutters. This is a tube distortion process that does not create any chip, just a small quantity of metal dust.

But, tubes cut by distortion cannot be welded without bringing them to conformity by squaring.

All our squaring machines (besides the two versions with a concentric clamping system) are compact and more or less light (depending of the size). They can be used anywhere on site!


Some more aspects to be considered about squaring tubes

  • The squaring machines for “on site use” have been designed with a shell clamping jaw system; one set of jaws per tube diameter is necessary. Any other concept would be too cumbersome.
  • But there are also squaring machines for prefabrication to be used in workshops where tubes can be transported towards the machine. In this case, the concentric clamping jaws can cover more diameters without the need of specific jaws. This kind of fixed machines is to be preferred for workshop applications.
  • Last aspect will be the preparation of T-pieces. In fact sometimes the surface is altered or a part of the piece might have been cut under bad condition. In this case, short jaws are necessary for every diameter. As you can understand, there are a lot of different applications to be considered.
  • More and more squaring machines, and in particular our DC range, are equipped with battery driven drilling machine motors that can easily be removed and used for other tube preparation machines. This increases the number of functions and applications which enhances the productivity. This is our DNA whilst developing our machines.

This is a very strategic item: Mastering the tube preparations in order to master perfect orbital weldings. This is the reason why we develop machines for tube preparation as well as welding equipment. Due to this strategy you can master the whole production line and realize high quality welds with an up to 100 % repeatability quote! Don't hesitate to contact our teams, they will be happy to help you with your project!


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Écrit par
Frédéric Legrand

CEO and founder of AXXAIR