Can laser welding save time and money?

ANY FABRICATOR tired of wasting valuable time and money on conventional welding methods should investigate laser welding. Often, the high heat input of conventional welding causes discolouration of the workpiece, resulting in time-intensive reworking. In contrast, laser welding’s low heat input means fabrication shops can produce high-quality, immaculate seams without any need for secondary operations. In the experience of Trumpf, the process not only saves time, but money. 

There are five common indications that a laser is the right tool for a welding application: when a lot of time is spent welding one component; when a facility is using too many grinding disks (on burdensome rework); when components must meet a high standard; when component accuracy requirements are high; and when there is a desire to implement complex seam geometries. Any fabrication shops witnessing any of these indicators should take a closer look at laser welding.

A fraction of the time
In the first instance, laser welding has a far greater process speed than conventional welding. For example, the MAG welding of a 600mm long weld seam in 1mm thick structural steel will take about 60 seconds. Lasers can complete this job on the same machine in as little as four seconds, allowing manufacturers to increase their profit margin or reduce component costs for customers.

The elimination of post-processing is another advantage with laser welding, where high-quality seams mean little or no finishing is required. As a result, the process is ideal for parts where visibly attractive seams are necessary. 

Lasers also have the ability to control the energy input of a welded part in a precise way. Components therefore have far lower heat input compared with arc welding which, in turn, means that laser-welded parts rarely distort, eliminating the need to level the component afterwards.

Design freedom
As a point of note, laser welding offers unlimited processing freedom. Lasers allow fabricators to implement a large number of complex seam geometries, such as lap seams or a concealed T-joint. Even if specific areas of the component require processing and are only accessible from one side, users can position and guide the laser beam along any seam geometry.

As another advantage, there are hardly any material restrictions when it comes to laser welding. The minimal melt with short, controllable duration means that a laser welding system is able to join materials otherwise impossible.

In terms of the process, a laser beam can join metal in different ways – from instantaneously creating fine weld points of just 1 mm in diameter, to producing deep-welded seams stretching over several metres. It is also possible to combine the laser with conventional welding processes. 

System selection
Thanks to the versatility of laser welding, the process is perfect for applications that extend from high-speed trains and automotive gearboxes, to airbag holders and pacemakers. 

Trumpf has a comprehensive range of systems for many applications and budgets. The TruLaser Cell 1100 is a beam guidance system for production line integration that can deliver the endless welding of any seam geometry on strips, tubes and profiles, as well as the welding of rotationally symmetrical parts. The TruLaser Cell 3000 is suitable for both 2D and 3D welding and cutting, along with laser metal deposition (LMD), while the TruLaser Cell 7040 is a modular machine offering greater production flexibility. And the TruLaser Station 7000 is a compact 3D laser welding system for small assemblies. 

There are clearly many disadvantages when it comes to conventional welding methods. More often than not, rework is required that consumes valuable time. For this reason, increasing numbers of fabricators are choosing to adopt laser welding systems.

David Sandner is lead management and marketing, Trumpf Ltd
uk.trumpf.com
Tel 01582 725335