Does laser welding work with tubes?

Yes, tubes are easy to weld with laser welding.  Laser welding is fast and enables neat root passes without leaving a gap.

Aluminum tube with fusion laser welding
laser welded aluminum tube

Why laser welding works well for Tubes 

Laser welding is ideal for tubes because it can do a good root pass in one operation.  Fiber lasers can weld stainless steel, aluminium and steel tubes with wall thickness up to 6mm in one pass.  All the parameters can be controlled repeatably, so once set up, laser welding will deliver exactly the effect you require.

This can include pulsed welding to achieve the TIG “stack of dimes” look.


What is the secret to laser welding Tubes?

A rotary is the best method of laser welding tubes.  This is fast and repeatable.  Our double wobble laser welding head has advantages in most situations, and allows quick optimization of the weaving pattern to get a beautiful and strong weld.

Using a rotary works well for flanges, butt welding, lap welding, and generally welding anything round including load cells.

Laser welding 16 gauge steel tube in a rotary
Laser welding 16 gauge steel tube in a rotary
Neat laser weld on galvanized steel box section
Laser weld on galvanized steel box section

Does laser welding work on box section tubes?

Box sections weld fine with a laser welder.  For aluminum extrusions with square corners fusing is the easiest option.  Simply butt them up and use the autogenous process. 

For rectangular steel tube (box section) the only thing to watch is filling of gaps due to the radius of the tube corners.  If the radius is large, a twin wire feeder is the best method.  This allows the operator’s speed to be set by the wire feeder, while two 0.063″ wires (1.6 mm) feed out and are melted into the weld. 

For larger gaps it is also possible to use a single wire feeder and hold the gun back so it builds up a larger bead, and control the melt pool more like a MIG.  However for box section tubes with a large edge radius the large gap is best welded with our twin wire feeder option.

How to seal round load cells with laser welding?

Load cells can be tubular and are always a prime candidate for laser welding.  Load cells are precisely made and require assembly with good sealing of the cover plate and minimal distortion, which could affect their calibration. 

Laser welding is the ideal process for welding load cell cover plates in position.  This image shows a very fine laser weld done with a rotary and hand held laser welding head.  At only 0.040″ wide, this is a small weld.  However the best machine for this job is one of our popular multi-axis CNC laser welders, which gives the best possible process repeatability and tuneability.  The weld can be tuned to be as small as you require for the delicate job at hand.  We recently delivered a pulsed version for welding 0.004″ (0.1mm) inconel and stainless steel foils, which the customer was extremely happy with.

Very small weld 0.040" on stainless steel disk
Very small weld 0.040" on stainless steel disk

What is the maximum thickness for tube laser welding?

Stainless round parts with laser welding
Eighth inch stainless (3mm) laser welding

Our 3kW systems can laser weld up to quarter inch or 4 gauge stainless steel, aluminum and steel at high speed with full penetration in one pass.  

2kW machines are suitable for laser welding up to 4mm at high speed, or thicker by slowing down.

The image on the left shows 1/8″ (3mm) wall thicknes tube that was assembled wtih a spigot to control radial runout.  Control of runout or concentricity is important when setting up and helps ensure a good end result. 

Our customer ground this part back so it was flush and was very happy with the result.