Cutting Quality of Laser Pipe Cutting Machine: Analysis of Influencing Factors

There are many factors that affect the cutting quality of the laser pipe cutting machine.

This article, based on theoretical learning and combined with my own experience, analyzes the inherent characteristics of the pipe cutting system, the laser pipe cutting process and the characteristics of the pipe to be cut.

The factors affecting the selection of the chuck of the pipe cutting machine, the cutting system, the supporting parts, the auxiliary gas, the pipe materia, the thickness of the pipe to be cut are analyzed to improve the pipe cutting quality.

Related reading: Tube Laser Cutting Machine: The Ultimate Guide

As shown in Fig. 1, the laser pipe cutting machine works in a similar way to the plane laser cutting machine.

It focuses the high-density and high-power laser beam on the surface of the pipe to be cut, raises the temperature of the laser spot area to the melting point or boiling point of the pipe to be cut in a very short time, so that the surface of the pipe to be cut can quickly melt or vaporize, thus completing the pipe cutting work.

When the laser spot moves along the set cutting route, it constantly interacts with the pipe to be cut to form a slit.

During the cutting process, various auxiliary gases are also required for slag blowing, cooling and cutting aid.

Related reading: The Application of Air as Auxiliary Gas in Laser Cutting

Cutting Quality of Laser Pipe Cutting Machine: Analysis of Influencing Factors 1

Fig. 1 Laser pipe cutting machine

Influence of inherent characteristics of pipe cutting system on laser cutting quality

Influence of Chuck Selection on Cutting Quality

A good laser pipe cutting machine must have a high-quality chuck assembly.

Excellent chuck assembly has a decisive impact on the pipe cutting machine’s feeding, processing, blanking and other processes.

There are many chuck manufacturers on the market now, each with its own characteristics, and a set of excellent chuck assembly must have the ability to ensure the repeated clamping accuracy, only in this way can the pipe precision of each clamping be kept within the controllable range.

At present, most manufacturers of laser pipe cutting machine will choose products with two or more chucks, including two chucks, three chucks and four chucks, which are the mainstream selection trend in the laser pipe cutting machine market.

Influence of Cutting System Selection on Cutting Quality

The pipe cutting machine manufacturer has selected a chuck combination suitable for its own products, which is equivalent to having perfect hardware.

To make the hardware fully play its role, it needs appropriate software assistance, such as an excellent pipe cutting system.

The popular pipe cutting systems in the market are those developed by enterprises such as FScut, Siemens and Beckhoff.

Because the laser pipe cutting machine is slightly different from the plane laser cutting machine, in addition to the conventional X, Y and Z axes, two chuck synchronous rotation axes are added, and some laser pipe cutting machine cutting systems will also add additional auxiliary axes, so as to ensure that in the whole process of pipe cutting. 

Related reading: The Ultimate Guide to Fiber Laser Cutting Machine

The chuck assembly clamps the pipe, and the auxiliary shaft can keep the pipe constantly following during the cutting rotation, so as to ensure that the pipe to be cut will not sag during the whole cutting process, and improve the cutting quality of the pipe.

Influence of tube cutting parameters on laser cutting quality

Influence of the Selection of Supporting Parts on Cutting Quality

At present, the basic length of pipes on the market is 6000 mm or more, which makes it easy for pipes to sag and swing in the process of clamping and cutting, greatly affecting the cutting accuracy.

In order to solve this problem, the laser pipe cutting machine manufacturer has developed a three chuck laser pipe cutting machine, and some even continue to explore the four chuck laser pipe cutting machine.

Related reading: Top 20 Laser Cutting Machine Manufacturers

Although the three chuck laser pipe cutting machine and the four chuck laser pipe cutting machine have good prospects in terms of tail length, cutting accuracy, and automatic feeding and unloading, the three chuck and four chuck laser pipe cutting machines have been selected.

Compared with the traditional two chuck laser pipe cutting machine, one or more chucks and more motor reduction gearbox combinations are added.

At the same time, more high-end and complex laser pipe cutting machine cutting systems are required for operation, which indicates an increase in manufacturing costs.

Therefore, when most manufacturers of laser pipe cutting machine optimize the phenomenon of sagging and rotating swing of pipes in the process of clamping and cutting, and at the same time consider the economy of the whole product, they finally choose the scheme of two chuck laser pipe cutting machine.

The material supporting parts are added between the front and rear chucks, just like the workbench of the laser cutting machine, which can follow and lift the pipe to be cut during the whole process of clamping and cutting, so that it will not sag and swing during the whole cutting process, which greatly improves the cutting accuracy of the pipe.

And at the same time, it has more possibilities to properly match the automatic feeding and unloading with the semi-automatic feeding.

In order to improve the cutting and blanking accuracy of long pipes, generally, a supporting part is also added in front of the chuck near the cutting head, so that when long pipes are blanking, they will be lifted continuously at the front end that has been cut, so as to ensure that the entire long pipe will not sag during the cutting and blanking process, so as to improve the cutting and blanking accuracy of long pipes.

Influence of auxiliary gas selection on cutting quality

When the laser cutting machine is working, it will irradiate the light spot formed after the laser beam is focused by the lens on the surface of the material to be cut, so that its temperature will rise in a very short time, thus reaching the melting point or boiling point of the material to be cut.

In the cutting process, the surface of the material to be cut can reflect the laser to a certain extent, and auxiliary gas can be injected during cutting to improve the absorption of the laser on the surface of the material to be cut and improve the cutting efficiency.

Oxygen, nitrogen, compressed air and other inert gases are generally used as auxiliary gases.

Related reading: How to Select Auxiliary Gas for Laser Cutting?

Oxygen is used as an auxiliary gas because it can promote the oxidation reaction on the surface of the pipe to be cut, thus improving the cutting efficiency.

When the laser cutting power and cutting speed are fixed, the larger the oxygen pressure is, the larger the kerf is, and the larger the stripes of the cutting section will be;

Related reading:

When the oxygen pressure is reduced, the cutting seam becomes thinner, and the stripes on the cutting section are thin and smooth.

However, when the pressure is reduced to a certain value, there will be significant cutting effect on one side of the pipe, but at the same time there will be slag hanging.

The falling of the slag hanging on the opposite side will affect the entire cutting accuracy, and sometimes it will be difficult to cut off the pipe being cut.

When cutting high thickness pipes, special-shaped pipes or pipes made of special materials, nitrogen and other inert gases are required as auxiliary gases.

Combined with the metal and physical characteristics of the pipe to be cut, compressed air can be selected as the auxiliary gas to control the cost without affecting the overall cutting efficiency.

Influence of physical and chemical properties of the pipe to be cut on the quality of laser cutting

Generally speaking, different cut pipes have different physical and chemical properties.

In terms of physical properties, such as the hardness, melting point and boiling point of the pipe to be cut, and whether it is easy to melt, the ability of the pipe to be cut is different.

While in terms of chemical properties, such as the flammability, stability, oxidation, combustion support and other aspects of the pipe to be cut are also very different, which makes different pipe to be cut have different requirements for chuck size, auxiliary gas type and pressure, and laser cutting power.

Under normal circumstances, the greater the thickness of the pipe to be cut, the higher the laser cutting power is required.

When cutting pipes made of special materials, such as aluminum pipes, copper pipes, stainless steel pipes, and even pipes made of materials with excellent oxidation resistance, as well as pipes with special shapes, such as special-shaped pipes, H beam steel, channel steel, and angle steel, there are different requirements on the power of laser cutting, the selection of auxiliary gas types, and the performance of the chuck itself.

In addition to laser power and auxiliary gas, the selection of supporting parts should be considered to ensure the overall cutting accuracy when cutting and processing the lengthened heavy pipe fittings.

Wrap it up

Through the analysis of the above factors affecting the quality of laser cutting pipe, the processing quality of laser cutting pipe can be guaranteed as much as possible.

It also enables the manufacturer of laser pipe cutting machine to produce advanced laser pipe cutting machine that can meet the processing requirements of customers based on the actual needs of customers, taking into account the market situation.

For the majority of laser pipe cutting machine users, selecting a high cost performance laser pipe cutting machine with the best laser pipe cutting system and laser pipe cutting process parameters can well ensure that the pipe products produced have high processing accuracy.

Leave a Comment

Your email address will not be published. Required fields are marked *