Automated Plasma Cutting

The automated plasma cutting industry has been clouded by low-cost
integrators and manufactures. There are continuous advances in technology
which causes plasma cutting systems to constantly improve.

Plasma cutting was the result of putting an electrical arc through the
gas that’s blown, at high pressure, through a nozzle. This causes the
gas to turn into a plasma substance and produces a flame that can reach
50,000 Fahrenheit. An automated plasma cutting system is classified as
a precision (high-definition) or conventional, based on characteristics
of the cutting flame. A precision of automated plasma cutting is capable of
achieving faster cutting rates, producing tighter tolerances, and producing
less bevel and kerf than a conventional plasma system. The cost of these
units, however, is significantly higher than the conventional plasma
system. This is why it’s important to match, properly, the automated plasma cutting
system with the shape cutting machine.

The most common and expensive pitfalls a buyer can encounter is when a
manufacturer mismatches a machine and power sources. This is the result
of a manufacturer not taking time to understand a buyer’s
requirements, having limited OEM access to power source, limited or single-product
line of machines, or lack of industry knowledge. These companies will
sell with focus of low price, highlighting the high points of the
automated plasma cutting system instead of looking at its limitations.

The most common machine is gantry or bridge style machines made from
extruded aluminum or fabricated steel. Machines that are constructed
using extruded aluminum are usually considered to by a hobbyist’s machine
and usually are appropriate when doing a small amount of cutting.
Fabricated machines, made of steel, are highly recommended for any continuous
cutting process. Auxiliary heat shields can be made available to
protect the automated plasma cutting system and it’s components from heat damage.

Cutting machines have a variety of drive systems such as single-motor
dual-side drive, single-side drive, and two-motor dual-side drive
systems. A well made single-side drive system or a single-motor dual-side
drive system will perform well in conventional plasma application. The
benefits of a two-motor dual-side drive system won’t be noticed in
conventional plasma applications due to its limitations. A two-motor dual-side
drive system would provide accuracy and performance that would be
required to achieve optimal results from any precision plasma process.

Sizing gear boxes to motors relative to the mass of a machine is also
important. And undersized motor will be unable to change the direction
of the mass effectively, at high transverse and cut speeds. This would
result in un-uniform cutting quality and washed out corners.

The unit that ties all the functionality of the plasma source and
machine is the CNC control. The two classes of controls used in automated plasma cutting today are produced by Hypertherm or Burny. They have user friendly touch
screens and can be housed to stand up in harsh environments. There are
industrial controls, which are highly recommended for applications, and
are designed for specific requirements, and are prone to less PC
problems.

One other important feature, that is often overlooked, is the
construction of a railing system. Automated plasma cutting can produce in harsh
environments, making a railing system important. The components used in a
railing system should be big, so they can exist in this type of environment.
Automated plasma cutting should be constructed with hard material, and cleaned regularly, to stay clean of molten steel that will fall on them. Also recommended
are self-cleaning wheels that keep the wheels clean when doing
preventive maintenance. The size of the rails should also be bulky enough to
prevent any deflection as a machine travels across them.