Above: Illustrations of a spring-loaded regulator (left) and a dome-loaded regulator (right).

Optimize laser cutting to avoid profit droop

February 2022 - A modern laser-cutting machine is not cheap. But many fabrication shops invest in them because they are well worth the price. With the ability to precisely cut everything from mild to stainless steel, titanium and more, the hefty investment is offset by a laser’s unmatched performance and reduced waste in the manufacturing process.

However, many fabrication shops are only using general-purpose, spring-loaded regulators to supply gas for this high-performance cutting, which is like putting snow tires on a sports car. They simply are not up to the task of providing the consistent, reliable gas pressure needed to provide optimal performance. Servo dome-loaded regulators are a better option.

Consistent pressure

A dome-loaded regulator consists of two different regulators: a pilot regulator and a diaphragm-actuated dome regulator, which run parallel in the gas stream. The pilot regulator, which is spring-loaded, uses a small amount of gas to pneumatically actuate the diaphragm that acts on the gas valve in the dome regulator.

On the other hand, a general-use spring-loaded regulator allows for fluctuations in delivery pressure when the inlet pressure changes. When the delivery pressure changes as the flow increases, that is known as “droop.” For such a precise machine like a laser cutter, droop can really hurt performance.

Consistent inlet pressure is one important reason why dome-loaded regulators are the better choice for laser cutting machines. However, dome-loaded regulators also provide consistent, constant outlet pressure as demand from the laser fluctuates, which leads to better, more dependable outcomes. This regulator technology monitors the outlet pressure so that, when the demand from the laser increases or decreases, the valve opens or closes accordingly so that the outlet pressure remains constant, another safeguard against droop.

It is critical that laser cutting machines have consistent, stable pressure, not only during jobs but also in between jobs. When the pressure drops, these machines will shut down, creating downtime. And when fabrication shops are cutting 400 to 500 inches per minute, even a short downtime can hurt both productivity and profitability.

Even more possibilities

Stable delivery pressure is just one advantage for dome-loaded regulators. They also allow for faster piercing times. Additionally, the design of a dome-loaded regulator makes it more durable than a spring-loaded regulator.

Finally, while many laser cutters run on dome-loaded regulators that handle between 0 and 500 psi, some of the more modern machines may require a higher pressure. With that in mind, Harris offers a dome-loaded regulator with the standard 0-500 psi range, as well as a model with a 0-1,000 psi range. When investing in a dome-loaded regulator, make sure to check the machine’s requirements in order to maximize performance. Finding a regulator that can ensure the purity of gas by eliminating contaminants as well as provide optimal pressure can maximize profitability while minimizing downtime.

Accessories can make a difference

Fab shops often underrate the importance of the use of proper hoses. However, if they want to get the job done right, they need hoses that are specially cleaned for high-purity laser gases while also providing the correct inner diameter for laser applications. This eliminates possible contaminants and also ensures a consistent flow rate.

Additionally, there are many fabrication shops that not only run nitrogen for precision materials but also oxygen for mild steel. For these shops, a laser gas assist kit is the easy way to run both gases to a laser machine. It has everything the shop will need, including two dome-loaded regulators for each of the assist gases (oxygen and nitrogen), along with two ID laser assist gas hoses. There is also a premium kit option that includes particulate filters that protect laser optics. However, both kits include CGA fittings that hook up to a 12-pack, cylinder or bulk system.

The bottom line

Every shop should have dependable performance from its laser cutting machines. From manufacturers to distributors and down to the customers, performance is what it’s all about. Getting the most out of your laser cutting machine is a win-win for everyone.  FFJ

David Gailey is the product manager for specialty gas equipment at The Harris Products Group, A Lincoln Electric Company, and has over 35 years’ experience in the industry. He is currently Chairman of the CGA Industrial Gas Apparatus Committee and also serves on the Standards and Technical Panel for Underwriters Laboratories.