LEBANON — Harry Mellott donned a welding helmet, dropped the face shield and fired his plasma torch at a square of steel, cutting through it like a hot knife slicing through butter.

His demonstration of the new Powermax SYNCH air plasma system was part of a tour Wednesday at the Hypertherm plant in Lebanon. The tool is a finalist in the New Hampshire Tech Alliance’s 15th Annual Product of the Year competition Thursday.

Mellott held in his gloved hand what looked like a black, rubberized pistol-grip nozzle for a garden hose, but instead of water it was spraying a plasma stream four times hotter than the surface of the sun.

The tool creates plasma when an electric current from a power supply ionizes gas forced through a narrow opening.

Hypertherm got its start in 1968 at a time when oxy acetylene torches were the most common way of cutting metal. Over the intervening years, the plasma cutter market has grown exponentially.

“We now see a lot less oxy fuel systems being used for fabrication jobs around the world,” said Mellott, a senior project manager in marketing.

“It still has its place. There are things oxy fuel can do that plasma doesn’t do very well, like heating metal, to bend it, to remove rusty bolts, things like that, but there are a lot of disadvantages to oxy fuel as well. It is very slow. It doesn’t have good cut quality. The heat can cause the metal to deform, and you can get warpage.”

Hypertherm’s Powermax SYNCH series has a number of advances over previous models, including single-piece color-coded cartridges that are easy to change on a job site without having to reinstall multiple parts.

There is a radio frequency identification system on the tool that makes it simpler to operate and lets the user know how it is performing. A detector advises when the cartridge needs to be changed.

Controls on the torch handle allow for adjustments without the user having to return to the power supply box.

The advances cut down on the training necessary before a worker can use the torch on a job. They also improve convenience and efficiency in the field for workers who might be on scaffolding or otherwise separated from the power supply.

“Training is an issue for many manufacturers today with lack of skilled labor being a problem,” said Rafael Barrera, marketing team leader. “Now you can train an operator in minutes.”

The devices are built in a high-tech facility that employs hundreds of skilled workers. Numerous computer-controlled robotic arms whip to and fro as part of the manufacturing process. On-site laboratories test the products to ensure reliability, including shake and vibration tests.

“Our products are designed to operate in a variety of environments, high temperature, low temperature, high humidity, low humidity, sea salt, you name it,” Mellott said. “Our systems are designed to last even in some of the harshest environments.”

In addition to its portable cutting tools, the employee-owned company also makes large cutting machines designed for use 24 hours a day and seven days a week in industrial settings.

Hypertherm, which has annual sales of more than $500 million, employs 1,840 people, including 1,200 in New Hampshire. The company is looking to recruit machinists, assemblers and engineers. It trains machinists in a three-month accredited course, and a position at the company is guaranteed for those who pass.

“We’ve never had a layoff,” Mellott said. “Even in 2008 and 2009 when things were really slow, we put everybody to work. It was an opportunity for us to rethink how we manufacture. It was an opportunity to do a lot of maintenance. We had people doing painting. People were cleaning, reorganizing, thinking about our manufacturing flow.

“So when business started to pick back up again, guess what, we had everybody on board, everybody was trained. As orders came in we were able to provide our product that much quicker than our competition, who had massive layoffs.”

The employee-owned nature of the business gives staff a stake in its success.

“Our stock is all private,” Mellott said. “One of the benefits of being a Hypertherm associate is stock ownership. You have profit sharing at the end of the year. It really is a unique culture.”