Above: The dross left behind by the plasma torch is almost non-existent, and the plasma cutting moves much faster than waterjet, says CFO Russ Kirchner III.

Fifth-generation processing line holds tight tolerances on heavy-gauge metal while saving time and cash compared with other machinery

September 2022- Fits and starts. That is how things eventually move forward during a global pandemic and when the U.S. manufacturing sector experiences a massive shortage of skilled labor. That was the case for High Performance Alloys Inc., Tipton, Indiana, and its most recent equipment upgrade.

High Performance Alloys stocks and processes stainless steel, nickel and occasionally cobalt products in forms that include round bar up to 16 inches in diameter, sheet and plate, wire and tubing. The company offers custom cutting with shears, plasma cutting, band saws and waterjets.

     Over time, HP Alloys placed the right operator with the new plasma cutting machine, and is fine tuning tolerances.

CFO Russ Kirchner III says the company found that its existing plasma cutting machine wasn’t performing as well as customer demand required. Operators studied the old unit, a secondgeneration Hypertherm that was built in the early 1980s. “The PLC motherboard was no longer holding together and we had difficulty replacing parts. When we disassembled the old machine, it was not able to cut circles or rectangles,” he says.

The company decided to install a new plasma table because “we did not want to shop out parts to have someone else cut them. And we had to be able to pierce and cut material at least 3 inches thick.”

Praxair, now Linde, which supplies welding gas to HP Alloys, helped the company to procure a fifthgeneration Hypertherm high-definition plasma cutter and all the accessories needed.

Kirchner says there was a four-month wait to obtain the new unit, which arrived at the end of 2019. It has taken a couple years since then for the machine operators to become fully capable of utilizing the tolerances of this precision machine. Besides the difficulty of COVID-19, “we went through several different plasma operators. One wanted to go into sales,” for example, Kirchner says. “We finally got the right operator and we are still fine-tuning the tolerances. We used to have difficulty with tight corners but now we can adjust for those cuts. Now we are training our sales force to sell the plasma cutting capabilities.”

TOLERANCES

Using the high-def plasma machine, “we are able to pierce and cut over 3-inch-thick plate. With this unit, we can hold a tighter tolerance than we were previously,” Kirchner says.

Bob McLain, a plasma operator at HP Alloys, says that the tolerance of cuts depends on the thickness of the material. Under 3/8th inch thick, the plasma machine can hold to within 1/16th inch; and with leads and exits, it can hold even tighter tolerances. From 1/2 inch to 3/4 inch thick, 1/8th-inch tolerances can be expected.

“Above 3/4 inch, we still hold about 1/8 to 3/16 inch,” says McLain, who has been with the company for five years. “Even up to 11/2 inches, we can hold under 1/4 inch. At about 21/2 inches, because of the corners, the tolerances are less stringent. At 2 inches, we achieve less than 3/16 tolerances, half the distance of the old tolerance.”

By comparison, the old tolerances were between 1/4 to 3/8 inch on 3-inch-thick plate. “Certainly, we get a cleaner, smoother cut than we did with the old machine,” says McLain.

QUICKER CUT TIMES

Kirchner says that the dross left behind by the plasma torch “is much less, almost non-existent,” compared with the previous machine HP Alloys was using. With the dross that does remain, “it doesn’t take very long to remove it. Previously, it took time to grind the dross off.”

It is also a smaller heat-affected zone compared with previous machines. The zone is smaller in which the material has a heat signature. If they are welded at that point, there are no issues.”

With the new plasma unit, the tolerance “is barely a step down from a water jet but it is 20 times cheaper than a water jet,” Kirchner says. “It takes longer to operate the water jet. The plasma is so fast that operator time can be spent elsewhere. The gas consumption cost is less, and you are using more energy on the water jet for a longer period of time.”

APPLICATIONS

HP Alloys has created “some interesting parts with the plasma cutting machine,” according to Kirchner.

     Applications for plasma-cut sheet and plate include parts for public utilities, ships and aerospace.

Shannon Beaver, a plant manager who has been with the company four years, says, “We have done work for public utilities, manhole covers, marine and shipbuilding, some for aerospace. We can import drawings, and create shapes from those,” she adds. “Other projects include replacement parts.”

The company has tasked the plasma machine with such components as fire pit rings and knives that have a knuckle guard. “Those are the fun projects,” says Kirchner, but “we can take on any design plan.” The unit can also perform lettering and etching, such as for indicating where bolts or other components should be placed on the plate.

“We are also able to create bolt holes depending on the thickness of the material. We can pierce 3/8th of an inch in thin sheet, and 1/4-inch ID on 1/4-inch-thick stainless plate,” says Kirchner.

The plasma unit is somewhat underutilized at the moment, but High Performance Alloys is available to perform conversion work for other distributors and fabricators in the Midwest, while offering customers faster turnaround times and lower cost than other cutting methods. MM