Welding units help minimize conversion costs for tube producer

Situation

The Troxel Co. has been producing high-frequency welded specialty tubing for more than 50 years. More than just surviving in challenging markets—including automotive—and difficult market conditions, it thrives under such circumstances, claiming to have the lowest conversion costs in the industry.

Troxel’s capabilities focus on productivity and quality, for example making tubular products at speeds up to 600 FPM yet maintaining sufficient quality control to comply with TS 16949-2009 and ISO 9001:2008. More than a tube producer, it has established itself as a fabricator also, providing tubular components and assemblies to a variety of OEMs.

The company recently undertook a search for a power supply that would help it improve productivity and continue to minimize conversion costs.

Resolution

The company invested in a current-fed inverter (CFI) type welding unit from Thermatool. A solid-state, high-frequency welding unit equipped with the company’s patented AutoMatch™ feature, it delivers 50 to 1,200 kW at a fixed frequency from 150 to 800 kHz.

Two key benefits for Troxel, given its diverse portfolio, concern the unit’s stability. First, CFI technology delivers full power output over a range of product sizes; second, its welding frequency is stable, unaffected by changes in weld area setup, tube OD and wall thickness, and impeder material.

In addition to its consistent output—the power varies less than 0.5 percent and the frequency varies less than 1 percent—it is equipped with a rectifier that prevents interference with other electronic components and systems on the mill, including inspection equipment.

Craig Bowen, technical service manager at Troxel, reported that upgrading to the latest welders from vacuum tube designs has been beneficial to the company.

“We get better uptime, and the CFIs are more energy-efficient,” Bowen said. After the unit is set up—which is easier than with previous units, Bowen noted—the company benefits from production improvements.

The control unit is dynamic, matching the weld power to the mill speed so that the mill produces less scrap when ramping up to full mill speed and ramping down at the end of a run. Troxel gets prime tube from nearly all of the strip that goes through the mill.

“Our welding process is all-around better with the CFI welders,” Bowen said.

And, while it uses several generations of power supply, keeping them up and running hasn’t posed any sort of a problem, according to Bowen.

vThermatool supports each model with spare parts and technical service for the life of the machine, so every Troxel welding unit is still up and running.

“All of our solid-state welders, regardless of the age, are fully supportable with spare parts, and even our welders older than 20 years are fully serviced—nothing is obsolete,” Bowen said.

“Thermatool’s technology has made our transition to solid-state equipment extremely smooth,” he added.

Thermatool Corp., thermatool.com