May 13, 2008
Powder River, a Provo, Utah-based fabricator of farm implements, turned to KNUTH Machine Tools USA for a three-roll bender the company uses to make its round bale feeders for horses.
Hugo Hernandez and his shop floor team weren't horsing around on the shop floor, but it sure did take them more time than it should have to bend 14-gauge sheet for a horse feeder.
The round bale feeders are one of the more popular products fabricated by Powder River, Provo, Utah. Unfortunately, keeping up with orders was growing more difficult.
The goal was to bend the sheet, with 14-ga. tubing stays welded to it, to create a half-moon shape that would create an 8-foot-diameter circle when joined to a similar fabrication. That circle acts as the bottom pan that has 16-ga. tubing dividers attached; the vertical dividers help to keep the horses separated as they feed and reduce hair loss caused by rubbing.
Hernandez and his team, however, were working with an older hydraulic roll bender that couldn't hold tolerances from one job to another. When the team would send a sheet through the bender, it had no guarantee the same tolerances would be held, despite everything remaining the same from the previous job. Plenty of scrap resulted.
"It was giving us a hard time because we used it quite a bit," said Hernandez, Powder River's maintenance supervisor, but formerly the company's production manager. "We were spinning our wheels with that one."
Finally, in 2006, Hernandez received the green light to pursue a replacement for the old roll bender. The search for a new piece of equipment was much more streamlined when compared with the time-consuming job of working with the old bender.
Before embarking on a large-scale search for roll bending equipment manufacturers, Hernandez talked with co-workers. A sister facility in North Dakota had purchased a press brake from Knuth Machine Tools USA Inc. and liked the product. Hernandez discovered the company also made roll benders and decided to give them a call.
Upon looking at the company's equipment, Hernandez elected to go with the KRB 2508 three-roll bending machine, which has three hydraulic motors and a rotary reduction gear. A control panel gives the operator the power to adjust side and bottom bearings, as well as the feed rate and parallelism of the rolls. The roll bender was designed to handle a work length of 102 inches and a maximum thickness of 0.55 in.
The spec sheet looked great, but what really sold Hernandez on the equipment was the 2-in. gap that could be opened between the bottom roll and the top roll.
"The reason that we bought this bender is that it can open quite a bit for the tube to go through," he said.
A good reference and a big gap proved to be a winning combination for Powder River. The shop floor produces less scrap, and the operators don't spend as much time pulling and pushing the sheet metal in hopes that it will square up and meet the required tolerances.
"That was a big problem for us. We experienced a lot of overtime to complete jobs," Hernandez said. "Now that's been cut down to a quarter of the time it used to take to complete the job."
Powder River is not a novice when it comes to metal bending. Hernandez estimated the shop floor was pushing about 300 jobs per week through the old roll bender, working on the equipment for a couple of hours each day.
Rolf Seyferth, regional sales manager, Knuth, noticed that when he saw pictures of the equipment installation at Powder River. He saw that the Powder River guys fabricated a big die that went across the top of the machine to assist the sheet metal in clearing the gap and squaring up properly so it can be rolled evenly.
"With the big die on there, they obviously know what they are doing," Seyferth said.
Hernandez acknowledged the equipment "keeps it pretty squared." That's one of the benefits of a three-roll, initial-pinch machine. Once the sheet is pinched by the first rollers, it remains square throughout the entire rolling process, including prebends of the front and trailing ends of the plate.
That was about the only change that Powder River made to the three-roll bender. The company added some new safety mats around the equipment and still rely on the same crane to handle the sheet.
"It's easy to pick up on, and I have several people trained to use it," Hernandez added.
If he or his team yearn for the not-so-good ol' days, they can still visit the old roll bender. It was sent to live out its golden years in a sunnier climate at a sister facility in Oklahoma City.
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