Bulldozing big workpieces: Drilling Performance

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END USER: MSI Corp., (724) 567-6500, www.msicorporation.com. CHALLENGE: Effectively cut a large amount of material on older machines without damaging cutting tools. SOLUTION: A milling cutter tooled with inserts that enable a large DOC at a low horsepower. SOLUTION PROVIDER: Sandvik Coromant Co., (800) SANDVIK, www.sandvik.coromant.com/us

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When removing 0.75 ” of material from a 50-ton forged steel workpiece in a single pass, you need a setup that can take serious abuse. Finding the right combination of satisfactory surface finish and profitable production was a challenge for MSI Corp. But a test of a new milling cutter led the company to a simpler and faster machining process when milling heat-treated 4340 alloy steel. When applied throughout the shop, the new cutter allowed MSI to increase productivity by 75 percent through taking on more work. In the process, the cutter got a nickname—”The Bulldozer.”

Vandergrift, Pa.-based MSI is a large, diversified steel and titanium processor. It performs first-stage machining (gauge reduction) and material conditioning (defect removal) on large workpieces for metal producers.

MSI also performs abrasive blasting, abrasive sawing, belt grinding, bar peeling, bandsaw plate and dial column sawing, centerless grinding, CNC turning, deep-hole drilling, heat treating, planer milling, vertical boring and waterjet cutting.

“We are in the middle of the entire process,” said Duke McLaughlin, CEO of MSI. “It’s not uncommon for the material to come to us multiple times for the same process between different production phases.”

Workpiece size and weight—up to 70 ‘ long and from 8,000 to 125,000 lbs.—make setup difficult. Add the task of cutting difficult-to-machine materials such as titanium, stainless steel, carbon steel and P/M and you have a machining challenge few companies can meet.

With a specialized solution, MSI is up to the task. The company uses older—50 years old in some cases—manual planers built with 100- to 150-hp motors and twin columns capable of managing unwieldy workpieces.

The large planers are effective but can abuse cutting tools. Because of their massive size and power, the mills typically create a great deal of heat when machining. And, with only a few speeds and feeds available on the planers, MSI often facemills at less than ideal conditions.

“We’ve always had difficulty with the forged material we receive from our customers,” McLaughlin said. “The material is forged or rolled oversized in case there are cambers, twists and other manufacturing defects, and we have to remove a huge amount of material—fast!” The hammer-forged parts have divots and gullies from being hammered during the forging process. Extra material containing the defects is left on during forging and MSI removes it to achieve a smooth, workable surface.