Multitask machining heroes

END USER: Holmatro Inc., (410) 768-9662, holmatro-usa.com.
CHALLENGE: Produce parts faster without investing in additional fixturing.
SOLUTION: Efficiently reprogram the parts with the company’s CAM software after moving part production to a multitask lathe.
SOLUTION PROVIDER: DP Technology Corp., (800) 627-8479, www.dptechnology.com.

The hero isn’t always the guy in the cape. Symbols of the modern white knight notwithstanding, sometimes he doesn’t even wear a badge or ride on a fire engine.

In this case study, the guys in the “white hats” are with Holmatro Inc., a manufacturer of rescue equipment—including hydraulic spreaders, cutters and rams—used to extricate people pinned inside vehicles after traffic accidents.

“Getting rid of the metal when someone is trapped is the first thing rescuers do when they assess the accident scene,” said Chuck Cain, manufacturing engineer at Holmatro’s Glen Burnie, Md., facility. “Anything we can do to chop minutes off at the scene can make a real difference.”

He added that the company continually invests in R&D to find ways to make better products. “Innovation is fun for me, and it all comes down to having the right tools for the job,” Cain said.

One of those tools is CAM software. When shopping for a CAM package in the past to eliminate the programming of machine tools longhand at the control, Cain noted Holmatro examined the offerings from “everybody in the CAM business” before selecting ESPRIT CAM software from DP Technology Corp., Camarillo, Calif.

Cain explained that one of the reasons for choosing ESPRIT is it helps impart specified finishes of 0.3µm Ra to 1.6µm Ra by properly adjusting the speeds and feeds during machining based on cutting conditions. This is especially critical when producing parts with contoured surfaces. “ESPRIT keeps everything consistent,” he said.

Smooth bore surfaces are essential for hydraulic components. This is because the company’s pumps flow hydraulic fluid at 10,500 psi, and the high-pressure flow increases the effects of any imperfection by making it bigger, such as a line, on a bore for a hydraulic cylinder, Cain pointed out. “It gets real ugly quickly, because any surface imperfections create a path for hydraulic oil to flow between the cylinder wall and the O-ring,” he said. “At 10,500 psi, that path would cause the O-ring to fail.”

More recently, Cain noted the CAM software provided a solution when the vice president tasked him with boosting throughput for runs of 300 pump coupling adapters. Holmatro produced the part unattended on a horizontal machining center, but was only able to make 32 pieces a day. To increase production of the parts and utilize a full 24-hour day instead of just the cycle time from running one set of fixtures, Holmatro would have had to purchase five vices and five riser plates for a total cost of at least $36,000. “That job was truly a bottleneck,” Cain said.