Turning Center Helps Medical Company Reduce Cycle Times

Keen competition in a growing market segment and maintaining necessary standards of quality make the medical implant industry a challenging business. EBI, L.P. (Parsippany, New Jersey), a subsidiary of Biomet, Inc. (Warsaw, Indiana), designs, develops, manufactures and markets products used primarily by orthopaedic medical specialists in both surgical and non-surgical therapy.

Incorporated in 1979, EBI received FDA approval that same year to market the world’s first non-invasive bone growth stimulator. Four years later, EBI expanded its product line when it gained distribution rights for an external fixation device that allows loading of a bone fracture to enhance healing. External fixation is used on patients when conventional casting to immobilize the bone during healing is not an option.

A fixator is an integral ingredient to successful bone healing. The fixator is placed over screws inserted into the bone so that the screws are held in place. There are fixators for virtually every part of the body, and more are being introduced every year.

EBI has partnered with Mori Seiki (Irving, Texas) for the past 11 years. EBI has 15 Mori Seiki mills and three Mori Seiki lathes.

The process leading to EBI’s latest purchase started when production manager Ray Mount traveled to Japan to tour the Mori Seiki facilities. One of the new machines he viewed was a DL-151Y, a twin spindle turning center with a Y axis. The machine was working on a part similar to one that would be run at EBI. Mr. Mount resolved to set up an appointment with Maruka (a Mori Seiki distributor in Rockaway, New Jersey) when he returned home.

Of course, there were test parts to be run to see if the DL-151Y really fit the bill. Bob Nakash, regional manager, CMTSE, of Mori Seiki’s New Jersey Technical Center, says, “They came to us with a fixator and asked us to propose a system that would make them more efficient. We then had our engineering meeting with them and proposed doing it on a DL-151Y and making this cycle time. At that point they said, ‘If you can make that cycle time, you get the order.’ We developed the cycle time. They gave us an order subject to making the part to the required tolerances.”

The EBI has seen results from the DL-151Y. “A lot of jobs that took three or four operations, such as one lathe and three milling, we can now do complete with the DL-151Y,” Mr. Mount says.

The resulting reduction in cycle time has been significant. The average reduction of cycle time per month in the latter part of 2001 shows 66 percent in September, 61 percent in October, 72 percent in November and 67 percent in December.

“If you analyze each job that we’ve put through that machine,” Mr. Mount says, “the minimum cycle time we’ve saved is 50 percent.”

Once EBI realized the turning center’s potential, the company reevaluated all of its jobs that had lathe and milling operations. Because of the efficiency of the machine, 7 queue days were knocked off operation. “This increased efficiency allowed us to reduce the time required to make the part,” Mr. Mount says.

The DL-151Y often runs 24 hours a day at EBI. The company runs two 10-hour shifts, so the machine runs 20 hours attended and 4 hours unattended. Only one person works on the machine, and Mr. Mount says that he only puts 2 hours of time into the job a day, and those hours are to inspect the part.

“We make one adjustment per day and that’s it—even with tight tolerances,” Mr. Mount says. “It runs continuously.”

The reduction in labor costs, combined with the reduction of cycle time and parts costs, has yielded big monthly savings for EBI. Within 12 months of purchasing the DL-151Y, the company had recovered all costs of the purchase.

EBI has not experienced problems with accuracy, either. “Normally, if a machine doesn’t run through the night and is started up cold in the morning, it will have moved 4/10ths or 5/10ths because of thermal expansion of the components,” Mr. Mount says. “The Mori Seiki, though, doesn’t move overnight.” Mr. Mount says that the first piece of the morning is exactly like the last piece of the evening before.

That’s not surprising to Mori Seiki’s Mr. Nakash. “A Mori Seiki machine is built so that the effect of thermal expansion is hardly known,” he says. “If everything grows in the machine cooperatively, then the machine doesn’t change size.”

Another feature of the DL-151Y is the machine’s identical opposing spindles. Users can complete two operations in one setup or work on two different jobs at the same time. “There is the same power on the left and the right,” Mr. Nakash says. “It has the same capability on both sides and has ability to do dual processing, which means that whatever it’s doing on the left side, it can be doing something entirely different on the right side.

“In EBI’s case, there was an equal amount of work on both sides of the part. So if we took what would be a 10-minute cycle and put it on the DL-151Y, it would be virtually a 5-minute cycle because of the machine’s capability.”

Six months after taking delivery on the DL-151Y, EBI was ready to take delivery on a second machine.