Time to upgrade equipment: Turning Performance

Recently, a search for two new vertical machining centers resulted in my shop acquiring a lower-cost alternative horizontal.

Before the purchase, our machines had an average age of 18 years and were all from the same builder. They included horizontal machining centers with 400mm and 500mm pallets, turning centers and low-horsepower, general-purpose VMCs.

One of our oldest HMCs had seen its better days, even though it still held size. It had an eight-pallet pool, meaning eight pallets could shuttle in and out of the HMC to enable continuous production. Unfortunately, the pallet pool was never utilized to its full capabilities and became more of a fixture storage center than a productivity booster.

One day, the directive came from upper management to increase throughput—period. Based on our calculations, we could have two rotary-pallet VMCs run by one operator and replace the old horizontal. This would reduce cycle times by 50 percent to less than 5 minutes per part. Two verticals would have a faster throughput simply by the virtue that one machine would be running operation No. 1 while the other would be running operation No. 2. As a bonus, they would have a smaller combined footprint than the HMC, which is also what management wanted. My task was to find the right VMCs.

I was relatively new on the job and didn’t know anyone, so I contacted 14 dealers covering the gamut of machines I thought could handle our parts production. A couple of dealers that represented European builders were immediately ruled out—not because of the product, but because of the high cost vs. our production requirements. If we were running thousands of parts per week, the high-end European machines definitely would be my taste. But, I don’t want to take anything away from the Pacific Rim manufacturers, which also offer some fine products.