Machine Technology: Preparation automation pays

Are your spindles cutting most of the time? Or are they often idle because you’re getting ready to cut?

If you answered yes to the latter, consider the lift that an automated pallet-handling system could provide. These systems allow pallets to be set up and moved into position while workpieces on other pallets are being machined.

“By disconnecting workpiece setup and part loading from the actual machining, these systems allow our customers to see up to 95 percent spindle utilization on their machines,” said David Ward, product marketing manager for Mason, Ohio-based Makino Inc.

Makino’s MMC2 automated material-handling system links Makino horizontal machining centers, pallet loaders and operators. A servo-controlled vehicle transports pallets via a rail line. Pallets ready for machining are delivered to a machine, if one is available. If not, the pallets are placed in a storage area.

A Makino MMC2 pallet system incorporates a rail-guided vehicle that links five of the company’s a81nx HMCs to work-set stations and pallet-stocker stands. Image courtesy of Makino.

The MMC2 can be expanded incrementally to incorporate additional Makino HMCs (systems installed in North America include up to 10 machines), as well as more pallet-storage and work-set stations.

The cost of a customizable MMC2 can vary greatly. However, potential buyers can probably expect to pay about 75 percent of the amount they paid for the machine tool itself, according to Ward.

Einberger added that an MMC2 can almost double a machine’s production capacity. The MMC2 can feed multiple machines operating simultaneously. In addition, each machine can be set up to manage its own job independently of the others.

Running the show in an MMC2 cell is the PC-based Makino Advanced System-A5 (MAS-A5) control, which handles a variety of tasks. For one, the MAS-A5 monitors and manages the cutting tools in every machine in a cell. If a tool breaks while a machine is running a No. 1 priority job untended, the control instructs the machine to switch to a backup tool. If none is available, however, the control will check to see if the required tools are available to run the No. 2 priority job. And, if necessary, “it will cycle through all its jobs until it finds something it can run to keep that spindle turning,” Ward said.

Recently, Makino added a kitting function to the cell control’s capabilities. Common among aerospace suppliers, kitting is a practice in which separate but related items are grouped, packaged and supplied together as one unit for parent elements, such as a wing or fuselage. With the kitting function, Ward said, users can define a set of parts and tell the system how many sets are needed, when they are needed and when the work should start.

The MMC2 has traditionally been used with the company’s 4-axis HMCs. But Makino recently introduced an MMC variant that works with one of its 5-axis machines.

A new entrant in the pallet-handling field is the HS Flex from Hermle Machine Co. LLC, Franklin, Wis. The HS Flex is so named because it’s a flexible automation system capable of handling different-size pallets, explained Gunther Schnitzer, vice president of sales and engineering.