American Kuhne has applied Single-Minute Exchange of Die (SMED) concepts to key tasks involved in extrusion job changeovers. The resulting three options are designed to substantially reduce downtime in tubing, profile, wire and cable, and other small-die production lines.
Rotary hopper after having been pivoted to
Available separately or as a package, SMED Quick-Change options cut changeover time by nearly half-an-hour when used in combination, according to the company. The options are available with the company's new extruders or can be retrofitted onto equipment from American Kuhne or other suppliers.
Three new features are incorporated in these options:
- Quick Collet Screw Pusher. This device reduces setup time for screw pulling from five minutes to less than one minute by use of a spring-mounted locking nut and a sliding collet to fasten the nut onto the threaded screw-pushing rod at the rear of the drive shaft. Conventionally, the rod is affixed by spinning a nut into position and installing and tightening six screws. Time saved: 4 minutes.
- Rotary Hopper: This reduces cleanout time to about one minute through its capability of being pivoted away from the feed throat for rapid dumping of excess material for vacuuming residual material and adding purge or new material. In contrast, cleanout of a conventional hopper requires about six minutes because it must be manually emptied of excess material and can be accessed for vacuuming only through its opening from above. Time saved: 5 minutes.
Dual-Head Arrangement: This system reduces the time needed to change dies from twenty minutes to only two by having a pre-heated head with breaker plate ready for fast replacement of the one that has been in use. Both heads are mounted on pivoting support structures on either side of the die area and have separate electrical connections. To replace a head, the operator simply loosens the clamping nut, opens the clamp, pivots away the previously used head, removes the breaker plate, mounts the preheated head and breaker plate, and closes and tightens the clamp. In a conventional system, one must remove the die nut, die, and tip before removing the head and breaker plate, insert a cold breaker plate, install the new head, insert a cold tip, die, and die nut, and wait for the system to reach working temperature. Time saved: 18 minutes.
"The SMED Quick-Change options are each an example of 'customextrudication' - a custom solution designed to help a particular customer, in this case those looking to shorten changeover times," said Bill Kramer, CTO of extrusion systems. "Because these are market-driven innovations that have solved problems effectively, we are now offering them as options for all our customers."