Handling Die Castings In A Harsh Environment

Handling Die Castings In A Harsh Environment
(Posted 04/30/2004)

AMCAN (Hamilton, Ontario) was founded in 1936 and has grown to include four additional, ancillary companies, both in Canada and Latin America.  Today, the AMCAN group of companies is a highly regarded Tier 1 full service supplier of large scale, high pressure aluminum castings to the automotive industry.  This includes a complete design engineering staff, machining and QC departments in addition to the die castings themselves.  ‘‘AMCAN has a wide spectrum of capabilities for the production of oil pans, transmission cases, differential cases, four-wheel drive transfer cases and gear housings,’‘ stated Mike Kowaleski, AMCAN Plant Manager, ‘‘as well as being able to produce specially engineered, complex castings.’‘

‘‘The majority of the die casting operations are done internally at AMCAN,’‘ continued Kowaleski, ‘‘and with the variety of components manufactured, efficient parts handling is a major concern for us.’‘  One particular challenge is the heat treating of a chain case cover for a series of FORD vehicles that is manufactured in two similar part numbers with a slight variation to their overall size.  ‘‘We initially used fixture grippers mounted to swing cylinders.  The problem we were having with them, is that in dye capping, you’re always doing flow analysis so you’re changing overflows, changing gating and you’re constantly having to move everything around.  I figured there’s got to be a better way of doing this’‘, said Kowaleski, ‘‘ so lets go directly to the casting.’‘

The problem that AMCAN encountered in parts handling was the extreme temperature range of the operation.  The heat treat hits 1200° F to 1250° F and as the casting emerges from this operation the grippers send it to a room temperature quench bath.  Kowaleski started with installing commercially available grippers, but found continual seizing problems once they left heat treat and hit the quench.  ‘‘The basic design left something to be desired,’‘ continued Kowaleski, ‘‘and basically the cost of repair was more than the up time, so I knew we had to try and do something different.’‘

Kowaleski saw an advertisement for SCHUNK grippers and immediately contacted Brent McCurdy at Sempress (Mississauga, ON) who represents SCHUNK products in Ontario. 
McCurdy met with Kowaleski and reviewed the part.  The casting of a three cavity die weighing in at about 40 lbs.  ‘‘We recommended installing models PSH long stroke gripper and DPG three finger grippers,’‘ stated McCurdy.  ‘‘With the SCHUNK products being sealed, I was pretty sure we’d eliminate the seizing issue right off,’‘ he continued.  ‘‘We’ve worked with Mike on an ongoing basis and knew he is pretty good at calculating what he needs,’‘ continued McCurdy.

Kowaleski added, ‘‘I went with the two (different grippers) for balance and to accommodate the slight differences in part size.  There are two designs on that part, and each one of them is a little bit different.  The gripping location is off a little bit, so when we machined it there is a rotation of three that can be still held by the grippers.  The square piece where the two jaw is gripping is always in the same location.’‘  McCurdy continued.  ‘‘The parts are unusual shapes, they’re not symmetrical, they’re always off balance or they’re heavy on one side not on others.  The SCHUNK grippers help accommodate this discrepancy.’‘

AMCAN produces about 65-70 heat treated castings an hour.  ‘‘Being able to accommodate the two different part sizes without having to reset the grippers is great,’‘ concluded Kowaleski, ‘‘but with the spray, temperature variations and generally harsh conditions in here, the parts handling has been the least of our problems.  We’re able to concentrate on the other aspects of our operation without the headaches of the downtime we had experienced.’‘

AMCAN found the SCHUNK grippers to be incredibly reliable as well.  Installed in the early part of 2000, this operation is basically unattended and runs 24/7.  ‘‘AMCAN’s business has been built on providing high quality castings, coupled with responsive customer service,’‘ concluded Kowaleski.  ‘‘We have learned that even something as simple as a gripper can make a significant impact on our entire business.’‘