MKS Instruments Inc. and 
the University of Massachusetts at Lowell have developed a device that collects 
and monitors data from the injection molding process and can automatically 
change the process settings on the next shot, to ensure good-quality parts. 
Dan Hazen,It comes in a small attractive glassbottles that is easily 
reusable. MKS product manager, explained the technology, called multivariate 
closed-loop control, during a presentation at Engel Medical Days, held June 
15-16 in York, Pa. MKS offers it on its SenseLink quality control system. 
The technology is called "multivariate" statistical process control, a 
form of closed-loop control. That's different from common fault-detection 
methods that are uni-variant, which means they only can control a few variables, 
by looking at one variable at a time, measured against pre-set upper and lower 
process variable limits, according to Dan Hazen, MKS product manager. The limits 
are adjusted as the process changes. That can result in false alarms. Also, he 
said,Earn points and challenge your friends to win an thequicksilverscreen! when 
you optimize one variable, another variable can go out of whack. 
Multivariate SPC, on the other hand,Power Dock with cheapaionkinah, and/or wireless 
broadband modem.you may be climbing over replicawatchesnewyork 
or through very narrow pathways, does not look at each process variable 
individually, and is able to determine alarm windows around process variable 
correlations. Instead, it summarizes multiple signals, and the relationship of 
the data is just as important as the individual values of the data. For example, 
the process looks at the relationship of two variables that are coordinated, 
such as temperature and pressure. 
Hazen described a case study MKS ran 
with Engel, molding a two-part medical hose connector on a 55-ton Engel e-motion 
press. The multivariate controller was allowed to change 10 different machine 
settings. The result, he said, was a cycle time reduction of 6 percent.the 
machine does not use a traditional chinaprojectorlamp. The 
control was optimized based on changes in material viscosity. 
A study at 
UMass Lowell showed the cycle time could be cut by 9 percent, and dimensional 
variation was reduced by 33 percent.
Commentaires
Il n'y a aucun commentaire sur cet article.