The Next Steps in Metalcasting Development Through Emerging Technology, Ideas
A sampling of presentations from CastExpo in Minneapolis focused on new ways to move the industry forward. A MODERN CASTING STAFF REPORT
O
ne of the biggest draws of CastExpo are the
presentations of completed research projects. Tey are shared and discussed and hopefully help metalcasters across North America improve their op- erations and help them better service customers. Tree of the presentations at Cast-
Expo are summarized below. Tese papers from industry experts represent studies and ideas that could have wide-ranging impacts.
PRESENTATION Predicting Casting Dimensions
With Computer Process Modeling AUTHORS Jerry Tiel and Sairam Ravi,
University of Northern Iowa, Cedar Falls, Iowa
BACKGROUND As liquid metal solidifies, it
contracts first in volume and then in physical size. Accurately predict- ing the final casting dimensions has been at best accomplished with a set of simple rules along with significant tribal knowledge. Although the age of creating master patterns with wood are mostly behind us, the industry still uses a fair degree of trial and error when produc- ing patterns to meet specific casting dimensions. Tis method was aided
by the use of “shrink rules,” and more recently, CAD geometry volume com- pensation, neither of which accurately predict final casting dimensions. Tis trial and error method of
producing patterns is very costly, often requiring as much as 40% of the original pattern cost for dimensional adjustments. Previous researchers have imperially studied the effect of various geometry and areas constrained by cores. Previous research by the Univer- sity of Northern Iowa in sand expan- sion has identified several mechanisms
whereby changes in the mold and core dimensions render current single volume percentage decreases inac- curate in determining final casting dimensions. By understanding the dimensional changes that the sand undergoes during rapid heating and the rigidity of the molding media, accurate predictions can be made to the final casting dimensions given a specific pattern size. Current research by the Univer-
sity of Northern Iowa has detailed a methodology using computer process
Metal is tapped into a ladle, which was part of the trials at the University of Northern Iowa. May 2016 MODERN CASTING | 53
Page 1 |
Page 2 |
Page 3 |
Page 4 |
Page 5 |
Page 6 |
Page 7 |
Page 8 |
Page 9 |
Page 10 |
Page 11 |
Page 12 |
Page 13 |
Page 14 |
Page 15 |
Page 16 |
Page 17 |
Page 18 |
Page 19 |
Page 20 |
Page 21 |
Page 22 |
Page 23 |
Page 24 |
Page 25 |
Page 26 |
Page 27 |
Page 28 |
Page 29 |
Page 30 |
Page 31 |
Page 32 |
Page 33 |
Page 34 |
Page 35 |
Page 36 |
Page 37 |
Page 38 |
Page 39 |
Page 40 |
Page 41 |
Page 42 |
Page 43 |
Page 44 |
Page 45 |
Page 46 |
Page 47 |
Page 48 |
Page 49 |
Page 50 |
Page 51 |
Page 52 |
Page 53 |
Page 54 |
Page 55 |
Page 56 |
Page 57 |
Page 58 |
Page 59 |
Page 60 |
Page 61 |
Page 62 |
Page 63 |
Page 64 |
Page 65 |
Page 66 |
Page 67 |
Page 68 |
Page 69 |
Page 70 |
Page 71 |
Page 72 |
Page 73 |
Page 74 |
Page 75 |
Page 76