A Perspective View of the MODCON System
In this paper, a system of computer programs for the geometric description of hot forgings is outlined. The system is known as the MODCON system which stands for MODular CONstruction. The MODCON system allows quite complex forging shapes to be produced from relatively few input instructions. The forging geometry is defined as a series of volumetric modules which are then merged together during generation of the N.C. tape necessary to machine the finishing-cut EDM electrode for the whole forging cavity. The system can also be used for the roughing cut of the EDM electrode before the finishing cut stage as well as for generating cross-sectional data which serves as input to subsequent preform design systems. The system represents a considerable saving in time and cost over current methods involving conventional pattern making for the copy milling of electrodes.
Computer-aided manufacture of forging dies by volume building
Abstract A system of computer programs for the geomtric description of hot forging is outlined. The purpose of the system is (a) to facilitate the manufacture of EDM electrodes for forging dies with the aid of N.C. machining and (b) to generate input data for computer-aided preform design programmes. The forging geometry is defined as a series of simple volumetric modules which are merged together to form the whole shape required. This approach allows a wide range of forging shapes to be defined and machined, with relatively few simple input instructions. Examples of EDM electrones shaoes for typical forging manufactured with the aid of the system are shown. The N.C. tapes to machine such tapes are obtained after approximately 3 minutes computing time, preceded by not more than 30 minutes data preparation. This represents a considerable saving in time over current methods involving conventional pattern making for the copy milling of electrodes.
Robust solutions of inverse problems in electromagnetic non-destructive evaluation
Non-destructive testing (NDT) is the application of physical measurement technology based on energy interaction with the material and its nonconformities. The material's response is sensed by transducers and sensors which?in most cases?scan the component and document the results in inspection images. However, NDT measures a physically defined quantity or even an intrinsic property. The difference between non-destructive evaluation (NDE) and NDT is in the interpretation of the inspection data. NDE has to discuss the inspection results in terms of quality elements and characteristics which are relevant to describe the fitness of the material for use. In the case of macroscopic defects these are the kind of defect (cracklike, globular) and its size and orientation to the main stress directions; in the case of material property determination the parameters are mainly mechanical properties. Therefore, in NDE one has to solve inverse problems. The solution of inverse problems based on mathematical procedures such as integral equations is a strong developing discipline and most of the articles prepared for this special issue of the journal have the objective of discussing the latest state of the art in that field. However, practical NDE needs robust and quick solutions which are to be applied mainly online. Therefore, we present here inversion procedures based on multiple linear regression algorithms applied to inspection data. We describe the calibration procedure to fit the free parameters of the model functions and give examples of practical applications in industry.