Kristian Martinsen

Statistical Process Control using Vectorial Tolerancing

There will always be a certain amount of systematic and random errors in a manufacturing process. Quality loss is kept at a minimum when the systematic error is minimal and the process is centred at nominal value. To achieve this, controlling the manufacturing process is vital. In Vectorial Tolerancing surface location and orientation is described with vectors in a Workpiece Coordinate System. Vectorial Tolerancing provides, as opposed to conventional tolerances, a clear distinction between the size, form, location, and orientation deviations. The magnitude and direction of each feature is therefore known. Deviations on these different features will have different causes and must be controlled separately. This paper shows how orientation and location of a surface can be controlled. Correction to the systematic process errors was done by mirroring the calculated mean values onto the nominal plane, and making a new NC-code for the milling machine with the mirrored planes as new nominal. Multivariate Statistical Process Control charts were used to keep the process in control. The results showed that Statistical Process Control of surface location and orientation using Vectorial Tolerancing is possible.

Social aspects of Plant monitoring and visualization

Monitoring and visualization of manufacturing plants can be both an aggregation of process monitoring to plant level as well as visualization of performance indicators and material flow. This paper contains a survey on 5 Norwegian manufacturing plants and suggestions on how to utilize of these systems for organizational learning and knowledge creation. The paper contains one in-depth case study on one of the plants.

Achieving a transparent and visual automotive value chain with ICT-support

Raufoss Chassis Technology (RCT) manufactures wheel suspension parts in aluminium for cars. Large volumes of identical parts, fully automated production lines combined with the extreme demands on speed, precision and quality makes fast response to changing demands important for the overall competitiveness. The manufacturing unit has been built and implemented based on Lean Manufacturing and Extended Enterprise Principles. The concept of extended enterprise is directly applicable, and provides a platform for understanding, discussion and decision. The need to establish basic principles prior to the development of solutions is important. The need for a common visual description of the value chain is vital. Showing the value chain, its partners and material flow, the information flow, the processes etc.