Cross-Directional (CD) Mapping Tool—Excel Spreadsheet, Shared Access
The CD Mapping Tool is an Excel spreadsheet developed by the TAPPI Process Control Division’s Cross-Direction (CD) Mapping Common Interest Group (CIG). This tool is used to determine the mapping of CD actuators to the measurement profiles of interest.
This spreadsheet takes the output of a bump test (or other method) to develop both the best linear and 3rd order fit mapping models. In addition, comparison is made to the current map-in-use and a reference map (such as the previous map). Mapping Performance Indices (MPIs) are also provided to measure the accuracy of the map.
The spreadsheet provides:
- A standard display to view the results of a bump test. This display shows multiple bump tests (up to 3) on the same page, the map-in use, a reference map and the best fit linear and 3rd order maps.
- Mapping Performance Indices (MPIs) to provide a numerical measure of the accuracy of a map
- The ability to model mapping of CD actuators with non-uniform widths.
- Documentation of the changes in mapping over time. The spreadsheet can (and should be) stored after every bump test. Old maps can be shown as reference maps to document changes. MPIs can be used to show the accuracy of old maps with new bumps.
- A communications vehicle for papermakers and management. Results are graphed in an easy-to-understand format that is easy for non-process control professionals to understand
- Calculation and display of a sheet shrinkage profile. This is useful to investigate mapping changes and may be easier for some users to understand the underlying phenomenon.
- Improved edge mapping by treating the trim squirts as an actuator. This adds accuracy to 3rd order maps as the edge mapping points are not extrapolated outside of the bump points.
This product is ideal for:
Papermakers, commissioning engineers, process control engineers and software developers who are managing CD actuator mapping for CD sheet quality control applications.
Product is a downloadable excel spreadsheet. Includes an instructional manual (pdf).
CDMAPTOOLSITE - Shared Access (up to five users)
Also available for Single Users.
The information and data contained in this document were prepared by a technical committee of TAPPI. The committee and the Association assume no liability or responsibility in connection with the use of such information or data, including but not limited to any liability under patent, copyright, or trade secret laws. The user is responsible for determining that this document is the most recent edition published.