Rexroth Tightening System 350 System Documentation - Rhino ...

10 Working with the System Tightening Technology | Bosch Rexroth AG 305/31610.4 Results storage and statistics10.4.7.7 Xbar/s index cardThe colors used for the information in the histogram are described in the right section of the Histogramindex card.– Blue for ± 3σ (confidence range for the characteristic, 99.75% of all measurement values are locatedin the range of ± 3σ, see also Fig. 10–55 on page 291)– Red dashes for monitoring limits– Green dashes for intervention limits– Black dot and dash line for the average value.In addition, in the right section the you can see the numerical values for the selected characteristic 1, its3σ value, range, as well as the monitoring limits set in the tightening program.Figure 10–68: Xbar/s index cardThe position and distribution of characteristic 1 over a selected random sample scope are displayed onthis index card, thus indicating its trend. The average value, as well as the associated standard deviationfor characteristic 1 per selected sample scope, are depicted here. Changes in the course indicate changesto the process parameters and make it possible to implement measures to remedy systematic errorsin good time.The calculated average value for characteristic 1 per sample scope is depicted as a dot in the upper diagram.The standard deviation over the sample scope, and thus the spread (dispersion) of the measurementresults, is depicted in the lower diagram. If, for example, a sample scope of n = 5 has been set, theneach dot represents a sample with 5 successive values. The sample scope n can be set to between 5and 20.If the set sample scope has not been attained yet, a circle will appear instead of a filled-in dot.Intervention limits are depicted as green lines; tightening program monitoring limits are red lines. An upperintervention limit can be set for the standard deviation.In the right section of the Xbar/s index card, the results data for the most recent or selected tighteningis displayed.System 350 | 3 608 878 040/05.2008