ChE253MSp08 Expt04 ExampleRpt-2

ChE253MSp08 Expt04 ExampleRpt-2 - Statistical Process...

Info iconThis preview shows pages 1–5. Sign up to view the full content.

View Full Document Right Arrow Icon
Statistical Process Control Lab by Jenna Hartmann Submitted to Dr. C. G. Willson and Ian Mullet ChE 253M The University of Texas at Austin Fall 2007
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
2 Statistical Process Control Abstract The purpose of this lab was to employ statistical process control techniques to analyze a continuous mixing process in order to quantify the benefits of an in-line mixer. Statistical process control employed the use of control charts to determine if a flow control model was “in control” or “out of control”. X-bar and R charts created by an estimation and standard deviation method were used to analyze the benefits of the in-line mixer. The pre-mixer control charts show that the data follow a random but non-normal distribution and a wide range of variability (R-bar = 0.017). The post-mixer control charts show that the concentration data follows a non-random but normal distribution and a tighter range of variability (R-bar = 0.00069). Even though the data exiting the mixer was more statistically out of control than the mixture entering the mixer, the process capability was more acceptable for the exiting stream (pre-mixer Cp = 0.092 to post- mixer Cp =1.13); however, the Cp does not meet the required Cp of 1.3 for a capable process. The in-line mixture ensured production of a more reliable product, but it also required more engineering to optimize the process in an attempt to remove non random variation. Errors involved in this lab include autocorrelation, problems with the spectrometers and laminar flow, and possibility of dirt in the flow streams.
Background image of page 2
3 Contents Introduction 4 Methods 4 Results 6 Conclusions and Recommendations 1 5 Appendices Appendix A 17 Appendix B 19 Appendix C 21 References 2 2 List of Tables Table 1: Process Capability Index Values 14 List of Figures Figure 1: Process Flow Diagram 4 Figure 2: Pure Dye Pre-Mixer X-bar Chart, Estimation Method 6 Figure 3: Pure Dye Pre-Mixer R Chart 7 Figure 4: Pure Dye Post-Mixer X-bar Chart, Estimation Method 7 Figure 5: Pure Dye Post-Mixer R Chart 8 Figure 6: Mix Stream Pre-Mixer X-bar Chart, Estimation Method 9 Figure 7: Mix Stream Pre-Mixer R Chart 9 Figure 8: Pre-Mixer Distribution Histogram 10 Figure 9: Mix Stream Pre-Mixer X-bar Chart, Standard 11 Deviation Method Figure 10: Mix Stream Post-Mixer X-bar Chart, Estimation Method 12 Figure 11: Mix Stream Post-Mixer R Chart 12 Figure 12: Post-Mixer Distribution Histogram 13 Figure 13: Modified (plotted without outliers) Post-Mixer Histogram 13 Figure 14: Mix Stream Post-Mixer X-bar Chart, Standard 14 Deviation Method Figure 15: Pre- and Post-Mixer Raw Concentration Data 15
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full Document Right Arrow Icon
4 Statistical Process Control Introduction The purpose of this lab was to determine whether a continuous mixing process was “in control” by analyzing control charts and quantifying the benefits of an in-line mixer in the process. Statistical process control is a frequently used analytical tool for quality improvement programs. In this lab, the quality of the product stream (green dye and water solution) was
Background image of page 4
Image of page 5
This is the end of the preview. Sign up to access the rest of the document.

{[ snackBarMessage ]}

Page1 / 22

ChE253MSp08 Expt04 ExampleRpt-2 - Statistical Process...

This preview shows document pages 1 - 5. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online