Lafarge Process Kit - Dry weigt consistency ANALYSIS.pdf
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1. The document provides instructions for analyzing the dry weight consistency of consecutive plasterboards produced on a production line. It describes numbering boards, weighing them, and analyzing the data. 2. The data analysis includes calculating the mean, standard deviation, and performing a Fourier analysis to identify any periodic events that could be causing inconsistency issues. 3. Safety precautions are described, including having an operator near the emergency stop button during testing and wearing protective gloves when handling boards.
Lafarge Process Kit - Dry weigt consistency ANALYSIS.pdf
- 1. Lafarge Process Kit Methods Version 1 Direction Industrielle Direction Assistance des Procédés Dry Weight Consistency Analysis Page : 1/18 Date : February 13 th , 2007 © Copyright 2006, Lafarge Plâtres All rights reserved. No part of this document may be reproduced, stored in a retrieval system, translated, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without prior written permission of Lafarge Plâtres. CONFIDENTIAL The information contained herein is confidential and proprietary to Lafarge Plâtres. It may not be disclosed or transferred, directly or indirectly, to any third party without the explicit written permission of Lafarge Plâtres SUMMARY 1 PURPOSE............................................................................................................................. 1 2 FIELD OF APPLICATION...................................................................................................... 1 3 PRINCIPLE ........................................................................................................................... 2 4 PURPOSE............................................................................................................................. 5 4.1 Determination of normal cycles....................................................................................... 5 4.2 Causes of inconsistency ................................................................................................. 5 5 SAFETY................................................................................................................................. 5 6 EQUIPMENT ......................................................................................................................... 6 7 WORKING INSTRUCTIONS ................................................................................................. 7 7.1 Boards numbering .......................................................................................................... 7 7.2 Boards weighing ............................................................................................................. 7 7.3 Data analysis .................................................................................................................. 8 7.4 Examples.......................................................................................................................10 7.4.1 Theoretical..............................................................................................................10 7.4.2 Practical..................................................................................................................13 1 PURPOSE • Identify the root causes of inconsistency, 2 FIELD OF APPLICATION All LAFARGE Gypsum Division plasterboards production sites.
- 2. Lafarge Process Kit Methods Version 1 Direction Industrielle Direction Assistance des Procédés Dry Weight Consistency Analysis Page : 2/18 Date : February 13 th , 2007 © Copyright 2006, Lafarge Plâtres All rights reserved. No part of this document may be reproduced, stored in a retrieval system, translated, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without prior written permission of Lafarge Plâtres. CONFIDENTIAL The information contained herein is confidential and proprietary to Lafarge Plâtres. It may not be disclosed or transferred, directly or indirectly, to any third party without the explicit written permission of Lafarge Plâtres 3 PRINCIPLE Measure the dry weight of consecutive boards and analyze the data (standard deviation, Fourier analysis…). The minimum number of consecutive boards to collect depends on the speed of the line and the length of the boards. The sampling duration is at least 250 seconds and the minimum number of consecutives boards to collect is at least 100. The test has to be performed with the STD board of the country. In case of 2,5-meter long boards and for line speed up to 60m/mn, the minimum number of boards to collect is determined as follow : L V N × × = 60 250 With : o N : Number of boards to collect, o V : Line speed (m/mn), o L : Length of standard board (m). • Number of consecutive boards to collect with STD boards length of 2,5m. STD Speed line (m/mn) STD board length (m) Sampling duration (s) Minimum number of consecutive boards to collect 15 2,5 1000 100 20 2,5 750 100 25 2,5 600 100 30 2,5 500 100 35 2,5 429 100 40 2,5 375 100 45 2,5 333 100 50 2,5 300 100 55 2,5 273 100 60 2,5 250 100 65 2,5 250 108 70 2,5 250 117 75 2,5 250 125 80 2,5 250 133 85 2,5 250 142 90 2,5 250 150 95 2,5 250 158 100 2,5 250 167 105 2,5 250 175 110 2,5 250 183 115 2,5 250 192 120 2,5 250 200 125 2,5 250 208 130 2,5 250 217
- 3. Lafarge Process Kit Methods Version 1 Direction Industrielle Direction Assistance des Procédés Dry Weight Consistency Analysis Page : 3/18 Date : February 13 th , 2007 © Copyright 2006, Lafarge Plâtres All rights reserved. No part of this document may be reproduced, stored in a retrieval system, translated, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without prior written permission of Lafarge Plâtres. CONFIDENTIAL The information contained herein is confidential and proprietary to Lafarge Plâtres. It may not be disclosed or transferred, directly or indirectly, to any third party without the explicit written permission of Lafarge Plâtres • Number of consecutive boards to collect with STD boards length of 2m. STD Speed line (m/mn) STD board length (m) Sampling duration (s) Minimum number of consecutive boards to collect 5 2 2400 100 10 2 1200 100 15 2 800 100 20 2 600 100 25 2 480 100 30 2 400 100 35 2 343 100 40 2 300 100 45 2 267 100 50 2 250 104 55 2 250 115 60 2 250 125 65 2 250 135 70 2 250 146 75 2 250 156 80 2 250 167 85 2 250 177 90 2 250 188 95 2 250 198 100 2 250 208 105 2 250 219 110 2 250 229 115 2 250 240 120 2 250 250 125 2 250 260 130 2 250 271 135 2 250 281 140 2 250 292 145 2 250 302 150 2 250 313 155 2 250 323 160 2 250 333 165 2 250 344 170 2 250 354 175 2 250 365 180 2 250 375 185 2 250 385
- 4. Lafarge Process Kit Methods Version 1 Direction Industrielle Direction Assistance des Procédés Dry Weight Consistency Analysis Page : 4/18 Date : February 13 th , 2007 © Copyright 2006, Lafarge Plâtres All rights reserved. No part of this document may be reproduced, stored in a retrieval system, translated, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without prior written permission of Lafarge Plâtres. CONFIDENTIAL The information contained herein is confidential and proprietary to Lafarge Plâtres. It may not be disclosed or transferred, directly or indirectly, to any third party without the explicit written permission of Lafarge Plâtres • Number of consecutive boards to collect with STD boards length of 8 feet. STD Speed line (ft/mn) STD board length (ft) Sampling duration (s) Minimum number of consecutive boards to collect 16 8 2926 100 33 8 1463 100 49 8 975 100 66 8 732 100 82 8 585 100 98 8 488 100 115 8 418 100 131 8 366 100 148 8 325 100 164 8 293 100 180 8 250 100 197 8 250 103 213 8 250 111 230 8 250 120 246 8 250 128 262 8 250 137 279 8 250 145 295 8 250 154 312 8 250 162 328 8 250 171 344 8 250 179 361 8 250 188 377 8 250 197 394 8 250 205 410 8 250 214 427 8 250 222 443 8 250 231 459 8 250 239 476 8 250 248 492 8 250 256 509 8 250 265 525 8 250 273 541 8 250 282 558 8 250 290 574 8 250 299 591 8 250 308 607 8 250 316
- 5. Lafarge Process Kit Methods Version 1 Direction Industrielle Direction Assistance des Procédés Dry Weight Consistency Analysis Page : 5/18 Date : February 13 th , 2007 © Copyright 2006, Lafarge Plâtres All rights reserved. No part of this document may be reproduced, stored in a retrieval system, translated, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without prior written permission of Lafarge Plâtres. CONFIDENTIAL The information contained herein is confidential and proprietary to Lafarge Plâtres. It may not be disclosed or transferred, directly or indirectly, to any third party without the explicit written permission of Lafarge Plâtres 4 PURPOSE 4.1 Determination of normal cycles Even if the dry weigh consistency is excellent, good or usual (see “Dry weight consistency test” method), the Fourier analysis can help to determine the normal cycles, i.e. the intrinsic periodic events. 4.2 Causes of inconsistency In case of dry weight inconsistency (see “Dry weigh consistency test” method), the Fourier analysis can help to determine periodics events (fast or slow cycles which can be due to one default on plaster dosing belt, to the lack of one bucket in a bucket elevator…). 5 SAFETY The identification of the consecutives boards have to be performed just after the board cutter. To identify the plasterboards, the technician in charge of the test must be supported by one production operator who will be closed to the emergency stop button. Furthermore, besides the usual personal safety equipment, the technician must wear safety gloves.
- 6. Lafarge Process Kit Methods Version 1 Direction Industrielle Direction Assistance des Procédés Dry Weight Consistency Analysis Page : 6/18 Date : February 13 th , 2007 © Copyright 2006, Lafarge Plâtres All rights reserved. No part of this document may be reproduced, stored in a retrieval system, translated, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without prior written permission of Lafarge Plâtres. CONFIDENTIAL The information contained herein is confidential and proprietary to Lafarge Plâtres. It may not be disclosed or transferred, directly or indirectly, to any third party without the explicit written permission of Lafarge Plâtres 6 EQUIPMENT For the measurements, it is necessary to have : - One scale + 2 long steel bars to support boards (vertical scale is also possible) : - Manual method : Manual report + Excel calculation Sheet - Automatic method (optional) : One PC + acquisition system connected to the balance in order to record automatically weight : Remarks : Before each test, the scale has to be checked.
- 7. Lafarge Process Kit Methods Version 1 Direction Industrielle Direction Assistance des Procédés Dry Weight Consistency Analysis Page : 7/18 Date : February 13 th , 2007 © Copyright 2006, Lafarge Plâtres All rights reserved. No part of this document may be reproduced, stored in a retrieval system, translated, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without prior written permission of Lafarge Plâtres. CONFIDENTIAL The information contained herein is confidential and proprietary to Lafarge Plâtres. It may not be disclosed or transferred, directly or indirectly, to any third party without the explicit written permission of Lafarge Plâtres 7 WORKING INSTRUCTIONS 7.1 Boards numbering The boards numbering has to be done just after the board cutter and before the entrance into the dryer. Then, these plasterboards are getting back at the outlet of the bundler. Remarks : - During the measurement, it is necessary to have no process changes (constant line speed, mixer speed, receipt…) and to have an homogenous drying (see “moisture grid” method), - For high line speed plants (up to 70m/mn), if the manual numbering is too difficult to do, it is possible to use the electronic printing (grey side) on condition that the seconds are printed 7.2 Boards weighing The plasterboards are weighted and the weights are recorded in an Excel® compatible file.
- 8. Lafarge Process Kit Methods Version 1 Direction Industrielle Direction Assistance des Procédés Dry Weight Consistency Analysis Page : 8/18 Date : February 13 th , 2007 © Copyright 2006, Lafarge Plâtres All rights reserved. No part of this document may be reproduced, stored in a retrieval system, translated, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without prior written permission of Lafarge Plâtres. CONFIDENTIAL The information contained herein is confidential and proprietary to Lafarge Plâtres. It may not be disclosed or transferred, directly or indirectly, to any third party without the explicit written permission of Lafarge Plâtres 7.3 Data analysis The Thermicalc® Macro is necessary to analyse the data. In this Macro, choose the “data analysis” menu.
- 9. Lafarge Process Kit Methods Version 1 Direction Industrielle Direction Assistance des Procédés Dry Weight Consistency Analysis Page : 9/18 Date : February 13 th , 2007 © Copyright 2006, Lafarge Plâtres All rights reserved. No part of this document may be reproduced, stored in a retrieval system, translated, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without prior written permission of Lafarge Plâtres. CONFIDENTIAL The information contained herein is confidential and proprietary to Lafarge Plâtres. It may not be disclosed or transferred, directly or indirectly, to any third party without the explicit written permission of Lafarge Plâtres Complete the data analysis sheet as following : • « Main parameters » Button: o « Valeurs » : Select the column in Excel sheet where are recorded the dry weight values, o Select options as described above, o The step of the variogramm cannot be upper than the total number of boards : it is recommended to choose it equal to the half of the boards number • « Mean » Button: Choose cumulative, • « Fourier » Button: Choose « Number of sample » as abscissa and « logarithmic » as scale, • « Filtres et Filtres Niveau 1 » Button : Not applicable. Click “GO” Buton
- 10. Lafarge Process Kit Methods Version 1 Direction Industrielle Direction Assistance des Procédés Dry Weight Consistency Analysis Page : 10/18 Date : February 13 th , 2007 © Copyright 2006, Lafarge Plâtres All rights reserved. No part of this document may be reproduced, stored in a retrieval system, translated, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without prior written permission of Lafarge Plâtres. CONFIDENTIAL The information contained herein is confidential and proprietary to Lafarge Plâtres. It may not be disclosed or transferred, directly or indirectly, to any third party without the explicit written permission of Lafarge Plâtres 7.4 Examples 7.4.1 Theoretical Signal to analysis : -1,5 -1 -0,5 0 0,5 1 1,5 0 20 40 60 80 100 1. Cumulative mean and standard deviation
- 11. Lafarge Process Kit Methods Version 1 Direction Industrielle Direction Assistance des Procédés Dry Weight Consistency Analysis Page : 11/18 Date : February 13 th , 2007 © Copyright 2006, Lafarge Plâtres All rights reserved. No part of this document may be reproduced, stored in a retrieval system, translated, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without prior written permission of Lafarge Plâtres. CONFIDENTIAL The information contained herein is confidential and proprietary to Lafarge Plâtres. It may not be disclosed or transferred, directly or indirectly, to any third party without the explicit written permission of Lafarge Plâtres Data / Cumulative mean and standard deviation -1,5 -1 -0,5 0 0,5 1 1,5 0 20 40 60 80 100 120 Data / Cumulative mean 0 0,2 0,4 0,6 0,8 1 Cumulative standard deviation Raw values Cumulative mean Cumulative standard deviation Comments : The curves of these two parameters become stable quickly, which means that the sampling is homogeneous. 2. Variogramm Variogram 0 0,2 0,4 0,6 0,8 1 1,2 0 10 20 30 40 50 60 Step : h γ γ γ γ (h) n = 100 mini = -1,000 maxi = 1,000 m = -0,001 σ = 0,709 Reach = 1,635 σ0 = 0,000
- 12. Lafarge Process Kit Methods Version 1 Direction Industrielle Direction Assistance des Procédés Dry Weight Consistency Analysis Page : 12/18 Date : February 13 th , 2007 © Copyright 2006, Lafarge Plâtres All rights reserved. No part of this document may be reproduced, stored in a retrieval system, translated, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without prior written permission of Lafarge Plâtres. CONFIDENTIAL The information contained herein is confidential and proprietary to Lafarge Plâtres. It may not be disclosed or transferred, directly or indirectly, to any third party without the explicit written permission of Lafarge Plâtres Comments : The variogram is built by calculating the square average of the difference between every values spaced of one step (h). The curve describes these average according to the step. The variogram permits : - to show cycles, - to determine the minimum step to have two independent values. In the example, the variogram confirms that the signal is periodic. 3. Fourier analysis Fourier analysis 0 0,2 0,4 0,6 0,8 1 1,2 1 10 100 Number of values Comments : The Fourier analysis represents no matter signal as a sum of elementary trigonometric functions (Each function having a more or less high weighting coefficient). The graphic of this kind of analysis has got periods in X-axis (number of plasterboards in our case) and weighting coefficient in Y-axis. In our example, the Fourier analysis shows that there is only one periodic function (T=6 boards) which constitutes the signal.
- 13. Lafarge Process Kit Methods Version 1 Direction Industrielle Direction Assistance des Procédés Dry Weight Consistency Analysis Page : 13/18 Date : February 13 th , 2007 © Copyright 2006, Lafarge Plâtres All rights reserved. No part of this document may be reproduced, stored in a retrieval system, translated, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without prior written permission of Lafarge Plâtres. CONFIDENTIAL The information contained herein is confidential and proprietary to Lafarge Plâtres. It may not be disclosed or transferred, directly or indirectly, to any third party without the explicit written permission of Lafarge Plâtres 7.4.2 Practical 7.4.2.1 Plant A Boards numbers Dry weight (kg/m²) Mean (kg/m²) Standard deviation (kg/m²)
- 14. Lafarge Process Kit Methods Version 1 Direction Industrielle Direction Assistance des Procédés Dry Weight Consistency Analysis Page : 14/18 Date : February 13 th , 2007 © Copyright 2006, Lafarge Plâtres All rights reserved. No part of this document may be reproduced, stored in a retrieval system, translated, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without prior written permission of Lafarge Plâtres. CONFIDENTIAL The information contained herein is confidential and proprietary to Lafarge Plâtres. It may not be disclosed or transferred, directly or indirectly, to any third party without the explicit written permission of Lafarge Plâtres Comments : The cumulative mean and standard deviation show a no-stabilised situation, with a strong event around board N° 40, the quantity of boards to collec t has to be increase in order to determine if there is a slow cycle. The variogramm shows a main periodic (around 8 boards) signal. The Fourier analysis confirms that the signal is mainly composed of a 8 boards periodic function, but the second most important function has got a period near to 8 boards : Thus, the type of fluctuations could be Crenels or teeth of saw (sum of 2 sine functions with same periods). (Step)
- 15. Lafarge Process Kit Methods Version 1 Direction Industrielle Direction Assistance des Procédés Dry Weight Consistency Analysis Page : 15/18 Date : February 13 th , 2007 © Copyright 2006, Lafarge Plâtres All rights reserved. No part of this document may be reproduced, stored in a retrieval system, translated, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without prior written permission of Lafarge Plâtres. CONFIDENTIAL The information contained herein is confidential and proprietary to Lafarge Plâtres. It may not be disclosed or transferred, directly or indirectly, to any third party without the explicit written permission of Lafarge Plâtres 7.4.2.2 Plant B Boards numbers Dry weight (kg/m²)
- 16. Lafarge Process Kit Methods Version 1 Direction Industrielle Direction Assistance des Procédés Dry Weight Consistency Analysis Page : 16/18 Date : February 13 th , 2007 © Copyright 2006, Lafarge Plâtres All rights reserved. No part of this document may be reproduced, stored in a retrieval system, translated, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without prior written permission of Lafarge Plâtres. CONFIDENTIAL The information contained herein is confidential and proprietary to Lafarge Plâtres. It may not be disclosed or transferred, directly or indirectly, to any third party without the explicit written permission of Lafarge Plâtres Comments : The cumulative mean and standard deviation show that the samples are homogeneous (stable situation). The variogram shows that the main signal is a periodic (20 boards) damped signal. The Fourier analysis confirms that the main period is 20 but shows that a period of 16 is existing.
- 17. Lafarge Process Kit Methods Version 1 Direction Industrielle Direction Assistance des Procédés Dry Weight Consistency Analysis Page : 17/18 Date : February 13 th , 2007 © Copyright 2006, Lafarge Plâtres All rights reserved. No part of this document may be reproduced, stored in a retrieval system, translated, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without prior written permission of Lafarge Plâtres. CONFIDENTIAL The information contained herein is confidential and proprietary to Lafarge Plâtres. It may not be disclosed or transferred, directly or indirectly, to any third party without the explicit written permission of Lafarge Plâtres 7.4.2.3 Plant C Boards numbers Dry weight (kg/m²)
- 18. Lafarge Process Kit Methods Version 1 Direction Industrielle Direction Assistance des Procédés Dry Weight Consistency Analysis Page : 18/18 Date : February 13 th , 2007 © Copyright 2006, Lafarge Plâtres All rights reserved. No part of this document may be reproduced, stored in a retrieval system, translated, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise, without prior written permission of Lafarge Plâtres. CONFIDENTIAL The information contained herein is confidential and proprietary to Lafarge Plâtres. It may not be disclosed or transferred, directly or indirectly, to any third party without the explicit written permission of Lafarge Plâtres Comments : The situation is stabilised (cumulative mean and standard deviation). The variogram shows a mains periodic (12 boards) signal, confirmed by Fourier analysis. The Fourier analysis shows another periodic (10 boards) phenomenon but less important.