ISO INTERNATIONAL STANDARD 8311 Second edition 2013-12-01 Refrigerated hydrocarbon and non- petroleum based liquefied gaseous fuels Calibration of membrane tanks and independent prismatic tanks in ships Manual and internal electro- optical distance-ranging methods Hydrocarbures refrigerés et combustibles gazeux liquéfies a base non pétroliere-Etalonnage des réservoirs a membrane et réservoirs pyramidaux - Méthodes manuelles et par mesurage électro-optique interne de la distance Reference number IS0 8311:2013(E) LSO @ IS0 2013 licensefrom IHS Not for Resale IS0 8311:2013(E) COPYRIGHTPROTECTEDDOCUMENT @ISO2013 All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized otherwise in any form written permission. Permission can be requested from either ISO at the address below or ISO's member body in the country of the requester. ISO copyright office Case postale 56:CH-1211 Geneva 20 Tel. + 41 22 749 01 11 Fax +4122 749 09 47 E-mail copyright@iso.org Web www.iso.org Published in Switzerland @ IS0 2013 - All rights reserved No reproductic Not for Resale IS0 8311:2013(E) Contents Page Foreword ..iv Introduction. ..V 1 Scope. ..1 2 Normative references ..1 3 Terms and definitions .1 4 Precautions .3 4.1 General .3 4.2 Ship's condition during calibration .3 4.3 Tank distortion. ..3 4.4 Comparison with drawings .4 4.5 Measurements by measuring tape 4 4.6 Measurements by electro-optical distance-ranging (EODR) instrument. .4 4.7 Conditionofmembrane ..5 4.8 Safety precautions for work in membrane tanks ..5 5 Equipment. ..5 6 Determination of measuring points ..6 7 Calibration by manual method ..6 7.1 General .6 7.2 Tank length measurement ..7 7.3 Tank width measurement. .9 7.4 Tank height measurement ..12 7.5 Measurement of bottom undulation and gauge reference height .14 7.6 Correction for temperature .15 Calibration by electro-optical distance-ranging (EODR) method .16 8.1 General .16 8.2 Setting up of EODR instrument .16 8.3 Calibration procedure ..17 9 Additional measurements .19 9.1 Location of level gauge ..19 9.2 Deadwood. ..19 10 Calculation .19 10.1 General .19 10.2 Calculation of tank volume 20 10.3 Effect of bottom undulation .20 10.4 Areaofchamferportion 20 10.5 Trim corrections .21 10.6 List corrections. 21 10.7 Combined trim and list corrections 21 10.8 Correction for tank shell expansion or contraction 21 11 Report and tables. .22 12 Recalibration .23 Annex A (informative) Uncertainty associated with tank calibration .24 Annex B (informative) Example of tank capacity table (Tank No.3) .36 Annex C (informative) Example of trim correction table (Tank No. 1) ..38 Annex D (informative) Example of list correction table (Tank No. 1) ..40 Bibliography ..42 iii ense with ISt ed without license from IHS Not for Resale