ISO TECHNICAL REPORT TR 10501 First edition 1993-12-15 Thermoplastics pipes for the transport of liquids under pressure Calculation of head losses Tubes en matieres thermoplastiques pour le transport de liquides sous pression --Calculdespertesdecharge [so Reference number ISO/TR 10501:1993(E) No reproduction or networking pemited without license from IHS Not for Resale ISO/TR10501:1993(E) Foreword of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subjectfor which a technical committee has been established has the right to be re presented on that committee. International organizations, governmental and non-governmental, in liaison with IsO, also take part in the work. IsO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization. The main task of technical committees is to prepare International Stan- tion of an International Standard, despite repeated efforts; for any other reason there is the future but not immediate possibility of an agreement on an International Standard; type 3, when a technical committee has collected data of a different kind from that which is normally published as an International Standard ("state of the art", for example). of publication, to decide whether they can be transformed into Interna- valid or useful. ISO/TR 10501, which is a Technical Report of type 3, was prepared by Technical Committee ISO/TC 138, Plastics pipes, fittings and valves for the transport of fluids, Sub-Committee Sc 2, Plastics pipes and fittings for watersupplies ISO1993 All rights reserved. No part of this publication may be reproduced or utilized in any form or by any means,electronic or mechanical, including photocopying and microfilm,without per- mission in writingfrom the publisher International Organization for Standardization CasePostale 56·CH-1211Geneve20·Switzerland Printed in Switzerland ii Standardizatior Not fr Resale TECHNICAL REPORT ISO/TR10501:1993(E) Thermoplastics pipes for the transport of liquids under pressure Calculation of head losses Scope 2.5 head loss, Ah : Change in pressure head between two sections of a horizontal pipe due to This Technical Report gives a method of liquid flow through the pipe. calculating head loss in the transport of liquids under pressure in hydraulically smooth 2.6 head drop, J : Head loss per unit length of thermoplastics pipes. pipe. The formulae given in the Technical Report apply 3 Symbols and units to the transport of water under pressure, or to all other liquids of the same dynamic viscosity, at The symbols and units used in this Technical temperatures of up to 45°C. Report are given in Table 1. 2 Definitions Table 1 For the purposes of this Technical Report, the Sub- Quantity Symbol Unit following definitions apply. clause 2.1 flowrate, qy : Volume of water flowing 2.1 Flowrate qv m3/h through the pipe per unit time. 2.3 Average velocity v m/s 2.4 Average internal 2.2steady flow : Flow in which the flowrate d m through a measuring section does not vary with diameter time. 2.5 Head loss Ah m 2.6 Head drop J m/m 2.3 average velocity, v : Flowrate through the pipe divided by the reference cross-section of the 4.1 Reynolds Re dimension- pipe. It is calculated by dividing the actual number less flowrate through the pipe by the cross-section of 4.1 Kinematic v m²/s the pipe. viscosity 2.4 reference cross-section of the pipe, A : 4.2 Pipe length 1 m Area of the circle with a diameter equal to the 4.3 Temperature of t average internal diameter of the pipe. The free liquid cross-sectional area of the pipe is calculated from the inside diameter of the pipe. 4.3 Temperature dimension- correction factor less No reproduction or networking permitted without li Not for Resale