1、raising standards worldwideNO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBSI Standards PublicationBS ISO 19893:2011Plastics piping systems Thermoplastics pipes and fittings for hot and cold water Test method for the resistance of mounted assemblies to temperature cyclingBS IS
2、O 19893:2011 BRITISH STANDARDNational forewordThis British Standard is the UK implementation of ISO 19893:2011. The UK participation in its preparation was entrusted to T e c h n i c a l Committee PRI/88/4, Test Methods - Plastic Piping.A list of organizations represented on this committee can be ob
3、tained on request to its secretary.This publication does not purport to include all the necessary provisions of a contract. Users are responsible for its correct application. The British Standards Institution 2012 ISBN 978 0 580 64383 5 ICS 23.040.20; 23.040.45 Compliance with a British Standard can
4、not confer immunity from legal obligations.This British Standard was published under the authority of the Standards Policy and Strategy Committee on 31 January 2012.Amendments issued since publicationDate T e x t a f f e c t e dBS ISO 19893:2011Reference numberISO 19893:2011(E)ISO 2011INTERNATIONAL
5、STANDARD ISO19893First edition2011-12-15Plastics piping systems Thermoplastics pipes and fittings for hot and cold water Test method for the resistance of mounted assemblies to temperature cycling Systmes de canalisations en plastique Tubes thermoplastiques et raccords pour eau chaude et froide Mtho
6、de dessai de la rsistance des assemblages des cycles de temprature BS ISO 19893:2011ISO 19893:2011(E) COPYRIGHT PROTECTED DOCUMENT ISO 2011 All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form or by any means, electronic or mechanical
7、, including photocopying and microfilm, without permission in writing from either ISO at the address below or ISOs 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 + 41 22 749 09 47 E-mail copyrightiso.org Web www.iso.org
8、Published in Switzerland ii ISO 2011 All rights reservedBS ISO 19893:2011ISO 19893:2011(E) ISO 2011 All rights reserved iiiForeword ISO (the International Organization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International
9、 Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been established has the right to be represented on that committee. International organizations, governmental and non-governmental, in liaison with ISO, a
10、lso take part in the work. ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of electrotechnical standardization. International Standards are drafted in accordance with the rules given in the ISO/IEC Directives, Part 2. The main task of technical commit
11、tees is to prepare International Standards. Draft International Standards adopted by the technical committees are circulated to the member bodies for voting. Publication as an International Standard requires approval by at least 75 % of the member bodies casting a vote. Attention is drawn to the pos
12、sibility that some of the elements of this document may be the subject of patent rights. ISO shall not be held responsible for identifying any or all such patent rights. ISO 19893 was prepared by Technical Committee ISO/TC 138, Plastics pipes, fittings and valves for the transport of fluids, Subcomm
13、ittee SC 5, General properties of pipes, fittings and valves of plastic materials and their accessories Test methods and basic specifications. BS ISO 19893:2011BS ISO 19893:2011INTERNATIONAL STANDARD ISO 19893:2011(E) ISO 2011 All rights reserved 1Plastics piping systems Thermoplastics pipes and fit
14、tings for hot and cold water Test method for the resistance of mounted assemblies to temperature cycling 1 Scope This International Standard specifies a method for testing the resistance to temperature cycling of joints for piping systems with rigid or flexible thermoplastics pipes. It is applicable
15、 to thermoplastics piping systems intended to be used in hot and cold water pressure applications. 2 Principle A test assembly of pipes and fittings (see Figure 1) is subjected to temperature cycling by the passage of water under pressure using hot and cold water alternately, for a specified number
16、of cycles. While being subjected to temperature cycling, parts of the assembly of pipes and fittings are maintained under tensile stress and/or flexural strain using static clamps. During and after the test, the assembly is monitored for signs of leakage. NOTE It is assumed that the following test p
17、arameters are set by the reference product standard (i.e. the standard making reference to this International Standard): a) the test temperatures (see 3.1, 3.2 and 6.1); b) the duration of a complete cycle and each part of the cycle (see 3.1, 3.2 and 6.1); c) the test pressure (see 3.6 and 6.1); d)
18、the tensile stress (see 3.8 and 5.3); e) the bending radius (see Clause 4 and Figures 1 and 2); f) the total number of cycles, including the first five cycles (see 6.2 and 6.3). BS ISO 19893:2011ISO 19893:2011(E) 2 ISO 2011 All rights reservedKey 1 hot water reservoir 6 return pipe to reservoir (alt
19、ernative test assembly) 2 alternation equipment A branch A (anchored section) 3 cold water reservoir B branch B (section free to expand and contract) 4 balancing valves C branch C (bent pipe section) 5 tensioning device Figure 1 Test assembly of temperature cycling test 3 Apparatus 3.1 Cold water so
20、urce, capable of all of the following: a) supplying the water volume necessary to maintain the temperature variation throughout the test piece within the specified maximum difference (see 6.2); b) supplying this water at the lowest temperature specified in the reference product standard with an accu
21、racy of 2C; c) supplying this water for the duration of at least each cycle as specified in the reference product standard. If not specified otherwise in the reference product standard, to an accuracy of the duration time of 10minute(s). BS ISO 19893:2011ISO 19893:2011(E) ISO 2011 All rights reserve
22、d 33.2 Hot water source, capable of all of the following: a) supplying the water volume necessary to achieve the required water velocity (see 6.2); b) supplying this water at the highest temperature specified in the reference product standard to an accuracy of 2C; c) supplying this water for the dur
23、ation of at least each cycle as specified in the reference product standard. If not specified otherwise in the reference product standard, to an accuracy of the duration time of 10minute(s). 3.3 Balancing valves, capable of regulating the water velocity as necessary to maintain the temperature varia
24、tion throughout the test piece within the specified maximum difference (see 6.2). 3.4 Alternation equipment, capable of achieving each change in hot and cold water temperatures at the inlet within 1 min. 3.5 Thermometer(s), capable of checking conformity to the specified test temperatures (see 3.1,
25、3.2 and 6.2). 3.6 Pressure gauge(s) and a device, for regulating the water pressure in the test assembly at the pressure specified in the reference product standard to an accuracy of 0,5 bar1)( 0,05 MPa), except for brief pressure spikes, which can occur if the temperature of water is changed. 3.7 S
26、upporting brackets, as appropriate, comprising anchor brackets (fixed points) capable of restraining piping components and guide brackets, capable of supporting piping components without inhibiting longitudinal movement (see Clause 5 and Figure 1). 3.8 Tensioning device, capable of applying the requ
27、ired initial tensile stress (see 5.3). NOTE This is to simulate stress which can be induced in any fixed pipe section as a result of contraction caused by cooling to temperatures below those prevailing during installation. 4 Test assembly The test assembly shall comprise an assembly of pipes and fit
28、tings jointed and clipped in accordance with Figure 2 and the manufacturers recommended practice, except as follows. If, while following the manufacturers recommended practice, the pipe cannot be bent to the configuration shown for branch C in Figure 2, for instance, because of the material, wall th
29、ickness and/or outside diameter of the pipe, branch C shall conform to Figure 3. The test assembly as shown in Figure 2 shall include the following: a) for branch A: at least three prestressed pipes linked by straight connectors, stressed in accordance with 5.3, where the free length of such combina
30、tion shall be (3 000 100) mm; b) for branch B: at least two straight pipes, each free to move and having a minimum free length of (300 10) mm; c) for branch C: at least one bend (see Figure 2 or 3, as appropriate) supported by ends. The free length of pipe shall either be in the range of 27dnto 28dn
31、, where dnis the nominal diameter of the pipe or alternatively, shall have a length which enables the minimum pipe bending radius, as stated by the manufacturer, to be formed. Unless specified by the product standard or agreed between parties, the bending radius shall be 6de. 1) 1 bar 0,1 MPa 105Pa;
32、 1 MPa 1 N/mm2. BS ISO 19893:2011ISO 19893:2011(E) 4 ISO 2011 All rights reservede5 Preparation of the test assembly 5.1 If applicable, subject the test assembly to preconditioning in accordance with the recommendations of the manufacturer(s) of piping components and/or the jointing components (e.g.
33、 adhesive). 5.2 Condition the test assembly at a room temperature of (23 2) C for at least 1 h. 5.3 Prestress branch A of the test assembly to the tensile stress specified in the reference product standard and fix in position the free ends of the stressed branch. EXAMPLE Dimension of the pipe: 32 3
34、mm. Tensile stress according to the reference product standard: t 2 MPa 2 N/mm2. Equation for the circular ring area: 22nn0,25 ( 2 )Add(1) where A circular ring area, expressed in square millimetres (mm2); dnoutside diameter, expressed in millimetres (mm); e wall thickness, expressed in millimetres
35、(mm). 2220,25 32 (32 6) 273mmA Equation for the tensile force: F t A 2 273 546 N (2) This is equal to an applied mass of 56 kg. Unfasten the fixed straight connector on the downstream side of branch A, charge branch A with the tensile force of 546 N (e.g. with a weight of 56 kg) on a bowden cable. T
36、ighten the fixed straight connector again. From that moment, the pre-stress in branch A is preset and the weight can be removed. 5.4 Fill the test assembly with cold water so that all air is expelled. 6 Procedure 6.1 Start the sequence of cycles, of cold and then hot water, specified in the referenc
37、e product standard see b) of the note to Clause 2 under the conditions of pressure and temperatures applicable to the class of service conditions as specified in the reference product standard. The ambient air temperature, Ta,air, during the whole testing time shall be: 20 C Ta,air 35 C. Unless spec
38、ified otherwise in the relevant system standard referring to this particular diameter range, the following settings shall be used for diameters smaller than 63 mm: duration of a complete cycle: 3020minutes; duration of the cold cycle: 1510minutes; duration of the hot cycle: 1510minutes; total number
39、 of cycles: 5 000. BS ISO 19893:2011ISO 19893:2011(E) ISO 2011 All rights reserved 56.2 Within the first five cycles: a) adjust the balancing valve(s) so that for the remainder of the test, during each part of the water cycle where a temperature is to be maintained, the temperature drop between the
40、inlet and the outlet of the test assembly is less than 5 C; b) perform any tightening or adjustment of joints necessary to eliminate any leakage; c) adjust the pressure control devices so that for the remainder of the test, the specified test pressure is maintained. 6.3 Throughout and following comp
41、letion of the number of cycles specified by the reference product standard, inspect all joints for any signs of leakage, e.g. scaling. If leakage occurs, record the type and position of the leakage and when it was observed. 6.4 In the test arrangement for diameters larger than 63 mm (depicted in Fig
42、ure 4), the cycle times are usually increased in order to maintain a stable and reproducible temperature profile. If problems occur with the temperature control, especially with the alternation time ( 1 min at the inlet) or the constancy of the temperature, alternative durations shall be used. Unles
43、s specified otherwise in the relevant system standard referring to this particular diameter range, the following settings shall be used for diameters larger than 63 mm: duration of a complete cycle: 6020minutes; duration of the cold cycle: 3010minutes; duration of the hot cycle: 3010minutes; total n
44、umber of cycles: 2 500. 7 Test report The test report shall include the following information: a) a reference to this International Standard, i.e. ISO 19893:2011, and to the reference product standard; b) the material and other identification of the components under test, including the class of serv
45、ice condition and the operating pressure; c) whether the pipe was flexible or rigid; d) the tensile stress in branch A; e) the inlet and outlet temperatures (lower and higher temperature of the cycle), in degrees Celsius; f) the duration of the complete cycle and each part of the cycle, in minutes;
46、g) the total number of complete cycles, (including the first five cycles); h) the test pressure, in bars; i) signs of leakage, if any, and where and when it occurred; j) any factors that can have affected the results, such as any incident or operating details not specified in this International Stan
47、dard; BS ISO 19893:2011ISO 19893:2011(E) 6 ISO 2011 All rights reservedk) the date of test; l) minimum, maximum and average ambient air temperature. Dimensions in millimetres Key A branch A (anchored section) B branch B (section free to expand and contract) C branch C (cold bent pipe section) fixed
48、straight connector straight connector pipe with guide free pipe supported elbow (moves freely) fixed elbow elbow Figure 2 Test arrangement BS ISO 19893:2011ISO 19893:2011(E) ISO 2011 All rights reserved 7Key C* branch C (for rigid pipes) fixed straight connector straight connector free pipe fixed el
49、bow elbow Figure 3 Alternative test arrangement of branch C for rigid pipes BS ISO 19893:2011ISO 19893:2011(E) 8 ISO 2011 All rights reservedKey fixed straight connector straight connector pipe with guide free pipe fixed elbow aMinimum length of each pipe section 1202. 00Figure 4 Alternative test arrangement of branch B for diameters larger than 63 mm (no prestress) BS ISO 19893:2011BS ISO 19893:2011ISO 19893:
