1、 Collection of SANS standards in electronic format (PDF) 1. Copyright This standard is available to staff members of companies that have subscribed to the complete collection of SANS standards in accordance with a formal copyright agreement. This document may reside on a CENTRAL FILE SERVER or INTRA
2、NET SYSTEM only. Unless specific permission has been granted, this document MAY NOT be sent or given to staff members from other companies or organizations. Doing so would constitute a VIOLATION of SABS copyright rules. 2. Indemnity The South African Bureau of Standards accepts no liability for any
3、damage whatsoever than may result from the use of this material or the information contain therein, irrespective of the cause and quantum thereof. ISBN 978-0-626-23575-8 SANS 1808-18:2010Edition 1.2SOUTH AFRICAN NATIONAL STANDARD Water supply and distribution system components Part 18: PVC-U gate va
4、lves Published by SABS Standards Division 1 Dr Lategan Road Groenkloof Private Bag X191 Pretoria 0001 Tel: +27 12 428 7911 Fax: +27 12 344 1568 www.sabs.co.za SABS SANS 1808-18:2010 Edition 1.2 Table of changes Change No. Date Scope Amdt 1 2004 Amended to update the list of parts, to redefine “accep
5、table“, to remove reference to the certification mark, and to update the referenced standards. Amdt 2 2010 Amended to update the list of parts in the foreword, to update referenced standards, and to modify the design requirements. Foreword This South African standard was approved by National Committ
6、ee SABS SC 138G, Water supply and sanitation Equipment and systems Plumbing components, in accordance with procedures of the SABS Standards Division, in compliance with annex 3 of the WTO/TBT agreement. This document was published in April 2010. This document supersedes SANS 1808-18:2004 (edition 1.
7、1). A vertical line in the margin shows where the text has been technically modified by amendment No. 2. SANS 1808 consists of the following parts, under the general title Water supply and distribution system components: Part 2: Metallic compression type pipe couplings. Part 5: Flexible connectors.
8、Part 8: Tap converters (copper alloy bodies). Amdt 1 Part 9: Metering taps and valves (metallic bodies). Part 10: Copper alloy check valves (spring-loaded). Part 13: Diaphragm valves. Amdt 1 Part 15: Mechanical backflow-prevention devices. Amdt 1 Part 16: Drinking fountain taps. Part 18: PVC-U gate
9、valves. Part 24: Gas-operated water heaters. Part 30: Laboratory water taps. Part 31: Automatic control valves. Part 32: Float valves (equilibrium type). Part 35: Electronically operated taps and valves. SANS 1808-18:2010 Edition 1.2 1 Foreword (concluded) Part 37: Single-control mixer taps (plastic
10、s). Part 44: Pipe saddles. Part 45: Pipe repair clamps. Part 53: Drain cocks for hot-water storage containers. Part 58: In-line strainers. Part 66: Demand type water taps. Part 85: Oriented polyvinyl chloride (PVC-O) pressure pipes for underground use. Amdt 1; amdt 2 Annex A forms an integral part o
11、f this document. Annexes B and C are for information only. SANS 1808-18:2010 Edition 1.2 2 Contents Page Foreword 1 Scope . 3 2 Normative references . 3 3 Definitions 3 4 Requirements . 4 5 Inspection and method of test . 5 5.1 Inspection. 5 5.2 Performance test 5 6 Marking . 6 Annex A (normative) N
12、ote to purchasers . 7 Annex B (informative) Quality verification of PVC-U gate valves . 7 Annex C (informative) Bibliography 8 SANS 1808-18:2010 Edition 1.2 3 Water supply and distribution system components Part 18: PVC-U gate valves 1 Scope This part of SANS 1808 specifies requirements for PVC-U ga
13、te valves of nominal size 50 mm to 250 mm, that are intended for use in general water installations at temperatures that do not exceed 30 C and at working pressures of 1 000 kPa or 1 600 kPa. NOTE This part of SANS 1808 is not applicable to valves intended for use in waterworks. 2 Normative referenc
14、es The following standards contain provisions which, through reference in this text, constitute provisions of this part of SANS 1808. All standards are subject to revision and, since any reference to a standard is deemed to be a reference to the latest edition of that standard, parties to agreements
15、 based on this part of SANS 1808 are encouraged to take steps to ensure the use of the most recent editions of the standards indicated below. Information on currently valid national and international standards can be obtained from the SABS Standards Division. ISO 7508, Unplasticized polyvinyl chlori
16、de (PVC-U) valves for pipes under pressure Basic dimensions Metric series. Amdt 2 SANS 1109-1/ISO 7-1, Pipe threads where pressure-tight joints are made on the threads Part 1: Dimensions, tolerances and designation. SANS 1123, Pipe flanges. Amdt 1 3 Definitions For the purposes of this part of SANS
17、1808, the following definitions apply: 3.1 acceptable acceptable to the authority administering this standard, or to the parties concluding the purchase contract, as relevant Amdt 1 3.2 agreed agreed upon between the manufacturer and the purchaser SANS 1808-18:2010 Edition 1.2 4 4 Requirements 4.1 M
18、aterials 4.1.1 Plastics materials The type and quality of the material of a plastics component part shall be such as to ensure a) the acceptable performance and durability of the component under normal operating conditions, and b) that, when the product is subjected to a temperature of 150 C 5 C in
19、an air-circulating oven for 60 min 5 min, there is no sign of blistering of the material or weld-line splitting of any component part. Any damage around the injection point shall not have penetrated to a depth of more than 50 % of the thickness of the material at that point. 4.1.2 Rubber materials T
20、he rubber used for component parts shall be of acceptable quality. 4.2 Working pressure rating The design pressure rating of the valve shall be such that the valve can tolerate a working pressure of 1 000 kPa or 1 600 kPa, as agreed upon (see annex A). 4.3 Design The valve shall comply with the requ
21、irements given below. Amdt 2 4.4 Stem The stem shall be of the rising or the non-rising type, as agreed upon (see annex A). 4.5 Stem cap The design of the stem cap shall be as agreed upon (see annex A). 4.6 Attachment between stem top and stem cap The stem cap shall be attached to the stem by means
22、of a shear pin of such strength that, when tested in accordance with 5.2.2.10, the shear pin fails at a torque of not less than the appropriate value given in column 3 of table 1 but at not more than 10 % in excess of this value. 4.7 Direction of closing The valve shall be closed by operating the st
23、em in the clockwise direction. 4.8 End connections End connections shall be a) flanged, and the dimensions of the flange shall comply with the appropriate of those given in SANS 1123, except for the thickness of the flange which shall conform to an agreed standard (see annex A); SANS 1808-18:2010 Ed
24、ition 1.2 5 b) double socketed, and the dimensions of the socket shall conform to an agreed standard (see annex A); or c) in the case of sizes 50 mm, 65 mm, 80 mm and 100 mm, threaded, if so agreed (see annex A), and the thread shall comply with SANS 1109-1. 4.9 Strength of construction When a valve
25、 is tested in accordance with a) 5.2.2.3, no part of the body or gate shall fail, b) 5.2.2.5, there shall be no leakage at the gate seat, c) 5.2.2.7, the valve body shall not fail, in any way, d) 5.2.2.8, there shall be no failure of the valve, e) 5.2.2.9, there shall be no failure of the valve, and
26、 f) 5.2.2.10, the shear pin shall fail. Table 1 Closing torque 1 2 3 Size of valve Closing torque Minimum torque mm Nm 10 Nm Nm 50 80 100 125 150 150 150 190 300 300 300 300 150 200 225 250 225 300 340 375 450 600 675 750 5 Inspection and method of test 5.1 Inspection Inspect each PVC-U gate valve f
27、or compliance with those requirements of this part of SANS 1808 for which tests to assess compliance are not given in 5.2. 5.2 Performance test 5.2.1 Apparatus 5.2.1.1 Water supply, at a pressure that can be adjusted up to 3 200 kPa. 5.2.1.2 Calibrated pressure gauge. 5.2.1.3 Calibrated torque wrenc
28、h, of capacity as given in column 3 of table 1, appropriate to the size of valve given in column 1. SANS 1808-18:2010 Edition 1.2 6 5.2.2 Procedure 5.2.2.1 Connect the water supply to one end of the valve and attach the pressure gauge. 5.2.2.2 Close the valve fully and increase the water pressure to
29、 a pressure equal to 1,5 times the working pressure of the valve. 5.2.2.3 Maintain this pressure for 5 min and while the valve is under pressure, inspect the valve body and valve gate for compliance with 4.9(a). 5.2.2.4 Open the valve and then close it by applying to the stem a torque of value equal
30、 to the value given in column 2 of table 1, appropriate to the size of valve given in column 1. 5.2.2.5 Increase the water pressure to 1,1 times the working pressure, maintain this pressure for 5 min and check the opposite side of the gate for compliance with 4.9(b). 5.2.2.6 Blank off the open end o
31、f the valve, open the valve and fill the valve, ensuring that no air is entrapped. 5.2.2.7 Increase the water pressure to twice the working pressure, maintain this pressure for 5 min and while the valve is under pressure, check the valve body for compliance with 4.9(c). 5.2.2.8 Remove the water supp
32、ly and apply to the stem a closing torque equal to the value given in column 3 of table 1, appropriate to the size of valve given in column 1. Maintain this torque for 5 min and then check the valve for compliance with 4.9(d). 5.2.2.9 Fix the gate in the half-open position in the valve and apply to
33、the stem an opening torque equal to the value given in column 3 of table 1, appropriate to the size of valve given in column 1. Maintain this torque for 5 min and then check the valve, for compliance with 4.9(e). 5.2.2.10 Close the valve and apply to the stem top a torque appropriate to that given i
34、n 4.6. Check for compliance with the requirements of 4.9(f). 6 Marking The following information shall appear in legible and indelible marking in a visible position on the body of each gate valve: a) the manufacturers name, trade name or trade mark; b) the nominal size, in millimetres; and c) the wo
35、rking pressure, in kilopascals. SANS 1808-18:2010 Edition 1.2 7 Annex A (normative) Note to purchasers The following requirements shall be agreed upon between the supplier and the purchaser: a) the working pressure (see 4.2); b) the type of stem (see 4.4); c) the design of the stem cap (see 4.5); d)
36、 the standard applicable to the thickness of the flange (see 4.8(a); e) the standard applicable to the thickness of the socket (see 4.8(b); and f) whether the end connections shall be threaded (see 4.8(c). Annex B (informative) Quality verification of PVC-U gate valves B.1 When a purchaser requires
37、ongoing verification of the quality of PVC-U gate valves, it is suggested that, instead of concentrating solely on evaluation of the final product, he also direct his attention to the manufacturers quality system. In this connection it should be noted that SANS 9001 covers the provision of an integr
38、ated quality system. B.2 If no information about the implementation of quality control or testing during manufacture is available to help in assessing the quality of a lot, and a purchaser wishes to establish, by inspection and testing of samples of the final product, whether a lot of the PVC-U gate
39、 valves complies with this part of SANS 1808, an acceptable sampling plan should be agreed upon between the supplier and the purchaser. It should be noted that a) such a sampling plan applies to fully manufactured PVC-U gate valves only, and b) a lot that, in terms of the sampling plan, is deemed to
40、 comply with this part of SANS 1808 could contain defective PVC-U gate valves to an extent proportional to that permitted by the relevant acceptance number given in the agreed sampling plan. SANS 1808-18:2010 Edition 1.2 8 Annex C (informative) Bibliography SANS 9001/ISO 9001, Quality management sys
41、tems Requirements. Amdt 1 SABS SABS Standards Division The objective of the SABS Standards Division is to develop, promote and maintain South African National Standards. This objective is incorporated in the Standards Act, 2008 (Act No. 8 of 2008). Amendments and Revisions South African National Sta
42、ndards are updated by amendment or revision. Users of South African National Standards should ensure that they possess the latest amendments or editions. The SABS continuously strives to improve the quality of its products and services and would therefore be grateful if anyone finding an inaccuracy
43、or ambiguity while using this standard would inform the secretary of the technical committee responsible, the identity of which can be found in the foreword. Tel: +27 (0) 12 428 6666 Fax: +27 (0) 12 428 6928 The SABS offers an individual notification service, which ensures that subscribers automatic
44、ally receive notification regarding amendments and revisions to South African National Standards. Tel: +27 (0) 12 428 6883 Fax: +27 (0) 12 428 6928 E-mail: salessabs.co.za Buying Standards Contact the Sales Office for South African and international standards, which are available in both electronic
45、and hardcopy format. Tel: +27 (0) 12 428 6883 Fax: +27 (0) 12 428 6928 E-mail: salessabs.co.za South African National Standards are also available online from the SABS website http:/www.sabs.co.za Information on Standards The Standards Information Centre provides a wide range of standards-related in
46、formation on both national and international standards, and is the official WTO/TBT enquiry point for South Africa. The Centre also offers an individual updating service called INFOPLUS, which ensures that subscribers automatically receive notification regarding amendments to, and revisions of, inte
47、rnational standards. Tel: +27 (0) 12 428 6666 Fax: +27 (0) 12 428 6928 E-mail: infosabs.co.za Copyright The copyright in a South African National Standard or any other publication published by the SABS Standards Division vests in the SABS. Unless exemption has been granted, no extract may be reprodu
48、ced, stored in a retrieval system or transmitted in any form or by any means without prior written permission from the SABS Standards Division. This does not preclude the free use, in the course of implementing the standard, of necessary details such as symbols, and size, type or grade designations. If these details are to be used for any purpose other than implementation, prior written permission must be obtained. Details and advice can be obtained from the Senior Manager. Tel: +27 (0) 12 428 6666 Fax: +27 (0) 12 428 6928 E-mail: infosabs.co.za
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