1、STD-BSI PAS 27-ENGL 1qq7 II 1b24bL7 3781232 515 PAS 27:1999 Incorpomti?q? Corrigendum No. 1 PRODUCT ASSESSMENT SPECIFICATION Unplas ticized poly( vinyl chloride) alloy (PVC-A) pipes and bends for water under pressure ICs 23.040.20; 23.040.45,91.140.60 nl - -m u= NO COPYING WITHOUT BSI PERMISSION EXC
2、EPT AS PERMITTED BY COPYRIGKT LAW SiD;RSI PAS 27-ENGL 1999 Lb24bb”l 0783273 Li51 0 PAS 27:1999 hue 2, May 1999 on 15 May 1999 AmdNo. Date Text affected Q BSI 0519% 10516 Corrigendum I May 1999 1 Correction to quat Water UK. This Product Assessment Specification has beeen prepared and published by BS
3、I which retains its ownership and copyright. BSI reserves the right to withdraw or amend this Product Assessment Specification on receipt of authoritative advice that it is appropriate to do so. This Product Assessment Specification will be reviewed at intervals not exceeding 2 years and any amendme
4、nts arising from the review will be published in an amended Product Assessment Specification and publicized in Update Standards. This publication does not purport to include all necessary provisions of a contract. Users are responsible for its correct application. Compliance with a Product Assessmen
5、t Specification does not of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an inside front cover, pages i and ii, pages 1 to 23 and a back cover. 11 o RSI 03-1999 PAS 27:1999 Introduction During the finalization of this Product Assessment Speci
6、fication, from which further editions or a British Standard may be derived in due course, the following decisions, observations or proposals were made upon which comment is invited from users to assist amendment or updating of the contents as appropriate. a) The minimum wall thickness for pipes was
7、set at 3.0 mm (see Table i), compared with as little as 2.2 mm in the base documents considered and a suggestion that 3.2 mm should be specified to tolerate severe surface damage or abuse (at levels which would not be acceptable under relevant installation codes). b) The range of nominal pipe sizes
8、covered should be extended to include 710 and 800, with the corresponding values introduced into Tables 1,2 and 4 accordingly. c) For elastomeric seals, in addition to conformity to BS EN 681-1, attention is drawn to traditional UK requirements for resistance to microbiological degradation which cou
9、ld be invoked by contractual reference to BS 7874:1998 if and when this was considered essential. Opinions differed on whether it was appropriate to embody these requirements in this Product Assessment Specification so as to apply to seals for all the applications for which such pipes may be used. i
10、nstead of WIS 4-31-06: 1990, which has been superseded by a later edition which in turn refers to ISO/TR 9080. ISO/“R 9080:1992 is itself under revision and expected to result in a full International Standard, i.e. IS0 9080, during 1999. method for determination of C-ring toughness given in annex B,
11、 and referred to in annex Cy allows use of restraining rods as an option. Two considerations arise: d) For analysis of data for long-term properties, reference is made to ISOPTR 9080:1992 e) For consistency with existing British Standards and Water Industry Specifications, the 1) wherever alternativ
12、e test conditions may be used, one should be identified as the reference method in case of dispute (not necessarily the same one for all circumstances, e.g. one could be the reference method for some sizes and the other the reference method for the remaining sizes.) used to determine a performance v
13、alue but only the nature of the initial fracture mode, i.e. ductile or brittle. 2) for the purposes of this Product Assessment Specification, the test is not to be 1 Scope This Product Assessment Specification specifies the requirements for unplasticized poly(viny1 chloride)-based plastics alloy (PV
14、C-A) pipes, and PVC-A post-formed bends with integral joints, intended for the conveyance of drinking water under pressure. The pipes are intended for use below ground, and also above ground provided they are not exposed to direct sunlight. The pipes are suitable for service temperatures between O “
15、C and 40 “C. NOTE 1 At temperatures above 20 OC, pressure derating is necessary and should be in accordance with guidelines provided by the manufacturer. NOTE 2 If it is intended to use pipes conforming to this specification for the conveyance of fluids other than water, the manufacturer should be c
16、onsulted. NOTE 3 For any application involving surge and fatigue, reference should be made to the relevant UK Water Industry Information and Guidance Note il. For drinking water, the recommended temperature for rerating is 10 C. whereas for other fluids higher temperatures may be appropriate. NOTE 4
17、 PVC-A pressure pipes conforming to this specification, and associated fittings, should be installed and used in accordance with the manufacturers recommendations. o BSI 03-1999 1 SI;.BSI PAS 27-ENGL 1777 Lb24bh7 0781270 T33 PAS 27:1999 To assist arrangements for quality control or assessment of con
18、formity, annex A gives a classification for assigning each requirement and associated test to quality control or type test purposes respectively. 2 Normative references The following normative documents. contain provisions which, through reference in this text, constitute provisions of this Product
19、Assessment Specification. For dated references, subsequent amendments to, or revisions of, any of these publications do not apply. However, parties to agreements based on this Product Assessment Specification are encouraged to investigate the possibility of applying the most recent editions of the n
20、ormative documents indicated below. For undated references, the latest edition of the normative document referred to applies. BS 903-A!26, Physical testing of rubbers - Method A26: Method for determination of hardness (hardnesses between 10 IRHD and 110 IRHD). BS 2782-1l:Method 1101A, Measurement of
21、 dimensions of pipes. BS 7874:1998, Microbiological deterioration of elastomeric seals for joints in pipework and pipelines. BS EN 681-1:1996, Elastomeric seals - Materials requirements for pipe joint seals used in water and drainage applications - Part 1: Vulcanized rubber. IS0 1167:1996, Thermopla
22、stics pipes for the conveyance of fluids - Resistance to internal pressure - Test method. IS0 2505-1: 1994, Thermoplastic pipes - Longitudinal reversion - Part 1: Determination methods. IS0 2507-2, Thermoplastics pipes and fittings - Vicat softening temperature - Part 2: Test conditions for unplasti
23、cized poly(vinyl chloride) (PVC- U) or chlorinated poly(viny1 chloride) (PVC-C) pipes and fittings and for high-impact resistance poly(viny1 chloride) (PVC-HI) pipes. IS0 3127, Thermoplastics pipes - Determination of resistance to external blows - Round-the-clock method. IS0 5893:1993, Rubber and pl
24、astics test equipment - Tensile, flexural and compression types (constant rate of traverse) - Description. IS0 6259-1, Thermoplastics pipes - Determination of tensile properties - Part 1: General test method. IS0 6259-2:1997, Thermoplastics pipes - Determination of tensile properties - Part 2: Pipes
25、 made of unplasticized poly(viny1 chloride) (PVC- U), chlorinated poly(viny1 chloride) (PVC-C) and high- impact poly(viny1 chlorde) (PVC-HI). ISORR 9080:1992, Thermoplastics pipes for the transport of fluids - Methods of extrapolation of hydrostatic stress rupture data to determine the long-term hyd
26、rostatic strength of thermoplastics pipe materials. 3 Terms and definitions apply. For the purposes of this Product Assessment Specification the following terms and definitions 3.1 pipe batch clearly identifiable number of pipes, all of the same nominal size and nominal wall thickness, extruded from
27、 the same compound on the same machine NOTE The batch from which any pipe is made is identified by the pipe manufacturer, who also defines the size of a batch. 39 dude mode type of failure of the material where plastic deformation occurs, indicated, in the case of a fracture surface, by stress white
28、ning visible to correct vision without magnification PAS 27:1999 3.3 elevated temperature any temperature above 20 “C 3.4 hoop stress stress in a pipe under pressure, acting tangentially to the perimeter of a transverse section 3.5 hydrostatic design stress (HDS) (aHD) hoop stress due to internal hy
29、drostatic pressure that can be continuously applied at a specified temperature, derived by the application of a design factor to the extrapolated lower 97.5 % confidence limit of the mean long-term hydrostatic stress ( oLcL) 3.6 lower confidence limit long-term hydrostatic strength ( oUL) quantity,
30、with the dimensions of stress in megapascals (MPa), which can be considered as a property of the material and represents the 97.5 % lower confidence limit of the mean long-term strength at 20 “C for 50 years with internal water pressure 3.1 type test test intended to prove the suitability and perfor
31、mance of a new composition, a new processing technique or a new design or size of pipe NOTE Type tests are carried out when a change is made to a formulation or method of manufacture. 3.8 working pressure maximum pressure that can be sustained by the class of pipe for its estimated useful life under
32、 the expected working conditions 4 Symbols de,min. DN the nominal size e emin. PN P a, the minimum outside diameter of the pipe, in millimetres the pipe wall thickness, in millimetres minimum permissible wall thickness, in millimetres nominal working pressure designated in bar) the maximum allowable
33、 working pressure, in bar hydrostatic design stress, in megapascals NOTE Symbols used only in an annex are defined therein 5 Material PVC-A pipes shall consist of a poly(viny1 chloridel-based plastics alloy to which is added only those additives necessary to manufacture pipes, integral joints and po
34、st-formed bends which conform to this PAS. No reworked material, even of the same composition, shall be added to PVC-A pipes. NOTE The recommended colour for pipes and post-formed bends is blue within the range 18E51 ta 18353 of BS 4901:1976 but other colours may be used in accordance with the requi
35、rements of the purchaser, see note 2 to clause 1. 1) 1 bar = 10JN/m* = 0.1 MPa. O BSI 03-1999 3 STD-BSI PAS 27-ENGL 1999 W lbZ4bb7 D7aLZRU b1 PAS 27:1999 Issue 2, May 1999 6 Dimensions 6.1 General Dimensions shall be measured in accordance with BS 2782-1l:Method 1101A. 6.2 Pipes 61.1 Wall thickness
36、The wall thickness of pipes shall be calculated using the following equation de,. 200, +p emin. = where emin. P is the minimum wall thickness in millimetres (mm) (see Table i); is the internal pressure, in bar; de,min. oHD is the minimum outside diameter of the pipe, in millimetres (mm) (see Table i
37、); is the hydrostatic design stress, in megapascals (MPa). 61.2 Crr-rnfioncrz .Ctive length The effective length of the pipe shall be not less than that specified when measured at (23 * 2) “C or as agreed between the manufacturer and the purchaser. NOTE The coefficient of thermal expansion of PVC-A
38、may be taken as 7 x 69.4 Pip spigot ende Pipe spigot ends shall be normal to the main axis of the pipe. 6.2.5 Chumfirs Chamfered pipe ends shall conform to Figure 1. 6.3 Integral joints 6.3.1 Cmss-eectional dimenswns The inside diameter and the out-of-roundness shall conform to Table 2. The wall thi
39、ckness at any point of an integral socket, on the pressure side of the seal, shall be not less than the minimum wall thickness emin. specified for the pipe (see Table i). 6.3.2 Depth of engagement Spigotted pipe for elastomeric seal jointing shall be marked with an insertion (witness) mark such that, when the spigot is inserted into a matching pipe socket with the mark at the mouth of the socket, the joint shall be able to accommodate the expansion and contraction expected in service and shall conform to Table 2. K-I. 4 O BSI 05-1999
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