1、BRITISH STANDARD BS ISO 11922-2:1997 Thermoplastics pipes for the conveyance of fluids Dimensions and tolerances Part 2: Inch-based series ICS 23.040.20BSISO 11922-2:1997 This British Standard, having been prepared under the directionof the Sector Board forMaterials and Chemicals, waspublished under
2、 the authorityof the Standards Boardand comes into effect on 15June1997 BSI 09-1999 ISBN 0 580 27768 2 National foreword This British Standard reproduces verbatim ISO11922-2:1997and implements it as the UK national standard. This British Standard, together with BS2782-11:Method1121C (identical to IS
3、O161-2) and BS ISO4065, partially supersedes BS3867:1987, which becomes obsolescent and retained only to support existing British Standards. The UK participation in its preparation was entrusted to Technical Committee PRI/61, Plastics piping systems and components, which has the responsibility to: a
4、id enquirers to understand the text; present to the responsible international/European committee any enquiries on the interpretation, or proposals for change, and keep the UK interests informed; monitor related international and European developments and promulgate them in the UK. A list of organiza
5、tions represented on this committee can be obtained on request to its secretary. Cross-references The British Standards which implement international or European publications referred to in this document may be found in the BSI Standards Catalogue under the section entitled “International Standards
6、Correspondence Index”, or using the “Find” facility of the BSI Standards Electronic Catalogue. A British Standard does not purport to include all the necessary provisions of a contract. Users of British Standards are responsible for their correct application. Compliance with a British Standard does
7、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, theISO title page, pages ii to iv, pages 1 to 10 and a back cover. This standard has been updated (see copyright date) and may have had amendments inco
8、rporated. This will be indicated in the amendment table on the inside front cover. Amendments issued since publication Amd. No. Date CommentsBSISO 11922-2:1997 BSI 09-1999 i Contents Page National foreword Inside front cover Foreword iii Text of ISO 11922-2 1ii blankBSISO 11922-2:1997 ii BSI 09-1999
9、 Contents Page Foreword iii Introduction 1 1 Scope 1 2 Normative reference 1 3 Definitions 1 4 Tolerances on outside diameters 2 5 Tolerances on wall thickness 3 6 Measurement of dimensions 7 Annex A (informative) Bibliography 10 Table 1 Tolerances on mean outside diameters Inch-based series 3 Table
10、 2 Tolerances on out-of-roundness Inch-based series 3 Table 3 Tolerances on wall thickness at any point Grade T 5 Table 4 Tolerances on wall thickness at any point Grade U 6 Table 5 Tolerances on wall thickness at any point Grade V 7 Table 6 Tolerances on mean wall thickness Grade W 8 Table 7 Tolera
11、nces on mean wall thickness Grade X 9 Descriptors: Fluid pipelines, pipes (tubes), thermoplastic resins, plastic tubes, form specifications, dimensions, diameters, thickness, dimensional tolerances, form tolerances, imperial system.BSISO 11922-2:1997 BSI 09-1999 iii Foreword ISO (the International O
12、rganization for Standardization) is a worldwide federation of national standards bodies (ISO member bodies). The work of preparing International Standards is normally carried out through ISO technical committees. Each member body interested in a subject for which a technical committee has been estab
13、lished has the right to be represented 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 standardizat
14、ion. 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 least75% of the member bodies casting a vote. International Standard ISO11922-2was prepared by Technical Committee I
15、SO/TC138, Plastics pipes, fittings and valves for the transport of fluids. Together with ISO11922-1, it cancels and replaces ISO3606:1976, ISO3607:1977, ISO3608:1976and ISO3609:1977. ISO11922consists of the following parts, under the general title Thermoplastics pipes for the conveyance of fluids Di
16、mensions and tolerances: Part1: Metric series; Part2: Inch-based series. Annex A of this part of ISO11922is for information only.iv blankBSISO 11922-2:1997 BSI 09-1999 1 Introduction In the past, International Standards specifying the tolerances to be applied to thermoplastics pipes have covered ind
17、ividual materials separately. The philosophy of ISO11922is to combine these already published standards into a single two-part standard covering the tolerances for extruded pipes manufactured from all thermoplastics materials, thus avoiding the need for a standard to be developed for each individual
18、 material. ISO11922therefore contains a number of tolerance grades covering the mean outside diameter, the out-of-roundness of the outside diameter, the wall thickness at any point and the mean wall thickness. The bodies responsible for writing the various product and system standards will choose, f
19、rom the specified tolerance grades, that grade which is suitable for the application and material involved. 1 Scope This part of ISO11922specifies tolerance grades for the outside diameter, out-of-roundness and wall thickness of inch-based thermoplastics pipes for the conveyance of fluids and manufa
20、ctured with nominal outside diameters and nominal pressures in accordance with ISO161-211 (seeAnnex A). It is applicable to smooth thermoplastics pipes of constant circular cross-section along the whole length of the pipe, whatever the method of manufacture, the pipe material or the intended applica
21、tion. NOTEIt is intended that the tolerance grades specified in product standards be selected from this part of ISO11922, taking into account the material and the intended application. 2 Normative reference The following standard contains provisions which, through reference in this text, constitute
22、provisions of this part of ISO11922. At the time of publication, the edition indicated was valid. All standards are subject to revision, and parties to agreements based on this part of ISO11922are encouraged to investigate the possibility of applying the most recent edition of the standard indicated
23、 below. Members of IEC and ISO maintain registers of currently valid International Standards. ISO 3126:1974, Plastics pipes Measurement of dimensions. 3 Definitions For the purposes of this part of ISO11922, the following definitions apply. 3.1 nominal outside diameter, d n for inch-based series pip
24、e conforming to ISO161-2, the nominal outside diameter serves as a reference outside diameter, expressed in millimetres, to which the permissible deviations are applied as positive and/or negative values 3.2 Outside diameter, d e 3.2.1 mean outside diameter, d em the measured length of the outer cir
25、cumference of the pipe divided by ; 1) , rounded up to the nearest0,1mm 3.2.2 minimum mean outside diameter, d em,min the minimum value of the mean outside diameter specified in the applicable pipe standard. It is equal to the nominal outside diameter d n , expressed in millimetres 3.2.3 maximum mea
26、n outside diameter, d em,max the maximum value of the mean outside diameter specified in the applicable pipe standard 3.2.4 outside diameter at any point, d ey the measured outside diameter through the cross-section at any point of the pipe, rounded up to the nearest0,1mm 3.2.5 out-of-roundness the
27、difference between the measured maximum outside diameter and the measured minimum outside diameter in the same cross-sectional plane of the pipe 3.3 Terms relating to tolerances 2) 3.3.1 tolerance the permissible variation of the specified value of a quantity, expressed as the difference between per
28、missible maximum and minimum values 3.3.2 permissible deviation the difference between a permissible limiting value and a reference value 1) The value for ; is taken to be3,142. 2) These definitions are consistent with ISO 286-12.BSISO 11922-2:1997 2 BSI 09-1999 3.3.3 tolerance grade in a standardiz
29、ed system of limits and fits, a group of tolerances considered as corresponding to the same level of accuracy for all basic sizes 3.4 Wall thickness, e 3.4.1 wall thickness at any point, e y the measured wall thickness at any point around the circumference of the pipe, rounded up to the nearest0,1mm
30、 3.4.2 minimum wall thickness, e y,min the minimum wall thickness for the pipe specified in the applicable pipe standard 3.4.3 maximum wall thickness, e y,max the maximum wall thickness for the pipe specified in the applicable pipe standard 3.4.4 mean wall thickness, e m the arithmetic mean of at le
31、ast four measurements regularly spaced around the same cross-sectional plane of the pipe, including the measured minimum and maximum values obtained, rounded up to the nearest0,1mm NOTEThe minimum number of measurements will be specified in the applicable pipe standard. The actual number of measurem
32、ents will then depend on the fact that the measurement points have to be regularly spaced round the cross-sectional plane and, in addition, have to include both the minimum and the maximum measured values. 4 Tolerances on outside diameters 4.1 Mean outside diameter For pipes conforming to ISO161-2,
33、no relationships are specified or implied between the nominal outside diameter d nand either the minimum outside diameter d e,min(expressed in millimetres) or the maximum outside diameter d e,max(expressed in millimetres) except that d nshall lie within, or at either limit of, the range d e,minto d
34、e,max . The nominal outside diameter specified in ISO161-2therefore serves as a reference mean outside diameter relative to which the permissible deviation may comprise positive (y) and/or negative(z) values. The actual limits on outside diameters for such pipes shall therefore be obtained by choosi
35、ng, fromTable 1 of this part of ISO11922, a tolerance x appropriate to the nominal size, application and material of the pipe, and expressing that tolerance in the formmm relative to the nominal outside diameter as the reference, wherex= y + z. NOTEIn this context, the term “mean outside diameter” i
36、s the arithmetic mean of a series of diameter measurements, and not the central (median) value in a range of permissible diameters. Because d e,minis not directly related to the outside diameter of a pipe as specified in ISO161-2, the values given inTable 1 for tolerance grades F, G and H have been
37、calculated using the same relationship as that used in ISO11922-13 for grades A, B and C, respectively, where the value of the nominal outside diameter, in millimetres, appropriate to the nominal size as specified in ISO161-2, has been used in place of d e,min . Grade F: For all nominal outside diam
38、eters, the tolerance equals0,009d n , rounded up to the nearest0,1mm, with a minimum value of0,3mm and a maximum value of9,2mm. Grade G: For all nominal outside diameters, the tolerance equals0,006d n , rounded up to the nearest0,1mm, with a minimum value of0,3mm and a maximum value of4,0mm. Grade H
39、: For all nominal outside diameters, the tolerance equals0,003d n , rounded up to the nearest0,1mm, with a minimum value of0,3mm and a maximum value of2,0mm. 4.2 Out-of-roundness of outside diameter Three tolerance grades are given inTable 2. The tolerance values for each grade are calculated from t
40、he nominal outside diameter d nspecified in the applicable product standard, all diameters being expressed in millimetres. The calculation factors used are based on practical experience. Grade P is recommended for coiled pipe, subject to an appropriate relaxation treatment being specified in the pro
41、duct standard. Grade P: The tolerance equals0,06d n , rounded up to the nearest0,1mm, and is applicable to nominal outside diameters u 114,3. Grade Q: The tolerance equals0,024d n , rounded up to the nearest0,1mm, with a minimum value of1,0mm. Grade R: a) For nominal outside diameters u 75,3, the to
42、lerance equals (0,008d n+1) mm, rounded up to the nearest0,1mm. b) For nominal outside diameters 75,3 butu 244,5, the tolerance equals0,02d n , rounded up to the nearest0,1mm. c) For nominal outside diameters 244,5, the tolerance equals0,035d n , rounded up to the nearest0,1mm. NOTEThe applicable pi
43、pe standard will specify the point in time at which the out-of-roundness is to be measured, e.g. at the time of extrusion, the time the product leaves the factory or the time of use.y + z BSISO 11922-2:1997 BSI 09-1999 3 Table 1 Tolerances on mean outside diameters Inch-based series Table 2 Toleranc
44、es on out-of-roundness Inch-based series 5 Tolerances on wall thickness 5.1 Wall thickness at any point e y Three tolerance grades are given inTable 3,Table 4 andTable 5 which cover minimum wall thicknesses e y,minup to50mm (Table 3 andTable 4) and46mm (Table 5). The tolerance grade may be specified
45、 in product standards. Tolerances in millimetres Nominal outside diameter Tolerances d n Grade F Grade G Grade H 10,2 13,5 17,2 21,3 0,3 0,3 0,3 0,3 0,3 0,3 0,3 0,3 0,3 0,3 0,3 0,3 26,9 33,7 42,4 48,3 0,3 0,4 0,4 0,5 0,3 0,3 0,3 0,3 0,3 0,3 0,3 0,3 60,3 75,3 88,9 101,6 0,6 0,7 0,8 1,0 0,4 0,5 0,6 0,
46、7 0,3 0,3 0,3 0,4 114,3 140,3 168,3 193,7 1,1 1,3 1,6 1,8 0,7 0,9 1,1 1,2 0,4 0,5 0,5 0,6 219,1 244,5 273 323,9 2,0 2,2 2,5 3,0 1,4 1,5 1,7 2,0 0,7 0,8 0,9 1,0 355,6 406,4 457,2 508 3,2 3,7 4,2 4,6 2,2 2,5 2,8 3,1 1,1 1,2 1,4 1,5 558,2 609,6 660,4 711,2 5,1 5,5 6,0 6,4 3,4 3,7 4,0 4,0 1,7 1,8 1,9 2,
47、0 762 812,8 863,6 914,4 6,9 7,4 7,8 8,3 4,0 4,0 4,0 4,0 2,0 2,0 2,0 2,0 1016 9,2 4,0 2,0 Tolerances in millimetres Nominal outside diameter Tolerances d n Grade P Grade Q Grade R 10,2 13,5 17,2 21,3 0,7 0,9 1,1 1,3 1,0 1,0 1,0 1,0 1,1 1,2 1,2 1,2 26,9 33,7 42,4 48,3 1,7 2,1 2,6 2,9 1,0 1,0 1,1 1,2 1
48、,2 1,3 1,4 1,4 60,3 75,3 88,9 101,6 3,7 4,6 5,4 6,4 1,5 1,9 2,2 2,6 1,5 1,7 1,8 2,2 114,3 140,3 168,3 193,7 6,9 2,8 3,4 4,1 4,7 2,3 2,9 3,4 3,9 219,1 244,5 273 323,9 5,3 5,9 6,6 7,8 4,4 4,9 9,6 11,4 355,6 406,4 457,2 508 8,6 9,8 11,0 12,2 12,5 14,3 16,1 17,8 558,2 609,6 660,4 711,2 13,5 14,7 15,9 17
49、,1 19,6 21,4 23,2 24,9 762 18,3 26,7BSISO 11922-2:1997 4 BSI 09-1999 The tolerance values inTable 3,Table 4 andTable 5 are calculated from the relationships given below, where all values are expressed in millimetres, the relationships being based on practical experience of the extrusion of thermoplastics pipes of wall thickness up to50mm. The tolerance values specified inTable 5 are normally used for pipes which are to be connected by mechanical fittings where it is necessary to have a
