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1、| | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | BRITISH STANDARD BS EN 1337-7:2001 The Eur
2、opean Standard EN 1337-7:2000 has the status of a British Standard ICS 91.010.30; 93.040 NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAW Structural bearings Part 7: Spherical and cylindrical PTFE bearings This British Standard, having been prepared under the direction of the S
3、ector Committee for Building and Civil Engineering, was published under the authority of the Standards Committee and comes into effect on 15 February 2001 BSI 02-2001 ISBN 0 580 36965 X BS EN 1337-7:2001 Amendments issued since publication Amd. No.DateComments National foreword This British Standard
4、 is the official English language version of EN 1337-7:2000. The UK participation in its preparation was entrusted to Technical Committee B/522, Structural bearings, which has the responsibility to: aid enquirers to understand the text; present to the responsible European committee any enquiries on
5、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 organizations represented on this committee can be obtained on request to its secretary. Cross-references The British Stan
6、dards 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 Correspondence Index, or by using the Find facility of the BSI Standards Electronic Catalogue. A British Standard d
7、oes 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 not of itself confer immunity from legal obligations. Summary of pages This document comprises a front cover, an in
8、side front cover, the EN title page, pages 2 to 26, an inside back cover and a back cover. The BSI copyright notice displayed in this document indicates when the document was last issued. EUROPEAN STANDARD NORME EUROPENNE EUROPISCHE NORM EN 1337-7 December 2000 ICS 91.010.30 English version Structur
9、al bearings - Part 7: Spherical and cylindrical PTFE bearings Appareils dappui structuraux - Partie 7: Appareils dappui cylindriques et sphriques comportant du PTFE Lager im Bauwesen - Teil 7: Kalotten- und Zylinderlager mit PTFE This European Standard was approved by CEN on 18 November 2000. CEN me
10、mbers are bound to comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration. Up-to-date lists and bibliographical references concerning such national standards may be obtained on applica
11、tion to the Management Centre or to any CEN member. This European Standard exists in three official versions (English, French, German). A version in any other language made by translation under the responsibility of a CEN member into its own language and notified to the Management Centre has the sam
12、e status as the official versions. CEN members are the national standards bodies of Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom. EUROPEAN COMMITTEE FOR S
13、TANDARDIZATION COMIT EUROPEN DE NORMALISATION EUROPISCHES KOMITEE FR NORMUNG Management Centre: rue de Stassart, 36 B-1050 Brussels 2000 CENAll rights of exploitation in any form and by any means reserved worldwide for CEN national Members. Ref. No. EN 1337-7:2000 E Page 2 EN 1337-7:2000 Contents Fo
14、reword3 Introduction4 1Scope5 2Normative references5 3Terms and definitions, symbols and abbreviations5 4Functional requirements10 5Material properties10 6Design requirements10 7Manufacturing, assembly and tolerances13 8Conformity evaluation13 Annex A (informative) Method for calculating the eccentr
15、icities in spherical and cylindrical PTFE bearings14 Annex B (informative) Reduced area for curved sliding surfaces16 Annex ZA (informative) Provisions for the CE marking of cylindrical and spherical PTFE bearings (with or without flat sliding elements) under the EU Construction Products Directive19
16、 Page 3 EN 1337-7:2000 Foreword This European Standard has been prepared by Technical Committee CEN/TC 167 “Structural bearings“, the secretariat of which is held by UNI. This European Standard shall be given the status of a national standard, either by publication of an identical text or by endorse
17、ment, at the latest by June 2001, and conflicting national standards shall be withdrawn at the latest by June 2001. This European Standard EN 1337 “ Structural bearings” , consists of the following 11 Parts: Part 1: General design rules Part 2: Sliding elements Part 3: Elastomeric bearings Part 4: R
18、oller bearings Part 5: Pot bearings Part 6: Rocker bearings Part 7: Spherical and cylindrical PTFE bearings Part 8: Guide bearings and restrain bearings Part 9: Protection Part 10: Inspection and maintenance Part 11: Transport, storage and installation Further to CEN/TC 167 s decision Part 1 and 2 f
19、orm a package of standards and they come into force together, while the other parts come into force separately after the publication of Parts 1 and 2. Annexes A, B and ZA are informative. According to the CEN/CENELEC Internal Regulations, the national standards organizations of the following countri
20、es are bound to implement this European Standard: Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and the United Kingdom. Page 4 EN 1337-7:2000 Introduction This standard consi
21、ders a minimum operating temperature of 35C. An extension down to 40C will be considered in a future amendment. Applications beyond the range of temperature given in clause 1 need special consideration not covered by this standard. Characteristics, requirements and test procedures given in this stan
22、dard do not apply in such cases. Page 5 EN 1337-7:2000 1Scope This European Standard deals with the requirements for the design and manufacture of spherical and cylindrical PTFE bearings. The requirements and properties of the curved sliding surfaces are included in EN 1337-2:2000. Spherical and cyl
23、indrical bearings with an included angle 2 ? 60 and 2 ? 75 respectively are beyond the scope of this European Standard. (see Figure 6). For the purpose of controlling the degree of freedom the bearings may be combined with flat sliding elements and guides according to EN 1337-2:2000 and restraining
24、rings as per 6.3.4. Cylindrical bearings are susceptible to unexpected moments about the transverse axis of the cylindrical surface. Additional limitation of application to be taken into consideration is given in clause 1 of EN 1337-2:2000. 2Normative references This European Standard incorporates,
25、by dated or undated reference, provisions from other publications. These normative references are cited at the appropriate places in the text and the publications are listed hereafter. For dated references, subsequent amendments to or revisions of any of these publications apply to this European Sta
26、ndard only when incorporated in it by amendment or revision. For undated references the latest edition of the publication referred to applies (including amendments). EN 1337-1:2000Structural bearings - Part 1: General design rules EN 13372:2000Structural bearings - Part 2: Sliding elements prEN 1337
27、5:1996Structural bearings - Part 5: Pot bearings 3Terms and definitions, symbols and abbreviations 3.1 Terms and definitions For the purposes of this European Standard, the following terms and definitions apply. 3.1.1 backing plate metallic component which supports sliding materials. 3.1.2 cylindric
28、al PTFE bearing bearing consisting of a backing plate with a convex cylindrical surface (rotational element) and a backing plate with a concave cylindrical surface between which a PTFE sheet and the mating material form a curved sliding surface (see Figure 1). Cylindrical PTFE bearings are also used
29、 in combination with flat sliding elements and guides to form free or guided bearings (see Figure 2). NOTENumbers in brackets in Figures 1 and 2 refer to the examples shown in Figure 1 of EN 1337- 1:2000. Page 6 EN 1337-7:2000 a) fixed by end stops and sliding surface (7.1) b) without end stops for
30、displacements in y direction (7.2) Figure 1 - Cylindrical PTFE bearings a) free for displacements in any direction (7.4)b) guided by an internal guide for displacements in x direction (7.3) c) guided by external guides for displacements in x direction Figure 2 - Cylindrical PTFE bearings combined wi
31、th flat sliding elements Page 7 EN 1337-7:2000 3.1.3 guide sliding element which restrains a sliding bearing from moving in one axis. 3.1.4 lubricant special grease used to reduce the friction and wear in the sliding surfaces. 3.1.5 mating surface hard smooth metallic surface against which the PTFE
32、slides. 3.1.6 polytetrafluoroethylene (PTFE) a thermoplastic material used for its low coefficient of friction. 3.1.7 sliding materials materials which form sliding surfaces. 3.1.8 sliding surface combination of a pair of flat or curved surfaces of different materials which allow relative displaceme
33、nts. 3.1.9 spherical PTFE bearing bearing consisting of a backing plate with a convex spherical surface (rotational element) and a backing plate with a concave spherical surface between which a PTFE sheet and the mating material form a curved sliding surface (see Figure 3). Spherical PTFE bearings a
34、re also used in combination with flat sliding elements and guides to form free and guided bearings (see Figures 4 a) to 4 c). Spherical PTFE bearings combined with a flat sliding element can be used together with a restraining ring to form fixed bearings (see Figure 4 d). NOTENumbers in brackets in
35、Figures 3 and 4 refer to the examples shown in Figure 1 of EN 1337- 1:2000. NOTE Fixed by sliding surface (3.2). Figure 3 - Spherical PTFE bearing Page 8 EN 1337-7:2000 a) free for displacements in any direction (3.5) b) guided by an internal guide for displacements in one direction (3.4) c) guided
36、by external guides for displacements in one direction (3.3)d) fixed by a restraining ring (3.1) Figure 4 - Spherical PTFE bearings combined with flat sliding elements 3.2 Symbols The most frequently occurring symbols are defined below. Those that are local, and unique to a particular clause, are def
37、ined at their first appearance. 3.2.1Latin upper case letters Acontact area of sliding surface; projected area of the curved sliding surfacemm2 Ldiameter or diagonal of the projected area of the PTFE sheet .mm Page 9 EN 1337-7:2000 Figure 5 - Plan dimensions of spherical and cylindrical bearings Nax
38、ial or normal force N; kN Vlateral or shear force . N; kN 3.2.2Latin lower case letters aside of the projection in plan of rectangular PTFE surfaces . mm bas before; distance from the projected area of the curved sliding surface . mm cdimension mm ddiameter . mm eeccentricity . mm fnominal compressi
39、ve strength . N/mm2 hprotrusion of PTFE sheet from its recess . mm rradius of curvature mm tthickness mm xlongitudinal axis ytransverse axis zaxis normal to the principal bearing surface 3.2.3Greek letters ?rotation angle.radians ?deviation angle from vertical axis of the line of action of the appli
40、ed load.degrees, radians ?zmaximum deviation of plane or curved sliding surfaces from theoretical surface mm ?half included angle of PTFE curved surfaces .degrees, radians ?ratio, coefficient ?coefficient of friction ?normal pressure .N/mm2 Page 10 EN 1337-7:2000 3.2.4Subscripts bbacking plate ddesi
41、gn value minminimum pPTFE Sinternal forces and moments from actions ttotal 3.3 Abbreviations PTFEPolytetrafluoroethylene 4Functional requirements 4.1 General Cylindrical PTFE bearings shall permit rotational movements about one axis, spherical PTFE bearings about any axis. They shall be capable of t
42、ransferring specified forces between superstructure and substructure. 4.2 Functional requirements for coefficient of friction The sliding surfaces shall meet the functional requirements given in 4.1 of EN 1337-2:2000. 4.3 Functional requirements for load bearing capacity The sliding surfaces shall m
43、eet the functional requirements given in 6.8.3 and 6.9 of EN 1337-2:2000. 4.4 Functional requirements for rotation capability The sliding surfaces shall meet the functional requirements given in clause 4 of EN 1337-2:2000. 5Material properties The materials to be used and the properties to be verifi
44、ed shall be in accordance with clause 5 of EN 1337-2:2000. 6Design requirements NOTE This clause gives requirements for the design of components which are specific to spherical and cylindrical bearings and which are in addition to those given in clause 6 of EN 1337-2:2000. 6.1 Design principles For
45、design calculations the principles given in clause 5 of EN 1337-1:2000 shall be taken into account. NOTE The design values of internal forces and moments as well as of movements should be available from a bearing schedule as shown in annex B of EN 1337-1:2000. 6.2 Design verification for curved slid
46、ing surfaces 6.2.1General For the purpose of verifications as per 6.2.2 and 6.2.3 the curved sliding surface shall be replaced by its projection on a plane surface as shown in Figure 6. Page 11 EN 1337-7:2000 Key 1 Projected area Figure 6 - Verification scheme for the curved sliding surface (example
47、) Internal forces and moments acting on the curved sliding surface due to frictional resistance, externally applied horizontal loads and the rotated condition of the bearing shall be taken into account when determining the resulting total eccentricity etof the axial force NS. Secondary effects due t
48、o the action of the restraints shall also be considered. NOTE In annex A of this standard, formulae are given for the evaluation of the eccentricities in the most common cases. The frictional resistance shall be determined using the design coefficients of friction given in Table 11 of EN 1337-2:2000
49、. 6.2.2 Separation of sliding surfaces NOTE Separation of the sliding surfaces may lead to wear due to contamination and increased deformation due to lack of confinement. As this could endanger long term fitness for use, the condition ?p = 0 is considered as serviceability limit state. It shall be verified that ?p? 0 in all load combinations at serviceability limit state. In doing so the sliding material shall be assumed to be linear elastic and the backing plates shall be deemed to be rigid. The condition ?p? 0 is satisfied at serviceability limit state wh