1、BS ISO3601-4:2008ICS 23.100.60; 83.140.50NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAWBRITISH STANDARDFluid power systems O-ringsPart 4: Anti-extrusion rings (back-uprings)This British Standardwas published under theauthority of the StandardsPolicy and StrategyCommittee on 3
2、1 July 2008 BSI 2008ISBN 978 0 580 56330 0Amendments/corrigenda issued since publicationDate CommentsBS ISO 3601-4:2008National forewordThis British Standard is the UK implementation of ISO 3601-4:2008.The UK participation in its preparation was entrusted to TechnicalCommittee MCE/11, Fluid seals an
3、d their housings.A list of organizations represented on this committee can be obtained onrequest to its secretary.This publication does not purport to include all the necessary provisionsof a contract. Users are responsible for its correct application.Compliance with a British Standard cannot confer
4、 immunityfrom legal obligations.BS ISO 3601-4:2008Reference numberISO 3601-4:2008(E)ISO 2008INTERNATIONAL STANDARD ISO3601-4First edition2008-06-01Fluid power systems O-rings Part 4: Anti-extrusion rings (back-up rings) Transmissions hydrauliques et pneumatiques Joints toriques Partie 4: Bagues anti
5、-extrusion BS ISO 3601-4:2008ISO 3601-4:2008(E) PDF disclaimer This PDF file may contain embedded typefaces. In accordance with Adobes licensing policy, this file may be printed or viewed but shall not be edited unless the typefaces which are embedded are licensed to and installed on the computer pe
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8、l Secretariat at the address given below. COPYRIGHT PROTECTED DOCUMENT ISO 2008 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, including photocopying and microfilm, without permission i
9、n 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 Published in Switzerland ii ISO 2008 All rights reservedBS I
10、SO 3601-4:2008ISO 3601-4:2008(E) ISO 2008 All rights reserved iiiContents Page Foreword iv Introduction v 1 Scope 1 2 Normative references 1 3 Terms and definitions .1 4 Symbols 2 5 General requirements related to O-ring housings .2 6 Types of anti-extrusion (back-up) rings 3 6.1 Spiral type, T1 3 6
11、.2 Angle cut type, T25 6.3 Solid type, T35 6.4 Angle cut concave type, T4 6 6.5 Solid concave type, T5 7 7 Positioning of anti-extrusion rings in housings.8 8 Anti-extrusion ring designation code and materials8 8.1 Designation code.8 8.2 Materials .9 9 Dimensions and tolerances 9 9.1 Axial and radia
12、l widths of anti-extrusion rings.9 9.2 Outside diameters of anti-extrusion rings for piston sealing applications.10 9.3 Inside diameters of anti-extrusion rings for rod sealing applications.11 10 Identification statement (reference to this part of ISO 3601) .11 BS ISO 3601-4:2008ISO 3601-4:2008(E) i
13、v ISO 2008 All rights reservedForeword ISO (the International Organization 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 interes
14、ted 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, also take part in the work. ISO collaborates closely with the International Electrotechnical C
15、ommission (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 committees is to prepare International Standards. Draft International Standards adopted by the tech
16、nical 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 possibility that some of the elements of this document may be the subject of patent rights. ISO
17、shall not be held responsible for identifying any or all such patent rights. ISO 3601-4 was prepared by Technical Committee ISO/TC 131, Fluid power systems, Subcommittee SC 7, Sealing devices. ISO 3601 consists of the following parts, under the general title Fluid power systems O-rings: Part 1: Insi
18、de diameters, cross-sections, tolerances and designation codes Part 2: Housing dimensions for general applications Part 3: Quality acceptance criteria Part 4: Anti-extrusion rings (back-up rings) Part 5: Suitability of elastomeric materials for industrial applications BS ISO 3601-4:2008ISO 3601-4:20
19、08(E) ISO 2008 All rights reserved vIntroduction In fluid power systems, power is transmitted and controlled through a fluid (liquid or gas) under pressure within an enclosed circuit. Where high pressures are encountered, it is recommended that an anti-extrusion ring (back-up ring) be incorporated w
20、ithin the O-ring housing to limit extrusion of the O-ring between the metal parts (e.g. cylinder bore and piston or rod and housing). BS ISO 3601-4:2008BS ISO 3601-4:2008INTERNATIONAL STANDARD ISO 3601-4:2008(E) ISO 2008 All rights reserved 1Fluid power systems O-rings Part 4: Anti-extrusion rings (
21、back-up rings) 1 Scope This part of ISO 3601 specifies dimensions and tolerances for five types of anti-extrusion rings, which are also known as back-up rings: a) spiral type (T1); b) angle cut type (T2); c) solid type (T3); d) angle cut concave type (T4); e) solid concave type (T5). These anti-extr
22、usion rings are for use with selected O-ring sizes as specified in ISO 3601-1 and the relevant housing dimensions specified in ISO 3601-2. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited ap
23、plies. For undated references, the latest edition of the referenced document (including any amendments) applies. ISO 3601-11), Fluid power systems O-rings Part 1: Inside diameters, cross-sections, tolerances and designation codes ISO 3601-2:2008, Fluid power systems O-rings Part 2: Housing dimension
24、s for general applications ISO 5598, Fluid power systems and components Vocabulary 3 Terms and definitions For the purposes of this document, the terms and definitions given in ISO 5598 apply. 1) To be published. (Revision of ISO 3601-1:2002) BS ISO 3601-4:2008ISO 3601-4:2008(E) 2 ISO 2008 All right
25、s reserved4 Symbols The following letter symbols are used in this part of ISO 3601: b1width of O-ring housing without anti-extrusion ring b2width of O-ring housing with one anti-extrusion ring b3width of O-ring housing with two anti-extrusion rings b5width of single anti-extrusion ring, angle cut ty
26、pes T2 and T4, and solid types T3 and T5 b6width of anti-extrusion ring, spiral type T1 b7total width (b5+ h) at apex of single anti-extrusion ring, angle cut concave type T4 and solid concave type T5 d2O-ring cross-section diameter d3housing diameter for piston seal housings d4bore diameter for pis
27、ton application d5rod diameter d6housing diameter for rod seal housings d9piston diameter d10bore diameter for rod application d14internal diameter of anti-extrusion ring (spiral type T1 only) d15external diameter of anti-extrusion ring (spiral type T1 only) d16inside diameter of anti-extrusion ring
28、 (angle cut types T2 and T4, or solid types T3 and T5) d17outside diameter of anti-extrusion ring (angle cut types T2 and T4, or solid types T3 and T5) h extension of concave anti-extrusion ring beyond b5base width l gap of anti-extrusion ring, spiral type T1, on mandrel diameter d14R radius of cavi
29、ty in concave anti-extrusion ring t radial section of anti-extrusion ring 5 General requirements related to O-ring housings For general requirements of O-ring housings, such as surface roughness, corners and edges of undefined shape, lead-in chamfers, housing diameter tolerances and housing widths,
30、see the related clauses in ISO 3601-2. BS ISO 3601-4:2008ISO 3601-4:2008(E) ISO 2008 All rights reserved 36 Types of anti-extrusion (back-up) rings 6.1 Spiral type, T1 6.1.1 The spiral type, T1, anti-extrusion ring (see Figure 1) is typically associated with applications in which the system pressure
31、 is between 10 MPa (100 bar) and 20 MPa (200 bar). Continuous rings, such as the angle cut type (T2) or the solid type (T3), are preferred for use at pressures higher than 20 MPa (200 bar), but assembly problems can be encountered with closed housings or at small diameters. aThis angle may be increa
32、sed to 45 5 when d14is less than 7,0 mm. NOTE Direction of the spiral is optional. Figure 1 Spiral type (T1) anti-extrusion ring 6.1.2 At higher temperatures, typically in excess of 100 C, anti-extrusion rings can be necessary even when pressures are less than 10 MPa (100 bar). Independent of temper
33、ature and pressure, special operating conditions can also require the use of anti-extrusion rings. These operating conditions should be discussed with the seal supplier at the design stage. BS ISO 3601-4:2008ISO 3601-4:2008(E) 4 ISO 2008 All rights reserved6.1.3 Dimensions shall conform to the requi
34、rements given in Table 1. Table 1 Dimensions of gap, l, of spiral type (T1) anti-extrusion rings in relation to mandrel diameter, d14Dimensions in millimetresO-ring nominal cross-section d2Mandrel diameter d14Gap l d14u 10 1,2 0,4 10 60 3 1,5 d14u 20 1,2 0,4 20 170 4,4 2 d14u 19 1,2 0,4 19 393 6,4 2
35、 d14u 26 1,8 0,6 26 280 6,4 2 6,99 d14 100 6,4 2 BS ISO 3601-4:2008ISO 3601-4:2008(E) ISO 2008 All rights reserved 56.2 Angle cut type, T2 The angle cut type, T2, anti-extrusion ring (see Figure 2) is the most widely used, mainly because it is easier to install than the solid type, T3, and affords b
36、etter protection of the O-ring when the system pressure ranges from 15 MPa (150 bar) to greater than 20 MPa (200 bar). Dimensions in millimetres unless otherwise indicated aThis angle may be increased to 45 5 when d16is less than 10,0 mm. NOTE Direction of the angle cut is optional. Figure 2 Angle c
37、ut type (T2) anti-extrusion ring 6.3 Solid type, T3 The solid type, T3, anti-extrusion ring (see Figure 3), while difficult to install in O-ring housings that have small diameters or are closed, affords the ultimate protection of the O-ring at all pressures and temperatures. It is the preferred type
38、 for system pressures greater than 25 MPa (250 bar) and temperatures higher than 135 C. Dimensions in millimetres Figure 3 Solid type (T3) anti-extrusion ring BS ISO 3601-4:2008ISO 3601-4:2008(E) 6 ISO 2008 All rights reserved6.4 Angle cut concave type, T4 The angle cut concave type, T4, anti-extrus
39、ion ring (see Figure 4) is similar to the angle cut type, T2, but is designed to accommodate the O-ring and retain its shape better under high pressure. CAUTION This type of anti-extrusion ring is not recommended for automatic assembly. Dimensions in millimetres aAngle is normally 30 5 but may be in
40、creased to 45 5 when d16is less than 10,0 mm. bThis area shall be free of burrs. cThe O-ring is always positioned against the concave side of the anti-extrusion ring. NOTE Direction of the angle cut is optional. Figure 4 Angle cut concave type (T4) anti-extrusion ring BS ISO 3601-4:2008ISO 3601-4:20
41、08(E) ISO 2008 All rights reserved 76.5 Solid concave type, T5 The solid concave type, T5, anti-extrusion ring (see Figure 5) is similar to the solid type, T3, but is designed to accommodate the O-ring and retain its shape better under high pressure. CAUTION This type of anti-extrusion ring is not r
42、ecommended for automatic assembly. Dimensions in millimetres aThis area shall be free of burrs. bThe O-ring is always positioned against the concave side of the anti-extrusion ring. Figure 5 Solid concave type (T5) anti-extrusion ring BS ISO 3601-4:2008ISO 3601-4:2008(E) 8 ISO 2008 All rights reserv
43、ed7 Positioning of anti-extrusion rings in housings Positioning of anti-extrusion rings depends on the application and the direction in which pressure acts on the O-ring housing. Anti-extrusion rings shall be positioned in accordance with Figures 6 and 7. a) Without anti-extrusion rings b) With one
44、anti-extrusion ring c) With two anti-extrusion rings aPressure acting in one direction. bPressure acting in alternating directions. Figure 6 Positioning of anti-extrusion rings in a piston sealing application a) Without anti-extrusion rings b) With one anti-extrusion ring c) With two anti-extrusion
45、rings aPressure acting in one direction. bPressure acting in alternating directions. Figure 7 Positioning of anti-extrusion rings in a rod sealing application 8 Anti-extrusion ring designation code and materials 8.1 Designation code Anti-extrusion rings that conform to this part of ISO 3601 can be d
46、esignated by either a custom designation agreed between the user and manufacturer or the designation code described as follows: a) the words “Anti-extrusion ring” followed by a space; b) “ISO 3601-4” followed by a hyphen; c) the type of anti-extrusion ring (T1 for spiral type; T2 for angle cut type;
47、 T3 for solid type; T4 for angle cut concave type; or T5 for solid concave type), followed by a hyphen; BS ISO 3601-4:2008ISO 3601-4:2008(E) ISO 2008 All rights reserved 9d) three digits to indicate the cross-section, d2, of the O-ring in millimetres (for example, if d2= 6,99 mm, the three digits wo
48、uld be 699), followed by a hyphen; e) the application type, that is, PD for piston dynamic, PS for piston static, RD for rod dynamic, or RS for rod static, followed by a hyphen; f) six digits to indicate the anti-extrusion rings working diameter in millimetres, that is, the inside diameter (d14or d1
49、6) for rod applications or the outside diameter (d15or d17) for piston applications (for example, a working diameter of 200,00 mm would be designated as 020000), followed by a hyphen; g) six digits to indicate the housing diameter, d3, for piston seal housings or d6for rod seal housings, in millimetres (for example, a housing diameter of 211,8 mm would be designated as 021180). EXAMPLE An anti-extrusion ring of the spiral type for use w
