1、August 2010 Translation by DIN-Sprachendienst.English price group 10No part of this translation may be reproduced without prior permission ofDIN Deutsches Institut fr Normung e. V., Berlin. Beuth Verlag GmbH, 10772 Berlin, Germany,has the exclusive right of sale for German Standards (DIN-Normen).ICS
2、 23.100.60!$jB7“1713120www.din.deDDIN ISO 3601-4Fluid power systems O-rings Part 4: Anti-extrusion rings (back-up rings) (ISO 3601-4:2008)English translation of DIN ISO 3601-4:2010-08Fluidtechnik O-Ringe Teil 4: Sttzringe (ISO 3601-4:2008)Englische bersetzung von DIN ISO 3601-4:2010-08Transmissions
3、hydrauliques et pneumatiques Joints toriques Partie 4: Bagues anti-extrusion (ISO 3601-4:2008)Traduction anglaise de DIN ISO 3601-4:2010-08www.beuth.deIn case of doubt, the German-language original shall be considered authoritative.Document comprises 15 pages08.10 DIN ISO 3601-4:2010-08 A comma is u
4、sed as the decimal marker. Contents Page National foreword .3 Introduction .4 1 Scope 5 2 Normative references 5 3 Terms and definitions5 4 Symbols 6 5 General requirements related to O-ring housings6 6 Types of anti-extrusion (back-up) rings 7 6.1 Spiral type, T1 7 6.2 Angle cut type, T2 9 6.3 Soli
5、d type, T39 6.4 Angle cut concave type, T4.10 6.5 Solid concave type, T5 11 7 Positioning of anti-extrusion rings in housings.12 8 Anti-extrusion ring designation code and materials12 8.1 Designation code.12 8.2 Materials .13 9 Dimensions and tolerances 13 9.1 Axial and radial widths of anti-extrusi
6、on rings.13 9.2 Outside diameters of anti-extrusion rings for piston sealing applications .14 9.3 Inside diameters of anti-extrusion rings for rod sealing applications .15 10 Identification statement (reference to this part of ISO 3601)15 2 Start of validity This standard takes effect on 1 August 20
7、10. National foreword This standard has been prepared by Technical Committee ISO/TC 131 “Fluid power systems”, Subcommittee SC 7 “Sealing devices”, Working Group WG 3 “Fluid power systems and components Sealing devices The responsible German body involved in its preparation was the Normenausschuss M
8、aschinenbau (Mechanical Engineering Standards Committee), Working Committee NA 060-36-73 AA O-Ringe of section Fluidtechnik. International Standards referred to in this standard have been published as the corresponding DIN ISO or DIN EN ISO Standards with the same number. For ISO 5598, there is no n
9、ational standard available. 3 DIN ISO 3601-4:2010-08 Design criteria for standard O-ring applications”. Introduction 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 reco
10、mmended that an anti-extrusion ring (back-up ring) be incorporated within 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). Fluid power systems O-Rings Part 4: Anti-extrusion rings (back-up rings) 4 DIN ISO 3601-4:2010-08
11、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-extrusion rings are
12、 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 applies. For unda
13、ted 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 dimensions for general a
14、pplications 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) 5 DIN ISO 3601-4:2010-08 4 Symbols The following letter symbols are used
15、 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 types T2 and T4, and solid types T3 and T5 b6width of anti-
16、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 piston application d5rod diameter d6housing diameter for rod
17、 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 (angle cut types T2 and T4, or solid types T3 and T5) d1
18、7outside 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 cavity in concave anti-extrusion ring t radial section of ant
19、i-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, see the related clauses in ISO 3601-2. 6 DIN ISO 3601-4:2
20、010-08 6 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 is between 10 MPa (100 bar) and 20 MPa (200 bar). Continuous rings, such as the angle cut type (T2
21、) 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 increased to 45 5 when d14is less than 7,0 mm. NOTE Direction of the spiral is optional. Figure 1 Spiral
22、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 temperature and pressure, special operating conditions can also require the use of anti-extrusion rings.
23、These operating conditions should be discussed with the seal supplier at the design stage. 7 DIN ISO 3601-4:2010-08 6.1.3 Dimensions shall conform to the requirements given in Table 1. Table 1 Dimensions of gap, l, of spiral type (T1) anti-extrusion rings in relation to mandrel diameter, d14Dimensio
24、ns 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 d14u 26 1,8 0,6 26 280 6,4 2 6,99 d14 100 6,4 2 8 DIN ISO 3601-4:2010-08 6.2 Angle cut type, T2 The angle cut type, T2, anti-extrusion ring
25、(see Figure 2) is the most widely used, mainly because it is easier to install than the solid type, T3, and affords better 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
26、 may be increased to 45 5 when d16is less than 10,0 mm. NOTE Direction of the angle cut is optional. Figure 2 Angle cut 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
27、are closed, affords the ultimate protection of the O-ring at all pressures and temperatures. It is the preferred type 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 9 DIN ISO 3601-4:2010-08
28、 6.4 Angle cut concave type, T4 The angle cut concave type, T4, anti-extrusion 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 automati
29、c assembly. Dimensions in millimetres aAngle is normally 30 5 but may be increased 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 Angl
30、e cut concave type (T4) anti-extrusion ring 10 DIN ISO 3601-4:2010-08 6.5 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 ty
31、pe of anti-extrusion ring is not recommended 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 11 DIN ISO 3601-4:2010-08 7 Pos
32、itioning 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 anti-ex
33、trusion 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 rings a
34、Pressure 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 designat
35、ed 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; T3 for
36、 solid type; T4 for angle cut concave type; or T5 for solid concave type), followed by a hyphen; 12 DIN ISO 3601-4:2010-08 d) three digits to indicate the cross-section, d2, of the O-ring in millimetres (for example, if d2= 6,99 mm, the three digits would be 699), followed by a hyphen; e) the applic
37、ation 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 d16) for rod applications or the outside diameter
38、(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
39、 would be designated as 021180). EXAMPLE An anti-extrusion ring of the spiral type for use with an O-ring with a cross-section of 6,99 mm, in a rod dynamic application with a working diameter of 200,00 mm for use in a housing of diameter 211,8 mm would be designated as Anti-extrusion ring ISO 3601-4
40、-T1-699-RD-020000-021180 8.2 Materials 8.2.1 The most popular material for anti-extrusion rings is unfilled polytetrafluoroethylene (PTFE). Because this material is very soft compared to other plastics, it closes the extrusion gap under pressure and protects the O-ring against extrusion into the gap
41、 between the metal parts. For some applications, a portion of other materials may be added to the PTFE for additional strength. These materials are mainly glass (typically 15 % of the material mass), carbon (typically 10 % to 15 %) or bronze (typically 40 % to 60 %). Other filler materials may be us
42、ed. 8.2.2 Polyamide (PA) material, both unfilled (virgin) and filled, is also used for anti-extrusion rings. This material shows good properties for this type of application under some operating conditions. 8.2.3 Other materials, such as hard block/soft block thermoplastics and polyurethane, may als
43、o be used as long as they serve the purpose of preventing the O-ring from extruding into the gap between the metal parts under operating conditions. Users should consult the supplier for recommendations for the most suitable material that satisfies their individual requirements in specific applicati
44、ons. 9 Dimensions and tolerances 9.1 Axial and radial widths of anti-extrusion rings 9.1.1 Axial widths Dimensions and tolerances for axial widths b5or b6of anti-extrusion rings, in relation to the cross-sections of the O-rings with which they are to be used, shall be in accordance with Table 2. The
45、 concave anti-extrusion rings have not only an axial width, b5, but also other dimensions that define their geometry;these dimensions and their appropriate tolerances shall be in accordance with Table 2. 13 DIN ISO 3601-4:2010-08 Table 2 Dimensions and tolerances for anti-extrusion rings for ISO 360
46、1-1 O-rings Dimensions in millimetres O-ring cross-section d2Anti-extrusion ring dimensions 1,78 2,62 3,53 5,33 6,99 b5, b61,4 0,1 1,4 0,1 1,4 0,1 1,8 0,1 2,6 0,1 b71,7 0,1 1,8 0,1 2,0 0,1 2,8 0,1 4,1 0,1 h 0,3 0,4 0,6 1,1 1,6 R 1,2 1,6 2,0 3,0 4,0 9.1.2 Radial widths 9.1.2.1 General The radial widt
47、hs of anti-extrusion rings depend on the radial depths of the housings, and these depend on the application, for example dynamic hydraulic or static hydraulic. For normal pneumatic applications, it is not necessary to use anti-extrusion rings with O-rings. 9.1.2.2 Piston sealing For piston sealing,
48、the radial depths of the housings shall be calculated by subtracting the nominal values of the piston housing diameter, d3, from the bore diameter, d4. Values for these dimensions are given in ISO 3601-2:2008, Tables 2 and 3. 9.1.2.3 Rod sealing For rod sealing, the radial depth of the housings shal
49、l be calculated by subtracting the nominal values of the rod diameter, d5, from the rod housing diameter, d6. Values for these dimensions are given in ISO 3601-2:2008, Tables 4 and 5. 9.1.2.4 Tolerance The tolerance for the radial width, t, of the anti-extrusion rings shall be 00,1mm.9.2 Outside diameters of anti-extrusion rings for piston sealing applications 9.2.1 General For anti-extrusion rings used in piston sealing applications, the outside diameters d15and d17shall be taken