1、BRITISH STANDARD BS ISO 8434-3:2005 Metallic tube connections for fluid power and general use Part 3: O-ring face seal connectors ICS 23.100.40 BS ISO 8434-3:2005 This British Standard was published under the authority of the Standards Policy and Strategy Committee on 2 September 2005 BSI 2 Septembe
2、r 2005 ISBN 0 580 46414 8 National foreword This British Standard reproduces verbatim ISO 8434-3:2005 and implements it as the UK national standard. It supersedes BS ISO 8434-3:1995 which is withdrawn. The UK participation in its preparation was entrusted by Technical Committee MCE/18, Fluid power s
3、ystems, to Subcommittee MCE/18/-/4, Connectors, which has the responsibility to: A list of organizations represented on this subcommittee can be obtained on request to its secretary. Cross-references The British Standards which implement international publications referred to in this document may be
4、 found in the BSI Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Search” facility of the BSI Electronic Catalogue or of British Standards Online. This publication does not purport to include all the necessary provisions of a contract. Users are
5、responsible for its correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. aid enquirers to understand the text; present to the responsible international/European committee any enquiries on the interpretation, or proposals for change, and k
6、eep UK interests informed; monitor related international and European developments and promulgate them in the UK. Summary of pages This document comprises a front cover, an inside front cover, the ISO title page, pages ii to vi, pages 1 to 63 and a back cover. The BSI copyright notice displayed in t
7、his document indicates when the document was last issued. Amendments issued since publication Amd. No. Date Comments Reference number ISO 8434-3:2005(E)INTERNATIONAL STANDARD ISO 8434-3 Second edition 2005-07-15 Metallic tube connections for fluid power and general use Part 3: O-ring face seal conne
8、ctors Raccordements de tubes mtalliques pour transmissions hydrauliques et pneumatiques et applications gnrales Partie 3: Connecteurs joints faciaux toriques BS ISO 8434-3:2005ii iii Contents Page Foreword. v Introduction . vi 1 Scope . 1 2 Normative references . 1 3 Terms and definitions. 2 4 Mater
9、ials 3 4.1 General. 3 4.2 Connector bodies . 3 4.3 Nuts 3 4.4 O-rings . 4 5 Pressure/temperature requirements. 4 6 Designation of connectors 5 7 Requirements for tubes 7 8 Across-flats dimensions and tolerances 8 9 Design 8 9.1 Connectors 8 9.2 Dimensions 8 9.3 Passage tolerances 8 9.4 Angular toler
10、ances . 8 9.5 Contour details 8 9.6 Stud ends. 8 9.7 Reducing connectors . 8 10 Screw threads . 8 10.1 O-ring face seal ends 8 10.2 Stud ends (connection ends) 9 11 Manufacture. 9 11.1 Construction 9 11.2 Workmanship 9 11.3 Finish 9 11.4 Connector protection . 9 11.5 Corners 9 12 Assembly instructio
11、n . 10 13 Procurement information. 10 14 Marking of components . 10 15 Performance and qualification test. 10 15.1 Performance requirements 10 15.2 Test data form . 12 16 Identification statement (reference to this part of ISO 8434) . 12 Annex A (normative) Specification for 1-14 UNS inch screw thre
12、ads Basic dimensions 45 Annex B (normative) Reduction factors for reducing connectors 46 Annex C (normative) Formed tube connection for ISO 8434-3 O-ring face seal connectors. 56 BS ISO 8434-3:2005iv Annex D (informative) O-ring face seal tube and hose connections with metric or inch tubing or swive
13、l hose connector 58 Annex E (informative) Typical connections with O-ring face seal connectors 59 Annex F (informative) Assembly instructions for adjustable connectors in ISO 6149-1 ports 62 BS ISO 8434-3:2005v Foreword ISO (the International Organization for Standardization) is a worldwide federati
14、on 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 established has the right to be represented on that committee
15、. 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 standardization. International Standards are drafted in accordance w
16、ith 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 technical committees are circulated to the member bodies for voting. Publication as an International Standard requires appr
17、oval 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 shall not be held responsible for identifying any or all such patent rights. ISO 8434-3 was prepared by Technical Commi
18、ttee ISO/TC 131, Fluid power systems, Subcommittee SC 4, Connectors and similar products and components. This second edition cancels and replaces the first edition (ISO 8434-3:1995), which has been technically revised. ISO 8434 consists of the following parts, under the general title Metallic tube c
19、onnections for fluid power and general use: Part 1: 24 cone connectors Part 2: 37 flared fittings Part 3: O-ring face seal connectors Part 4: 24 cone connectors with O-ring weld-on nipples 1) Part 5: Test methods for threaded hydraulic fluid power connections 2) Part 6: 60 cone connectors with or wi
20、thout O-ring 1) ISO 8434-4 will be incorporated into the revision of ISO 8434-1. 2) ISO 8434-5 will be withdrawn once ISO 19879 is published. BS ISO 8434-3:2005vi Introduction In fluid power systems, power is transmitted and controlled through a fluid (liquid or gas) under pressure within an enclose
21、d circuit. In general applications, a fluid may be conveyed under pressure. Components may be connected through their ports by connections (connectors) and conductors (tubes and hoses). Tubes are rigid conductors; hoses are flexible conductors. This part of ISO 8434 is based on the USA standard ANSI
22、/SAE J1453. The threads for the O-ring face seal connection are unified inch threads to ISO 263. The inch threads were not changed to metric threads to ISO 261 to allow connectors complying with this standard to be used in existing applications without requiring a change to tube or hose assemblies.
23、Also, the thread-to-nut overtorque and seal performance have been extensively tested; to change to metric threads would require an extensive test program at considerable cost without providing any functional improvement. The threads are integral to themselves, connectors of this type match only to t
24、hemselves, and other than having metric threads, no value in changing could be found. Major international companies that have used these connectors have adopted the design without noting any problems. All wrench flats are dimensioned to be used with ISO standard metric wrenches. BS ISO 8434-3:20051
25、Metallic tube connections for fluid power and general use Part 3: O-ring face seal connectors 1 Scope This part of ISO 8434 specifies the general and dimensional requirements for the design and performance of O-ring face seal connectors made of steel for tube outside diameters or hose inside diamete
26、rs of 6 mm through 38 mm, inclusive. These connectors are for use in fluid power and general applications where elastomeric seals can be used to prevent fluid leakage, including leakage caused by variations in assembly procedures. They are intended for the connection of tubes and hose fittings to po
27、rts in accordance with ISO 6149-1. (See ISO 12151-1 for related hose fitting specification.) These connectors provide leakproof, full-flow connections in hydraulic systems operating from a vacuum of 6,5 kPa 0,065 bar 3) absolute pressure to the working pressures shown in Table 1. Because many factor
28、s influence the pressure at which a system performs satisfactorily, these values shall not be understood as guaranteed minimums. For every application, it is recommended that sufficient testing be conducted and reviewed by both the user and manufacturer to ensure that required performance levels are
29、 met. NOTE For use under conditions outside the pressure and/or temperature limits specified, see 5.3. Both metric and inch tubing can be accommodated by changing the sleeve (see Annex D). In the past, these connectors have been used predominantly with inch tubing. For new and future designs, the us
30、e of metric tubing is preferred. This part of ISO 8434 also specifies a performance and qualification test for O-ring face seal connectors. 2 Normative references The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited a
31、pplies. For undated references, the latest edition of the referenced document (including any amendments) applies. ISO 48, Rubber, vulcanized or thermoplastic Determination of hardness (hardness between 10 IRHD and 100 IRHD) ISO 68-2, ISO general-purpose screw threads Basic profile Part 2: Inch screw
32、 threads ISO 261, ISO general-purpose metric screw threads General plan ISO 263, ISO inch screw threads General plan and selection for screws, bolts and nuts Diameter range 0,06 to 6 in ISO 3304, Plain end seamless precision steel tubes Technical conditions for delivery 3) 1 bar = 0,1 MPa = 10 5Pa;
33、1 MPa = 1N/mm 2 . BS ISO 8434-3:20052 ISO 3305, Plain end welded precision steel tubes Technical conditions for delivery ISO 3601-3: 4) , Fluid systems Sealing devices O-rings Part 3: Quality acceptance criteria ISO 4759-1, Tolerances for fasteners Part 1: Bolts, screws, studs and nuts Product grade
34、s A, B and C ISO 5598, Fluid power systems and components Vocabulary 5)ISO 5864, ISO inch screw threads Allowances and tolerances ISO 6149-1, Connections for fluid power and general use Ports and stud ends with ISO 261 threads and O-ring sealing Part 1: Ports with O-ring seal in truncated housing 6)
35、ISO 6149-2: 7) , Connections for fluid power and general use Ports and stud ends with ISO 261 threads and O-ring sealing Part 2: Heavy-duty (S series) stud ends Dimensions, design, test methods and requirements ISO 8434-1, Metallic tube connections for fluid power and general use Part 1: 24 cone con
36、nectors 8)ISO 8434-2, Metallic tube connections for fluid power and general use Part 2: 37 flared fittings ISO 9227, Corrosion tests in artificial atmospheres Salt spray tests ISO 12151-1, Connections for hydraulic fluid power and general use Hose fittings Part 1: Hose fittings with ISO 8434-3 O-rin
37、g face seal ends ISO 19879, Metallic tube connections for fluid power and general use Test methods for hydraulic fluid power connections 9)3 Terms and definitions For the purposes of this document, the terms and definitions given in ISO 5598, ISO 8434-1 and ISO 8434-2, and the following apply. 3.1 f
38、luid power means whereby energy is transmitted, controlled and distributed using a pressurized fluid as the medium ISO 5598 3.2 connector leakproof device to connect pipelines (conductors) to one another, or to equipment ISO 5598 4) To be published. (Revision of ISO 3601-3:1987) 5) To be published.
39、(Revision of ISO 5598:1985) 6) To be published. (Revision of ISO 6149-1:1993) 7) To be published. (Revision of ISO 6149-2:1993) 8) To be published. (Revision of ISO 8434-1:1994 and ISO 8434-4:1995) 9) To be published. (Revision of ISO 8434-5:1995) BS ISO 8434-3:20053 3.3 fastening thread terminal th
40、read of a complete connector 3.4 run two principal, axially aligned outlets of a tee or cross 3.5 branch side outlet of a tee or cross 3.6 chamfer removal of a conical portion at the entrance of a thread to assist assembly and prevent damage to the start of the thread 3.7 assembly torque torque to b
41、e applied in order to achieve a satisfactory final assembly 3.8 working pressure pressure at which the apparatus is being operated in a given application ISO 5598 3.9 adjustable stud end stud end connector that allows for connector orientation through final tightening of the locknut to complete the
42、connection NOTE This type of stud end is typically used on shaped connectors (e.g. tees, crosses and elbows). 3.10 nonadjustable stud end stud end connector that does not require specific orientation through final tightening of the connection, because it is only used on straight connectors 4 Materia
43、ls 4.1 General Figure 1 shows the cross-selection and components of a typical O-ring face seal connector. 4.2 Connector bodies Bodies shall be manufactured from carbon steel that will provide the minimum pressure/temperature requirements specified in Clause 5, when tested in accordance with Clause 1
44、5. They shall have characteristics that make them suitable for use with the fluid to be conveyed and that will provide an effective joint. Weld-on sleeves shall be made of materials classified as suitable for welding. 4.3 Nuts Nuts to be used with carbon steel bodies shall be made of carbon steel, u
45、nless otherwise specified. In tube assemblies where sleeves are copper brazed, nuts become annealed, reducing their strength. Nuts for copper brazed assemblies shall be made from suitable, higher strength material to meet the performance requirements in 15.1. High-strength nuts (style B nuts) shall
46、be identified by a turned diameter, d 14 , as shown in Figure 5. BS ISO 8434-3:20054 Key 1 straight stud connector body 2 tube nut 3 tube 4 braze-on sleeve 5 O-ring a Stud end in accordance with ISO 6149-2. Figure 1 Cross-section and components of typical O-ring face seal connector body 4.4 O-rings
47、Unless otherwise specified, for use with petroleum-based hydraulic fluids at the pressure and temperature requirements in Clause 5 and Table 1 and for testing, the O-rings shall be made of NBR (nitrile) with a hardness of (90 5) IRHD, measured per ISO 48, and shall conform to the dimensions given in
48、 Table 6 and shall meet or exceed the O-ring quality acceptance criteria for grade N of ISO 3601-3:. In those cases, where the pressure and temperature requirements of this part of ISO 8434 and/or the hydraulic fluid used in the system differ from those specified in Clause 5 and Table 1, the connect
49、or manufacturer shall be consulted to ensure that an appropriate O-ring material is selected. 5 Pressure/temperature requirements 5.1 Connectors in conformance with this part of ISO 8434 made of carbon steel shall meet or exceed without leakage the requirements from a vacuum of 6,5 kPa (0,065 bar) absolute pressure to the working pressures given in Table 1 when used at temperatures betwe
