1、BRITISH STANDARD BS 7791:1995 ISO 10448: 1994 Agricultural tractors Hydraulic pressure for implementsBS7791:1995 This British Standard, having been prepared under the directionof the Engineering SectorBoard (E/-), was publishedunder the authorityofthe Standards Boardand comes into effect on 15 Febru
2、ary 1995 BSI 09-1999 The following BSI references relate to the work on this standard: Committee reference AGE/32 Draft for comment 92/71886 DC ISBN 0 580 23688 9 Committees responsible for this British Standard The preparation of this British Standard was entrusted by the Engineering Sector Board t
3、o Technical Committee AGE/32, upon which the following bodies were represented: Agricultural and Allied Workers National Trade Group Agricultural Engineers Association British Fluid Power Association Department of Transport Health and Safety Executive Local Authority Organisations Ministry of Agricu
4、lture, Fisheries and Food National Farmers Union Silsoe Research Institute Coopted members Amendments issued since publication Amd. No. Date CommentsBS7791:1995 BSI 09-1999 i Contents Page Committees responsible Inside front cover National foreword ii 1 Scope 1 2 Normative references 1 3 Definitions
5、 1 4 Requirements 1 Table 1 2 List of references Inside back coverBS7791:1995 ii BSI 09-1999 National foreword This British Standard has been prepared under the direction of the Engineering Sector Board and is identical withISO10448:1994 Agricultural tractors Hydraulic pressure for implements, publi
6、shed by the International Organization for Standardization (ISO). ISO 10448 was prepared by Subcommittee SC4, Tractors, of ISO Technical Committee 23, Tractors and machinery for agriculture and forestry. The Technical Committee has reviewed the provisions of ISO730-1 (92/85474 DC),ISO789-10 (94/7065
7、72 DC), ISO6149-1:1993,ISO6149-2:1993 andISO6149-3:1993, to which normative reference is made in the text, and has decided that they are acceptable for use in conjunction with this standard. A British Standard does not purport to include all the necessary provisions of a contract. Users of British S
8、tandards are responsible for their correct application. Compliance with a British Standard does not of itself confer immunity from legal obligations. Cross-reference International Standard Corresponding British Standard ISO 5675:1992 BS 4742 Hydraulic equipment for agricultural machinery Part 2:1993
9、 Specification for quick-action hydraulic couplers for general purposes Summary of pages This document comprises a front cover, an inside front cover, pages i and ii, pages1 and 2, an inside back cover and a back cover. This standard has been updated (see copyright date) and may have had amendments
10、incorporated. This will be indicated in the amendment table on the inside front cover.BS7791:1995 BSI 09-1999 1 1 Scope This International Standard specifies the characteristics of the hydraulic pressure from agricultural tractors to connect hydraulic devices on implements, to permit interchangeable
11、 use of various types of implements using remote cylinders and other hydraulic devices. It applies to agricultural tractors intended for interchangeable implements. 2 Normative references The following standards contain provisions which, through reference in this text, constitute provisions of this
12、International Standard. At the time of publication, the editions indicated were valid. All standards are subject to revision, and parties to agreements based on this International Standard are encouraged to investigate the possibility of applying the most recent editions of the standards indicated b
13、elow. Members of IEC and ISO maintain registers of currently valid International Standards. ISO 730-1:, Agricultural wheeled tractors Rear-mounted three-point linkage Part 1: Categories1,2, 3 and 4 1) . ISO 789-10:, Agricultural tractors Test procedures Part 10: Hydraulic power at tractor/implement
14、interface 2) . ISO 5675:1992, Agricultural tractors and machinery General purpose quick-action hydraulic couplers. ISO 6149-1:1993, Connections for fluid power and general use Ports and stud ends withISO261 threads and O-ring sealing Part 1: Ports with O-ring seal in truncated housing. ISO 6149-2:19
15、93, Connections for fluid power and general use Ports and stud ends withISO261 threads and O-ring sealing Part 2: Heavy-duty (Sseries) stud ends Dimensions, design, test methods and requirements. ISO 6149-3:1993, Connections for fluid power and general use Ports and stud ends withISO261 threads and
16、O-ring sealing Part 3: Light-duty (Lseries) stud ends Dimensions, design, test methods and requirements. 3 Definitions For the purposes of this International Standard, the following definitions apply. 3.1 external hydraulic service source of hydraulic power, derived from the hydraulic system of the
17、agricultural tractor, available for use on an implement mounted on, coupled to or otherwise used in conjunction with it 3.2 coupler pair pair of female hydraulic couplers compatible with male couplers specified inISO5675, mounted on agricultural tractors and connected to the hydraulic system to allo
18、w flow from one coupler to the other 3.3 available differential pressure steady state difference in hydraulic pressure between two coupler parts on the implement side 3.4 maximum pressure maximum steady state hydraulic pressure at either male coupler connected to a coupler pair 3.5 maximum loop retu
19、rn pressure maximum steady hydraulic pressure at the male coupler returning flow to a hydraulic system that can reverse the flow through that coupler 3.6 maximum sump return pressure 1) With coupler: Maximum steady state hydraulic pressure at the male coupler returning flow directly to the reservoir
20、. 2) Without coupler: Maximum steady state hydraulic pressure at an M22 1,5or M27 2thread size port in accordance with ISO6149-1,ISO6149-2 orISO6149-3, returning flow directly to the reservoir. 3.7 peak pressure maximum instantaneous hydraulic pressure at either male coupler connected to a coupler p
21、air 4 Requirements Pressures as listed inTable 1 should be within their limits as the flow is varied between the specified flow range limits and the loop oil temperature remains within limits. The pressures shall be measured on the implement side (male couplers) which conform to size12,5inISO5675. T
22、he test method shall be in accordance withISO789-10. 1) To be published. (Revision ofISO730-1:1990) 2) To be published.BS7791:1995 2 BSI 09-1999 Table 1 Characteristic Value Maximum pressure 20,5 MPa (205 bar) Minimum differential pressure 15 MPa (150 bar) Maximum loop return pressure 1 MPa (10 bar)
23、 Maximum sump return pressure, with coupler 0,5 MPa (5 bar) Maximum sump return pressure, without coupler 0,2 MPa (2 bar) Peak pressure 29 MPa (290 bar) Specified flow range 0 to 30 l/min for category 1 tractors a 0 to 50 l/min for categories 2 and 3 tractors a Oil temperature 65 C 5 C NOTEThe speci
24、fied flow range of0to30l/min is recommended for partial-consuming (e.g.10l/min to30l/min) devices and of0to50l/min for continuous-consuming (e.g.35l/min to50l/min) devices. a Categories according toISO730-1.BS7791:1995 BSI 09-1999 List of references See national foreword.BS 7791:1995 ISO 10448: 1994
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