1、BRITISH STANDARD BS 4062-2: 1990 ISO 6403:1988 Valves for hydraulic fluid power systems Part 2: Methods for determining performance UDC 621.646.2/.4:621.22:532.57.08:620.1BS4062-2:1990 This BritishStandard, having been prepared under the directionof the Machinery andComponents Standards PolicyCommit
2、tee, was publishedunder the authorityofthe Board of BSIandcomes into effect on 29June1990 BSI 12-1999 First published as BS4062 September1966 First revision as BS4062-2 July1982 Second revision June1990 The following BSI references relate to the work on this standard: Committee reference MCE/18 Draf
3、t for comment 85/79297 DC ISBN 0 580 17841 2 Committees responsible for this BritishStandard The preparation of this BritishStandard was entrusted by the Machinery and Components Standards Policy Committee (MCE/-) to Technical Committee MCE/18, upon which the following bodies were represented: Advan
4、ced Manufacturing Technology Research Institute Association of British Mining Equipment Companies Bath University Library British Compressed Air Society British Fluid Power Association British Hydromechanics Research Association British Steel Industry British Telecommunications plc Department of Tra
5、de and Industry (National Engineering Laboratory) Electricity Supply Industry in England and Wales Federation of Manufacturers of Construction Equipment and Cranes Health and Safety Executive Institution of Mechanical Engineers Ministry of Defence The following bodies were also represented in the dr
6、afting of the standard, through sub-committees and panels: British Railways Board Society of Motor Manufacturers and Traders Limited Amendments issued since publication Amd. No. Date of issue CommentsBS4062-2:1990 BSI 12-1999 i Contents Page Committees responsible Inside front cover National forewor
7、d iii 0 Introduction 1 1 Scope and field of application 1 2 References 1 3 Definitions 1 4 Symbols and units 1 5 Test installation General requirements 1 6 General test conditions 3 7 Test procedure for directional control valves 3 8 Test procedure for non-return (check) valves 5 9 Test procedure fo
8、r valves controlling pressure 6 10 Test procedure for flow control valves 7 11 Test procedure for flow-dividing valves 8 12 Test report 9 13 Identification statement 11 Annex A Classes of measurement accuracy 27 Annex B Use for practical units 27 Figure 1 Test circuit for directional control valves
9、11 Figure 2 Switching envelope for directional control valves 12 Figure 3 Transient characteristics for operation of directional control valves Relationship between displacement and time 12 Figure 4 Transient characteristics for operation of directional control valves Relationship between pressure a
10、nd time 13 Figure 5 Test circuit for direct-acting non-return valves 13 Figure 6 Test circuit for leakage flow of direct-acting non-return valves 14 Figure 7 Test circuit for pilot-pressure-operated non-return valves 15 Figure 8 Test circuit for pressure-relief valves 16 Figure 9 Test circuit for pr
11、essure-reducing valves 17 Figure 10 Test circuit for flow control valves (meter-in and three-way bleed-off) 18 Figure 11 Test circuit for flow control valves (meter-out) 19 Figure 12 Test circuit for flow control valves (bleed-off) 20 Figure 13 Test circuit for flow-dividing valves 21 Figure 14 Grap
12、hical representation of pressure/flow characteristics of pilot-pressure-operated non-return valves 22 Figure 15 Graphical representation of pilot pressures p Xpermitting flow from port B to port A 22 Figure 16 Graphical representation of steady-state pressure/flow characteristics for pressure-relief
13、 valves 23 Figure 17 Graphical representation of transient response of valve controlling pressure 24 Figure 18 Graphical representation of steady-state flow characteristics of a flow control valve 25 Figure 19 Graphical representation of transient response of flow control valves 26BS4062-2:1990 ii B
14、SI 12-1999 Page Table 1 Symbols and units 2 Table 2 Limits of permissible variation of mean indicated values of controlled parameters 3 Table 3 Output pressure conditions 8 Table 4 Permissible systematic errors of measuring instruments as determined during calibration 27 Table 5 Practical units 27 P
15、ublications referred to Inside back coverBS4062-2:1990 BSI 12-1999 iii National foreword This revised BritishStandard, prepared under the direction of the Machinery and Components Standards Policy Committee, concerns the testing of valves used in hydraulic fluid power systems and supersedes BS4062:1
16、982, which is withdrawn. This Part of BS4062 describes methods for determining the performance of valves under steady-state and dynamic conditions; they are identical with the methods described in ISO6403:1988 “Hydraulic fluid power Valves controlling flow and pressure Test methods”, published by th
17、e International Organization for Standardization (ISO). The standard is published in two Parts, Part1 of which describes a method for determining the pressure differential/flow characteristics of valves under steady-state conditions. Three classes of measurement accuracy, A, B and C are associated w
18、ith the tests and are related in Annex A. The class of measurement accuracy should be agreed between manufacturer and user. The methods of measurement used for testing the majority of valves will be those included in class C, those in class B may be employed where a higher degree of accuracy is requ
19、ired. Class A methods of measurement will necessitate laboratory conditions, and may be employed exceptionally on tests where the attainment of high accuracy is held to justify the greatly increased time and cost expended. It is intended that the standard will unify testing methods and enable the pe
20、rformance of different types of valve to be more readily compared. This revised edition of ISO6403:1988 corrects inaccuracies in9.3 of the first edition and also incorporates other improvements. The Technical Committee has reviewed the provisions of ISO5598, to which reference is made in the text, a
21、nd has decided that they are acceptable for use in conjunction with this standard. Additional information. For the purposes of this BritishStandard, the identification statement in clause13 should be read as follows: “Tests for determining steady-state and dynamic performance conform to the appropri
22、ate methods described in BS4062-2:1989.” A British Standard does 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.
23、Cross-references International Standard Corresponding BritishStandard ISO 1219:1976 BS 2917:1977 Specification for graphical symbols used on diagrams for fluid power systems and components (Identical) ISO 4411:1986 BS 4062 Valves for hydraulic fluid power systems Part 1:1982 Methods for determining
24、pressure differential/flow characteristics (Identical) IEC Publication 85(1984) BS 2757:1986 Method for determining the thermal classification of electrical insulation (Identical) Summary of pages This document comprises a front cover, an inside front cover, pagesi toiv, pages1 to28, an inside back
25、cover and a back cover. This standard has been updated (see copyright date) and may have had amendments incorporated. This will be indicated in the amendment table on the inside front cover.iv blankBS4062-2:1990 BSI 12-1999 1 0 Introduction In hydraulic fluid power systems, power is transmitted and
26、controlled through a liquid under pressure within an enclosed circuit. Hydraulic valves may be used to control the direction, pressure or flow rate of the working fluid by adjusting or controlling their resistance to flow. ISO4411, in which methods for determining the steady-state differential press
27、ure/flow characteristics of hydraulic valves are specified, forms part of the same series of International Standards. The test requirements for production purposes may differ from those specified in this International Standard. 1 Scope and field of application This International Standard specifies m
28、ethods for testing hydraulic valves which are used for the control of flow or pressure in a circuit in order to determine their steady-state and dynamic performance. Requirements for test installations and procedures, measurements and presentation of results are specified. This International Standar
29、d does not establish limits of performance since the suitability of the valve for its intended purpose should be agreed between the manufacturer and the user. Accuracy of measurement is divided into three classes (A, B and C) which are explained in Annex A. Guidance as to the use of practical units
30、for the presentation of results is given in Annex B. Proportional control valves are not dealt with in this International Standard. Electrohydraulic servovalves are dealt with in ISO6404. 2 References ISO 1219, Fluid power systems and components Graphic symbols. ISO 4411, Hydraulic fluid power Valve
31、s Determination of pressure differential/flow characteristics. ISO 5598, Fluid power systems and components Vocabulary. IEC Publication 85, Thermal evaluation and classification of electrical insulation. 3 Definitions For the purposes of this International Standard, the definitions given in ISO5598,
32、 together with the following, apply. 3.1 bleed-off a circuit condition where there is control over the inlet flow to a component by diverting part of that flow to a reservoir or part of a circuit having lower pressure 3.2 meter-in a circuit condition where there is control over the inlet flow to a c
33、omponent 3.3 meter-out a circuit condition where there is control over the outlet flow from a component 3.4 volumetric stiffness the stiffness of a given portion of a hydraulic circuit, which is determined by the value of the partial differentialfor the fluid contained in that part of the circuit 4
34、Symbols and units 4.1 The units and symbols used throughout this International Standard are as shown in Table 1. 4.2 The graphical symbols used in the figures depicting test circuits are in accordance with ISO1219. 5 Test installation General requirements 5.1 Test circuit 5.1.1 A test circuit simila
35、r to those shown in Figure 1 and Figure 5 to Figure 13 and suitable for the type of valve being tested in accordance with the relevant clauses in this International Standard shall be used. NOTE 1Although Figure 1 and Figure 5 to Figure 13 illustrate basic circuits which are specific to one or more t
36、ests and which utilize the minimum number of components, it is acceptable to use an integrated test circuit which embraces two or more test conditions. NOTE 2The figures in this International Standard showing basic test circuits do not incorporate all the safety devices necessary to protect against
37、damage in the event of component failure. It is important that those responsible for conducting these tests give due consideration to safeguarding both personnel and equipment. p V -BS4062-2:1990 2 BSI 12-1999 Table 1 Symbols and units 5.1.2 A fluid supply with a controllable flow which has a higher
38、 maximum than the rated flow of the valve being tested shall be used. 5.1.3 A pressure control valve in the supply line shall be installed to protect the circuit from excess pressure. Further control valves, as necessary, shall be installed to regulate the flow or pressure, as required, in various p
39、arts of the circuit. 5.1.4 The inside diameters of pipes and fittings that interface with the test valve, and which include pressure tapping points, shall be consistent with the diameters of the ports. 5.1.5 Drain ports shall be connected to a reservoir. 5.2 Pressure- and temperature-sensing points
40、5.2.1 Location of pressure tappings NOTEIn the case of measurements to class C standard of accuracy (seeAnnex A), pressure readings taken for expediency at other points other than those described in this sub-sub-clause will give sufficient accuracy providing that, where appropriate, correction is ma
41、de for pipe losses. Pressure tappings shall be provided both upstream and downstream of the valve being tested and, if required, at other points. 5.2.1.1 The inlet pressure tapping point shall be a) not less than 10d downstream of any perturbation-producing element, such as a valve or a bend, and b)
42、 not less than 5d upstream of the test valve. 5.2.1.2 The outlet pressure tapping point shall be not less than10d downstream of the test valve. 5.2.1.3 The measured data for pipe losses shall be corrected using the method described in ISO4411. 5.2.2 Pressure tappings 5.2.2.1 The tappings shall have
43、diameters equal to or less than0,1d but not less than1mm nor greater than6mm. 5.2.2.2 The internal pipe surface at the tapping shall be deburred without the sharp edge of the tapping hole being removed. 5.2.2.3 The length of the tapping hole shall be not less than twice the diameter. 5.2.2.4 The bor
44、e of the pipe containing the tapping shall be clean and smooth. 5.2.2.5 The instrument-connecting pipes shall have bores not less than3mm. 5.2.2.6 Any entrained air between each tapping point and the measuring instrument shall be purged. 5.2.3 Location of temperature-sensing point The fluid temperat
45、ure at the inlet to the test valve shall be measured at a distance not greater than15d upstream of the inlet pressure tapping. 5.3 Filtration and contamination level 5.3.1 Filters shall be installed which provide a standard of filtration which is at least equal to that recommended by the test valve
46、manufacturer. 5.3.2 The position and specific description of each filter used in the test circuit shall be stated in the test report. 5.3.3 During tests conducted in accordance with clauses7 to11, where inconsistencies may arise due to silting, the standard of filtration shall be such that test meas
47、urements can be made within60s; the actual interval in the test report shall be stated in the test report. 5.3.4 The actual contamination level of the test fluid from samples taken during the test shall be determined; the test method used shall be stated in the test report. Quantity Symbol Dimension
48、 a SI unit b Nominal diameter of valve Force Control element linear displacement Control element angular displacement Volume flow rate Internal diameter of pipe Pressure, differential pressure Time Mass density of fluid Kinematic viscosity Temperature (customary) Isentropic bulk modulus Volume D F L
49、 q V d p, %p t v K s V L MLT 2 L L 3 T 1 L ML 1 T 2 T ML 3 L 2 T 1 G ML 1 T 2 L 3 m N m rad m 3 /s m Pa s kg/m 3 m 2 /s C Pa m 3 a M = mass; L = length; T = time; G = temperature b The practical units which may be used for the presentation of results are tabulated in Annex B.BS4062-2:1990 BSI 12-1999 3 6 General test conditions 6.1 Test fluid 6.1.1 The following information relating to the test fluid shall be included in the test report: a) a description of test fluid; b) the kin
