1、 g49g50g3g38g50g51g60g44g49g42g3g58g44g55g43g50g56g55g3g37g54g44g3g51g40g53g48g44g54g54g44g50g49g3g40g59g38g40g51g55g3g36g54g3g51g40g53g48g44g55g55g40g39g3g37g60g3g38g50g51g60g53g44g42g43g55g3g47g36g58control valves Part 3: Test methods for pressure control valvesICS 23.100.50Hydraulic fluid power E
2、lectrically modulated hydraulic BRITISH STANDARDBS ISO 10770-3:2007BS ISO 10770-3:2007This British Standard was published under the authority of the Standards Policy and Strategy Committee on 30 November 2007 BSI 2007ISBN 978 0 580 54792 8Amendments issued since publicationAmd. No. Date Commentscont
3、ract. Users are responsible for its correct application.Compliance with a British Standard cannot confer immunity from legal obligations.National forewordThis British Standard is the UK implementation of ISO 10770-3:2007.The UK participation in its preparation was entrusted by Technical Committee MC
4、E/18, Fluid power systems and components, to Panel MCE/18/-/8, Product testing.A list of organizations represented on this committee can be obtained on request to its secretary.This publication does not purport to include all the necessary provisions of a Reference numberISO 10770-3:2007(E)INTERNATI
5、ONAL STANDARD ISO10770-3First edition2007-10-15Hydraulic fluid power Electrically modulated hydraulic control valves Part 3: Test methods for pressure control valvesTransmissions hydrauliques Distributeurs hydrauliques modulation lectrique Partie 3: Mthodes dessai pour distributeurs de commande de p
6、ressionBS ISO 10770-3:2007ii iiiContents Page Foreword iv Introduction v 1 Scope . 1 2 Normative references . 1 3 Terms, definitions and symbols 1 3.1 Terms and definitions. 1 3.2 Symbols . 3 3.3 Graphic symbols. 3 4 Standard test conditions 3 5 Test installation. 4 6 Accuracy 8 6.1 Instrument accur
7、acy. 8 6.2 Dynamic range 8 7 Electrical tests for valves without integrated electronics 8 7.1 General. 8 7.2 Coil resistance 8 7.3 Coil inductance (optional test) 8 7.4 Insulation resistance 10 8 Relief-valve performance tests 10 8.1 Steady-state tests . 10 8.2 Dynamic tests 18 9 Reducing valves 23
8、9.1 Performance tests. 23 9.2 Dynamic tests 30 10 Pressure impulse test. 34 11 Presentation of results. 34 11.1 General. 34 11.2 Test reports . 34 12 Identification statement 36 Annex A (informative) Testing guidance 37 Bibliography . 38 BS ISO 10770-3:2007iv Foreword ISO (the International Organiza
9、tion 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 interested in a subject for which a technical committee has been established
10、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 Commission (IEC) on all matters of electrotechnical standardization. In
11、ternational 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 technical committees are circulated to the member bodies for voting. Publi
12、cation 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 shall not be held responsible for identifying any or all such patent r
13、ights. ISO 10770-3 was prepared by Technical Committee ISO/TC 131, Fluid power systems, Subcommittee SC 8, Product testing. ISO 10770 consists of the following parts, under the general title Hydraulic fluid power Electrically modulated hydraulic control valves: Part 1: Test methods for four-way dire
14、ctional flow control valves Part 2: Test methods for three-way directional flow control valves Part 3: Test methods for pressure control valves BS ISO 10770-3:2007vIntroduction This part of ISO 10770 describes methods of testing electrohydraulic pressure relief and pressure reducing valves. These ty
15、pes of electrohydraulic valves prevent the pressure in a hydraulic system rising above a level defined or set by an electrical input signal. Relief valves are used to control the pressure in a closed volume by increasing the flow out of the volume if the pressure exceeds the set pressure level. The
16、excess flow is dumped directly to a tank. Reducing valves are used to control the pressure in a closed volume by restricting the flow into the volume if the pressure exceeds the set pressure level. The design of the system and the position of the valve within the system dictates which type of valve
17、is appropriate to use. This part of ISO 10770 has been prepared with the intention of improving the uniformity of valve testing and hence the consistency of recorded valve performance data so that these data can be used for system design, regardless of the data source. BS ISO 10770-3:2007blank1Hydra
18、ulic fluid power Electrically modulated hydraulic control valves Part 3: Test methods for pressure control valves 1 Scope This part of ISO 10770 describes test methods for determining the performance characteristics of electrically modulated hydraulic pressure control valves. 2 Normative references
19、The following referenced documents are indispensable for the application of this document. For dated references, only the edition cited applies. For undated references, the latest edition of the referenced document (including any amendments) applies. ISO 1219-1, Fluid power systems and components Gr
20、aphic symbols and circuit diagrams Part 1: Graphic symbols for conventional use and data-processing applications ISO 3448:1992, Industrial liquid lubricants ISO viscosity classification ISO 4406, Hydraulic fluid power Fluids Method for coding level of contamination by solid particles ISO 5598, Fluid
21、 power systems and components Vocabulary ISO 6743-4, Lubricants, industrial oils and related products (Class L) Classification Part 4: Family H (Hydraulic systems) ISO 9110-1:1990, Hydraulic fluid power Measurement techniques Part 1: General measurement principles ISO 10771-1, Hydraulic fluid power
22、Fatigue pressure testing of metal pressure-containing envelopes Part 1: Test method IEC 60617-DB, Graphical symbols for diagrams 3 Terms, definitions and symbols 3.1 Terms and definitions For the purposes of this document, the terms and definitions given in ISO 5598 and the following apply. 3.1.1 el
23、ectrically modulated pressure control valve valve that limits the pressure in a hydraulic system to a level that is continuously variable and proportional to an electrical input signal BS ISO 10770-3:20072 3.1.2 electrically modulated relief valve valve that limits the pressure at the inlet port by
24、dumping excess flow to the tank port 3.1.3 electrically modulated reducing valve electrically modulated pressure control valve that limits the pressure at the outlet port by reducing the flow taken from the inlet port 3.1.4 controlled pressure pressure difference between inlet and outlet of the reli
25、ef valve under test or the pressure at the outlet of the reducing valve under test 3.1.5 controlled pressure volume total volume of fluid in a test rig directly connected to the inlet to a relief valve under test, or the outlet of the reducing valve under test 3.1.6 headloss minimum pressure drop th
26、rough a valve NOTE The headloss is usually plotted as pressure versus flow. 3.1.7 reference pressure controlled pressure measured at 10 % of rated flow BS ISO 10770-3:200733.2 Symbols For the purposes of this document, the symbols given in Table 1 apply. Table 1 Symbols Parameter Symbol Unit Inducta
27、nce LCH Insulation resistance Ri Resistance RC External test resistance R Dither amplitude % (of max. input signal) Dither frequency Hz Input signal I or U A or V Rated signal INor UNA or V Current readout IREADA Output flow q l/min Rated flow qNl/miPressure gain KP= (p/I or p/U) bar (per input sign
28、al unit) Hysteresis % (of max. output) Internal leakage qIl/min Supply pressure pPMPa (bar) Return pressure pTMPa (bar) Controlled pressure pCP (bar) Valve pressure drop pV= pP pTMPa (bar) Rated pressure pNMP (bar) Threshold % (of maximum input) Amplitude (ratio) dB Phase lag Temperature C Frequency
29、 f Hz Time t s Time constant tC3.3 Graphic symbols The graphic symbols in this part of ISO 10770 conform to ISO 1219-1 and IEC 60617-DB. 4 Standard test conditions Unless otherwise specified, tests shall be carried out using the standard conditions given in Table 2. BS ISO 10770-3:20074 Table 2 Stan
30、dard test conditions Parameter Condition Ambient temperature 20 C 5 C Filtration Solid contaminant code number shall be stated in accordance with ISO 4406. Fluid type Commercially available mineral based hydraulic fluid (i.e., L - HL in accordance with ISO 6743-4 or other fluid with which the valve
31、is able to operate) Fluid viscosity 32 cSt 8 cSt at valve inlet Viscosity grade Grade VG32 or VG46 in accordance with ISO 3448:1992 Supply pressure Test requirement 2,5 % Return pressure Return pressure shall conform to the manufacturers recommendations. 5 Test installation A test installation confo
32、rming to the requirements of Figures 1, 2 or 3 shall be used for testing all valves. SAFETY PRECAUTIONS It is essential that consideration is given to the safety of personnel and equipment during the tests. Figures 1 to 3 show the minimum items required to carry out the tests without any safety devi
33、ces to protect against damage in the event of component failure. For tests using the test circuits shown in Figures 1 to 3, the following apply. a) Guidance on carrying out the tests is given in Annex A. b) A separate circuit may be constructed for each type of test. This can improve the accuracy of
34、 test results as it eliminates the possibility of leakage through the shut-off valves. c) Hydraulic performance tests are carried out on a combination of valve and amplifier. Input signals are applied to the amplifier and not directly to the valve. For electrical tests, the signals are applied direc
35、tly to the valve. d) If possible, hydraulic tests should be conducted using an amplifier recommended by the valve manufacturer. If not, the type of amplifier used should be recorded, with the operating details (i.e. pulse width modulation frequency, dither frequency and amplitude). e) The amplifier
36、supply voltage and magnitude and sign of the voltage applied to the valve during the on and off periods of the pulse-width modulation should be recorded. f) Electronic test equipment and transducers should have a bandwidth or natural frequency at least ten times greater than the maximum test frequen
37、cy. g) Flow transducer 10 shall be selected so as to have negligible effect on the pressure at port Y. BS ISO 10770-3:20075Key 1 flow source 2 system relief valve 3 pilot valve for unloading valve 4 unloading valve 5 unit under test 6 pressure transducer 7 pressure transducer 8 differential amplifie
38、r 9 data acquisition 10 flow transducer 11 flow transducer 12 signal generator 13 temperature indicator 14 pressure gauge 15 pressure gauge S1 shut-off valve S2 shut-off valve P supply port T return port Y pilot-drain port Figure 1 Relief-valve test circuit BS ISO 10770-3:20076 Key 1 flow source 2 s
39、ystem relief valve 3 flow control valve 4 temperature indicator 5 unit under test 6 data acquisition 7 pressure transducer 8 pressure gauge 9 pressure gauge 10 flow transducer 11 flow transducer 12 signal generator A control-pressure port B inlet-pressure port S1 shut-off valve Y pilot-drain port Fi
40、gure 2 Reducing valve test circuit BS ISO 10770-3:20077Key 1 flow source 2 system relief valve 3 flow control valve 4 temperature indicator 5 unit under test 6 data acquisition 7 pressure transducer 8 pressure gauge 9 pressure gauge 10 flow transducer 11 flow transducer 12 signal generator 13 direct
41、ional valve A control pressure port B inlet pressure port S1 shut off valve T return pressure port Y pilot drain port Figure 3 Reducing valve with reverse flow test circuit BS ISO 10770-3:20078 6 Accuracy 6.1 Instrument accuracy Instrumentation shall be accurate to within the limits specified in ISO
42、 9110-1:1990, Class B: a) electrical resistance: 2 % of the actual measurement; b) pressure: 1 % of the valve under test rated pressure; c) temperature: 2 % of the ambient temperature; d) flow: 2,5 % of the valve under test rated flow; e) demand: 1,5 % of the electrical demand signal required to ach
43、ieve the rated pressure. 6.2 Dynamic range For the dynamic tests, ensure that the pressure transducers, amplifiers and recording devices do not generate any damping, attenuation or phase shift of the pressure signal being recorded. 7 Electrical tests for valves without integrated electronics 7.1 Gen
44、eral As appropriate, perform the tests described in 7.2 to 7.4 on all valves without integrated electronics before proceeding to subsequent tests. NOTE Tests 7.2 to 7.4 only apply to current-driven valves. 7.2 Coil resistance 7.2.1 Coil resistance (cold) a) Soak the complete un-energized valve at th
45、e specified ambient temperature for at least 2 h. b) Measure and record the electrical resistance between the two leads or terminals of each coil in the valve. 7.2.2 Coil resistance (hot) a) Soak the complete, energized valve, mounted on a subplate as recommended by the manufacturer, at its maximum
46、rated temperature and operate the complete valve, fully energized and without flow until the coil temperature stabilizes. b) Measure and record the electrical resistance between the two leads or terminals of each coil in the valve. The resistance value shall be measured within 1 s of removing the su
47、pply voltage. 7.3 Coil inductance (optional test) This test method shall not be considered to determine a definitive value of inductance. The value obtained shall be used for comparison purposes only. Perform the test as follows. a) Connect the coil to a constant voltage supply capable of delivering
48、 at least the rated current of the coil. b) Hold the armature stationary at 50 % of its working stroke during the test. BS ISO 10770-3:20079c) Monitor the coil current using an oscilloscope or similar equipment. d) Adjust the voltage so that the steady-state current equals the rated current of the c
49、oil. e) Switch the voltage off then on and record the current transient behaviour. f) Determine the time constant, tC, of the coil (see Figure 4) and calculate the inductance, LC, using Equation (1): LC= RCtC(1) where RCis the coil resistance, expressed in ohms. Key X time Y current, in percent 1 DC current trace 2 initiation 3 time constant, tCFigure 4 Coil inductance measurement BS ISO 10770-3:200710 7.4 Insulation resistance Establish the ins
