This standard specifies the method for evaluating the contamination sensitivity of hydraulic valves. This method evaluates the performance changes of valves caused by solid particle contaminants from the two aspects of contamination jamming and contamination wear/erosion. The purpose of this test is mainly to compare the sensitivity of different types of hydraulic valves to particulate contaminants under the same test conditions. Since it is impossible to test all working conditions that may occur on site, the test results are not used as a basis for quantitatively evaluating the performance of hydraulic valves under actual on-site contamination conditions. This evaluation method can be used to obtain the effects of different particle sizes and contamination concentrations on hydraulic valve contamination jamming and contamination wear/erosion, thereby determining the filtration requirements required to protect the hydraulic valve. This standard is applicable to all types of hydraulic valves with hydraulic oil (liquid) as the working medium. JB/T 7857-1995 Method for evaluating the contamination sensitivity of hydraulic valves JB/T7857-1995 Standard download decompression password: www.bzxz.net

Mechanical Industry Standard of the People's Republic of China
JB/T 7857-1995
Evaluation Method of Hydraulic Valve Contamination Sensitivity
Published on December 1, 1995
Ministry of Machinery Industry of the People's Republic of China
Implementation on July 1, 1996
Mechanical Industry Standard of the People's Republic of China
Evaluation Method of Hydraulic Valve Contamination Sensitivity
Subject Content and Scope of Application
JB/T7857-1995
This standard specifies the evaluation method of hydraulic valve contamination sensitivity. This method evaluates the performance changes of valves caused by solid particle contaminants from two aspects: contamination clamping and contamination wear/erosion. The purpose of this test is mainly to compare the sensitivity of different types of hydraulic valves to particle contaminants under the same test conditions. Since it is impossible to test all possible working conditions on site, the test results cannot be used as a basis for quantitatively evaluating the performance of hydraulic valves under actual contamination conditions on site.
Through this evaluation method, the effects of different particle sizes and contamination concentrations on hydraulic valve contamination jamming and contamination wear/erosion can be obtained, thereby determining the filtration requirements required to protect the hydraulic valve. This standard applies to all types of hydraulic valves using hydraulic oil (liquid) as the working medium. Reference standards
GB8104
GB8105
GB8106
GB/T14039
3 Definitions
3.1 Contamination sensitivity
Test method for flow control valves
Test method for pressure control valves
Test method for directional control valves
Hydraulic system working medium solid particle contamination level code The degree of change in valve performance caused by solid particle contaminants in the oil. 3.2 Contamination jamming
The phenomenon that contaminants trapped between two relatively moving surfaces (such as valve core-valve hole, valve core-valve sleeve assembly) hinder the relative movement of the two. 3.3 Contamination wear/erosion
Contamination wear or contamination erosion caused by solid particle contaminants in the valve leads to material abrasion. It includes abrasive wear caused by solid particle contaminants trapped between two relatively moving surfaces and erosion wear of the throttling edge by solid particle contaminants in the oil. 4 Test apparatus and test requirements
4.1 Test apparatus
4.1.1 The typical test circuit of the test apparatus is shown in Figure 1. It consists of an oil tank, a pump, a contaminant injection system, a heat exchanger, a flow meter, a pressure gauge, a thermometer and a filter. The components selected in the test circuit must have good working performance in contaminated oil. Approved by the Ministry of Machinery Industry on December 1, 1995
Implementation on July 1, 1996
JB/T78571995
1—Oil tank; 2—Pressure gauge; 3—Thermometer; 4—Pump; 5—Cooler; 6—Flow meter; 7—Sampling valve; 8—Shut-off valve: 9—Reversing valve; 10—Filter; 11—Differential pressure gauge; 12—Check valve; 13—Throttle valve; 14—Test valve; 15—Throttle valve; 16—Contaminant injector; 17—Shut-off valve; 18—Pressure gauge; 19—Pressure gauge; 20—Safety valve Figure 1 Typical test circuit for valve contamination sensitivity (taking directional valve as an example) The oil tank should be made into a conical bottom with a cone angle less than 90° to ensure sufficient stirring of the oil. 4.1.2
4.1.3The volume of the pollutant injector is about 500mL, the height to diameter ratio is about 10:1, and the cone angle of the cone bottom is less than 90°4.1.4
The heat exchanger shall not retain pollutants.
It is recommended to use a single-channel or dual-channel heat exchanger, installed vertically, with the oil entering from the bottom of the heat exchanger, and the oil flows in the tube, and the cooling water flows outside the tube.
The flow meter should be insensitive to pollutants, and the measurement accuracy should be within ±2% of the measured value. The filter should be able to make the system cleanliness reach the solid particle pollution level code 12/10 or higher. 4.1.7
One set of equipment for gravimetric determination of oil contamination, and one automatic particle counter. 4.1.8When the test valve has a pilot circuit, the pilot circuit should have the same pollution source as the other parts of the test valve. 4.2 Test oil
4.2.1 Use mineral oil with a kinematic viscosity of 28.8×10-6~35.2×10-m2/s at 40℃. Record the type, code, production unit and batch number of the oil.
4.2.2 The volume of the test system oil (L), excluding the filter circuit, is numerically equal to 1/4~1/2 of the test flow rate (L/min) of the tested valve, with an error range of ±10%. Record the oil volume. 2
The test system oil temperature is 40±2℃.
4.3 Test items
4.3.1AC fine test powder
JB/T 7857—1995
Use a qualified sifter to size the fine test powder. The mass percentage of the powder in each size segment to the mass percentage of the full size segment of 0~80um should be within the range specified in Table 1. Table 1
Test powder
Size segment μm
Carbonyl iron
Mass percentage of AC powder in each size segment in the mass of the whole size segmentAverage
Sieve the carbonyl iron with a qualified sifter, and the size segmentation shall meet the requirements of Table 2. Table 2
Sampling bottle
Maximum size μm
Mass Average size μm
The cleanliness level (RCL) of the sampling bottle shall be less than 10 particles larger than 10μm per mL of bottle volume. 4.3.4 Contaminated liquid injection bottle
The cleanliness level of the contaminated liquid injection bottle shall be less than 1000 particles larger than 10μm per mL of bottle volume4.4
Installation of the test system
The size of the pipes connecting the hydraulic components shall ensure that the oil in the test circuit is in a turbulent state. Take measures to prevent pollutants from being trapped and silted in the circuit to ensure that there is no air in the test system. Verification of the test device
Install the multi-channel pipe joint in the test circuit instead of the test valve, so that the oil passes through the test system and flushes all pipes. 5.2
Adjust the test flow rate to approximately the minimum test flow rate. 5.3Circulate the filter system oil until the system cleanliness reaches the solid particle pollution level code 12/10 or higher, operate the reversal reading 9, and bypass the filter.
Weigh the pollutant with a mass of 8: grams to make the pollution degree of the test system reach 250±10mg/L. 8Calculate according to the following formula:3
Where: g—pollutant mass, g;
X, pollution degree, g/L;
V—system oil volume, L.
JB/T78571995
g;=X,V
The pollutant used in the verification test is determined according to the pollutant used in the contamination clamping test. If the clamping test uses the pollutant of the A preparation scheme, the verification test uses the fine test powder of the full size segment. If the clamping test uses the pollutant of the B preparation scheme, the verification test uses a mixture of 0-40μm fine test powder and carbonyl iron with size code L (see Table 3). 5.6 Pour the pollutant slurry (see 5.5) into the injector. The slurry must be fully stirred and mixed to prevent the particles from agglomerating and caking.
5.7 Inject the pollutant slurry in the injector evenly and slowly into the system, and the injection time shall not be less than 5 minutes. 5.8 The operating time of the test system shall not be less than the time for each injected pollutant to circulate in the system during the contamination clamping test. The cycle time required for each working position of the test valve is about 60 minutes. 5.9 During the operation of the test system, take a sample from the system every 15 minutes, for a total of 4 samples. 5.10 Determine the contamination of each sample by weight. 5.11 If the error between the contamination of the four samples and the initial contamination is within the range given in Table 4, the test system can be considered qualified. 5.12 After the verification test is qualified, use the filter to filter the oil until the system cleanliness reaches the solid particle contamination level code 12/10 or higher.
5.13 When the oil tank or system pipeline is changed, the verification test should be repeated. 6 Contamination clamping test procedure
6.1 After the test system is verified, the test valve is installed in the test loop instead of the multi-channel pipe joint. According to the test requirements, install the necessary control devices and data recording devices. 6.2 According to the requirements of Tables 3 and 4, weigh 8 grams of each test contaminant of various sizes, stir into slurry and put it into each clean contaminated liquid injection bottle.
6.3 Raise the system pressure to the specified value, and quickly measure and record the evaluation parameters of the valve in clean oil after the valve has operated several times. This value will serve as the basic data for the evaluation parameters (see Chapter 9 for evaluation parameters). 6.4 Inject the pollutant slurry of the first size range evenly and slowly into the system. The injection time shall not be less than 5 minutes6.5 Cycle the test valve for at least 5 cycles to distribute the contaminated oil throughout the valve. 6.6 Set the test valve to the position or state most sensitive to contamination and hold it still for 30 seconds, and then measure the valve assessment parameters. Then, repeat the above operation at rest times of 1, 2, 4, 8, 16, and 32 minutes. Rest times cannot be accumulated. Before adding contaminants of different sizes or concentrations next time, the oil in the system must be re-filtered (see 5.2 and 5.3). 6.7 Repeat 6.4 to 6.6 until all contaminants of the required size are injected and the test is completed. Note: The injection order of contaminants of different sizes in the contamination and hold test is determined by the tester. 7 Contamination Wear/Erosion Test Procedure
7.1 After the test system is verified to be qualified, install the test valve in the test loop instead of the multi-channel pipe joint. Install the necessary control devices and data recording devices according to the test requirements. 7.2 According to the requirements of Table 3 and Table 4, weigh each g of the test pollutants of various sizes, stir them into slurry, and then put them into each clean pollutant injection bottle.
JB/T7857-1995
7.3 Raise the system test pressure to the specified value and record the evaluation parameters of the valve in clean oil. Note: If a certain test valve is to undergo both contamination wear/erosion test and contamination clamping test, all contamination clamping tests must be completed before starting the contamination wear test
7.4 Slowly inject the contaminant slurry of the first size range into the system evenly, and the injection time shall not be less than 5 minutes. 7.5 The test valve is cycled at the specified frequency for 30 minutes at the rated flow and pressure. If not specified, the minimum cycle frequency is as follows: Servo valve
Electric valve
30 times/min
12 times/minbzxZ.net
Non-electric valve5 times/min
Note: If the valve sticks during the cycle action, it is recommended to terminate the test and re-test at a lower contamination level. 7.6 Stop the cycle action of the valve. Operate the reversing valve 9, connect the filter circuit, and make the system cleanliness reach the solid particle contamination level code 12/10 or higher through cyclic filtration.
7.7 Measure the evaluation parameters of the valve. Unless otherwise specified, the test should be terminated when the leakage exceeds the specified maximum value or the dynamic performance exceeds its specified value.
7.8 Repeat the contents of 7.4 to 7.7 using larger size segments of contaminants until all size segments of contaminants are tested or the valve leakage exceeds its maximum specified value.
Note: The contamination wear/erosion test must be carried out in strict order from small to large contaminant size. 8 Selection of test contaminants and concentrations
8.1 Selection of contaminants for contamination seizure test
Table 3 lists two contaminant preparation schemes for contamination seizure test. The contaminant of scheme A is sieved fine test powder. When the magnetism of the contaminant is not considered, it is recommended to use scheme A for testing. Non-electric hydraulic valves usually fall into this category. Scheme B is a mixture of fine test powder and carbonyl iron, in which the contaminant with an upper cut size of less than 40μm is a mixture of fine test powder and magnesium-based iron, and the contaminant of 0-80μm is the same as that in scheme A. The contaminant of scheme B should be used for the contamination seizure test of electric valves. Table 3
Contaminant composition and size range
Fine test powder (FTD) μm
8.2 Selection of contamination degree for contamination clamping test
Carbonyl iron (CL)
Test powder preparation scheme
50%FTD+50%CL
100%FTD
100%FTD
Contamination degree Xmg/L
Error mg/L
JB/T78571995
Occasions for valve use
A small amount of contaminant intrusion, the system has a strong filtering ability. A quantitative amount of contaminant intrusion, the system has a certain filtering ability. A large amount of contaminant intrusion, the system has almost no filtering ability. Table 4 lists three contamination degrees for contamination test, which are 10, 50, and 250 mg/L respectively. When selecting the contamination degree for contamination clamping test, the contaminant intrusion rate and the filtering performance of the system should be considered. The test contamination level should not be less than the maximum contamination level that may occur. The maximum contamination level may occur when the component fails or maintenance is neglected. 8.3 Contamination Wear/Erosion Test Contaminants
The contaminants used in the contamination wear/erosion test are the sieved fine test powders listed in Table 1. 8.4 Selection of Contamination Levels for Contamination Wear/Erosion Tests Table 4 lists three contamination levels for contamination tests, which are 10, 50, and 250 mL respectively. The selection of contamination level for contamination wear/erosion tests depends on the purpose of the test and the desire to reduce the time and cost of the test. The purposes of the wear/erosion test are as follows: a. Compare the wear performance of different valves;
b. Determine the filtration requirements required for use; meet or improve a certain technical requirement.
When comparing the wear performance of different valves and determining the filtration requirements, it is advisable to conduct the test at a high concentration. If a certain technical requirement is to be met, it is necessary to start from a low concentration and continuously increase the concentration until the valve performance decreases. 2
Valve contamination sensitivity assessment parameters
Valve contamination sensitivity assessment parameters are specified in Table 5. The test method shall be in accordance with GB8104, GB8105, GB8106 and other relevant standards.
Test type
Evaluation parameters
Check valve
Directional control valve
Pressure control valve
Flow control valve
Servo valve, proportional valve
Test report
Manual, mechanical
Electro-hydraulic, electromagnetic
Clamping test
Valve core moving force
Pilot pressure
Current or voltage
Transient response characteristics
Transient characteristics
Wear/erosion test
Leakage
Internal leakage
Steady-state pressure-flow characteristics and transient response characteristics Steady-state characteristics and transient characteristics
Internal leakage
The valve model, test oil, temperature and pressure must be indicated in the test report. When evaluating the contaminated clamping performance, all the evaluation parameters measured under the initial clean oil and the contaminated oil must be given. When evaluating the wear/erosion performance, the evaluation parameters measured before and after each contamination cycle must be recorded. For the contaminated wear leakage test of each particle size segment, the pressure, leakage path, leakage volume and oil temperature must be recorded in the form of a table.
Additional Notes:
This standard was proposed by the National Hydraulic and Pneumatic Standardization Technical Committee and is under the jurisdiction of the Beijing Institute of Automation of the Machinery Industry of the Ministry of Machinery Industry. This standard was drafted by the Beijing Graduate School of China University of Mining and Technology. The main drafters of this standard are Li Fangjun, Xia Zhixin, Zhou Shiyu and Zhou Zheng. 7
People's Republic of China
Mechanical Industry Standard
Evaluation Method of Hydraulic Valve Contamination Sensitivity
JB/T78571995
Published and issued by the Mechanical Science Research Institute
Printed by the Mechanical Science Research Institute
(No. 2 Shouti South Road, Beijing
Format 880×1230
Postal Code 100044)
Sheet 5/8
Word Count 12.000
First Edition in May 1996
First Printing in May 1996
Price 8.00 Yuan
Print Quantity 1-500
Mechanical Industry Standard Service Network: http://www.JB.ac.cn661_83 Raise the system test pressure to the specified value and record the valve assessment parameters in clean oil. Note: If a test valve is to undergo both contamination wear/erosion test and contamination seizure test, all contamination seizure tests must be completed before starting the contamination wear test
7.4 Slowly and evenly inject the contamination slurry of the first size range into the system. The injection time shall not be less than 5 minutes. 7.5 The test valve is cycled at the specified frequency for 30 minutes at the rated flow and pressure. When not specified, the minimum cycle frequency is as follows: Servo valve
Electric valve
30 times/min
12 times/min
Non-electric valve5 times/min
Note: If the valve sticks during the cycle, it is recommended to terminate the test and re-test at a lower contamination level. 7.6 Stop the valve from cycling. Operate the reversing valve 9, connect the filter circuit, and make the system clean to the solid particle pollution level code 12/10 or higher through circulating filtration.
7.7 Measure the evaluation parameters of the valve. Unless otherwise specified, the test should be terminated when the leakage exceeds the specified maximum value or the dynamic performance exceeds its specified value.
7.8 Repeat the contents of 7.4 to 7.7 using pollutants of larger size segments until the pollutant tests of all size segments are completed or the valve leakage exceeds its maximum specified value.
Note: The pollution wear/erosion test must be carried out in strict accordance with the order of pollutant size from small to large. 8 Selection of test pollutants and concentrations
8.1 Selection of pollutants for pollution clamping test
Table 3 lists two pollutant preparation schemes for pollution clamping test. The pollutant of scheme A is sieved fine test powder. When the magnetism of the pollutant is not considered, it is recommended to use scheme A for testing. Non-electric hydraulic valves usually belong to this situation. Scheme B is a mixture of fine test powder and carbonyl iron, wherein the contaminant with an upper cut size less than 40 μm is a mixture of fine test powder and magnesium-based iron, and the contaminant of 0-80 μm is the same as that in Scheme A. The contamination clamping test of the electric valve should use the contaminant of Scheme B. Table 3
Contaminant composition and size range
Fine test powder (FTD) μm
8.2 Selection of contamination degree for contamination clamping test
Carbonyl iron (CL)
Test powder preparation scheme
50%FTD+50%CL
100%FTD
100%FTD
Contamination degree Xmg/L
Error mg/L
JB/T78571995
Occasions for valve use
A small amount of contaminant intrusion, the system has a strong filtering ability. A quantitative amount of contaminant intrusion, the system has a certain filtering ability. A large amount of contaminant intrusion, the system has almost no filtering ability. Table 4 lists three contamination degrees for contamination test, which are 10, 50, and 250 mg/L respectively. When selecting the contamination degree for contamination clamping test, the contaminant intrusion rate and the filtering performance of the system should be considered. The test contamination level should not be less than the maximum contamination level that may occur. The maximum contamination level may occur when the component fails or maintenance is neglected. 8.3 Contamination Wear/Erosion Test Contaminants
The contaminants used in the contamination wear/erosion test are the sieved fine test powders listed in Table 1. 8.4 Selection of Contamination Levels for Contamination Wear/Erosion Tests Table 4 lists three contamination levels for contamination tests, which are 10, 50, and 250 mL respectively. The selection of contamination level for contamination wear/erosion tests depends on the purpose of the test and the desire to reduce the time and cost of the test. The purposes of the wear/erosion test are as follows: a. Compare the wear performance of different valves;
b. Determine the filtration requirements required for use; meet or improve a certain technical requirement.
When comparing the wear performance of different valves and determining the filtration requirements, it is advisable to conduct the test at a high concentration. If a certain technical requirement is to be met, it is necessary to start from a low concentration and continuously increase the concentration until the valve performance decreases. 2
Valve contamination sensitivity assessment parameters
Valve contamination sensitivity assessment parameters are specified in Table 5. The test method shall be in accordance with GB8104, GB8105, GB8106 and other relevant standards.
Test type
Evaluation parameters
Check valve
Directional control valve
Pressure control valve
Flow control valve
Servo valve, proportional valve
Test report
Manual, mechanical
Electro-hydraulic, electromagnetic
Clamping test
Valve core moving force
Pilot pressure
Current or voltage
Transient response characteristics
Transient characteristics
Wear/erosion test
Leakage
Internal leakage
Steady-state pressure-flow characteristics and transient response characteristics Steady-state characteristics and transient characteristics
Internal leakage
The valve model, test oil, temperature and pressure must be indicated in the test report. When evaluating the contaminated clamping performance, all the evaluation parameters measured under the initial clean oil and the contaminated oil must be given. When evaluating the wear/erosion performance, the evaluation parameters measured before and after each contamination cycle must be recorded. For the contaminated wear leakage test of each particle size segment, the pressure, leakage path, leakage volume and oil temperature must be recorded in the form of a table.
Additional Notes:
This standard was proposed by the National Hydraulic and Pneumatic Standardization Technical Committee and is under the jurisdiction of the Beijing Institute of Automation of the Machinery Industry of the Ministry of Machinery Industry. This standard was drafted by the Beijing Graduate School of China University of Mining and Technology. The main drafters of this standard are Li Fangjun, Xia Zhixin, Zhou Shiyu and Zhou Zheng. 7
People's Republic of China
Mechanical Industry Standard
Evaluation Method of Hydraulic Valve Contamination Sensitivity
JB/T78571995
Published and issued by the Mechanical Science Research Institute
Printed by the Mechanical Science Research Institute
(No. 2 Shouti South Road, Beijing
Format 880×1230
Postal Code 100044)
Sheet 5/8
Word Count 12.000
First Edition in May 1996
First Printing in May 1996
Price 8.00 Yuan
Print Quantity 1-500
Mechanical Industry Standard Service Network: http://www.JB.ac.cn661_83 Raise the system test pressure to the specified value and record the valve assessment parameters in clean oil. Note: If a test valve is to undergo both contamination wear/erosion test and contamination seizure test, all contamination seizure tests must be completed before starting the contamination wear test
7.4 Slowly and evenly inject the contamination slurry of the first size range into the system. The injection time shall not be less than 5 minutes. 7.5 The test valve is cycled at the specified frequency for 30 minutes at the rated flow and pressure. When not specified, the minimum cycle frequency is as follows: Servo valve
Electric valve
30 times/min
12 times/min
Non-electric valve5 times/min
Note: If the valve sticks during the cycle, it is recommended to terminate the test and re-test at a lower contamination level. 7.6 Stop the valve from cycling. Operate the reversing valve 9, connect the filter circuit, and make the system clean to the solid particle pollution level code 12/10 or higher through circulating filtration.
7.7 Measure the evaluation parameters of the valve. Unless otherwise specified, the test should be terminated when the leakage exceeds the specified maximum value or the dynamic performance exceeds its specified value.
7.8 Repeat the contents of 7.4 to 7.7 using pollutants of larger size segments until the pollutant tests of all size segments are completed or the valve leakage exceeds its maximum specified value.
Note: The pollution wear/erosion test must be carried out in strict accordance with the order of pollutant size from small to large. 8 Selection of test pollutants and concentrations
8.1 Selection of pollutants for pollution clamping test
Table 3 lists two pollutant preparation schemes for pollution clamping test. The pollutant of scheme A is sieved fine test powder. When the magnetism of the pollutant is not considered, it is recommended to use scheme A for testing. Non-electric hydraulic valves usually belong to this situation. Scheme B is a mixture of fine test powder and carbonyl iron, wherein the contaminant with an upper cut size less than 40 μm is a mixture of fine test powder and magnesium-based iron, and the contaminant of 0-80 μm is the same as that in Scheme A. The contamination clamping test of the electric valve should use the contaminant of Scheme B. Table 3
Contaminant composition and size range
Fine test powder (FTD) μm
8.2 Selection of contamination degree for contamination clamping test
Carbonyl iron (CL)
Test powder preparation scheme
50%FTD+50%CL
100%FTD
100%FTD
Contamination degree Xmg/L
Error mg/L
JB/T78571995
Occasions for valve use
A small amount of contaminant intrusion, the system has a strong filtering ability. A quantitative amount of contaminant intrusion, the system has a certain filtering ability. A large amount of contaminant intrusion, the system has almost no filtering ability. Table 4 lists three contamination degrees for contamination test, which are 10, 50, and 250 mg/L respectively. When selecting the contamination degree for contamination clamping test, the contaminant intrusion rate and the filtering performance of the system should be considered. The test contamination level should not be less than the maximum contamination level that may occur. The maximum contamination level may occur when the component fails or maintenance is neglected. 8.3 Contamination Wear/Erosion Test Contaminants
The contaminants used in the contamination wear/erosion test are the sieved fine test powders listed in Table 1. 8.4 Selection of Contamination Levels for Contamination Wear/Erosion Tests Table 4 lists three contamination levels for contamination tests, which are 10, 50, and 250 mL respectively. The selection of contamination level for contamination wear/erosion tests depends on the purpose of the test and the desire to reduce the time and cost of the test. The purposes of the wear/erosion test are as follows: a. Compare the wear performance of different valves;
b. Determine the filtration requirements required for use; meet or improve a certain technical requirement.
When comparing the wear performance of different valves and determining the filtration requirements, it is advisable to conduct the test at a high concentration. If a certain technical requirement is to be met, it is necessary to start from a low concentration and continuously increase the concentration until the valve performance decreases. 2
Valve contamination sensitivity assessment parameters
Valve contamination sensitivity assessment parameters are specified in Table 5. The test method shall be in accordance with GB8104, GB8105, GB8106 and other relevant standards.
Test type
Evaluation parameters
Check valve
Directional control valve
Pressure control valve
Flow control valve
Servo valve, proportional valve
Test report
Manual, mechanical
Electro-hydraulic, electromagnetic
Clamping test
Valve core moving force
Pilot pressure
Current or voltage
Transient response characteristics
Transient characteristics
Wear/erosion test
Leakage
Internal leakage
Steady-state pressure-flow characteristics and transient response characteristics Steady-state characteristics and transient characteristics
Internal leakage
The valve model, test oil, temperature and pressure must be indicated in the test report. When evaluating the contaminated clamping performance, all the evaluation parameters measured under the initial clean oil and the contaminated oil must be given. When evaluating the wear/erosion performance, the evaluation parameters measured before and after each contamination cycle must be recorded. For the contaminated wear leakage test of each particle size segment, the pressure, leakage path, leakage volume and oil temperature must be recorded in the form of a table.
Additional Notes:
This standard was proposed by the National Hydraulic and Pneumatic Standardization Technical Committee and is under the jurisdiction of the Beijing Institute of Automation of the Machinery Industry of the Ministry of Machinery Industry. This standard was drafted by the Beijing Graduate School of China University of Mining and Technology. The main drafters of this standard are Li Fangjun, Xia Zhixin, Zhou Shiyu and Zhou Zheng. 7
People's Republic of China
Mechanical Industry Standard
Evaluation Method of Hydraulic Valve Contamination Sensitivity
JB/T78571995
Published and issued by the Mechanical Science Research Institute
Printed by the Mechanical Science Research Institute
(No. 2 Shouti South Road, Beijing
Format 880×1230
Postal Code 100044)
Sheet 5/8
Word Count 12.000
First Edition in May 1996
First Printing in May 1996
Price 8.00 Yuan
Print Quantity 1-500
Mechanical Industry Standard Service Network: http://www.JB.ac.cn661_8L)
Test powder preparation scheme
50%FTD+50%CL
100%FTD
100%FTD
Contamination Xmg/L
Error mg/L
JB/T78571995
Valve application occasions
A small amount of pollutants infiltrate, the system has a strong filtering ability. A certain amount of pollutants infiltrate, the system has a certain filtering ability. A large amount of pollutants infiltrate, the system has almost no filtering ability. Table 4 lists three contamination levels for contamination tests, which are 10, 50, and 250 mg/L respectively. The contamination rate of contamination clamping test and the filtering performance of the system should be considered when selecting the contamination level. The test contamination level should not be less than the maximum contamination level that may occur. The maximum contamination level may occur when the component fails or maintenance is neglected. 8.3 Contamination wear/erosion test contaminants
The contaminants used in the contamination wear/erosion test are the sieved fine test powders listed in Table 1. 8.4 Selection of contamination degree for contamination wear/erosion test Table 4 lists three contamination degrees for contamination test, which are 10, 50, and 250 mL respectively. The selection of contamination degree for contamination wear/erosion test depends on the purpose of the test and the desire to reduce the test time and cost. The purposes of wear/erosion test are as follows: a. Comparing the wear performance of different valves; b. Determining the filtration requirements required for use; meeting or improving certain technical requirements. When comparing the wear performance of different valves and determining the filtration requirements, it is advisable to conduct the test at a high concentration. If a certain technical requirement is to be met, it is necessary to start from a low concentration and continuously increase the concentration until the performance of the valve decreases. 2
Valve contamination sensitivity assessment parameters
Valve contamination sensitivity assessment parameters are specified in Table 5. The test method is in accordance with GB8104, GB8105, GB8106 and other relevant standards.
Test type
Evaluation parameters
Check valve
Directional control valve
Pressure control valve
Flow control valve
Servo valve, proportional valve
Test report
Manual, mechanical
Electro-hydraulic, electromagnetic
Clamping test
Valve core moving force
Pilot pressure
Current or voltage
Transient response characteristics
Transient characteristics
Wear/erosion test
Leakage
Internal leakage
Steady-state pressure-flow characteristics and transient response characteristics Steady-state characteristics and transient characteristics
Internal leakage
The valve model, test oil, temperature and pressure must be indicated in the test report. When evaluating the contaminated clamping performance, all the evaluation parameters measured under the initial clean oil and the contaminated oil must be given. When evaluating the wear/erosion performance, the evaluation parameters measured before and after each contamination cycle must be recorded. For the contaminated wear leakage test of each particle size segment, the pressure, leakage path, leakage volume and oil temperature must be recorded in the form of a table.
Additional Notes:
This standard was proposed by the National Hydraulic and Pneumatic Standardization Technical Committee and is under the jurisdiction of the Beijing Institute of Automation of the Machinery Industry of the Ministry of Machinery Industry. This standard was drafted by the Beijing Graduate School of China University of Mining and Technology. The main drafters of this standard are Li Fangjun, Xia Zhixin, Zhou Shiyu and Zhou Zheng. 7
People's Republic of China
Mechanical Industry Standard
Evaluation Method of Hydraulic Valve Contamination Sensitivity
JB/T78571995
Published and issued by the Mechanical Science Research Institute
Printed by the Mechanical Science Research Institute
(No. 2 Shouti South Road, Beijing
Format 880×1230
Postal Code 100044)
Sheet 5/8
Word Count 12.000
First Edition in May 1996
First Printing in May 1996
Price 8.00 Yuan
Print Quantity 1-500
Mechanical Industry Standard Service Network: http://www.JB.ac.cn661_8L)
Test powder preparation scheme
50%FTD+50%CL
100%FTD
100%FTD
Contamination Xmg/L
Error mg/L
JB/T78571995
Valve application occasions
A small amount of pollutants infiltrate, the system has a strong filtering ability. A certain amount of pollutants infiltrate, the system has a certain filtering ability. A large amount of pollutants infiltrate, the system has almost no filtering ability. Table 4 lists three contamination levels for contamination tests, which are 10, 50, and 250 mg/L respectively. The contamination rate of contamination clamping test and the filtering performance of the system should be considered when selecting the contamination level. The test contamination level should not be less than the maximum contamination level that may occur. The maximum contamination level may occur when the component fails or maintenance is neglected. 8.3 Contamination wear/erosion test contaminants
The contaminants used in the contamination wear/erosion test are the sieved fine test powders listed in Table 1. 8.4 Selection of contamination degree for contamination wear/erosion test Table 4 lists three contamination degrees for contamination test, which are 10, 50, and 250 mL respectively. The selection of contamination degree for contamination wear/erosion test depends on the purpose of the test and the desire to reduce the test time and cost. The purposes of wear/erosion test are as follows: a. Comparing the wear performance of different valves; b. Determining the filtration requirements required for use; meeting or improving certain technical requirements. When comparing the wear performance of different valves and determining the filtration requirements, it is advisable to conduct the test at a high concentration. If a certain technical requirement is to be met, it is necessary to start from a low concentration and continuously increase the concentration until the performance of the valve decreases. 2
Valve contamination sensitivity assessment parameters
Valve contamination sensitivity assessment parameters are specified in Table 5. The test method is in accordance with GB8104, GB8105, GB8106 and other relevant standards.
Test type
Evaluation parameters
Check valve
Directional control valve
Pressure control valve
Flow control valve
Servo valve, proportional valve
Test report
Manual, mechanical
Electro-hydraulic, electromagnetic
Clamping test
Valve core moving force
Pilot pressure
Current or voltage
Transient response characteristics
Transient characteristics
Wear/erosion test
Leakage
Internal leakage
Steady-state pressure-flow characteristics and transient response characteristics Steady-state characteristics and transient characteristics
Internal leakage
The valve model, test oil, temperature and pressure must be indicated in the test report. When evaluating the contaminated clamping performance, all the evaluation parameters measured under the initial clean oil and the contaminated oil must be given. When evaluating the wear/erosion performance, the evaluation parameters measured before and after each contamination cycle must be recorded. For the contaminated wear leakage test of each particle size segment, the pressure, leakage path, leakage volume and oil temperature must be recorded in the form of a table.
Additional Notes:
This standard was proposed by the National Hydraulic and Pneumatic Standardization Technical Committee and is under the jurisdiction of the Beijing Institute of Automation of the Machinery Industry of the Ministry of Machinery Industry. This standard was drafted by the Beijing Graduate School of China University of Mining and Technology. The main drafters of this standard are Li Fangjun, Xia Zhixin, Zhou Shiyu and Zhou Zheng. 7
People's Republic of China
Mechanical Industry Standard
Evaluation Method of Hydraulic Valve Contamination Sensitivity
JB/T78571995
Published and issued by the Mechanical Science Research Institute
Printed by the Mechanical Science Research Institute
(No. 2 Shouti South Road, Beijing
Format 880×1230
Postal Code 100044)
Sheet 5/8
Word Count 12.000
First Edition in May 1996
First Printing in May 1996
Price 8.00 Yuan
Print Quantity 1-500
Mechanical Industry Standard Service Network: http://www.JB.ac.cn661_8
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