JB/T 51127-1999 Reliability assessment of small and medium power diesel products
Some standard content:
Mechanical Industry Standard of the People's Republic of China
JB/T51127—1999
Small and medium power diesel engines
Product reliability assessment
(internal use)
Published on December 30, 1999
National Bureau of Machinery Industry
Implementation on June 1, 2000
JHIT51127-[999
2Introduction to Bar Standard
3Evaluation method
4Bench test force
S Failure rate classification and judgment rules
Appendix A! Appendix (indicative appendix) Distribution quantile table Appendix (indicative appendix) Reliability test sample table
Alarm record C (indicative appendix) Engine continental test equipment, instrument list. Yin record D (vibration record) Starting performance test result summary table Appendix E (indicative appendix) Failure drop record table of reliability test record F (standard record) Failure mode classification table of diesel engine with power/power 12
JBrF5112*-199y
Compared with the original standard of 19T5t127.1-51127.3-94 small and medium-power diesel engines, the main technical content changes are as follows: 1. Remove the reinforcement coefficient A in the calculation formula; 2. Add the sample frame bearing belt test risk interval: modify the fault classification of some failure modes. The whole design of product reliability assessment, this standard and Appendix A of this standard. Appendix D, Appendix C, Appendix D and Record R are all informative appendices. Appendix E of this standard is a standard appendix.
This standard is proposed and organized by the National Technical Committee for Standardization of Internal Combustion Engines. ? This standard was initiated by: Erhai Internal Combustion Engine Research Institute, Shanghai Diesel Engine Co., Ltd., and the main drafters of this standard are: De Junshou, Lu Yifei, Jiang Liqing. This standard was issued in 1990 as JB/NQ207.J-207.3-90, and the standard number was adjusted in September 1994 to JB.T51127.151127.394.
1 Scope
Mechanical Industry Standards of the People's Republic of China
Small and Medium Power Diesel Engines
Product Reliability Assessment
(Internal Use)
JB/T 51127-1999
Replaces JB/T51127[-5]127.3—4
Not specified in this standard. It specifies the compatibility test and evaluation method, bench test method, fault classification and identification of small power diesel engines. This standard is applicable to the compatibility test and evaluation of small and medium power diesel engines (hereinafter referred to as "diesel engines") produced in ten batches. 2 Referenced standards
5 The provisions contained in the engraved standard are all the provisions of this standard through reference in this standard. When this standard is published, the versions shown are all valid. All standards will be revised: Parties using this standard should explore the possibility of using the new versions of the following standards: GR.T1105.1—1987
GB/T 1105.3:1987
JB.T 97731—1999
JB:T $1104—1999
3 Assessment method
3.1 Reliability assessment index
Internal combustion engine bench performance test standard environmental conditions and power, fuel consumption and oil consumption standard calibration
Internal combustion engine bench performance test method is a technical purple hysteresis engine bench test assessment method
Quality classification of small and medium-sized diesel engines
3.1.1 Average T working time before failure (MTTFF) Average working time before first failure is the average value of the product of the first failure of the diesel engine out of specification (h:) point estimate value is:
Wu Zhong: ——Number of test samples:
Number of units with first failure (excluding minor failures): +fn-rl|| tt||The cumulative working time of the first sample before the first failure, h; the cumulative working time of the first sample without failure during the test period (including the running-in and performance test period), hT-timing test time, h,
Note: When the MTTFF value of the product is calculated by the product of the test time and the number of test samples: b] The lower limit of the one-sided confidence interval of the average working time before the first failure with a confidence level of [1 time] is: Approved by the State Machinery Industry on December 30, 1999
Implementation on June 1, 2010
Where: e
(MTTEF
Risk coefficient or visibility level:
JB/T SIE27-1999
(2,2r+2#
Confidence level is (1-), and the degree () is the distribution quantile of 2+2. It can be obtained from the distribution quantile table in the attached requirement (the attached requirement provided). 3.1.2 Interval time for fault relief MTRF
The half-mean fault interval is the average working time between two equal faults, h,) and the calculated value is:
Where: . is the operating time of the first prototype, hnr
The total number of prototype faults (excluding minor faults) during the test period (including the integration and performance test period), Note: It is still negative! When the flow rate is 10, the MTBF value of the product is calculated by multiplying the number of testable machines at the time of test monitoring truncation. b) The lower limit of the single-measurement confidence interval of the mean failure interval with a confidence level of (1-) is estimated as follows: (MTBF), -
3.1.3 Comprehensive score of no-failure performance 9
The comprehensive score of no-failure performance is a comprehensive evaluation index of the product's no-failure performance. +2
During the test, if a sample fails to meet the requirements, the comprehensive score of no-failure performance of the product will fail and will not be calculated. When no service failure occurs, the comprehensive score of no-failure performance is calculated by formula (5): (MTBFL(KE)
9=100-
Where: [MIHF]—MTBF target value of diesel engine product specification, J: 7, the total number of various types of failures that occurred on the sample during the test period (including the running-in performance test period); the longest! Fault hazard coefficient of each fault. Fault hazard coefficients of various types of faults are as follows: Severe fault: K,=60
General fault: K,=20
Mild fault: Weak fault: 5
Time coefficient of one fault:
JE/T51127-1999
Where: T--the cumulative working time of the sample when the first fault occurs, h. Note: When counting the second time, it is counted as zero: when =0, 2=03. 1.4 Mean Time to Repair MTTH
Mean Time to Repair refers to the average value of the time between failures (excluding minor failures) of a product under specified conditions of use within a certain period of time, excluding the time for maintenance and planned repairs specified in the product manual. MTER=
Formula: 1. The time required for the first failure, including the sum of the time for fault diagnosis, repair implementation and debugging, 2. 3.1.5 Validity Validity refers to the time that a product can maintain its specified functions within a certain period of time, formula: (8) Calculation: MTBF
MTBF-MTTR
3.1.6 B50 life
B50 overhaul life refers to the life of the product under the specified conditions of use until 50% of the products reach the overhaul state, calculated by the total number of hours actually used. For timing, the actual usage hours of the prototypes when they reach the overhaul state are arranged in ascending order. When the number of prototypes () is the number of prototypes, the actual usage hours of the second prototype is the B0 overhaul life of the product. When the number of prototypes () is the number of prototypes: then the m/2 The arithmetic mean of the actual use efficiency of the first and second (2-1) prototypes is the B50 overhaul life of the product. The overhaul state is the state where the engine performance drops to a certain limit value and the engine performance is damaged to its limit value in certain climate conditions. The engine manufacturer's regulations on durability are as follows. 3.2 Reliability test The reliability assessment of diesel engine products is carried out through three aspects: bench reliability test, on-site reliability test and user survey. 3.2. Bench reliability test 3.1.1.1 The bench reliability test is carried out in accordance with the provisions of Chapter 4 . 3.21.2 The assessment indicators are the mean time to failure (MTTFF), mean time between failures (MTBF) and comprehensive reliability score (other).
3.1.2 On-site reliability test
3.2.2.1 The on-site reliability test is carried out under the supervision of a dedicated person in the actual use of the product. 3.2.2.2 Before the test, a field reliability test outline should be formulated and the test results should be written, and the user should provide proof. 3.2.2.3 During the test, any failure of the diesel engine must be reported with a fault analysis and improvement measures. 3.2.2.4 The assessment criteria are the average working time before the first failure (MTTFF) and the average time between failures [MTBF], the average time to repair (MTTR), effectiveness (A) and B50 overhaul life and other indicators to accumulate data, 3.1.3 User survey
JR/F51127-1999
3.2.3.1 User survey If the actual reliability of the diesel engine in use is adjusted, the card failure mode that occurs during use is cleared, and the average working time before the first failure of the product in use is counted. 3.2.3.2 After the user survey, the user survey report is written down. 3.3 Failure determination
Each failure period that occurs in the reliability test should be judged one by one according to the provisions of Chapter 5. 3.4 Reliability assessment
3.4.! After the diesel engine product is assessed according to 3.2, the specific evaluation indicators of each assessment index shall be calculated according to the calculation formula in 3.1 and the product reliability assessment report shall be written.
3.4.2 When the reliability assessment indicators of the product have reached the specified standard, the reliability level of the product shall be evaluated. If any of the assessment indicators does not reach the specified standard, the reliability assessment of the product shall be unqualified. 3.4.3 The reliability index classification of diesel engine products shall be in accordance with the provisions of 18T51104. 4 Self-test method
4.1 Test sample
4.1.1 Sample
4.1.1.1 The sampled machine shall be a qualified product of the factory inspection department and meet the requirements of the product drawings and relevant technical standards. 4.1.1.2 The test sample must be equipped with all accessories specified in the product technical requirements. When sampling, the assembly completeness and appearance quality of the sample shall be checked according to the random technical documents and RT51104. 4.1.2 Sampling method
Random sampling is adopted.
4.1.3 Sample matrix
The sample shall be drawn at the end of the production line of the manufacturer, and it can also be drawn on the production line of the supporting factory if necessary. When sampling in the production plant, the sample shall not be less than 26 units in the section. When sampling in the supporting factory, the sample matrix shall not be subject to the setting. The diesel engine of the fire type that is produced according to the sales volume. If necessary, it is allowed to conduct sampling inspection twice.
4.1.4 Number of samples
Total units. Among them, "a spare sample machine is used in case of failure to reach the test sequence due to non-machine problems. After removal, no additional test or replacement of parts shall be carried out. 4.2 Test conditions
4.2.1 The test shall be carried out under the standard environmental conditions specified in GBT1105.1 as much as possible. When the test environmental conditions do not conform to the standard environmental conditions, the power and fuel consumption rate shall be corrected in accordance with GBT1150.1. 4.2.2 Test equipment, instrument accuracy, measurement position and method shall conform to GBT1150.3. 4.2.3 The fuel, engine oil and coolant composition used for the test shall conform to the provisions of the product manual. The fuel quality composition of the engine shall conform to the relevant petroleum product standards of Taiwan. The engine and cooling filter temperature and exhaust gas composition shall conform to the provisions of JB/T511. 4.3 Test items and methods
4.3.1 Starting test
The product method shall be in accordance with JB51104. |The prototype is started at room temperature and the test is repeated for 2 minutes each time. 4.3.2 Preheating station cross-combination test
JET51127—1999
A diesel engine with a rated power of 5mn is allowed to be run-in according to the integrated specifications provided by the diesel engine manufacturer, but the time shall not exceed 45h. The diesel engine with rated power shall be run-in according to the JB/T51104 specification. 4.3.3 Performance test
4.3 .3.1 Test items 1) Rated power check 2) Special tests specified for safety purposes: 3) Rated power test for diesel engines for tractors, automobiles, two-stage machinery and combined machines 4) Rated power test for marine main engines 5) Rated speed test for marine main engines 6) Rated speed test for marine main engines 7) Rated speed test for marine main engines 8) Rated speed test for marine main engines 9) Rated speed test for marine main engines 10) Rated speed test for marine main engines 11) Rated speed test for marine main engines 12) Rated speed test for marine main engines 13) Rated speed test for marine main engines 14) Rated speed test for marine main engines 15) Rated speed test for marine main engines 16) Rated speed test for marine main engines 17) Rated speed test for marine main engines 18) Rated speed test for marine main engines 19) Rated speed test for marine main engines 20) Rated speed test for marine main engines 21) Rated speed test for marine main engines 22) Rated speed test for marine main engines 23) Rated speed test for marine main engines 24) Rated speed test for marine main engines 25) Rated speed test for marine main engines 26) Rated speed test for marine main engines 27) Rated speed test for marine main engines 28) Rated speed test for marine main engines 29) Rated speed test for marine main engines 30) Rated speed test for marine main engines 31) Rated speed test for marine main engines 32) Rated power test for marine main engines 33) Rated speed test for marine main engines 34) Rated speed test for marine main engines 35) Rated speed test for marine main engines 36) Rated speed test for marine main engines 37) Rated speed test for marine main engines 38) Rated speed test for marine main engines 39) Rated speed test for marine main engines 40) Rated speed test for marine main engines 41) Rated speed test for marine main engines 42) Rated speed test for marine main engines 4H belt test
4.3.4.1 Test duration
Each hour
4.3.4.1 Test specification
Based on the rated power of the same, the test is carried out according to the provisions of Table 1 to Table 4. The overload time of each test shall not exceed 2min. Table 1 Test speed calibrated at 15min speed
Test speed
Maximum no-load rated transfer
Micro-torque Point stop
Stack low no-load total rated speed
Calibration Langdi
With the number of stable speed
Calibration information
Maximum
Calibration condition torque short
#/T51127-1999
2100 1h power calibration diesel engine
Minimum no-load rated speed
[D5% rated speed
Sufficient high research to offer stable start
Large cabinet Point transfer accuracy
Minimum research after activity
1D5% standard constant speed
Quantity low altitude caused by fixed transfer
Calibration 1 Initial protection
Most people twist
Calibration 1. Condition twist ground
Table 3 Modify 12h power calibration case Shan Department
Should fill in the image to determine the speed
1G% sand fixed speed
High no-load stable transfer
Maximum sweep node speed
Low altitude fast Hook set speed
105% calibrated transfer
low cost load set speed
105% calibrated 1 condition with smoke
105% total reporting torque
105% calibrated 1. Condition: H torque
design: for non-oil-ban engines, serial number 4 is calibrated at 205% standard ratio, 105% calibrated 1 to take off the twist, etc.: for ship knife ten engines, net number 2:4, 6 is calibrated at 1U3%, E10% calibrated 1. Condition twist must be turned. Table 4: Test air transfer according to the holding rate
105% rated constant speed
with high altitude rescue speed
105% rated full speed
highest choice
1% rated speed
highest or stable speed
110% rated 15
110% rated 1 hot and humid
110% Calibration 1 said recent years
Let: For ship main engine, serial number 2.4, 6103% scaled speed, 110% scaled [said torch operation.
4.3.4.3 Power adjustment
JB/I511271999
When the test environment conditions are different from the standard environment test conditions, the power should be adjusted at 4:00 every day according to G/T1105.1, and run at the adjusted power.
4. 3. 4. 4 Maintenance
Before the reliability test, it is allowed to check or adjust the valve clearance, injection pressure and cylinder head screw tightening torque. During the reliability test, technical maintenance is carried out according to the cycle and content specified in Table 5. Maintenance time: single cabinet machine shall not exceed 2.5h, and the maximum time shall not exceed 10h. The additional time after machine maintenance shall not exceed 0min. Within the first "h" of continuous operation after maintenance, the "full" maintenance caused by slow disassembly and assembly is allowed. Table 5 shows the maintenance period and internal maintenance of oil engine. h
1 Clean the oil level on the engine and the control device
2 Clean the engine and the core, check the tires, and replace the belt
In addition to 1-3, training:bzxz.net
4 Replace the lubricant when necessary
5 Whether to upgrade the transmission belt
6 Check and adjust the spray inspection
Clean the carbon deposit on the nozzle, add some oil, clean the engine and wipe the engine blades when necessary. 1-8. Add
9 Clean the transformer and filter
Technical 4.3.4.5 Test record: Make a record of each test parameter every 4 hours, record the faults that occur during the test at any time, and make statistics according to the provisions of chapter 4.3.5 Starting test: Test item 4.3.1, 4.3.6 Performance retest: Test item 4.3.3.16 (under 4.2.3.). Before continuing, check or adjust the valve clearance, spray pressure, gas tightening torque and transmission belt tension, and remove carbon deposits from the spray nozzle (if necessary, it is allowed to clean the nozzle parts without adding abrasive paste) 4.2.7 Disassemble the machine and inspect the prototypes in pairs. Check the wear and damage of each key part. If found, the following parts should be carefully tested: piston, piston ring, piston pin, air filter, valve and pipe, valve seat, connecting rod bushing, connecting rod bearing, shaft, cam and camshaft, camshaft bushing, lifting column, rocker arm, etc. 4.4 Test report After the test is completed, the test report shall be filled in by the test unit according to the test results, including: 1) Appendix B (recommended appendix) reliability test sampling table; 2) Appendix (recommended appendix) engine test equipment, receiver list; 3) Appendix D (recommended appendix) engine performance test station result summary; 4) Appendix E (recommended appendix) reliability test failure record table. 5 Fault classification and judgment rules
5.1 Fault definition
5. 1. 1 Fault
Any diesel engine product that cannot complete its specified function under the specified test conditions and within the specified time is called a fault. 5.1.2 Fault
A fault caused by faults or defects in the diesel engine and its parts under the specified operating conditions, including performance degradation exceeding the specified limit.
5.1.3 Misuse fault
A fault caused by not using according to the specified conditions or due to external factors. For example, a fault caused by violating the operating procedures or not following the maintenance specified in the instruction manual.
5.1.4 Secondary fault
A secondary fault caused by a fault. For example, if the connecting rod of the diesel engine breaks and causes damage to the engine body or other parts, the damage to the engine body or other parts caused by this is considered a secondary fault. 5.2 Fault classification
According to the degree of harm caused by diesel engine failure, or the degree of severity of the damage and the difficulty of repair, the failure is divided into four categories: critical failure, general failure and minor failure. 5.2.1 Fatal failure (Class 1)
refers to failures that cause personal injury or death or major component damage or cause major economic losses, such as connecting rod or connecting rod breakage, flywheel cracking, and major component damage such as crankshaft and engine body. 5.2.2 Serious failure (Class II)
refers to failures in diesel engine performance exceeding the specified limit, major component damage, or failures that require disassembly to eliminate. The fuel consumption of the engine exceeds the specified limit, the air, piston, seal ring or bearing is damaged and needs to be replaced or there is serious leakage, etc.: [Major parts are extended according to F9771. 2 Disassembly refers to the disassembly of the air, gear room, oil corrosion, flywheel, 1. Lower engine body or manufacturing policy: 5.2.3 General discharge (old type)
refers to the shutdown for inspection and replacement of non-major parts and can be eliminated by random 1. Such as non-major parts damage, leakage, loose internal frozen parts, etc.
5. 2. 4 Minor faults (Class V)]
JES1127—1999
Includes faults that do not cause engine failure, do not require replacement of parts and can be corrected in a short time with random tools. Such as minor seepage, leakage, loose fasteners in non-important parts, etc.
5.3 Fault determination rules
5.3.1 When calculating the reliability index of diesel engines, only the number and category of essential faults are counted. If there are secondary faults caused by them, the number of faults will not be counted; but the fault category should be determined according to the most serious consequence caused by them. Misuse faults and other secondary faults caused by them are not counted. Make statistics. But they should be recorded in detail truthfully. 5.3.2 Any easy-to-grip parts that need to be replaced regularly according to the product manual should not be handled as faults. But records should be made. And it should be stated in the test report that the two structures are rigid and the machine must be stopped immediately to check the oil level and add oil at a certain rate. No fault shutdown treatment is required. 5.3.3 The fault category can be determined according to Appendix F (Appendix to the standard). Due to the different structures of the media lag, if a fault type not listed in Appendix F is found, its type can be determined according to the fault classification principle and with reference to the examples in Appendix F. 5.3,,4 The performance indicators of the prototype before the feasibility test shall comply with JB/T 5.3.5 During the trial operation, if the diesel engine temperature, pressure and other service parameters (such as exhaust gas overflow, cooling water temperature, oil temperature and oil pressure) do not meet the requirements of the product manual, timely inspection and treatment shall be carried out. If it is necessary to temporarily shut down or replace parts, the fault category shall be determined according to 5.3.1. 5.3.6 Under the specified use and maintenance conditions, if the diesel engine loses the specified kinetic energy or has damage, failure rate and belt loss due to internal reasons, this event shall be counted as a fault. 5.3.? Due to the failure of repair and maintenance 5.3. When the diesel engine is repaired for dust leakage, explosion, looseness, etc., one closed joint is counted as one time. 5.3.9 The calculation of the time of fault occurrence shall be based on the cumulative working time of the diesel engine when the fault occurs. If the fault occurs at the beginning of the test (during the test or performance test, when the cumulative working time is zero): If the fault is found during the prescribed maintenance, or during the performance review and engine inspection after the test, the cumulative working time of the diesel engine when the fault is found shall be calculated.3 The fault category can be determined according to Appendix F (Appendix of the standard). Due to the structural differences of the diesel engine, if a fault not listed in Appendix F is found, its category can be determined according to the fault classification principle and the examples in Appendix F. 5.3.4 The performance indicators of the prototype before the feasibility test shall meet the requirements of the corresponding product quality level of JB/T51104 (qualified products, first-class products or superior products). 5.3.5 During the feasibility test, if the diesel engine temperature, pressure and other service loads (such as exhaust gas overflow, cooling water temperature, oil temperature and oil pressure) do not meet the requirements of the product manual, timely inspection and treatment shall be carried out. If it is necessary to temporarily shut down or replace parts, the fault category shall be determined according to 5.3.1. 5.3.6 Under the specified conditions of use and maintenance, if the diesel engine loses the specified kinetic energy or suffers damage, failure rate and loss of power due to internal reasons, this event shall be counted as a fault. 5.3. If the fault is caused by poor maintenance or fault correction, the damage of the component shall not be counted as a fault. 5.3. When the diesel engine is repaired for dust leakage, explosion, loose nut, etc., one closed joint is counted as one time when the fault is not counted. 5.3.9 The calculation of the fault occurrence time shall be based on the cumulative working time of the diesel engine when the fault occurs. If the fault occurs at the beginning of the test (during the test or performance test, when the cumulative working time is zero): If the fault is found during the prescribed maintenance, or during the performance review and engine inspection after the test, the cumulative working time of the diesel engine when the fault is found shall be counted.3 The fault category can be determined according to Appendix F (Appendix of the standard). Due to the structural differences of the diesel engine, if a fault not listed in Appendix F is found, its category can be determined according to the fault classification principle and the examples in Appendix F. 5.3.4 The performance indicators of the prototype before the feasibility test shall meet the requirements of the corresponding product quality level of JB/T51104 (qualified products, first-class products or superior products). 5.3.5 During the feasibility test, if the diesel engine temperature, pressure and other service loads (such as exhaust gas overflow, cooling water temperature, oil temperature and oil pressure) do not meet the requirements of the product manual, timely inspection and treatment shall be carried out. If it is necessary to temporarily shut down or replace parts, the fault category shall be determined according to 5.3.1. 5.3.6 Under the specified conditions of use and maintenance, if the diesel engine loses the specified kinetic energy or suffers damage, failure rate and loss of power due to internal reasons, this event shall be counted as a fault. 5.3. If the fault is caused by poor maintenance or fault correction, the damage of the component shall not be counted as a fault. 5.3. When the diesel engine is repaired for dust leakage, explosion, loose nut, etc., one closed joint is counted as one time when the fault is not counted. 5.3.9 The calculation of the fault occurrence time shall be based on the cumulative working time of the diesel engine when the fault occurs. If the fault occurs at the beginning of the test (during the test or performance test, when the cumulative working time is zero): If the fault is found during the prescribed maintenance, or during the performance review and engine inspection after the test, the cumulative working time of the diesel engine when the fault is found shall be counted.
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