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GB/T 3821-2015Small and medium power internal combustion engines - Cleanliness limits and measurement methods (English PDF)

中小功率内燃机清洁度限值和测定方法

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Issued by

AQSIQ; SAC

Level / Type

National · Recommended

Issue date

December 10, 2015

Implementation date

July 1, 2016

Scope

GB/T 3821-2015 is the English-translated version of 中小功率内燃机清洁度限值和测定方法.

China's national standard for the cleanliness limits of small and medium power internal combustion engines and how they are measured. Cleanliness here means the mass of foreign particles left inside the engine when it leaves the factory - swarf from machining, casting sand, grinding dust, fibres from wipes, and the debris of assembly. It matters because an engine's bearings and its fuel injection equipment run on oil films measured in microns, and a particle larger than that film is dragged through the clearance and scores the surface. The damage is done in the first minutes of running, and it shortens the engine's life by an amount nobody can attribute afterwards, because the engine simply wears out early. Since the contamination cannot be removed once the engine is assembled, the limit has to be enforced during manufacture, which is why it is specified as a product requirement with a defined method of measurement rather than left to housekeeping.

Document preview — GB/T 3821-2015

National Standard of the People's Republic of China

ICS: 27.020
Classification: J 91

Issued by: General Administration of Quality Supervision, Inspection and Quarantine; Standardization Administration of the PRC

1 Scope
1.0 Cast aluminum 0.9
1.1 Calibration speed neb/(r/min) K2 >2000~3000 1.0 >3000
1.2 Total displacement Vb/L K1 >100~150 1.3 >150
1.4 Table
2 Normative references
3 Belt drive
3.0 Table
3.1 Machine cleanliness
3.2 Assembly cleanliness
3.2.5 Oil filter assembly
4 Cleanliness inspection work program diagram
4.00 Motorcycle, boat machine
5 Carburetor use G/mg General small gasoline engine with
5.1 Measuring instruments and cleaning fluids
5.1.1 Filter elements
5.1.1.1 Filter The micropore filter has a difference of not more than
5.1.2 Cleaning fluid
5.1.3 Appliances and devices
5.2 Working environment
6 Measurement items and parts
6.2 Parts and components (assembly)
7 Air compressor assembly crankcase inner surface and oil passage
7.1 Inspection preparation
7.2 Operation steps
7.2.1 Parts and components (assembly)
7.2.2 Machine
8 Filter material K Cast iron
9 Gears all surfaces
10 Shell and tube type 43 76
11 Crankcase material K
12 Crankshaft end drive mode K
13 Type a/mg b/(mg/m2) Plate fin type 7
16 Serial number part
17 Serial number part
Appendix A
Appendix B

Foreword

This standard was drafted in accordance with the rules given in GB/T 1.1-2009. This standard replaces GB/T 3821-2005 "Measurement method for cleanliness of medium and small power internal combustion engines", compared with GB/T 3821-2005 The technical changes are as follows:

--- Increased demagnetization requirements for parts prior to cleanliness inspection (see 7.1.7);

--- Increased cleanliness quality and particle limit requirements (see Chapters 3, 4). This standard was proposed by the China Machinery Industry Federation. This standard is under the jurisdiction of the National Internal Combustion Engine Standardization Technical Committee (SAC/TC177). This standard was drafted. Weichai Power Co., Ltd., Shanghai Internal Combustion Engine Research Institute, Guangxi Yuchai Machinery Co., Ltd., Changchai Co., Ltd., Kunming Yunnei Power Co., Ltd., Weichai Kaidong Power Machinery Co., Ltd., Ningbo Xuelong Group Fan Co., Ltd. The main drafters of this standard. Wang Jianping, Ji Weibin, Luo Zhijian, Dai Weilin, Yan Dehui, Yang Chunliang, Tao Shouping, Chen Nianhong, Guo Hua, Li Jianghu, Chen Lanlan, Yang Junjie, Meng Hongxia. The previous versions of the standards replaced by this standard are.

---GB/T 3821-1983, GB/T 3821-2005. Small and medium power internal combustion engine cleanliness limit and determination method

0.6

Note. For the oil pump installed inside the internal combustion engine, the limit of the external surface cleanliness of the assembly is determined by the OEM and the accessory factory.

3.2.3 Turbocharger The cleanliness limits for turbochargers are specified in JB/T 6002.

3.2.4 oil pump nozzle The cleanliness limit of the diesel oil pump nozzle is specified in JB/T 7661.

1 Scope

This standard specifies the limits of cleanliness of small and medium-sized internal combustion engines (hereinafter referred to as internal combustion engines), measurement items and locations, measurement conditions, and determination. method. This standard applies to the whole machine and parts of internal combustion engines.

1.0 Cast aluminum 0.9

3.2.5.2 Centrifugal oil filter assembly cleanliness, expressed in WR2 (mg) per mass, see Table 9 for limits. Table

9 Rotor inner diameter d/mm WR2/mg Cast iron filter seat cast aluminum filter seat <=100 120 108 >100 150 135

3.2.6 Air compressor assembly The cleanliness of the air compressor assembly is expressed in WK (mg) per mass, and the limit is calculated according to formula (6). WK=a(K1K2K3

b) (6) In the formula. a

--- empirical constant, 50mg; K1

--- total displacement correction coefficient, the value is shown in Table 10; K2

---Material correction coefficient, the values are shown in Table 11; K3

---Crankshaft end transmission mode correction factor, the value is shown in Table 12; b

--- The number of drive pairs on the drive shaft. Table

1.1 Calibration speed neb/(r/min) K2 >2000~3000 1.0 >3000

0.9 table

3 Calibration power Peb/kW G/mg <=3.68 50 (two strokes) 80 (four strokes) >3.68~7.35 150 >7.35~

14.7.200 Calibration power Peb/kW G/mg >14.7~29.4 400~aPeb >29.4~73.5 0 >73.5 500~0.5aPeb

3.1.2 The cleanliness of the whole engine of the internal combustion engine is calculated according to formula (2). W =4.66iSD (2) In the formula. W

--- Cleanliness limits for internal combustion engines in milligrams (mg); i

--- number of cylinders; S

--- piston travel of the internal combustion engine in centimeters (cm); D

--- Cylinder diameter of the internal combustion engine in centimeters (cm).

2 Normative references

The following documents are indispensable for the application of this document. For dated references, only dated versions apply to this article. Pieces. For undated references, the latest edition (including all amendments) applies to this document.

GB 1922-2006 Solvent oil for paints and cleaning

GB/T 5330 industrial wire braided square hole screen

GB/T 23338 internal combustion engine charge air cooler technical conditions

JB/T 6002 turbocharger cleanliness limit and method of determination

JB/T 7661 diesel engine oil pump nozzle product cleanliness limit and determination method

3 Belt drive

1.0 gear drive 1.1 (excluding gears) 1.2 (including gears)

3.2.7 oil cooler assembly The cleanliness of the oil cooler assembly is expressed in WL (mg) per impurity, and the limit is calculated according to equation (7). WL=a bF0 (7) In the formula. a

--- empirical constant, the unit is milligram (mg), the value is shown in Table 13; b

--- empirical constant, the unit is milligrams per square meter (mg/m2), the values are shown in Table 13; F0

---oil side heat transfer area in square meters (m2). Table

3.1 Machine cleanliness

3.1.1 The cleanliness of the internal combustion engine is expressed in terms of each impurity mass W, and the limit is calculated according to formula (1). W = aK1K2Peb G (1) In the formula. W

--- Cleanliness limits for internal combustion engines in milligrams (mg); a

--- empirical constant, 13.6mg/kW; K1

---total displacement correction coefficient, the value is shown in Table 1; K2

---speed correction coefficient, the value is shown in Table 2; Peb

---calibrated power in kilowatts (kW); G

--- compensation amount, the unit is milligram (mg), the value is shown in Table 3. Table

3.2 Assembly cleanliness

3.2.1 Carburetor assembly The cleanliness of the carburetor assembly is expressed in terms of each impurity mass WH (mg), and the limit is calculated according to formula (3). WH=a KV G (3) In the formula. a

--- empirical constant, 10mg; K

---volume correction factor, the unit is milligrams per cubic centimeter (mg/cm3), the values are shown in Table 4; V

--- carburetor volume, in cubic centimeters (cm3), measured by volumetric method; G

--- compensation amount, the unit is milligram (mg), the value is shown in Table 5. Table

3.2.5 Oil filter assembly

3.2.5.1 Wire-wound, blade-type, paper, linoleum filter oil filter assembly cleanliness is expressed in WR1 (mg) per mass, limit Equation (5) calculation. WR1=aKQ (5) In the formula. a

--- empirical constant, the unit is milligrams per liter (mg · min/L), the values are shown in Table 7; K

---material correction coefficient, the value is shown in Table 8; Q

---rated flow in liters per minute (L/min). Table

4 Cleanliness inspection work program diagram

7.2.1.2 Sampling. According to the sampling method specified by the enterprise.

7.2.1.3 Disintegration. Disassemble the assembly that requires disintegration as specified in Chapter 6. Avoid scratching and bumping parts during the disintegration process. Collecting and processing foreign matter obtained in the process of disintegration that is not within the cleanliness assessment range (damaged paper pad and metal scraps scraped off by spring washers, etc.). After the parts to be inspected are numbered, they are placed on special equipment for cleaning.

7.2.1.4 Cleaning. According to the shape and size of the parts and assemblies, use a syringe, nylon brush and solvent oil (usually 50kPa). Flush the surface to be tested. For deep holes, conduits, and inner surfaces of castings, use 100 mL to 150 kPa of pressurized solvent oil.

7.2.1.5 Clean all the metal impurities in the non-through holes, remove them all (such as magnets to remove iron filings, etc.) and count the impurities.

7.2.1.6 When flushing with various appliances, the cleaning solution with impurities should be prevented from splashing out of the container and all cleaning liquid with impurities should be collected.

7.2.1.7 Parts or parts that are not suitable for cleaning with solvent oil during cleaning are cleaned with 90% ethanol, but it should be noted that the two cleaning solutions are not Use it at the same time and prevent accidents.

7.2.1.8 Filtration. The entire cleaning solution is coarsely filtered with a strainer to initially collect impurities; then vacuum filtration is performed using a filter membrane. Collect all impurities (package Including metal impurities such as iron filings, non-metallic particles falling from inspection tools such as brushes should be removed.

7.2.1.9 Drying. Wash the oil on the filter with the cleaning solution, put the filter together with the filtered impurities into the weighing bottle, and make the cap open halfway. It was taken out in an oven at 90 ° C ± 5 ° C for 60 min, and cooled in a desiccator for 30 min; the oil on the filter screen was washed with a cleaning solution. It was taken out in an oven at 150 ° C ± 5 ° C for 60 min and cooled in a desiccator for 30 min.

7.2.1.10 Weighing. Weigh and dry the wire filter and the weighing bottle with the impurity filter on the balance, the reading is accurate To 0.1mg.

7.2.1.11 Particle detection. The maximum particle size (length x width, µm x µm) in the impurities was examined by microscopy and filled in Table 18.

7.2.1.12 Analysis. analysis of impurity components (only metal impurities are required to be taken out); and 40 cm × 40 cm square glass or microscope carrier glass The granules crush the granules to determine their hardness. The mass of the impurities was calculated according to the formula (8), and the results were filled in Table 18. W =(G2-G1) (G4-G3) G5 (8) In the formula. W

--- impurity quality in milligrams (mg); G1

--- the mass of the filter before filtration, in milligrams (mg); G2

--- filter mass after filtration, in milligrams (mg); G3

5.1.1.1 Filter The micropore filter has a difference of not more than

0.4 mg twice. The specifications are as follows:

a) 4.5µm microporous membrane, when the cleanliness requirement of the parts is not more than 5mg, filter the sample for testing;

b) 5µm microporous membrane filter, when the component cleanliness requirement is greater than 5mg, filter the sample for testing.

5.1.1.2 Filter The filter size is 430 mesh, the material is stainless steel wire, and meets the requirements of GB/T 5330.

5.1.1.3 Vacuum pump and membrane filtration device Vacuum pump (vacuum degree 80kPa), filter membrane filter device consists of funnel, funnel seat, metal frame, rubber stopper, suction filter bottle, its connection form see picture 1. Description. 1

---filter membrane; 3

---Funnel seat; 4

---rubber plug; 5

--- suction filter bottle; 6

---metal frame; 7

---connecting pipe; 8

---Connected to the vacuum pump. Figure

5.1.2 Cleaning fluid

5.1.2.1 The cleaning solution should be cleaned before use. The cleanliness of 400mL cleaning solution is not more than 1mg.

5.1.2.2 No. 2 solvent oil (oxygen-free hydrocarbon cleaning agent) specified in GB 1922-2006. 5.1.2.3 90% industrial ethanol.

5.1.3 Appliances and devices

5.1.3.1 Disassembly equipment and tools Special equipment such as cranes and flip racks, as well as general disassembly equipment and tools.

5.1.3.2 Cleaning equipment and tools Cleaning equipment and tools include.

a) Nylon round brushes, flat brushes, etc. of various sizes, all brushes should be white and cleaned in the cleaning solution before use, cleaning The diameter of the round brush of the hole should be larger than the diameter of the hole to be cleaned;

b) cleaning bottles and syringes, etc.;

c) containers of different sizes of basins and buckets with lids;

e) a flat, toothless tweezers;

f) The whole machine and heavier parts and assemblies shall be equipped with special cleaning equipment that can be rotated;

g) Pressure washer (pressure is.200kPa~250kPa), as shown in Figure 2. Description. 1

--- air compressor; 2, 5

--- connecting pipe; 3

--- air filter; 4

--- pressure gauge; 6

--- spray gun; 7

---Liquid tank. Figure

5.2 Working environment

5.2.1 Cleanliness inspection should be set up with a special inspection room. The room is divided into operation rooms such as disintegration, cleaning, filtration, drying, weighing and analysis. The recommended layout is shown in Figure 3. Description. 1

---disintegration and large-size cleaning room; 2

---small cleaning room; 3

---filter room; 4

---drying, weighing, and analysis; 5

---sample display room. Figure

6 Measurement items and parts

6.1 Machine The measurement items and parts of the whole machine shall comply with the provisions of Table 15; the items and parts of the whole machine disassembly test are shown in Appendix C. Table

15 Serial number part 1 inner surface of oil sump (including magnetic screw surface)

2 Oil strainer assembly all parts surface (except the outer surface of the assembly) 3 oil fine filter assembly all parts surface (except the outer surface of the assembly) 4 oil oil (including oil pan, oil, fine filter and oil cooler, etc.)

6.2 Parts and components (assembly)

6.2.1 Parts The measurement location of the part shall comply with the requirements of Table 16. Table

7 Air compressor assembly crankcase inner surface and oil passage

8 oil radiator (cooler) contact with lubricating oil surface and oil passage

9 oil filter assembly assembly all surface

10 oil gauge assembly outer surface 11 supercharger inlet pipe assembly inner surface

Note. Pressure fittings and non-removable connectors are not disassembled.

7.00

Note. The compensation amount of various matching carburetor is based on low value.

3.2.2 oil pump assembly The cleanliness of the oil pump assembly is expressed in terms of each mass of WJ (mg). When the oil pump displacement q <= 0.005L, the limit is 20mg; When the oil pump displacement q >0.005L, the limit is calculated according to formula (4). WJ=a bKq (4) In the formula. a

--- empirical constant, 10mg; b

--- empirical constant, 2 × 103 mg/L; K

---Material correction coefficient, the value is shown in Table 6; q

--- Oil pump displacement in liters (L). See Appendix A for the calculation formula of the oil pump displacement. Table

7.1 Inspection preparation

7.1.1 Staff should wear clean overalls, caps and shoes and wash hands.

7.1.2 Clean the non-inspected parts of the parts.

7.1.3 Clean all sampling tools, brackets and containers.

7.1.4 Filter the cleaning solution with a 4.5µm or 5µm filter.

7.1.5 The filter screen is placed in the cleaning solution for 10 minutes and then taken out. After the cleaning solution is volatilized, it is placed in an oven at 105 °C ± 5 °C. After 60 min, it was taken out in a dry box and cooled for 30 min, and then weighed for use.

7.1.6 Put the filter into the weighing bottle with tweezers, put the half-open cover into the oven that has been heated at 90 °C ± 5 °C, take it out after 60 min, and place it in the dry After cooling for 30 minutes in the dry box, weigh it for use. (If necessary, use multiple filters to dry and weigh together, but each weighing bottle should not exceed 3 sheets, the filter membranes are required to be staggered from each other), and the difference between the weighing of the filter and the drying of the filter is not more than

0.4 mg.

7.1.7 The parts to be inspected shall be demagnetized before cleaning. The residual magnetism of the fuel system parts shall not exceed 5×10-4T, and the remanence of other parts The amount is not more than 1.5×10-3T.

7.2.1 Parts and components (assembly)

7.2.1.1 The measurement of the cleanliness of parts and components (assembly) includes sampling, disassembly, cleaning, filtration, drying, analysis, etc. The sequence is shown in Figure 4. Figure

7.2.2 Machine

7.2.2.1 For the whole machine that has been coated with anti-rust oil, whether the anti-rust oil should be cleaned or replaced before testing, can be according to the product manual. Line processing. When adding oil according to the product manual, the mechanical impurities should meet the requirements of the corresponding standards, and run for 30 minutes. The above measurement can be carried out only when the oil temperature reaches 65 °C (the two-stroke small gasoline engine can be measured after 30 minutes of hot operation).

7.2.2.2 Collect all oil in the oil pan, oil coarse, fine filter and oil radiator (cooler).

7.2.2.3 Disassemble the oil coarse and fine filter cover, remove the filter after disassembly (except for disassembly), immerse it in a container containing the cleaning solution, and Flush the inner surface of the housing.

7.2.2.4 Clean the inner surface of the oil pan including the magnetic plug surface.

7.2.2.5 Collect all cleaning fluids with impurities.

7.2.2.6 Filter, dry, weigh, pellet and analyze according to 7.2.1.8~7.2.1.12.

10 Shell and tube type 43 76

3.2.8 Charge air cooler assembly The charge air cooler is specified in GB/T 23338.

3.3 Main parts cleanliness limits The cleanliness limits for major parts are specified in Table 14. The cleanliness limits for other parts of the internal combustion engine that do not have specified limits are subject to the supply agreement. The standard is executed. Table

14 Serial number name (piece) limit/mg 1 cylinder head 0.48iD 2 body 1.62D 3 crankshaft 0.14iD 4 camshaft 3.5i 5 rocker shaft 6i 6 rocker seat 12 7 rocker 7 8 oil filter seat 22 9 gear

12 Table 14 (continued) Serial number name (piece) limit/mg 10 gear chamber cover 12 11 cylinder liner 10 12 valve tappet 12 13 valve stem 17 14 high pressure oil pipe 2.5l 15 cylinder head cover 14i 16 piston 14 17 piston ring 5 18 link 35 19 main bearing bush and connecting rod bearing bush 4 20 diesel filter 6 21 fuel filter 6 22 oil sump 0.06iD 23 intake pipe (including manifold) 0.06iD 24 exhaust pipe 0.12iD

Note. D is the cylinder bore of the internal combustion engine, the unit is millimeter (mm); i is the number of cylinders of the internal combustion engine; l is the length of the high pressure fuel pipe, the unit is meter (m).

16 Serial number part

1 All internal surfaces of the cylinder head (except water passages and screw holes), including air passages, oil passages and combustion chambers

2 All internal surfaces of the body (except waterways and screw holes), including air passages and oil passages

17 Serial number part

1 Fuel gross filter and fine filter assembly all parts surface (except for the outer surface of the assembly) 2 carburetor assembly all parts surface (except the outer surface of the assembly)

3 All parts of the fuel injection pump assembly (except for the outer surface of the assembly) 4 oil pump assembly all parts surface (except the outer surface of the assembly)

5 Injector assembly all parts surface (except for the outer surface of the assembly)

6 Oil strainer and fine filter assembly all parts surface (except the outer surface of the assembly)

Appendix A

(normative appendix) Oil pump displacement calculation formula The oil pump displacement q(L) is approximated by the formula (A.1) or the formula (A.2) (calculated to the nearest 0.0001). External meshing involute gear pump. q=pi4 (D2e-D2i) B×10-6 (A.1) Internal meshing involute gear pump. q=pi4 (rho 1-rho 2) B×10-6 (A.2) In the formula. De

---the diameter of the tip circle, in millimeters (mm); Di

--- tooth root diameter, in millimeters (mm); B

--- tooth width in millimeters (mm); Rho1

--- inner rotor long diameter in millimeters (mm); Rho2

--- The inner rotor has a short diameter in millimeters (mm).

Appendix B

(normative appendix) Indoor dustfall determination method B.1 General The method is applicable to the determination of dustfall in various operation rooms, working chambers, and impurity sample storage rooms. The amount of dust in the room refers to the amount of dust that falls on the unit area of the designated part within a certain period of time (usually measured for 24 hours of dust reduction). Expressed in mg/m2. B.2 Equipment and equipment B.2.1 White porcelain plate (300mm × 250mm) or glass plate. B.2.2 Filter membrane filter. See 5.1.1.1. B.3 Determination method B.3.1 Sampling B.3.1.1 Put the tested environment in a normal working state. B.3.1.2 Place the white porcelain plate (one or more) coated with organic...

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This preview omits tables, figures, formulas and parts of the technical clauses. The complete document — 29 pages — is available in the English PDF.

Referenced standards

Normative references

GB 1922-2006 · JB/T 6002 · JB/T 7661

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