JB/T 8889-1999 This standard specifies the definition, type and basic parameters, technical requirements, test methods, inspection rules, marking, packaging, transportation and storage of grain coolers. This standard applies to grain coolers equipped with compressors with a power greater than 2kW. JB/T 8889-1999 Grain Cooler JB/T8889-1999 Standard download decompression password: www.bzxz.net

JB/T8889-1999
Appendix A of this standard is the appendix of the standard. Fore
This standard is proposed and managed by the National Technical Committee for Standardization of Refrigeration Equipment. The responsible drafting units of this standard are: Hefei General Machinery Research Institute, China International Engineering Consulting Corporation, Beijing Dongfang Fude Technology Development Center, Yantai Binglun Group, Dalian Bingshan Group. The main drafters of this standard are: Fan Gaoding, Shi Min, Dai Shilong, Wang Zhe, Hao Wei, Chen Jinhua, Yu Ming. 1274
1 Scope
Machinery Industry Standard of the People's Republic of China
Grain chillers
Grain chillers
JB/T 8889-1999
This standard specifies the definition, type and basic parameters, technical requirements, test methods, inspection rules, marking, packaging, transportation and storage of grain chillers.
This standard is applicable to grain chillers with compressor power greater than 2kW. 2 Referenced standards
The provisions contained in the following standards constitute the provisions of this standard through reference in this standard. When this standard is published, the versions shown are valid. All standards will be revised, and the parties using this standard should explore the possibility of using the latest versions of the following standards. GB191-1999 Pictorial signs for packaging, storage and transportation
GB/T2423.17—1993 Basic environmental testing procedures for electric and electronic products Test ka: Salt spray test method
GB/T6388—1986 Shipping and receiving marks for transport packaging GB/T 13306—1991 Labels
JB/T4330--1999 Determination of noise for refrigeration and air-conditioning equipment JB/T7249—1994 Terminology for refrigeration equipment
JB8655—1997
Safety requirements for unitary air conditioners
3 Definitions
This standard adopts the following definitions. Other definitions shall comply with the provisions of JB/T7249. 3.1 Grain cooler
A device used for low-temperature storage of grains, providing air with a certain temperature and humidity to the granary. It mainly includes a refrigeration system, air supply and purification devices, and may also include humidity control and air volume adjustment devices. 3.2 Air supply volume
The amount of air delivered to the granary per unit time, in m/h. The air supply volume of the grain cooler during operation in any state shall be converted into the value under the state of 20, 101kPa and relative humidity of 65%. 3.3 Refrigeration capacity
The heat removed from the air entering the grain cooler by the grain cooler under the specified refrigeration capacity test conditions, in kW. 3.4 Power consumption
The total power consumed by the grain cooler during operation, in kW. 3.5 Air supply per unit power
The ratio of air volume to power consumption. Its value is expressed in m\/h·kW. 3.6 Refrigeration coefficient of performance (cop)
The ratio of cooling capacity to power consumption, expressed in kw/kW. Approved by the State Bureau of Machinery Industry on August 9, 1999 and implemented on August 15, 1999
3.7 Air flame difference method
JB/T8889
A method for determining the capacity of a grain cooler. It measures the inlet parameters, outlet parameters and circulating air volume of the grain cooler, and determines the cooling capacity of the grain cooler by multiplying the measured air volume by the inlet and outlet flame difference. 4 Types and basic parameters
4.1 Types
4.1.1 Grain coolers are divided into the following according to climate:
a) Type A represents tropical type, with the code GLA; b) Type B represents temperate type, with the code GLB. 4.1.2 Model compilation of grain cooler
The model of grain cooler consists of uppercase Chinese phonetic letters and Arabic numerals, and the specific expression method is: 0
Code of grain cooler
Model example: Grain cooler with nominal cooling capacity of 42kW and type A, GLA42. 4.2 Basic parameters
4.2.1 The basic parameters of type A content cooler shall be in accordance with the provisions of Table 1. Table 1 Basic parameters of type A grain cooler
Nominal cooling capacity
>5～14
>14～28
>28～50
>50～80
>80～100
>100～150
4.2.2 The basic parameters of type B grain cooler shall be in accordance with the provisions of Table 2. Refrigeration performance coefficient
4.2.3 The unit power air supply of the grain cooler is determined according to the nominal working condition parameters of 6.1.2. 1) Factory design serial number and special function code, etc. Chinese pinyin capital letters are allowed. 2) Nominal T-condition cooling capacity, number × 10°W. 3) Type: Type A, Type B.
Air volume per unit power
m*/(h-kw)
5 Technical requirements
5.1 General requirements
JB/T8889—1999
Table 2 Basic parameters of type B grain cooler
Nominal cooling capacity
>5～14
≥>14～28
>28～50
>50～80
>80～100
>100～150
Coefficient of performance
Air volume per unit power
m/(h-kw)
Grain coolers shall comply with the requirements of this standard and be manufactured according to the drawings and technical documents approved through the prescribed procedures. 5.1.1
5.1.2 The surface of the ferrous metal parts of the grain cooler should be treated with anti-corrosion. 5.1.3 The surface of the electroplated parts should be smooth and uniform in color, without peeling, pinholes, obvious spots and scratches. 5.1.4 The surface of the painted parts should not have obvious bubbles, flow marks, missing paint, primer exposure, wrinkles and other damage. 5.1.5 The surface of decorative plastic parts should be flat and uniform in color, without defects such as cracks, bubbles and obvious shrinkage holes, and plastic parts should be resistant to aging. 5.1.6 The installation of various parts of the grain cooler should be firm and reliable, and there should be no friction and collision between the pipeline and parts. 5.1.7
The various valves of the grain cooler should be sensitive and reliable to ensure the normal operation of the grain cooler. The insulation layer of the grain cooler should have good thermal insulation performance, be non-toxic and odorless, and have self-extinguishing properties. 5.1.8
The materials of the refrigeration system parts of the grain cooler shall not deteriorate under the action of refrigerants, lubricating oils and their mixtures and ensure the normal operation of the whole machine.
5.1.10 The safety requirements of the grain cooler, such as voltage resistance test, insulation resistance, waterproofing, etc., shall comply with the provisions of JB8655. 5.1.11 The grain cooler shall be able to operate normally under the following conditions: a) Ambient temperature -10~43C;
b) Ambient humidity 50%~95%.
5.1.12 The air outlet parameter range and control accuracy of the grain cooler are as follows: When the outlet temperature of the grain cooler is set at 7~18C, the control accuracy is: average ±0.3℃, maximum ±1C; when the relative humidity is set at 65%~90%, the control accuracy is: average ±3%, maximum ±6%. 5.1.13 Electroplated parts shall meet the following requirements: After testing according to method 6.3.11, the area of ​​each rust spot on the metal coating shall not exceed 1mm2; there shall be no more than two rust spots or rust spots on the coating of each 100cm2 test piece, and there shall be no rust spots or rust spots if the coating is less than 100cm2. 5.1.14 Paint film adhesion requirements for painted parts: After testing according to method 6.3.12, the number of paint film falling grids shall not exceed 15%. 5.2 Grain cooler parts
All parts of grain coolers shall meet the relevant standards. 5.3 Performance requirements
5.3.1 Refrigeration system sealing performance
When testing according to method 6.3.1, there shall be no refrigerant leakage in all parts of the refrigeration system. 5.3.2 Operation
JB/T 8889-1999
When testing according to method 6.3.2, the measured current, voltage, input power and other parameters shall meet the design requirements. 5.3.3 Refrigeration capacity
When tested according to the method in 6.3.3, the measured nominal refrigeration capacity of the grain cooler should not be less than 95% of the nominal refrigeration capacity. 5.3.4 Power consumption
When tested according to the method in 6.3.4, the measured nominal power consumption of the grain cooler should not be greater than 110% of the nominal power consumption. 5.3.5 Air volume
When tested according to the method in 6.3.5, the measured nominal air volume should not be less than 95% of the nominal air volume. 5.3.6 Maximum power operation
a) According to 6.3.During the test of method 6, the parts of the grain cooler should not be damaged and the grain cooler should be able to operate normally; b) During the operation of the grain cooler at maximum power, the overload protector should not trip; c) When the grain cooler is shut down for 5 minutes and then restarted to run continuously for 1 hour, the overload protector is allowed to trip within the first 5 minutes of the startup operation, and is not allowed to operate thereafter; if the overload protector is not reset within the first 5 minutes of operation, it should be reset within no more than 30 minutes of shutdown and should be able to run continuously for 1 hour;
d) For the manually reset overload protector, if it trips within the first 5 minutes, it should be forced to reset 10 minutes after the trip, and should be able to run continuously for another 1 hour.
5.3.7 Condensate removal capacity
When testing according to method 6.3.7, no condensate should overflow or blow out from places other than the drain outlet. 5.3.8 Noise
Noise measurement should be carried out on grain coolers. When the noise measurement value of grain coolers exceeds the noise limit of relevant regulations, the unit should be soundproofed and the noise sound pressure level should be evaluated according to the measured value after treatment. 5.3.9 Partial load regulation performance
The regulating device of grain coolers with energy regulation should be sensitive and reliable. 5.3.10 Refrigeration coefficient of performance (cop)
The ratio of the cooling capacity measured by method 6.3.3 to the power measured by method 6.3.4 should not be less than 95% of the value specified in 4.2. 5.3.11 Unit power air volume
The ratio of the air volume measured by method 6.3.5 to the power consumption measured by method 6.3.4 should not be less than 95% of the value specified in 4.2. 5.3.12 When moving grain coolers, they should be safe, reliable, flexible, convenient and not easy to tip over. 5.3.13 When the static pressure of the grain cooler air outlet changes from 980Pa to 2940Pa, the change in air volume should not exceed 25%. 5.3.14 The trouble-free working time of the grain cooler should be not less than 8000h. 6 Test method
6.1 Test conditions
6.1.1 See Appendix A (Standard Appendix) for the test device of the air supply volume and refrigeration capacity of the grain cooler. 6.1.2 Test conditions
6.1.2.1 Nominal test conditions for Type A units are shown in Table 3. Table 3 Nominal test conditions for Type A units
Air inlet status
Dry bulb temperature
Relative humidity
6.1.2.2 Nominal test conditions for Type B units are shown in Table 4. 1278
Dry bulb temperature
Air outlet status
Relative humidity
Outlet static pressure
Dry bulb temperature
Air inlet status
Relative humidity
JB/T8889-1999
Table 4 Nominal test conditions for Type B units
Air outlet status
Dry bulb temperature
6.1.2.3 Other test conditions are shown in Table 5 for Type A and Table 6 for Type B. Table 5 Other test conditions for type A units
Air inlet status
Dry bulb temperature
1) Condensate condition.
2) Maximum power condition,
Air inlet status
Dry bulb temperature
1) Condensate condition.
2) Maximum power condition.
6.1.3 Measuring instruments
6.1.3.1 General provisions
Relative humidity
Relative humidity
Air outlet status
Dry bulb temperature
Table 6 Other test conditions for type B units
Air outlet status
Dry bulb temperature
The test instruments shall be qualified after verification and within the validity period. 6.1.3.2 Type and accuracy of test instruments and meters The type and accuracy of test instruments and meters shall comply with the provisions of Table 7. Table? Type and accuracy of instruments and meters
Temperature measuring instruments
Relative humidity measuring instruments
Refrigerant pressure measuring instruments
Mercury in glass thermometer
Resistance thermometer
Thermocouple
Humidity sensor
Pressure gauge, transmitter
Relative humidity
Relative humidity
Relative humidity
Outlet static pressure
Outlet static pressure
980,29402
980,2940
9801\,1 960,2 940
Outlet static pressure
980\, 2940
980.29402)
1960.2940
Air temperature ±0.1℃
Air pressure measuring instrumentbzxz.net
Electricity measuring instrument
Mass measuring instrument
JB/T8889-
—1999
Table 7 (end)
Barometer, air pressure transmitter
Indicating type
Integrating type
1 The accuracy of the air pressure measuring instrument used for atmospheric pressure measurement is ±0.1%. 2 The accuracy of the time measuring instrument is ±0.2%. 3 The measurement value of the measuring instrument defined by accuracy should be above 1/2 of the instrument range. 6.1.4 The temperature fluctuation tolerance of the grain cooler shall comply with the provisions of Table 8. Table 8 Fluctuation tolerance of test parameters of grain cooler items
Maximum fluctuation range
Average fluctuation range
6.2 General requirements for testing
Air inlet state
Dry bulb temperature
Relative humidity
Duct static pressure ±2.45Pa
Air outlet state
Dry bulb temperature
Relative humidity
6.2.1 All tests of grain coolers shall be carried out according to the rated voltage and rated frequency on the nameplate. 6.2.2 All auxiliary components (including air inlet louvers and pipes and accessories manufactured by the installation factory) shall be connected during the test and the air circuit shall remain unchanged.
6.3 Test method
6.3.1 Refrigeration system sealing performance test
The refrigeration system of the grain cooler shall be tested with a refrigerant leak detector with a sensitivity of 1×10-'Pa·m\/s under normal refrigerant filling amount.
6.3.2 Operation test
The grain cooler shall be operated continuously under conditions close to the nominal refrigeration conditions, and the input power, operating current and inlet and outlet air temperatures of the grain cooler shall be measured respectively. Check the sensitivity and reliability of the safety protection device, and check whether the operation of the temperature, electrical appliances and other control components is normal. 6.3.3 Refrigeration capacity test
The test shall be carried out according to the nominal operating conditions specified in Appendix A and 6.1.2. 6.3.4 Power consumption test
Measure the input power and current of the grain cooler at the same time as the refrigeration capacity is measured according to the method given in Appendix A. 6.3.5 Air volume test
Carry out the air volume test according to the method given in Appendix A and the manufacturer's instructions and the nominal operating conditions specified in 6.1.2. 6.3.6 Maximum power test
At rated frequency and rated voltage, run continuously for 1 hour after stabilization according to the maximum power operating conditions specified in 6.1.2, then stop for 5 minutes (the voltage rise during this period shall not exceed 3%), and then restart and run for 1 hour. 6.3.7 Condensate removal capacity test
Run for 1 hour under the operating conditions specified in 6.1.2.
6.3.8 Noise test
The noise test is carried out according to the method of measuring the surface of a rectangular hexahedron in JB/T4330, and the measurement positions are measured according to points 1, 2, 3, and 4 in Figure B2 and Table B2 of Appendix B (Appendix of the standard). The sound pressure level is calculated according to the surface average sound pressure level method of JB/T4330. 6.3.9 Salt spray test for electroplated parts
JB/T 8889—1999
The electroplated parts of grain coolers shall be subjected to salt spray test in accordance with GB/T2423.17. The test period is 24 hours. Before the test, the surface of the electroplated parts shall be cleaned and degreased. After the test, the salt remaining on the surface shall be washed off with clean water. The corrosion of the electroplated parts shall be checked. The results shall comply with the provisions of 5.1.10. 6.3.10 Adhesion test of paint film on painted parts Take an area of ​​10 mm in length and 10 mm in width on the outer surface of the body and use a new razor blade to make 11 parallel cuts with a spacing of 1 mm and a depth of 1 mm to the substrate. Stick it firmly with zinc oxide medical tape, and then tear it off quickly in the vertical direction. The ratio of the number of grids where the paint film falls off to 100 within the scratch range shall be evaluated. If the paint film retains less than 70% of each grid, it shall be considered as falling off. After the test, check the paint film peeling condition, and the result should comply with the provisions of 5.1.14.
6.3.11 Water spray test
The water spray test shall be carried out in accordance with the relevant test methods in JB8655. 6.3.12 Grain cooler aerodynamic characteristic curve test quantity.
Measure the air supply of the grain cooler under different outlet static pressure conditions: 650Pa, 980Pa, 1470Pa, 1960Pa, 2940Pa. 7 Inspection rules
7.1 Factory inspection
Each grain cooler shall be inspected at the factory, and the inspection items shall be in accordance with the provisions of Table 9. 7.2 Sampling inspection
Grain coolers shall be sampled from the products that have passed the factory inspection for sampling inspection. The inspection items shall be in accordance with the provisions of Table 9. 7.3 Type inspection
Type test shall be carried out in the following cases, and the inspection items shall be in accordance with the provisions of Table 9: a) New products;
b) Major improvements to the finalized products.
Table 9 Inspection Items
General Inspection
Insulation Resistance
Withstand Voltage Test
Leakage Current
Grounding Resistance
Protection Against Electric Shock
Sealing of Refrigeration System
Refrigerating Capacity
Power Consumption
Maximum Power Test
Condensate Removal Capacity Test
Refrigeration Performance Coefficient||tt ||Air supply per unit power
Water spray test
Aerodynamic characteristic curve
Salt spray test for electroplated parts
Paint film adhesion for painted parts
Factory inspection
Sampling inspectionType inspection
Technical requirements
JB8655
JB8655
Test method
JB8655
6. 3.3;6. 3. 4
6.3.5;6.3.4
8 Marking, packaging, transportation and storage
8.1 Marking
JB/T 8889-1999
8.1.1 Each grain cooler shall have a durable nameplate fixed in a conspicuous position. The size and technical requirements of the nameplate shall comply with the provisions of GB/T13306. The following contents shall be marked on the nameplate: a) Name of the manufacturer;
b) Product model and name;
c) Main technical performance parameters (cooling capacity, air supply, refrigerant code and its charge, voltage, frequency, number of phases, total installed power, weight and overall dimensions);
Note: If the grain cooler is equipped with an auxiliary electric heater, add a bracket after the value of "total installed power" and indicate the power value of the electric heater in the bracket.
d) Product factory number;
e) Year and month of manufacture.
8.1.2 The grain cooler shall have a sign indicating the operating status, such as a clear grounding mark, an arrow indicating the direction of rotation of the fan, and markings indicating instruments and control buttons.
8.1.3 Factory documents
Each grain cooler shall be accompanied by the following technical documents:8.1.3.1 Product certificate. Its contents include:a) Product name and model;
b) Product factory number;
c) Inspector's signature and seal;
d) Inspection date.
8.1.3.2 Product instruction manual, its contents include:a) Product model and name, applicable scope, implementation standard, grain cooler's aerodynamic characteristic curve, technical parameters under nominal working conditions, noise and other main technical parameters, etc.;b) Product structural diagram, refrigeration system diagram, circuit diagram and wiring diagram;c) Spare parts catalog and necessary vulnerable parts diagram;d) Installation instructions and requirements;
e) Instructions for use, repair and maintenance precautions.8.1.3.3 Packing list
8.2 Packaging
8.2.1 The grain cooler should be cleaned before packaging. All parts should be clean and dry, and rust-prone parts should be coated with rust-proof agent. 8.2.2 The grain cooler should be covered with plastic bags or moisture-proof paper and fixed in the box to prevent moisture and mechanical damage during transportation. 8.2.3 The following marks should be on the packaging box of the grain cooler: a) Name of the manufacturer;
b) Product model and name;
c) Net weight, gross weight:
d) Overall dimensions:
e) "Handle with care", "Upward", "Afraid of moisture" and "Afraid of pressure". Regarding packaging, storage and transportation marks, packaging marks should comply with the relevant provisions of GB/T6388 and GB191.
8.3 Transportation and storage
8.3.1 The grain cooler should not be collided, tilted or exposed to rain and snow during transportation and storage. 8.3.2 The product should be stored in a dry and well-ventilated warehouse. 1282
A1 Scope of application
JB/T8889-1999
Appendix A
(Appendix to the standard)
Test method for air supply and cooling capacity of grain coolers. For grain coolers with compressor power greater than 2kW, the air flame difference method is used for testing. A2 Air difference method
A2.1 The cooling capacity is determined by measuring the air temperature and wet bulb temperature and air flow rate at the inlet and outlet of the grain cooler. A2.2 The test device is arranged as shown in Figure A1:
Air handling unit
Three return air ducts
A2.3 The test room should meet the requirements of A5.1 according to the actual use. A2.4 The air flow measurement should be in accordance with the provisions of Chapter A3. A2.5 The static pressure measurement outside the machine should be in accordance with the provisions of Chapter A4. A2.6 Temperature Measurement
Test Room
Test Machine
Air Temperature and Humidity
Sampler
A2.6.1 The temperature in the air duct shall be measured at the center of each equal division of the cross section, at least three locations or using a suitable mixer or sampler. Typical mixers and samplers in the air duct are shown in Figure A2. The connecting pipe between the measuring point and the grain cooler shall be insulated, and the heat leakage through the connecting pipe shall not exceed 1.0% of the cooling capacity being measured. A2.6.2 The temperature at the air inlet shall be measured at least three equidistant locations at the air inlet of the grain cooler or using a sampling method with equivalent effect. The temperature measuring instrument or sampler shall be located 150 mm from the air inlet of the grain cooler. A2.6.3 The air velocity passing through the wet bulb temperature measuring instrument shall be about 5 m/s. The same velocity shall be used for the temperature measurement at the air inlet and outlet. Wet bulb temperature measurement for air velocity higher or lower than 5 m/s shall be corrected. A2.7 Calculation of cooling capacity
Test data Calculate cooling capacity according to formula (A1): Where: 9tei—
Cooling capacity, kw;
qtei =Qmi(hal -haz2)/[V',(1 + W,)]Q...…Measured value of air flow, m*/s;han—Heat of air entering grain cooler, kl/kg of dry air,…...(Al)
JB/T88891999
ha2--Heat of air leaving grain cooler, kJ/kg dry air, V\,-.-Specific volume of air at nozzle, m2/kg;WHumidity of air at nozzle, kg/kg dry air. Mixer
A3 Measurement of air flow
A3.1 The air flow shall be measured according to the nozzle device specified in A3.3. A3.2 Nozzle device
Sampler
A3.2.1 The device is shown in Figure A3 and consists of an air inlet chamber and an air outlet chamber separated by a partition, on which one or more nozzles are installed. The air from the grain cooler under test enters the air inlet chamber through the air duct, and is discharged into the test room through the nozzle or returned to the grain cooler inlet by the air duct. A3.2.2 The nozzle device and its connection with the grain cooler outlet should be sealed, and the amount of air leakage should not exceed 1.0% of the measured air flow. A3.2.3 The distance between the centers of the nozzles should not be less than 3 times the throat diameter of the larger nozzle, and the distance from the center of any nozzle to the nearest air chamber or air inlet chamber wall should not be less than 1.5 times the throat diameter of the nozzle. A3.2.4 The installation position of the diffusion baffle in the air inlet chamber should be on the upwind side of the partition, and its distance is at least 1.5 times the throat diameter of the largest nozzle; the installation position in the exhaust chamber should be on the leeward side of the partition, and its distance is at least 2.5 times the throat diameter of the largest nozzle. A3.2.5 A variable air volume exhaust fan should be installed and connected to the exhaust chamber or to a regulating valve for static pressure adjustment. A3.2.6 The static pressure drop through one or several nozzles is measured by one or several pressure gauges. One end of the pressure gauge is connected to the static pressure interface installed on the inner wall of the air inlet chamber and flush with the wall, and the other end is connected to the static pressure interface installed on the inner wall of the exhaust chamber and flush with the wall. Several interfaces in each chamber should be connected in parallel to several pressure gauges or collected and connected to one pressure gauge. According to Figure A3, a Pitot tube can also be used to measure the velocity head of the air flow after leaving the nozzle. When two or more nozzles are used, a Pitot tube should be used to measure the air flow velocity head of each nozzle. A3.2.7 A method for determining the air density at the throat should be provided. A3.3 Nozzle
A3.3.1 The throat velocity of the nozzle when in use should be greater than 15m/s, but less than 35m/s. A3.3.2 The nozzle is manufactured according to the structure of Figure A4 and installed according to the provisions of A3.3. No calibration is required when in use. The flow coefficient of the nozzle with a throat diameter equal to or greater than 127mm can be set as 0.99. If more precise data is required and the flow coefficient of the nozzle with a throat diameter less than 127mm is specified in Table A1, or the nozzle is calibrated.
Air inlet chamber
Different years
Minimum 1D
JB/T8889
Pressure gauge
Minimum 2D
Pitot tube (optional)
Note: The diffusion baffle should have uniform perforations, and the perforation area is about 40% of the flow area. Figure A3
Reynolds number Ne
100000
150000
200000
250000
300000
400000
500000
The Reynolds number is calculated according to formula (A2):
In the formula; NRe Reynolds number;
f——temperature coefficient;
V. Air velocity at the nozzle, m/s;;
D. Nozzle throat diameter, m.
The temperature coefficient f is determined by Table A2.
Nre - fV,D.
Exhaust chamber
Exhaust fan
Volume coefficient C
（A2）
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