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JB/T 6906-1993 Oil-injected screw single-stage refrigeration compressor

Basic Information

Standard: JB/T 6906-1993

tandard name: Oil-injected screw single-stage refrigeration compressor

Standard category:Machinery Industry Standard (JB)

state:in force

release date:1993-07-13

Implementation date:1994-07-01

standard classification number

Standard Classification Number:Machinery>>General Machinery and Equipment>>J73 Refrigeration Equipment

associated standards

Publication information

other information

Focal point unit:Hefei General Machinery Research Institute

Publishing department:Hefei General Machinery Research Institute

Introduction to standards:

This standard specifies the terminology, product classification, technical requirements, test methods, inspection rules, Marking, packaging and storage. This standard applies to open and semi-closed oil-injected screw single-stage refrigeration compressors, oil-injected screw single-stage refrigeration compressor units and economizer oil-injected screw single-stage refrigeration compressors with R22 and R717 as refrigerants and water or air as the cooling medium. stage refrigeration compressor unit. JB/T 6906-1993 Oil-injected screw single-stage refrigeration compressor JB/T6906-1993 Standard download and decompression password: www.bzxz.net

Some standard content:

Machinery Industry Standard of the People's Republic of China
Oil-injected screw single-stage refrigeration compressor
1 Subject and scope of application
JB/T 6906—93
This standard Specifies the terminology, product classification, technical requirements, and testing of oil-injected screw single-stage refrigeration compressors, oil-injected screw single-stage refrigeration compressor units, and economizer oil-injected screw single-stage refrigeration compressor units (hereinafter collectively referred to as "machines") Methods, inspection rules, marking, packaging and storage.
This standard is applicable to open and semi-closed oil-injected screw single-stage refrigeration compressors (hereinafter referred to as "compressors\), oil-injected Screw single-stage refrigeration compressor unit (hereinafter referred to as "compressor unit") and economizer oil-injected screw single-stage refrigeration compressor unit (hereinafter referred to as "economizer compressor unit") 2 Reference standard
GB191 packaging, storage and transportation. Illustrated logo
GB536
Liquid anhydrous ammonia
Basic technical requirements for rotating motors
GB 755
GB1032
Three-phase asynchronous motor Test methods
GB 1348
GH3853
GB 5773
Nodular iron castings
Performance test methods for general positive displacement air compressors Positive displacement refrigeration compressors Performance test method Transportation packaging receipt and delivery mark
GB 6388
GB7373 Industrial difluorochloromethane (Fz2) GB7786
GB10875
Power air compressor and Diaphragm compressor noise sound power level limit technical conditions for medium-sized piston single-stage refrigeration compressor GB/T13306
JB2747
JB4330
label
displacement compressor noise Measurement method
Engineering method for determination of noise and sound power level of refrigeration and air-conditioning equipment JB/T6421 Technical conditions for gray iron castings for refrigeration compressors JB/T6917 Pressure vessels for refrigeration devices
ZBE34003 Refrigeration oil||tt ||Technical conditions for oil-injected screw refrigeration compressor rotor ZB J73 001
ZBJ73028 piston refrigeration compressor cleanliness determination method ZBJ73040 General technical conditions for electrical control equipment of refrigeration compressor units ZBJ73045 technical conditions for screw refrigeration compressor main bearings 3 Terms
3.1 Refrigeration compressor unit
is a refrigeration compressor, motor, transmission device (semi-hermetic refrigeration compressor unit does not have), and ancillary equipment assembled on a public base. Machinery Industry of the People's Republic of China The Ministry approved the implementation of
553
on 1993-07-13 on 1994-07-01. |tt|| is a general term for equipment such as a cooler (supercooler) and a screw compressor unit with a middle air supply hole that are assembled on a common base. The refrigerant vapor of the compressor enters the compression chamber of the compressor through the middle air supply hole of the screw compressor, and mixes with the gas in the compressor to realize the intermediate air supply process, thereby increasing the refrigeration capacity and refrigeration coefficient of the compressor unit under low temperature conditions. (The energy efficiency ratio of the semi-hermetic refrigeration compressor unit is improved. 3.3 The refrigeration coefficient (COP) of the refrigeration compressor. Under specified working conditions, the compressor cooling capacity expressed in the same unit and the unit time are lost to the compression. The energy ratio of the crankshaft.
3.4 ??Energy Efficiency Ratio (EER) wwW.bzxz.Net
Under specified working conditions, the ratio of the cooling capacity of the semi-hermetic refrigeration compressor unit to the input power. It is dimensionless in the SI unit. 4 Product Classification
4.1 Type
4.1.1 The machine can be divided into open type and semi-enclosed type according to the structure type. 4.1.2 The machine can be divided into two types according to the cooling method: water-cooled type and air-cooled type. 4.2 Model
4.2.1 Model representation method
The machine model consists of uppercase Chinese pinyin letters and Arabic numerals (hereinafter referred to as "numbers"), and its representation method is as follows: a.||tt ||b.
Compressor
Modification number: expressed in numbers, omitted for the first designed product Refrigerant type: A-R717; F-R22 (semi-enclosed type is not indicated) Rotor lead: D——short lead; C——long lead; T——extra long lead. Nominal diameter of rotor: expressed in numbers, unit is cm-type; LG——open screw type; BLG
Semi-closed screw type
Compressor unit
Modification number: expressed by numbers, the nominal operating condition is omitted for the first designed product: G high temperature nominal operating condition, Z—medium temperature nominal operating condition; D —— Low temperature nominal working condition
Equipped with motor power: expressed in numbers, the unit is kw. Open type is omitted
—R22 (semi-closed type is not indicated)
Refrigerant type: A ——R717;F—
Nominal diameter of rotor: expressed in numbers, unit is cm type. LG-opening screw type; BLG
c. Economizer compressor unit
554
Semi-closed screw type
4.2.2 model example
a.
Compressor;
JB /T6906--93
-Modification number: expressed by numbers, omitted for the first designed product. Motor power: expressed by numbers, unit is kW. Open type omitted
Refrigerant type: A——R717; F——R22 (semi-closed type is not indicated) Rotor nominal diameter: expressed in numbers, unit is cm Type: LG-open screw type; BLG-semi-closed screw type economizer code
LG16AC : Indicates the nominal diameter of the rotor is 160mm, uses R717 as the refrigerant, long lead open screw single-stage refrigeration BI.G10D2: Indicates the nominal diameter of the rotor is 100mm, uses R22 as the refrigerant, short lead, second modification Semi-hermetic screw b.
Rod single-stage refrigeration compressor;
IG16A100Z2: Indicates that the nominal diameter of the rotor is 160mm, uses R717 as the refrigerant, and is equipped with a motor power of 100.||tt| |kW, the second modified open screw single-stage refrigeration compressor unit used for medium temperature nominal working conditions; BIG12.5-40D1: means the nominal diameter of the rotor is 125mm, using R22 as the refrigerant, and equipped with a motor power of 40kW , d.
The first modified semi-closed screw single-stage refrigeration compressor unit for low-temperature nominal operating conditions: e.JI.G12.5F40-1: Indicates that the nominal diameter of the rotor is 125mm, with R22 Start the screw single-stage refrigeration compressor unit for the refrigerant, equipped with a motor power of 40kW, and the first modified economizer. 5 Technical Requirements
5.1
General Requirements
Products should comply with the provisions of this standard and be manufactured in accordance with drawings and technical documents approved by prescribed procedures, or according to the user and manufacturer manufactured by agreement.
5.2 Basic parameters
5.2.1 The basic parameters of water-cooled open compressors and compressor units should comply with the provisions of Table 1. Table 1
Male rotor speed
r/min
4400
2960
Male rotor
Nominal diameter
mm
100
125
100
125
160
200
250
315|| tt||G
4.65
4, 79
4.56
4.70
4.81
4.95
5.07|| tt | |tt||3.69
3.80
3.89
3.93
D
2.03
2.10
1.98||tt ||2.05
2.10
2.16
2. 21
2.24
z
3.79
3.81||tt ||3.70
3.82
3.96
4.01
4.09
4.14
R717
D
2.13
2.14
2. 08
2.15
2.23
2. 26
2.30
2.33
555
Male rotor speed
r/min
1450
Male rotor
nominal diameter
mm
400
500
G
5.01
5.05
JB/ T 6906--93
Table 1 (End)
Refrigeration coefficient R22 of the refrigeration compressor under nominal operating conditions
D
3.84
3.88|| tt||Note: The shaft power in the refrigeration coefficient of the compressor does not include the power of the separately driven oil pump. 5.2.2 The basic parameters of the water-cooled semi-hermetic compressor unit should comply with the provisions of Table 2. Table 2
Male rotor
Male rotor speed
/min
4400
2960
Nominal diameter
mm| |tt||100
125
100
125
160
G
4.03
4.21||tt ||3.90
4.05
4.21
Note: The input power in the energy efficiency ratio does not include the power of the separately driven oil pump. 2.19
2. 20
z
4.06
4.08
Nominal operating condition energy efficiency ratio
R22
z| |tt||3.10
3.22
3.00
3.11
3.23
The basic parameters of air-cooled open-type compressors and compressor units should comply with Table 3 Provisions. 5.2.31
Table 3
Male rotor speed
r/min
4400
2960
Male rotor
Nominal diameter
mm
100
125
100
125
160
200
R717
D
2.28
2.29
D
1.74
1.82
1.70
1.76|| tt||1.83
The refrigeration coefficient of the refrigeration compressor under nominal operating conditions is R22
G
2.97
3.07
2.91
3. 01
3.08
3.17
Note: The shaft power in the refrigeration coefficient of the refrigeration compressor does not include the power of the separately driven oil pump and fan. 5.2.4 The basic parameters of the air-cooled semi-hermetic compressor unit should comply with the provisions of Table 4. Table 4
Male rotor speed
r/min
4400
556
Nominal diameter of male rotor
mm
100
125
G
2.71
2.82
Nominal working condition energy efficiency ratio
R22
z||tt ||2.28
2.36
2.23
2.31
2.36
2.43
2
1.74
1.81
Male rotor speed
r/min
2960
JB/T 6906—93
Table 4 (End)
Yang Rotor nominal diameter
mm
100
125
160
Note: The input power in the energy efficiency ratio does not include the power of the separately driven oil pump and fan , 5.2.5 The basic parameters of the economizer compressor unit should comply with the following regulations: G
2.60
2.71
2.82
nominal operating condition energy efficiency ratio||tt| |R22
2
1.67
1.74
1.81
The suction pressure saturation temperature is -35℃ and the discharge pressure saturation temperature is +35℃ Under the working conditions, the cooling capacity of the economizer compressor unit a.
should be increased by more than 20% than the cooling capacity of the compressor unit without an economizer of the same model, b. Under the working condition that the suction pressure saturation temperature is -35°C and the discharge pressure saturation temperature is +35°C, the refrigeration coefficient of the refrigeration compressor of the economizer compressor unit (semi-hermetic compressor unit is the energy efficiency ratio) should be higher than that of the same model. The compressor unit with economizer increases by more than 12%. 5.3 Design and usage conditions
The design and usage conditions of the machine should comply with the provisions of Table 5. Table 5
Refrigerant
Cooling method
Maximum discharge pressure saturation temperature
Minimum suction pressure saturation temperature
Maximum suction pressure saturation temperature|| tt||Maximum exhaust temperature
Note: The discharge pressure is the pressure before the oil separator. 5.4 Nominal operating conditions
5.4.1
Water
49
Ling
40
Nominal operating conditions of compressors and compressor units According to the provisions of Table 6. R22
10
Table 6
nominal operating conditions
high temperature
medium temperature
low temperature
refrigerant||tt ||R22
R717
R22
R717
suction pressure
saturation temperature
7
7|| tt||23
Inhalation temperature
18
1
15
Wind
60
20|| tt||105
Discharge pressure saturation temperature
Water cooling
43
35
Air cooling
55
R717
Water
46
Ling
40
5
Refrigerant liquid temperature
ling
Water
38
30


Air cooling
50
5.4.2 Economizer compressor unit Except for the suction pressure saturation temperature of 35°C, the nominal operating conditions are the same as the low-temperature nominal operating conditions of the compressor and compressor unit.
5.5 Refrigeration capacity deviation
When the machine cooling capacity is less than or equal to 120kW, the allowable deviation between the actual measured cooling capacity and the designed cooling capacity is 7%: When the machine cooling capacity is greater than 120kW, the allowed deviation between the measured cooling capacity and the designed cooling capacity The allowable deviation of the quantity is -5%. The cooling capacity includes the cooling capacity obtained by superheating the refrigerant vapor on the suction pipe. 557
JB/T 6906-93
5.6 Refrigeration compressor refrigeration coefficient deviation and energy efficiency ratio deviation Under nominal operating conditions, the refrigeration coefficient of open compressors and compressor units should not be lower than the table below 1. 95% of the specified value in Table 3. The energy efficiency ratio of the semi-hermetic compressor unit should not be less than 95% of the values ??specified in Table 2 and Table 4. 5.7 Refrigerant
The R22 refrigerant used in the machine should comply with the regulations of GB7373, and the R717 refrigerant should comply with the regulations of GB536. 5.8 Lubricating oil
5.8.1 The lubricating oil used in the machine should comply with the regulations of ZBE34003. 5.8.2 When the lubricating oil used for semi-hermetic compressor units and economizer compressor units is spaced at 2.5mm and the oil temperature is 25C, the withstand voltage and insulation performance should not be less than 25kV.
5.9 Exhaust temperature and oil temperature
5.9.1 When the cooling water temperature is not higher than 32C, the machine's exhaust temperature and cooled oil temperature should comply with the provisions of Table 7. Table 7
Refrigerant
R22.R717
5.9.2 The oil temperature should not be lower than 25℃ when the machine is started. 5.10 Power supply voltage deviation
Exhaust temperature
105
Oil
Temperature
30~65
When the power supply voltage deviation is the rated value When 10% to 105%, it should be ensured that the machine can start and operate normally. 5.11 Noise value
The noise value of the machine under nominal working conditions (the average of the total sound pressure level) should not be greater than the requirements in Table 8. Table 8
Male rotor speed
r/min
Nominal diameter of the male rotor
mm
Rotor aspect ratio
Open type| |tt||Semi-enclosed
5.12 vibration value
100
4400
1.5
82
77
84
125
1.5
86
791 81
88
83
80
100
1.5
82
75
77
When the machine is fixed on the base, the vibration value should be below 25um. 5.13 Cleanliness
125
1.5
84
79
86
81
160
2960
200
1.5
89
83
85
5.13.1 The inside of the machine should be clean, and the suction port should be equipped with gas Filter to ensure the cleanliness of the suction gas. 5.13.2 The cleanliness of the compressor should not exceed the requirements of Table 9. Table 9
Nominal diameter of the male rotor
mm
The long diameter of the rotor Than
Cleanliness
mg
100
1.5
740
800
125
1.5
860
940
160
1.5
91
200
1.5
1.5|| tt||93
250
11.5
96
250
99
1.5
C||tt| |dB(A)
315
1.5
101
104
315
1.5
1100011001200|130014001500160017005.13. 3. The cleanliness per unit area of ??the oil cooler, oil separator, oil reservoir, economizer cooler and connecting pipes of the compressor unit, economizer compressor unit should not exceed 800mg/m2 for R717 and 400mg/m2 for R22. Among them, the oil cooler and economizer cooler are calculated according to their heat exchange area, and the oil separator, oil reservoir and connecting pipes are calculated according to their inner surface area. 558
5.14·Amount of oil leakage
JB/T 6906—93
The machine should be airtight and should not leak refrigerant. When the open machine is running, there should be no leakage of refrigerant at the shaft seal. The amount of oil leakage should not be greater than 3mL/h. 5.15 Energy adjustment device
5.15.1 When the machine is equipped with an energy adjustment device, the action of the energy adjustment device should be sensitive and reliable. 5.15.2 The cooling capacity adjustment range of the machine energy adjustment device is 15%~~100%. 5.16 Lubrication system
5.16.1 The lubrication system should have a reliable oil supply and be equipped with an oil filter to ensure clean oil supply. 5.16.2 Machines using R22 refrigerant should also be equipped with electric heaters to ensure reliable oil supply when starting the compressor in winter. 5.17 Pressure resistance and air tightness requirements
5.17.1 The compressor body, suction end seat, exhaust end seat, suction end cover, exhaust end cover and other air chambers that are in contact with the refrigerant should be hydraulically and airtightly The test lasts for 5 minutes each and there should be no leakage. The hydraulic test pressure should be 1.5 times the design pressure of the machine body, and the air-tight test pressure should be equal to the design pressure.
5.17.2 The refrigerant side of the motor housing of semi-hermetic compressor units and economizer compressor units shall undergo hydraulic and air tightness tests for 5 minutes each and shall not leak. The hydraulic test pressure should be 1.5 times the design pressure of the compressor body; the air tightness test pressure should be equal to the design pressure. 5.18 Technical requirements for compressor parts and components
5.18.1 Consumable parts should ensure that parts of the same model and specification can be interchanged. 5.18.2 The rotor shall comply with the requirements of ZBJ73001. 5.18.3 The main bearing should comply with the requirements of ZBJ73045. 5.18.4 Other parts and components should comply with the requirements of corresponding standards. 5.19 Motor
5.19.1 Motors for open machines should comply with the regulations of GB755 and GB1032. 5.19.2 The motors used in semi-hermetic compressor units and economizer compressor units shall comply with the provisions of Appendix B of GB10875. 5.20 Check valve
Check valves should be installed at the suction and exhaust ends of the machine, and their opening and closing should be sensitive and reliable. 5.21 Oil separator, oil cooler, oil reservoir and economizer cooler 5.21.1 The oil separator, oil cooler, oil reservoir and economizer cooler of the machine shall comply with the provisions of the corresponding standards. 5.21.2 Oil separation The device should be able to effectively separate oil. 5.22 Pressure vessels
The pressure vessels used in machines should comply with the regulations of JB/T6917. 5.23 Electrical equipment and instruments
5.23.1 Machines equipped with automatic control should have manual control mechanisms. 5.23.2 The electrical equipment of the machine should be reliably grounded. 5.23.3 The manufacturing of the control cabinet supporting the machine should comply with the requirements of ZBJ73040. 5.24 Technical requirements for castings
5.24.1 Gray cast iron parts should comply with the regulations of JB/T6421. 5.24.2 Ductile iron parts should comply with the regulations of GB1348. 5.24.3 Cast iron parts such as the machine body, suction end seat, exhaust end seat, suction end cover, exhaust end cover, slide valve and other cast iron parts should be aged. 5.25 Safety protection
The protection items of the machine should at least include:
main motor overload protection;
a.
b. High and low pressure protection;
c.
Oil pressure difference protection.
5.26 Appearance quality
559
JB/T 6906—93
The machine should be beautiful and elegant, the casting surface should be smooth and flat, the paint color should be harmonious and durable, and the pipeline should be Connections should be simple and neat. 5.27 Reliability requirements
5.27.1 The trouble-free operation requirements of the machine shall comply with the relevant reliability standards. 5.27.2 The mean time between failures (MTBF) of the machine should be no less than 15000h. 5.28 Supporting equipment
Machines supplied in complete sets should generally include: a: Host: compressor, main motor;
b. Ancillary equipment: oil separator, oil cooler, economizer cooler (equipped with economizer compressor unit), compressor internal piping system, lubrication system.
5.29 Quality Guarantee Period
Provided that the user abides by the rules of transportation, storage, installation and use of the product, within 18 months from the date of shipment from the manufacturer, and the actual working time of the machine does not exceed After more than 8000 hours, if the product is damaged or cannot work properly due to poor manufacturing (except wearing parts), the manufacturer should replace or repair it free of charge.
6 Test methods
6.1 Pressure test
6.1.1 Pressure resistance test
6.1.1.1 Pressure resistance test medium is a clean liquid with a temperature of not less than 5℃. 6.1.1.2 After filling the tested part with liquid and removing the air, slowly pressurize it to the test pressure. There should be no leakage or abnormal deformation. 6.1.2 Air tightness test | Close test. 6.1.2.2 The air tightness test medium is dry clean air or nitrogen with a temperature not lower than 5°C. 6.1.2.3 During the air tightness test, place the subject into a pool with a temperature of no less than 15C (the water should be clean and transparent) or apply foaming liquid to the outside. The gas pressure slowly rises to the test pressure and there should be no leakage. 6.1.3 Pressure gauge accuracy
The pressure test should use two calibrated pressure gauges with the same range. The range of the pressure gauge should be 1.52 times the test pressure, the diameter of the dial should not be less than 100mm, and the accuracy should not be less than level 1.5. 6.2 Electrical performance test of semi-hermetic compressor unit and economizer compressor unit 6.2.1 Insulation resistance test
Under the conditions of normal temperature or relative humidity less than or equal to 80%, use a 500V insulation resistance meter to measure the insulation resistance of the semi-hermetic compressor unit and economizer compressor unit terminal to the shell, and its value Should be no less than 5MQ. 6.2.2 Electrical strength test
Use a high-voltage test bench with a capacity of not less than 0.5kVA to apply 50Hz, sine wave AC voltage 1000V plus 2 times between the terminals and the shell of the semi-hermetic compressor unit, economizer compressor unit voltage, for 1 minute, there should be no breakdown or flashover. For semi-hermetic compressor units and economizer compressor units that have already undergone electrical strength testing, if electrical strength testing must be carried out again, the test voltage should be reduced by 20%. 6.3 Action test of electrical appliances and control components
Conduct an action test on the electrical appliances and control components of the machine. Their actions should be sensitive and reliable. 6.4 Refrigeration capacity test under nominal working conditions
Under rated voltage and frequency, the machines shall determine their cooling capacity and shaft power under nominal working conditions (semi-hermetic compressor unit, economizer compressor unit) according to the method specified in GB5773 is the input power), the refrigeration coefficient of the refrigeration compressor (semi-hermetic compressor unit, economizer compressor unit is the energy efficiency ratio) and other values.
6.5 Part-load operation test
Machines with energy adjustment devices should undergo 25%, 50%, and 75% three-level partial load operation tests to measure their performance under nominal operating conditions 560||tt| Refrigeration capacity and shaft power of |JB/T 6906—93
(semi-hermetic compressor unit and economizer compressor unit are input power). 6.6 Full performance test
The full performance curve chart should be provided when the machine passes the test. The full performance curve chart should include no less than three different condensation temperatures, and no less than five evaporation temperatures of cooling capacity and shaft power (semi-hermetic compressor unit, economizer compressor unit) at each condensation temperature. is the input power), the refrigeration coefficient of the refrigeration compressor (the energy efficiency ratio of the semi-hermetic compressor unit and the economizer compressor unit), the gas transmission coefficient, etc., which should include the test operating points specified in Table 12. 6.7 Noise measurement
The noise of the machine under nominal working conditions shall be measured according to the method specified in JB2747 or the sound power level shall be measured according to the method specified in JB4330, and then converted into sound pressure level according to the regulations in Appendix A of GB7786, and the measurement results Should comply with the provisions of Article 5.11. 6.8 Cleanliness measurement
6.8.1 The cleanliness of the compressor should refer to the regulations of ZBJ73028, and the sampling location should be as specified in Table 10. Table 10
Name
Name
Suction and exhaust end covers and suction and exhaust end seats
Body
Rotor and bearings||tt| |Slide valve parts
Refrigerating oil
Sampling parts
All internal surfaces and pores
All surfaces and pores
Collect all refrigeration accumulated in the body, etc. Engine oil 6.8.2 The cleanliness of the compressor unit and economizer compressor unit is measured by disassembling and cleaning the special refrigerant liquid pipeline drying filter (100um filter) after the type inspection or sampling inspection, and weighing the weight of the impurities contained therein. That is the cleanliness of the compressor unit or economizer compressor unit.
6.8.3 The cleanliness of the machine shall comply with the provisions of Article 5.13. 6.9 Determination of vibration value
The method of measuring the vibration value of the machine is in accordance with the provisions of Appendix A (reference part). 6.10 Mechanical operation test and exhaust volume measurement The mechanical operation test and exhaust volume measurement of the machine can be carried out at the same time. The exhaust volume is measured according to the method specified in GB3853. When the machine is running, check whether it is running smoothly and whether there are any abnormal sounds. and severe vibration, check whether there is any abnormal temperature rise on the outer surface of the main bearing and the outer surface of the shaft seal.
7 Inspection Rules
7.1 General Requirements
The parts, components and entire machine of the machine shall be inspected by the quality inspection department of the manufacturer in accordance with this standard and technical documents. Factory ready.
7.2 Inspection regulations
7.2.1 Inspection classification
The inspection of machines is divided into three types: factory inspection, type inspection and sampling inspection. 7.2.2 Inspection items
The inspection items of the machine should be as specified in Table 11. 561
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