
JB/T 6918-1993 Metal and glass sintered liquid level gauges and sight glasses for refrigeration
time:
1993-07-13 15:00:00
- JB/T 6918-1993
- Abolished
Standard ID:
JB/T 6918-1993
Standard Name:
Metal and glass sintered liquid level gauges and sight glasses for refrigeration
Chinese Name:
制冷用金属与玻璃烧结液位计和视镜
Standard category:
Machinery Industry Standard (JB)
-
Date of Release:
1993-07-13 -
Date of Implementation:
1994-07-01 -
Date of Expiration:
2005-04-01
China Standard Classification Number:
Machinery>>General Machinery and Equipment>>J73 Refrigeration Equipment
alternative situation:
Replaced by JB/T 6918-2004

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Summary:
JB/T 6918-1993 Metal and glass sintered liquid level gauge and sight glass for refrigeration JB/T6918-1993 Standard download and decompression password: www.bzxz.net

Some standard content:
Machinery Industry Standards of the People's Republic of China
Metal and glass sintering for refrigeration
Liquid level gauges and sight glasses
1 Subject content and scope of application
JB/T 6918 - 93
This standard specifies the types and basic parameters, technical requirements, test methods, Inspection rules and marking, packaging and storage. This standard is recommended for liquid level gauges and sight glasses for refrigerators and other pressure vessels with operating temperatures ranging from 40 to 180°C and design pressures not higher than 3.0MPa.
2 reference standards
Ordinary thread tolerance and fit (diameter 1~355mm) GB 1971
GB539i
Oil-resistant asbestos rubber sheet
Carbon structural steel | |tt | Blue type
QB776 glass plate and glass tube for liquid level meter
3 types and basic parameters
Liquid level meter is divided into tube type and plate type; sight glass Divided into flange type and thread type. 3.2 Model
3.2.1 Model representation method
口口口
The improved design serial number is represented by A, BC·
The liquid level gauge can observe the liquid level length or visual Hole diameter: expressed in Arabic numerals, mm type code: YG is tubular type, YB is plate level gauge, SF is flange type, SL is threaded sight glass metal and glass sintering code
3.2.2 model Example
JYG-120: Metal and glass sintered tube liquid level gauge, the observable liquid level length is 120mm. JSI.-45A: Metal and glass sintered threaded sight glass, sight hole diameter 45mm, the first improved design. 3.3 Basic parameters
Ministry of Machinery Industry of the People's Republic of China approved 1344 on 1993-07-13
Implemented on 1994-07-01
JB/T 6918—93
Liquid level The basic parameters of the meter and sight glass are shown in Appendix A (reference part) or manufactured according to the agreement between the manufacturer and the user. 4 Technical Requirements
4.1 Liquid level gauges and sight glasses shall comply with the provisions of this standard and be manufactured according to drawings and technical documents approved by prescribed procedures (or according to an agreement). 4.2 The glass of the liquid level gauge and sight glass should comply with the requirements of QB776. 4.3 The mechanical properties of the metal material sintered with the lens should not be lower than the requirements of Q235A carbon steel in GB700. 4.4 Surface roughness and dimensional tolerance
The surface roughness and dimensional tolerance are specified as follows: a. Surface roughness R of the sealing surface of the liquid level gauge and sight glass. is 3.2μm; the accuracy level of the connecting thread should comply with the 6H or 6h level specified in GB197. b.
4.5 Appearance requirements for liquid level gauges and sight glass lenses
The appearance requirements for liquid level gauges and sight glass lenses are as follows: The lenses should be transparent and colorless, or slightly light yellow: a.|| tt||There should be no obvious filamentous and comb-like stripes on the lens; b..
There should be no opaque impurities on the lens;
There should be no cracks and obvious scratches on the lens; d.
There should be no bubbles in the center of the lens and no bubbles on the edges ( There should be no dense air bubbles or scattered air bubbles exceeding the specified size (within 2mm from the joint surface). e.
The maximum size of dense bubbles should not be larger than 0.5mm, and the area should not be larger than 3mm2; there should be no more than 3 dispersed bubbles of 0.5~1.5mm in an area of ??40mm2.
4.6 Pressure test
4.6.1 Hydraulic test
Carry out the test according to the method specified in 5.2.1. There should be no cracks or leaks between the lens and the joint surface. 4.6.2 Air pressure test
The test piece can also use the method specified in Article 5.2.2 instead of the test in Article 4.6.1. There should be no cracks or leaks between the lens and the joint surface. 4.6.3 Design strength hydraulic verification test
Carry out the test according to the method specified in Article 5.2.3. The lens should not be broken, and there should be no cracks or leaks between the lens and the joint surface. 4.7 Air tightness test
Carry out the test according to the method specified in Article 5.3. There should be no cracks or leaks. 4.8 Thermal Stability Test
Carry out the test according to the method specified in Article 5.4. The lens should not be broken, and there should be no cracks between the lens and the joint surface. 4.9 Other requirements
4.9.1 The stop valve used for tubular liquid level gauges should comply with the relevant refrigeration valve requirements, and the liquid valve should be equipped with a safety protection steel ball. 4.9.2 When the tubular liquid level meter is connected with a flange, the flange size shall be manufactured according to the user's requirements or the regulations of GB9112. 4.9.3 The gasket material should comply with the regulations of GB539. 4.9.40 type rubber ring should have good compatibility with refrigerant, refrigeration oil, etc., and the size and technical requirements should comply with the regulations of GB3452.1. 5 Test methods
5.1 Appearance inspection
The appearance of the lens shall be inspected visually with a 5x magnifying glass and shall comply with the provisions of Article 4.5. 5.2 Pressure test
5.2.1 Hydraulic test
Install the liquid level gauge or sight glass on a special test device. The test medium is clean water or lubricating oil. The accuracy of the pressure gauge should not be less than 1.5 level, and use two calibrated pressure gauges with the same range (the range is preferably about 2 times the test pressure) and within the validity period. During the test, the pressure is slowly raised to 1.5 times the design pressure at a speed of no more than 0.1MPa per second, and the pressure is maintained for 3 minutes. It should comply with the provisions of Article 4.6.1. 1345
5.2.2 Air pressure test
JB/T 6918—93
Install the liquid level gauge or sight glass on a special test device. The test medium is clean air or nitrogen. The pressure The table requirements are the same as those specified in Article 5.2.1, and safety protection measures should be taken during the test. During the test, slowly increase the pressure to 1.25 times the design pressure at a speed of no more than 1.0MPa per minute, maintain the pressure for 1 minute, then reduce the pressure to the design pressure, and then use the foaming liquid or immersion method to check. It should comply with Article 4.6.2 Regulation. 5.2.3 Design strength hydraulic verification test
Slowly pressurize the test piece to the design pressure according to the method specified in Article 5.2.1, and then release the pressure to zero; then slowly pressurize it to 2.0 times the design pressure. Then release the pressure to zero, and finally slowly increase the pressure to 3.0 times the design pressure, and keep the pressure for 5 minutes. After checking and confirming that it meets the requirements of Article 4.6.3, conduct an air tightness test according to Article 5.3. It should comply with the provisions of Article 4.7. . 5.3 Air tightness test
Slowly pressurize the test piece to the design pressure according to the method specified in Article 5.2.2, keep the pressure for 1 minute, and check with foaming liquid or immersion method. It should comply with Article 4.7 Regulation. If it passes the inspection according to Article 4.6.2, this test does not need to be done. 5.4 Thermal stability test
Place the liquid level gauge or sight glass in an electric furnace, keep it at a temperature of no less than 180°C for 15 minutes, take it out, and immediately put it into a 40°C dry ice bath container. Repeat the test 5 times. , each time interval shall not be less than 30 minutes and shall comply with the provisions of Article 4.8. The air tightness test shall be carried out according to the provisions of Article 5.3 and shall comply with the provisions of Article 4.7. 6 Inspection Rules
General Requirements
Products must be inspected by the quality inspection department of the manufacturer in accordance with this standard and corresponding standards and technical documents before leaving the factory. 6.2 Factory inspection
After passing the inspection according to Articles 4.4 and 4.5, the items shall pass the inspection one by one according to Articles 4.6.1 and 4.7 or Article 4.6.2. 6.3 Type inspection
6.3.1 Type inspection shall be carried out when one of the following situations occurs: a.
Trial products of each model:
b. When there are major changes in the product design, process, and materials of each model; c. After half a year of continuous production.
6.3.2 Batch
Liquid level gauges or sight glasses of the same material and type manufactured in the same furnace in the same shift are considered to be one batch. 6.3.3 Sampling method
Randomly sample 10 pieces from each batch of products.
6.3.4 First, the inspection should be qualified according to Articles 4.4, 4.5 and 4.7, and then 4 pieces will be selected from the 10 pieces and divided into two groups, which shall be inspected according to Articles 4.6.3 and 4.8 respectively.
6.3.5 All products inspected should be qualified. If there are unqualified products, they will be dealt with according to the provisions of the following table. Inspection content
Article 4.6.3
4.8 pieces
Inspection results
1 unqualified
2 unqualified
1 unqualified each
1 Pieces unqualified
2 pieces unqualified
Duplex
Double
Double
Inspection
Times|| tt||Re-inspection results
All qualified
1 unqualified
All qualified
1 unqualified
Conclusion
Qualified
Discarded
Qualified
Discarded
Marking, packaging, transportation and storage
Liquid The position meter and sight glass should have the following marks:
Model number:
Manufacturer name and trademark;| |tt||Specifications;
Design pressure;
Manufacturing year, month or batch number.
JB/T 6918-93
2 The liquid level gauge and sight glass should be packed in cartons stuffed with paper flowers or plastic materials, and the lenses should be protected by cardboard or film. There should be product 7.2
certificate and product instructions in the packaging box.
The liquid level gauge and sight glass should be installed and handled with care to prevent heavy pressure and collision, and should be stored in a dry place free of acid and alkali corrosion. 7.3
JB/T 6918 -- 93
Appendix A
Basic parameters of liquid level gauge and sight glass
(reference part)|| The basic parameters of tt||A1 tube level gauge are shown in Figure A1 and Table A1. 1
Hedpoel
Figure A1
Table A1
Tank installation
Liquid level counting|| tt||&
TYG-120
TYG-220
TYG -320
TYG-620
TYG-920
TYG-1 220
TYG-1520
height
1||tt ||300
observable liquid level|| tt||Length
1220||tt| |1520
Outer diameter
Inner diameter
Thickness
Connecting nut
Connection size
Outer diameter × wall thickness
Globe valve|| tt||DN
JB/T6918-93
The basic parameters of A2 plate level gauge are shown in Figure A2 and Table A2. Bolts
Figure A2
Table A2
JYB-120
JYB-170
JYB- 200
JYB-220
JYB-320
observable liquid level length
356| |tt||Connection size
The basic parameters of A3 threaded sight glass are shown in Figure A3 and Table A3 Ln/n|| tt||74/2
Figure A3
Bolt hole
10—9
12--11
14--11
16—| |tt||-11
Length
Dimensions
16|| tt||1349
JSL-20
JSL-27
JSL-39
JSL-45|| tt||View hole diameter
JB/T6918—93||tt| |Table A3
Straight
Diameter
M52×2
M60X2||tt ||The basic parameters of the A4 flange sight glass are shown in Figure A4 and Table A4. De
Figure A4
Table A4
View hole diameter
JSF-28| |tt||JSF-45
JSF-50
JSF-80
JSF-125
JSF-150
Additional notes: ||tt ||D.
bolt hole distribution circle
Diameter
Outer diameter
bolt hole Number
(uniformly distributed)
10||tt| |This standard is proposed and administered by the Hefei General Machinery Research Institute of the Ministry of Machinery Industry. Connecting nut
Bolt hole diameter
This standard is approved by Hefei General Machinery Research Institute and Changzhou Chenghexiang Hardware Machinery Factory Responsible for drafting. The main drafters of this standard: Ren Jinlu and Gu Longfei. 1350
Thickness
Length
10| |tt||16
Degree
O-ring specifications
Inner diameter×section diameter
32. 5× 2. 65
51.5×2.65
92.5×3.55
129.4×5.7
154.3X5.7
Manufacturing year, month or batch number.
JB/T 6918-93
2 The liquid level gauge and sight glass should be packed in cartons stuffed with paper flowers or plastic materials, and the lenses should be protected by cardboard or film. There should be product 7.2
certificate and product instructions in the packaging box.
The liquid level gauge and sight glass should be installed and handled with care to prevent heavy pressure and collision, and should be stored in a dry place free of acid and alkali corrosion. 7.3
JB/T 6918 -- 93
Appendix A
Basic parameters of liquid level gauge and sight glass
(reference part)|| The basic parameters of tt||A1 tube level gauge are shown in Figure A1 and Table A1. 1
Hedpoel
Figure A1
Table A1
Tank installation
Liquid level counting|| tt||&
TYG-120
TYG-220
TYG -320
TYG-620
TYG-920
TYG-1 220
TYG-1520
height
1||tt ||300
observable liquid level|| tt||Length
1220||tt| |1520
Outer diameter
Inner diameter
Thickness
Connecting nut
Connection size
Outer diameter × wall thickness
Globe valve|| tt||DN
JB/T6918-93
The basic parameters of A2 plate level gauge are shown in Figure A2 and Table A2. Bolts
Figure A2
Table A2
JYB-120bZxz.net
JYB-170
JYB- 200
JYB-220
JYB-320
observable liquid level length
356| |tt||Connection size
The basic parameters of A3 threaded sight glass are shown in Figure A3 and Table A3 Ln/n|| tt||74/2
Figure A3
Bolt hole
10—9
12--11
14--11
16—| |tt||-11
Length
Dimensions
16|| tt||1349
JSL-20
JSL-27
JSL-39
JSL-45|| tt||View hole diameter
JB/T6918—93||tt| |Table A3
Straight
Diameter
M52×2
M60X2||tt ||The basic parameters of the A4 flange sight glass are shown in Figure A4 and Table A4. De
Figure A4
Table A4
View hole diameter
JSF-28| |tt||JSF-45
JSF-50
JSF-80
JSF-125
JSF-150
Additional notes: ||tt ||D.
bolt hole distribution circle
Diameter
Outer diameter
bolt hole Number
(uniformly distributed)
10||tt| |This standard is proposed and administered by the Hefei General Machinery Research Institute of the Ministry of Machinery Industry. Connecting nut
Bolt hole diameter
This standard is approved by Hefei General Machinery Research Institute and Changzhou Chenghexiang Hardware Machinery Factory Responsible for drafting. The main drafters of this standard: Ren Jinlu and Gu Longfei. 1350
Thickness
Length
10| |tt||16
Degree
O-ring specifications
Inner diameter×section diameter
32. 5× 2. 65
51.5×2.65
92.5×3.55
129.4×5.7
154.3X5.7
Manufacturing year, month or batch number.
JB/T 6918-93
2 The liquid level gauge and sight glass should be packed in cartons filled with paper flowers or plastic materials, and the lenses should be protected by cardboard or film. There should be product 7.2
certificate and product instructions in the packaging box.
The liquid level gauge and sight glass should be installed and handled with care to prevent heavy pressure and collision, and should be stored in a dry place free of acid and alkali corrosion. 7.3
JB/T 6918 -- 93
Appendix A
Basic parameters of liquid level gauge and sight glass
(reference part)|| The basic parameters of tt||A1 tube level gauge are shown in Figure A1 and Table A1. 1
Hedpoel
Figure A1
Table A1
Tank installation
Liquid level counting|| tt||&
TYG-120
TYG-220
TYG -320
TYG-620
TYG-920
TYG-1 220
TYG-1520
height
1||tt ||300
observable liquid level|| tt||Length
1220||tt| |1520
Outer diameter
Inner diameter
Thickness
Connecting nut
Connection size
Outer diameter × wall thickness
Globe valve|| tt||DN
JB/T6918-93
The basic parameters of A2 plate level gauge are shown in Figure A2 and Table A2. Bolts
Figure A2
Table A2
JYB-120
JYB-170
JYB- 200
JYB-220
JYB-320
observable liquid level length
356| |tt||Connection size
The basic parameters of A3 threaded sight glass are shown in Figure A3 and Table A3 Ln/n|| tt||74/2
Figure A3
Bolt hole
10—9
12--11
14--11
16—| |tt||-11
Length
Dimensions
16|| tt||1349
JSL-20
JSL-27
JSL-39
JSL-45|| tt||View hole diameter
JB/T6918—93||tt| |Table A3
Straight
Diameter
M52×2
M60X2||tt ||The basic parameters of the A4 flange sight glass are shown in Figure A4 and Table A4. De
Figure A4
Table A4
View hole diameter
JSF-28| |tt||JSF-45
JSF-50
JSF-80
JSF-125
JSF-150
Additional notes: ||tt ||D.
bolt hole distribution circle
Diameter
Outer diameter
bolt hole Number
(uniformly distributed)
10||tt| |This standard is proposed and administered by the Hefei General Machinery Research Institute of the Ministry of Machinery Industry. Connecting nut
Bolt hole diameter
This standard is approved by Hefei General Machinery Research Institute and Changzhou Chenghexiang Hardware Machinery Factory Responsible for drafting. The main drafters of this standard: Ren Jinlu and Gu Longfei. 1350
Thickness
Length
10| |tt||16
Degree
O-ring specifications
Inner diameter×section diameter
32. 5× 2. 65
51.5×2.65
92.5×3.55
129.4×5.7
154.3X5.7
JB/T 6918 -- 93
Appendix A
Basic parameters of liquid level gauge and sight glass
(reference part)|| The basic parameters of tt||A1 tube level gauge are shown in Figure A1 and Table A1. 1
Hedpoel
Figure A1
Table A1
Tank installation
Liquid level counting|| tt||&
TYG-120
TYG-220
TYG -320
TYG-620
TYG-920
TYG-1 220
TYG-1520
height
1||tt ||300
observable liquid level|| tt||Length
1220||tt| |1520
Outer diameter
Inner diameter
Thickness
Connecting nut
Connection size
Outer diameter × wall thickness
Globe valve|| tt||DN
JB/T6918-93
The basic parameters of A2 plate level gauge are shown in Figure A2 and Table A2. Bolts
Figure A2
Table A2
JYB-120
JYB-170
JYB- 200
JYB-220
JYB-320
observable liquid level length
356| |tt||Connection size
The basic parameters of A3 threaded sight glass are shown in Figure A3 and Table A3 Ln/n|| tt||74/2
Figure A3
Bolt hole
10—9
12--11
14--11
16—| |tt||-11
Length
Dimensions
16|| tt||1349
JSL-20
JSL-27
JSL-39
JSL-45|| tt||View hole diameter
JB/T6918—93||tt| |Table A3
Straight
Diameter
M52×2
M60X2||tt ||The basic parameters of the A4 flange sight glass are shown in Figure A4 and Table A4. De
Figure A4
Table A4
View hole diameter
JSF-28| |tt||JSF-45
JSF-50
JSF-80
JSF-125
JSF-150
Additional notes: ||tt ||D.
bolt hole distribution circle
Diameter
Outer diameter
bolt hole Number
(uniformly distributed)
10||tt| |This standard is proposed and administered by the Hefei General Machinery Research Institute of the Ministry of Machinery Industry. Connecting nut
Bolt hole diameter
This standard is approved by Hefei General Machinery Research Institute and Changzhou Chenghexiang Hardware Machinery Factory Responsible for drafting. The main drafters of this standard: Ren Jinlu and Gu Longfei. 1350
Thickness
Length
10| |tt||16
Degree
O-ring specifications
Inner diameter×section diameter
32. 5× 2. 65
51.5×2.65
92.5×3.55
129.4×5.7
154.3X5.7
JB/T 6918 -- 93
Appendix A
Basic parameters of liquid level gauge and sight glass
(reference part)|| The basic parameters of tt||A1 tube level gauge are shown in Figure A1 and Table A1. 1
Hedpoel
Figure A1
Table A1
Tank installation
Liquid level counting|| tt||&
TYG-120
TYG-220
TYG -320
TYG-620
TYG-920
TYG-1 220
TYG-1520
height
1||tt ||300
observable liquid level|| tt||Length
1220||tt| |1520
Outer diameter
Inner diameter
Thickness
Connecting nut
Connection size
Outer diameter × wall thickness
Globe valve|| tt||DN
JB/T6918-93
The basic parameters of A2 plate level gauge are shown in Figure A2 and Table A2. Bolts
Figure A2
Table A2
JYB-120
JYB-170
JYB- 200
JYB-220
JYB-320
observable liquid level length
356| |tt||Connection size
The basic parameters of A3 threaded sight glass are shown in Figure A3 and Table A3 Ln/n|| tt||74/2
Figure A3
Bolt hole
10—9
12--11
14--11
16—| |tt||-11
Length
Dimensions
16|| tt||1349
JSL-20
JSL-27
JSL-39
JSL-45|| tt||View hole diameter
JB/T6918—93||tt| |Table A3
Straight
Diameter
M52×2
M60X2||tt ||The basic parameters of the A4 flange sight glass are shown in Figure A4 and Table A4. De
Figure A4
Table A4
View hole diameter
JSF-28| |tt||JSF-45
JSF-50
JSF-80
JSF-125
JSF-150
Additional notes: ||tt ||D.
bolt hole distribution circle
Diameter
Outer diameter
bolt hole Number
(uniformly distributed)
10||tt| |This standard is proposed and administered by the Hefei General Machinery Research Institute of the Ministry of Machinery Industry. Connecting nut
Bolt hole diameter
This standard is approved by Hefei General Machinery Research Institute and Changzhou Chenghexiang Hardware Machinery Factory Responsible for drafting. The main drafters of this standard: Ren Jinlu and Gu Longfei. 1350
Thickness
Length
10| |tt||16
Degree
O-ring specifications
Inner diameter×section diameter
32. 5× 2. 65
51.5×2.65
92.5×3.55
129.4×5.7
154.3X5.7
stop valve
JB/T6918—93
The basic parameters of A2 plate level gauge are as follows Shown in Figure A2 and Table A2. Bolts
Figure A2
Table A2
JYB-120
JYB-170
JYB- 200
JYB-220
JYB-320
observable liquid level length
356| |tt||Connection size
The basic parameters of A3 threaded sight glass are shown in Figure A3 and Table A3 Ln/n|| tt||74/2
Figure A3
Bolt hole
10—9
12--11
14--11
16—| |tt||-11
Length
Dimensions
16|| tt||1349
JSL-20
JSL-27
JSL-39
JSL-45|| tt||View hole diameter
JB/T6918—93||tt| |Table A3
Straight
Diameter
M52×2
M60X2||tt ||The basic parameters of the A4 flange sight glass are shown in Figure A4 and Table A4. De
Figure A4
Table A4
View hole diameter
JSF-28| |tt||JSF-45
JSF-50
JSF-80
JSF-125
JSF-150
Additional notes: ||tt ||D.
bolt hole distribution circle
Diameter
Outer diameter
bolt hole Number
(uniformly distributed)
10||tt| |This standard is proposed and administered by the Hefei General Machinery Research Institute of the Ministry of Machinery Industry. Connecting nut
Bolt hole diameter
This standard is approved by Hefei General Machinery Research Institute and Changzhou Chenghexiang Hardware Machinery Factory Responsible for drafting. The main drafters of this standard: Ren Jinlu and Gu Longfei. 1350
Thickness
Length
10| |tt||16
Degree
O-ring specifications
Inner diameter×section diameter
32. 5× 2. 65
51.5×2.65
92.5×3.55
129.4×5.7
154.3X5.7
stop valve
JB/T6918—93
The basic parameters of A2 plate level gauge are as follows Shown in Figure A2 and Table A2. Bolts
Figure A2
Table A2
JYB-120
JYB-170
JYB- 200
JYB-220
JYB-320
observable liquid level length
356| |tt||Connection size
The basic parameters of A3 threaded sight glass are shown in Figure A3 and Table A3 Ln/n|| tt||74/2
Figure A3
Bolt hole
10—9
12--11
14--11
16—| |tt||-11
Length
Dimensions
16|| tt||1349
JSL-20
JSL-27
JSL-39
JSL-45|| tt||View hole diameter
JB/T6918—93||tt| |Table A3
Straight
Diameter
M52×2
M60X2||tt ||The basic parameters of the A4 flange sight glass are shown in Figure A4 and Table A4. De
Figure A4
Table A4
View hole diameter
JSF-28| |tt||JSF-45
JSF-50
JSF-80
JSF-125
JSF-150
Additional notes: ||tt ||D.
bolt hole distribution circle
Diameter
Outer diameter
bolt hole Number
(uniformly distributed)
10||tt| |This standard is proposed and administered by the Hefei General Machinery Research Institute of the Ministry of Machinery Industry. Connecting nut
Bolt hole diameter
This standard is approved by Hefei General Machinery Research Institute and Changzhou Chenghexiang Hardware Machinery Factory Responsible for drafting. The main drafters of this standard: Ren Jinlu and Gu Longfei. 1350
Thickness
Length
10| |tt||16
Degree
O-ring specifications
Inner diameter×section diameter
32. 5× 2. 65
51.5×2.65
92.5×3.55
129.4×5.7
154.3X5.7
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Metal and glass sintering for refrigeration
Liquid level gauges and sight glasses
1 Subject content and scope of application
JB/T 6918 - 93
This standard specifies the types and basic parameters, technical requirements, test methods, Inspection rules and marking, packaging and storage. This standard is recommended for liquid level gauges and sight glasses for refrigerators and other pressure vessels with operating temperatures ranging from 40 to 180°C and design pressures not higher than 3.0MPa.
2 reference standards
Ordinary thread tolerance and fit (diameter 1~355mm) GB 1971
GB539i
Oil-resistant asbestos rubber sheet
Carbon structural steel | |tt | Blue type
QB776 glass plate and glass tube for liquid level meter
3 types and basic parameters
Liquid level meter is divided into tube type and plate type; sight glass Divided into flange type and thread type. 3.2 Model
3.2.1 Model representation method
口口口
The improved design serial number is represented by A, BC·
The liquid level gauge can observe the liquid level length or visual Hole diameter: expressed in Arabic numerals, mm type code: YG is tubular type, YB is plate level gauge, SF is flange type, SL is threaded sight glass metal and glass sintering code
3.2.2 model Example
JYG-120: Metal and glass sintered tube liquid level gauge, the observable liquid level length is 120mm. JSI.-45A: Metal and glass sintered threaded sight glass, sight hole diameter 45mm, the first improved design. 3.3 Basic parameters
Ministry of Machinery Industry of the People's Republic of China approved 1344 on 1993-07-13
Implemented on 1994-07-01
JB/T 6918—93
Liquid level The basic parameters of the meter and sight glass are shown in Appendix A (reference part) or manufactured according to the agreement between the manufacturer and the user. 4 Technical Requirements
4.1 Liquid level gauges and sight glasses shall comply with the provisions of this standard and be manufactured according to drawings and technical documents approved by prescribed procedures (or according to an agreement). 4.2 The glass of the liquid level gauge and sight glass should comply with the requirements of QB776. 4.3 The mechanical properties of the metal material sintered with the lens should not be lower than the requirements of Q235A carbon steel in GB700. 4.4 Surface roughness and dimensional tolerance
The surface roughness and dimensional tolerance are specified as follows: a. Surface roughness R of the sealing surface of the liquid level gauge and sight glass. is 3.2μm; the accuracy level of the connecting thread should comply with the 6H or 6h level specified in GB197. b.
4.5 Appearance requirements for liquid level gauges and sight glass lenses
The appearance requirements for liquid level gauges and sight glass lenses are as follows: The lenses should be transparent and colorless, or slightly light yellow: a.|| tt||There should be no obvious filamentous and comb-like stripes on the lens; b..
There should be no opaque impurities on the lens;
There should be no cracks and obvious scratches on the lens; d.
There should be no bubbles in the center of the lens and no bubbles on the edges ( There should be no dense air bubbles or scattered air bubbles exceeding the specified size (within 2mm from the joint surface). e.
The maximum size of dense bubbles should not be larger than 0.5mm, and the area should not be larger than 3mm2; there should be no more than 3 dispersed bubbles of 0.5~1.5mm in an area of ??40mm2.
4.6 Pressure test
4.6.1 Hydraulic test
Carry out the test according to the method specified in 5.2.1. There should be no cracks or leaks between the lens and the joint surface. 4.6.2 Air pressure test
The test piece can also use the method specified in Article 5.2.2 instead of the test in Article 4.6.1. There should be no cracks or leaks between the lens and the joint surface. 4.6.3 Design strength hydraulic verification test
Carry out the test according to the method specified in Article 5.2.3. The lens should not be broken, and there should be no cracks or leaks between the lens and the joint surface. 4.7 Air tightness test
Carry out the test according to the method specified in Article 5.3. There should be no cracks or leaks. 4.8 Thermal Stability Test
Carry out the test according to the method specified in Article 5.4. The lens should not be broken, and there should be no cracks between the lens and the joint surface. 4.9 Other requirements
4.9.1 The stop valve used for tubular liquid level gauges should comply with the relevant refrigeration valve requirements, and the liquid valve should be equipped with a safety protection steel ball. 4.9.2 When the tubular liquid level meter is connected with a flange, the flange size shall be manufactured according to the user's requirements or the regulations of GB9112. 4.9.3 The gasket material should comply with the regulations of GB539. 4.9.40 type rubber ring should have good compatibility with refrigerant, refrigeration oil, etc., and the size and technical requirements should comply with the regulations of GB3452.1. 5 Test methods
5.1 Appearance inspection
The appearance of the lens shall be inspected visually with a 5x magnifying glass and shall comply with the provisions of Article 4.5. 5.2 Pressure test
5.2.1 Hydraulic test
Install the liquid level gauge or sight glass on a special test device. The test medium is clean water or lubricating oil. The accuracy of the pressure gauge should not be less than 1.5 level, and use two calibrated pressure gauges with the same range (the range is preferably about 2 times the test pressure) and within the validity period. During the test, the pressure is slowly raised to 1.5 times the design pressure at a speed of no more than 0.1MPa per second, and the pressure is maintained for 3 minutes. It should comply with the provisions of Article 4.6.1. 1345
5.2.2 Air pressure test
JB/T 6918—93
Install the liquid level gauge or sight glass on a special test device. The test medium is clean air or nitrogen. The pressure The table requirements are the same as those specified in Article 5.2.1, and safety protection measures should be taken during the test. During the test, slowly increase the pressure to 1.25 times the design pressure at a speed of no more than 1.0MPa per minute, maintain the pressure for 1 minute, then reduce the pressure to the design pressure, and then use the foaming liquid or immersion method to check. It should comply with Article 4.6.2 Regulation. 5.2.3 Design strength hydraulic verification test
Slowly pressurize the test piece to the design pressure according to the method specified in Article 5.2.1, and then release the pressure to zero; then slowly pressurize it to 2.0 times the design pressure. Then release the pressure to zero, and finally slowly increase the pressure to 3.0 times the design pressure, and keep the pressure for 5 minutes. After checking and confirming that it meets the requirements of Article 4.6.3, conduct an air tightness test according to Article 5.3. It should comply with the provisions of Article 4.7. . 5.3 Air tightness test
Slowly pressurize the test piece to the design pressure according to the method specified in Article 5.2.2, keep the pressure for 1 minute, and check with foaming liquid or immersion method. It should comply with Article 4.7 Regulation. If it passes the inspection according to Article 4.6.2, this test does not need to be done. 5.4 Thermal stability test
Place the liquid level gauge or sight glass in an electric furnace, keep it at a temperature of no less than 180°C for 15 minutes, take it out, and immediately put it into a 40°C dry ice bath container. Repeat the test 5 times. , each time interval shall not be less than 30 minutes and shall comply with the provisions of Article 4.8. The air tightness test shall be carried out according to the provisions of Article 5.3 and shall comply with the provisions of Article 4.7. 6 Inspection Rules
General Requirements
Products must be inspected by the quality inspection department of the manufacturer in accordance with this standard and corresponding standards and technical documents before leaving the factory. 6.2 Factory inspection
After passing the inspection according to Articles 4.4 and 4.5, the items shall pass the inspection one by one according to Articles 4.6.1 and 4.7 or Article 4.6.2. 6.3 Type inspection
6.3.1 Type inspection shall be carried out when one of the following situations occurs: a.
Trial products of each model:
b. When there are major changes in the product design, process, and materials of each model; c. After half a year of continuous production.
6.3.2 Batch
Liquid level gauges or sight glasses of the same material and type manufactured in the same furnace in the same shift are considered to be one batch. 6.3.3 Sampling method
Randomly sample 10 pieces from each batch of products.
6.3.4 First, the inspection should be qualified according to Articles 4.4, 4.5 and 4.7, and then 4 pieces will be selected from the 10 pieces and divided into two groups, which shall be inspected according to Articles 4.6.3 and 4.8 respectively.
6.3.5 All products inspected should be qualified. If there are unqualified products, they will be dealt with according to the provisions of the following table. Inspection content
Article 4.6.3
4.8 pieces
Inspection results
1 unqualified
2 unqualified
1 unqualified each
1 Pieces unqualified
2 pieces unqualified
Duplex
Double
Double
Inspection
Times|| tt||Re-inspection results
All qualified
1 unqualified
All qualified
1 unqualified
Conclusion
Qualified
Discarded
Qualified
Discarded
Marking, packaging, transportation and storage
Liquid The position meter and sight glass should have the following marks:
Model number:
Manufacturer name and trademark;| |tt||Specifications;
Design pressure;
Manufacturing year, month or batch number.
JB/T 6918-93
2 The liquid level gauge and sight glass should be packed in cartons stuffed with paper flowers or plastic materials, and the lenses should be protected by cardboard or film. There should be product 7.2
certificate and product instructions in the packaging box.
The liquid level gauge and sight glass should be installed and handled with care to prevent heavy pressure and collision, and should be stored in a dry place free of acid and alkali corrosion. 7.3
JB/T 6918 -- 93
Appendix A
Basic parameters of liquid level gauge and sight glass
(reference part)|| The basic parameters of tt||A1 tube level gauge are shown in Figure A1 and Table A1. 1
Hedpoel
Figure A1
Table A1
Tank installation
Liquid level counting|| tt||&
TYG-120
TYG-220
TYG -320
TYG-620
TYG-920
TYG-1 220
TYG-1520
height
1||tt ||300
observable liquid level|| tt||Length
1220||tt| |1520
Outer diameter
Inner diameter
Thickness
Connecting nut
Connection size
Outer diameter × wall thickness
Globe valve|| tt||DN
JB/T6918-93
The basic parameters of A2 plate level gauge are shown in Figure A2 and Table A2. Bolts
Figure A2
Table A2
JYB-120
JYB-170
JYB- 200
JYB-220
JYB-320
observable liquid level length
356| |tt||Connection size
The basic parameters of A3 threaded sight glass are shown in Figure A3 and Table A3 Ln/n|| tt||74/2
Figure A3
Bolt hole
10—9
12--11
14--11
16—| |tt||-11
Length
Dimensions
16|| tt||1349
JSL-20
JSL-27
JSL-39
JSL-45|| tt||View hole diameter
JB/T6918—93||tt| |Table A3
Straight
Diameter
M52×2
M60X2||tt ||The basic parameters of the A4 flange sight glass are shown in Figure A4 and Table A4. De
Figure A4
Table A4
View hole diameter
JSF-28| |tt||JSF-45
JSF-50
JSF-80
JSF-125
JSF-150
Additional notes: ||tt ||D.
bolt hole distribution circle
Diameter
Outer diameter
bolt hole Number
(uniformly distributed)
10||tt| |This standard is proposed and administered by the Hefei General Machinery Research Institute of the Ministry of Machinery Industry. Connecting nut
Bolt hole diameter
This standard is approved by Hefei General Machinery Research Institute and Changzhou Chenghexiang Hardware Machinery Factory Responsible for drafting. The main drafters of this standard: Ren Jinlu and Gu Longfei. 1350
Thickness
Length
10| |tt||16
Degree
O-ring specifications
Inner diameter×section diameter
32. 5× 2. 65
51.5×2.65
92.5×3.55
129.4×5.7
154.3X5.7
Manufacturing year, month or batch number.
JB/T 6918-93
2 The liquid level gauge and sight glass should be packed in cartons stuffed with paper flowers or plastic materials, and the lenses should be protected by cardboard or film. There should be product 7.2
certificate and product instructions in the packaging box.
The liquid level gauge and sight glass should be installed and handled with care to prevent heavy pressure and collision, and should be stored in a dry place free of acid and alkali corrosion. 7.3
JB/T 6918 -- 93
Appendix A
Basic parameters of liquid level gauge and sight glass
(reference part)|| The basic parameters of tt||A1 tube level gauge are shown in Figure A1 and Table A1. 1
Hedpoel
Figure A1
Table A1
Tank installation
Liquid level counting|| tt||&
TYG-120
TYG-220
TYG -320
TYG-620
TYG-920
TYG-1 220
TYG-1520
height
1||tt ||300
observable liquid level|| tt||Length
1220||tt| |1520
Outer diameter
Inner diameter
Thickness
Connecting nut
Connection size
Outer diameter × wall thickness
Globe valve|| tt||DN
JB/T6918-93
The basic parameters of A2 plate level gauge are shown in Figure A2 and Table A2. Bolts
Figure A2
Table A2
JYB-120bZxz.net
JYB-170
JYB- 200
JYB-220
JYB-320
observable liquid level length
356| |tt||Connection size
The basic parameters of A3 threaded sight glass are shown in Figure A3 and Table A3 Ln/n|| tt||74/2
Figure A3
Bolt hole
10—9
12--11
14--11
16—| |tt||-11
Length
Dimensions
16|| tt||1349
JSL-20
JSL-27
JSL-39
JSL-45|| tt||View hole diameter
JB/T6918—93||tt| |Table A3
Straight
Diameter
M52×2
M60X2||tt ||The basic parameters of the A4 flange sight glass are shown in Figure A4 and Table A4. De
Figure A4
Table A4
View hole diameter
JSF-28| |tt||JSF-45
JSF-50
JSF-80
JSF-125
JSF-150
Additional notes: ||tt ||D.
bolt hole distribution circle
Diameter
Outer diameter
bolt hole Number
(uniformly distributed)
10||tt| |This standard is proposed and administered by the Hefei General Machinery Research Institute of the Ministry of Machinery Industry. Connecting nut
Bolt hole diameter
This standard is approved by Hefei General Machinery Research Institute and Changzhou Chenghexiang Hardware Machinery Factory Responsible for drafting. The main drafters of this standard: Ren Jinlu and Gu Longfei. 1350
Thickness
Length
10| |tt||16
Degree
O-ring specifications
Inner diameter×section diameter
32. 5× 2. 65
51.5×2.65
92.5×3.55
129.4×5.7
154.3X5.7
Manufacturing year, month or batch number.
JB/T 6918-93
2 The liquid level gauge and sight glass should be packed in cartons filled with paper flowers or plastic materials, and the lenses should be protected by cardboard or film. There should be product 7.2
certificate and product instructions in the packaging box.
The liquid level gauge and sight glass should be installed and handled with care to prevent heavy pressure and collision, and should be stored in a dry place free of acid and alkali corrosion. 7.3
JB/T 6918 -- 93
Appendix A
Basic parameters of liquid level gauge and sight glass
(reference part)|| The basic parameters of tt||A1 tube level gauge are shown in Figure A1 and Table A1. 1
Hedpoel
Figure A1
Table A1
Tank installation
Liquid level counting|| tt||&
TYG-120
TYG-220
TYG -320
TYG-620
TYG-920
TYG-1 220
TYG-1520
height
1||tt ||300
observable liquid level|| tt||Length
1220||tt| |1520
Outer diameter
Inner diameter
Thickness
Connecting nut
Connection size
Outer diameter × wall thickness
Globe valve|| tt||DN
JB/T6918-93
The basic parameters of A2 plate level gauge are shown in Figure A2 and Table A2. Bolts
Figure A2
Table A2
JYB-120
JYB-170
JYB- 200
JYB-220
JYB-320
observable liquid level length
356| |tt||Connection size
The basic parameters of A3 threaded sight glass are shown in Figure A3 and Table A3 Ln/n|| tt||74/2
Figure A3
Bolt hole
10—9
12--11
14--11
16—| |tt||-11
Length
Dimensions
16|| tt||1349
JSL-20
JSL-27
JSL-39
JSL-45|| tt||View hole diameter
JB/T6918—93||tt| |Table A3
Straight
Diameter
M52×2
M60X2||tt ||The basic parameters of the A4 flange sight glass are shown in Figure A4 and Table A4. De
Figure A4
Table A4
View hole diameter
JSF-28| |tt||JSF-45
JSF-50
JSF-80
JSF-125
JSF-150
Additional notes: ||tt ||D.
bolt hole distribution circle
Diameter
Outer diameter
bolt hole Number
(uniformly distributed)
10||tt| |This standard is proposed and administered by the Hefei General Machinery Research Institute of the Ministry of Machinery Industry. Connecting nut
Bolt hole diameter
This standard is approved by Hefei General Machinery Research Institute and Changzhou Chenghexiang Hardware Machinery Factory Responsible for drafting. The main drafters of this standard: Ren Jinlu and Gu Longfei. 1350
Thickness
Length
10| |tt||16
Degree
O-ring specifications
Inner diameter×section diameter
32. 5× 2. 65
51.5×2.65
92.5×3.55
129.4×5.7
154.3X5.7
JB/T 6918 -- 93
Appendix A
Basic parameters of liquid level gauge and sight glass
(reference part)|| The basic parameters of tt||A1 tube level gauge are shown in Figure A1 and Table A1. 1
Hedpoel
Figure A1
Table A1
Tank installation
Liquid level counting|| tt||&
TYG-120
TYG-220
TYG -320
TYG-620
TYG-920
TYG-1 220
TYG-1520
height
1||tt ||300
observable liquid level|| tt||Length
1220||tt| |1520
Outer diameter
Inner diameter
Thickness
Connecting nut
Connection size
Outer diameter × wall thickness
Globe valve|| tt||DN
JB/T6918-93
The basic parameters of A2 plate level gauge are shown in Figure A2 and Table A2. Bolts
Figure A2
Table A2
JYB-120
JYB-170
JYB- 200
JYB-220
JYB-320
observable liquid level length
356| |tt||Connection size
The basic parameters of A3 threaded sight glass are shown in Figure A3 and Table A3 Ln/n|| tt||74/2
Figure A3
Bolt hole
10—9
12--11
14--11
16—| |tt||-11
Length
Dimensions
16|| tt||1349
JSL-20
JSL-27
JSL-39
JSL-45|| tt||View hole diameter
JB/T6918—93||tt| |Table A3
Straight
Diameter
M52×2
M60X2||tt ||The basic parameters of the A4 flange sight glass are shown in Figure A4 and Table A4. De
Figure A4
Table A4
View hole diameter
JSF-28| |tt||JSF-45
JSF-50
JSF-80
JSF-125
JSF-150
Additional notes: ||tt ||D.
bolt hole distribution circle
Diameter
Outer diameter
bolt hole Number
(uniformly distributed)
10||tt| |This standard is proposed and administered by the Hefei General Machinery Research Institute of the Ministry of Machinery Industry. Connecting nut
Bolt hole diameter
This standard is approved by Hefei General Machinery Research Institute and Changzhou Chenghexiang Hardware Machinery Factory Responsible for drafting. The main drafters of this standard: Ren Jinlu and Gu Longfei. 1350
Thickness
Length
10| |tt||16
Degree
O-ring specifications
Inner diameter×section diameter
32. 5× 2. 65
51.5×2.65
92.5×3.55
129.4×5.7
154.3X5.7
JB/T 6918 -- 93
Appendix A
Basic parameters of liquid level gauge and sight glass
(reference part)|| The basic parameters of tt||A1 tube level gauge are shown in Figure A1 and Table A1. 1
Hedpoel
Figure A1
Table A1
Tank installation
Liquid level counting|| tt||&
TYG-120
TYG-220
TYG -320
TYG-620
TYG-920
TYG-1 220
TYG-1520
height
1||tt ||300
observable liquid level|| tt||Length
1220||tt| |1520
Outer diameter
Inner diameter
Thickness
Connecting nut
Connection size
Outer diameter × wall thickness
Globe valve|| tt||DN
JB/T6918-93
The basic parameters of A2 plate level gauge are shown in Figure A2 and Table A2. Bolts
Figure A2
Table A2
JYB-120
JYB-170
JYB- 200
JYB-220
JYB-320
observable liquid level length
356| |tt||Connection size
The basic parameters of A3 threaded sight glass are shown in Figure A3 and Table A3 Ln/n|| tt||74/2
Figure A3
Bolt hole
10—9
12--11
14--11
16—| |tt||-11
Length
Dimensions
16|| tt||1349
JSL-20
JSL-27
JSL-39
JSL-45|| tt||View hole diameter
JB/T6918—93||tt| |Table A3
Straight
Diameter
M52×2
M60X2||tt ||The basic parameters of the A4 flange sight glass are shown in Figure A4 and Table A4. De
Figure A4
Table A4
View hole diameter
JSF-28| |tt||JSF-45
JSF-50
JSF-80
JSF-125
JSF-150
Additional notes: ||tt ||D.
bolt hole distribution circle
Diameter
Outer diameter
bolt hole Number
(uniformly distributed)
10||tt| |This standard is proposed and administered by the Hefei General Machinery Research Institute of the Ministry of Machinery Industry. Connecting nut
Bolt hole diameter
This standard is approved by Hefei General Machinery Research Institute and Changzhou Chenghexiang Hardware Machinery Factory Responsible for drafting. The main drafters of this standard: Ren Jinlu and Gu Longfei. 1350
Thickness
Length
10| |tt||16
Degree
O-ring specifications
Inner diameter×section diameter
32. 5× 2. 65
51.5×2.65
92.5×3.55
129.4×5.7
154.3X5.7
stop valve
JB/T6918—93
The basic parameters of A2 plate level gauge are as follows Shown in Figure A2 and Table A2. Bolts
Figure A2
Table A2
JYB-120
JYB-170
JYB- 200
JYB-220
JYB-320
observable liquid level length
356| |tt||Connection size
The basic parameters of A3 threaded sight glass are shown in Figure A3 and Table A3 Ln/n|| tt||74/2
Figure A3
Bolt hole
10—9
12--11
14--11
16—| |tt||-11
Length
Dimensions
16|| tt||1349
JSL-20
JSL-27
JSL-39
JSL-45|| tt||View hole diameter
JB/T6918—93||tt| |Table A3
Straight
Diameter
M52×2
M60X2||tt ||The basic parameters of the A4 flange sight glass are shown in Figure A4 and Table A4. De
Figure A4
Table A4
View hole diameter
JSF-28| |tt||JSF-45
JSF-50
JSF-80
JSF-125
JSF-150
Additional notes: ||tt ||D.
bolt hole distribution circle
Diameter
Outer diameter
bolt hole Number
(uniformly distributed)
10||tt| |This standard is proposed and administered by the Hefei General Machinery Research Institute of the Ministry of Machinery Industry. Connecting nut
Bolt hole diameter
This standard is approved by Hefei General Machinery Research Institute and Changzhou Chenghexiang Hardware Machinery Factory Responsible for drafting. The main drafters of this standard: Ren Jinlu and Gu Longfei. 1350
Thickness
Length
10| |tt||16
Degree
O-ring specifications
Inner diameter×section diameter
32. 5× 2. 65
51.5×2.65
92.5×3.55
129.4×5.7
154.3X5.7
stop valve
JB/T6918—93
The basic parameters of A2 plate level gauge are as follows Shown in Figure A2 and Table A2. Bolts
Figure A2
Table A2
JYB-120
JYB-170
JYB- 200
JYB-220
JYB-320
observable liquid level length
356| |tt||Connection size
The basic parameters of A3 threaded sight glass are shown in Figure A3 and Table A3 Ln/n|| tt||74/2
Figure A3
Bolt hole
10—9
12--11
14--11
16—| |tt||-11
Length
Dimensions
16|| tt||1349
JSL-20
JSL-27
JSL-39
JSL-45|| tt||View hole diameter
JB/T6918—93||tt| |Table A3
Straight
Diameter
M52×2
M60X2||tt ||The basic parameters of the A4 flange sight glass are shown in Figure A4 and Table A4. De
Figure A4
Table A4
View hole diameter
JSF-28| |tt||JSF-45
JSF-50
JSF-80
JSF-125
JSF-150
Additional notes: ||tt ||D.
bolt hole distribution circle
Diameter
Outer diameter
bolt hole Number
(uniformly distributed)
10||tt| |This standard is proposed and administered by the Hefei General Machinery Research Institute of the Ministry of Machinery Industry. Connecting nut
Bolt hole diameter
This standard is approved by Hefei General Machinery Research Institute and Changzhou Chenghexiang Hardware Machinery Factory Responsible for drafting. The main drafters of this standard: Ren Jinlu and Gu Longfei. 1350
Thickness
Length
10| |tt||16
Degree
O-ring specifications
Inner diameter×section diameter
32. 5× 2. 65
51.5×2.65
92.5×3.55
129.4×5.7
154.3X5.7
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