Some standard content:
Shipbuilding Industry Standard of the People's Republic of China
CB/T3686-1995
Electric Steam Water Heater
Published on 1995-06-19
Published by China State Shipbuilding Corporation
Implemented on 1996-04-01
Shipbuilding Industry Standard of the People's Republic of China
Electric Steam Water Heater
Subject Content and Scope of Application
CB/T3686-1995
Classification Number: U41
This standard specifies the classification, technical requirements, test methods, inspection rules, packaging and transportation requirements of electric steam heating water heaters and electric heating water heaters (hereinafter referred to as water heaters). This standard applies to water heaters used in fresh water pipe systems for domestic use on ships and offshore facilities. 2 Reference standards
GB573 Marine lap-welded steel flanges
GB712 Structural steel for hulls
GB1527 Drawn copper tubes
GB2506 Marine lap-welded steel flanges (four-position) GB3323 Radiography and quality classification of steel fusion-welded butt joints GB/T4237 Hot-rolled stainless steel plates
GB9719 General technical requirements for marine electric heating appliances GB11037 Hydraulic test for marine auxiliary boilers and pressure vessels Test method ZBU41005 Inspection of raw materials for ship auxiliary boilers CB*3250 General technical conditions for electrical control equipment of ship auxiliary machinery "Rules for Classification and Construction of Steel Seagoing Vessels" China Classification Society, 1989 3 Product classification
The series parameters and structural forms of electric steam heating hot water cabinets are shown in Table 1 and Figure 1. 3.1
China State Shipbuilding Corporation 1995-06-19 Approved Steam
Steam heating
Hot water
Consumption Volume
Hot water egg
Electric heating
440V.60Hz
380V, 50Hz
1996-04-01 implementation
National water import
0.12m0.2ml, e.3m
CB/T3686-1995
Cold water import
Waterproof import:
1-pressure gauge; 2-overflow controller; 3-body: 4 Humidity meter; 5-Safety valve 6-Control box, ?-Electric heater: 8-Steam heater: 9-Bleeding agent Figure 1
3.2 The series parameters and structural forms of the electric heating hot water cabinet are shown in Table 2 and Figure 2, Table 2
Design pressure
Working force
Water inlet fullness
Water outlet temperature
Heating water volume
Electric heating power
Hot water outlet
Precipitation inlet
440 V, 60 Hzi
380V.50Hz
Return water inlet
6.12m;0.2m, 0.3m
CB/T3686—1995
Cold water inlet
National water inlet
1-pressure gauge; 2-temperature controller; 3-body; 4-humidity gauge; 5-safety valve: 6-dig box; 7-electric heater: 8-discharge 3.3 The basic dimensions of the electric steam heating hot water cabinet are in accordance with Table 3. Volume
Steam heating area
The basic dimensions of the electric heating hot water cabinet are in Table 4.
2032DN40DN32DN25
Water outlet!
3.5 Marking examples
CB/T3686—1995
Hot water tank with electric steam heating of 0.5m3: Hot water tank 0.5CB/T3686—1995
Hot water tank with electric heating of 0.5m3:
Hot water tank D0.5CB/T3686-1995
4 Technical requirements
4.1 Design requirements
4.1.1 A complete set of hot water tanks shall include safety valves, temperature controllers, pressure gauges, thermometers, relief valves, electric heaters and control boxes. These accessories shall meet the requirements for marine use.
4.1.2 The opening pressure of the safety valve shall be greater than the working pressure and less than the design pressure. 4.1.3 The working pressure shall be indicated by a red line on the pressure gauge dial. The accuracy of the pressure gauge is 1.5 level, and its range is preferably 1.5 to 2 times of the working pressure.
4.1.4 The inlet and outlet connection flanges of the hot water cabinet shall comply with the requirements of GB573 or GB2506. 4.1.5 The body of the hot water cabinet shall be able to withstand the strength test of 1.5 times the design pressure without damage or obvious deformation. The complete set of hot water cabinets shall be tested for tightness at 1.25 times the design pressure and shall not leak. 4.1.6 The steam heating pipe shall be able to withstand the strength test at 1.5 times the steam pressure without damage or obvious deformation. The complete set of steam heaters shall be tested for tightness at 1.25 times the steam pressure and shall not leak. 4.1.7 The electric and steam heating of the electric steam heating hot water cabinet can be used simultaneously or separately. 4.2 Manufacturing requirements
4.2.1 The head and the cylinder shall be formed by mechanical cold working or hot working, and hammer forming shall not be used. When the head is formed by hot pressing, overheating shall not occur.
4.2.2 The roundness of the shell of the hot water tank refers to the difference between the maximum inner diameter and the minimum inner diameter measured on the same section, which should not be greater than 1% of the designed inner diameter of the section.
4.2.3 The minimum wall thickness of the hot water tank head after forming shall not be less than 90% of the designed thickness. 4.2.4 When rolling the shell, defects such as edge beveling, overbending, shape, and drumming should be prevented. The straightness of the hot water tank cylinder after assembly should not exceed 2.5mm per meter length.
4.3 Welding requirements Www.bzxZ.net
4.3.1 The welding of the hot water tank must be undertaken by a welder who has passed the "Welder Examination Rules" issued by the Ship Inspection Bureau, and the welder's code should be stamped near the weld.
4.3.2 Before welding, the oxides, moisture, oil stains and other dirt that affect the welding quality within the 25mm area of the weldment groove should be removed. 4.3.3 Welding materials should be low-hydrogen type and should be inspected before entering the factory according to the requirements of ZBU41005. 4.3.4 When any of the following conditions occur in the welding environment, welding shall not be carried out without effective measures. 4
Wind speed is greater than or equal to 10m/s;
Relative humidity is greater than 90%;
c. Raining;
d. Snowing.
CB/T3686-1995
4.3.5 When the temperature of the weldment is lower than 0℃, it should be preheated to about 15℃ within 100mm of the welding location. 4.4 Requirements for welds
4.4.1 The weld surface should be uniform and dense, without cracks, weld bumps, slag inclusions, arc pits and unfilled depressions. If the above defects exist but are not serious, repairs are allowed.
4.4.2 The weld and the parent material should have a smooth transition. 4.4.3 The undercut depth of the weld surface should not be greater than 0.5mm, the continuous length of the undercut should not be greater than 100mm, and the length of the undercut on both sides of the weld should not exceed 10% of the length of the weld.
4.4.4 The slag on the weld and the spatter on both sides must be removed. 4.4.5 The thickness of the weld defect or mechanical damage after grinding and repair should not be less than the negative deviation of the nominal thickness of the parent material minus the thickness of the steel plate. 4.4.6 Cross welds are not allowed in the assembly welding of hot water tanks. The distance between the longitudinal welds between the head and the cylinder section and between the two sections shall not be less than 100mm.
4.4.7 The welding process of the first hot water tank shall be approved, and the weld shall be inspected by X-ray. For hot water tanks produced in batches, when the quality can be guaranteed in terms of process, X-ray spot checks can be carried out on 30 to 40 units as a batch. 4.5 Material requirements
4.5.1 The body and head of the hot water cabinet shall be made of stainless steel or killed steel. The technical requirements of stainless steel shall comply with the provisions of GB/T4237, and the technical requirements of killed steel shall comply with the provisions of Class B in GB712. 4.5.2 Copper tubes shall be used for steam heating pipes, and their technical requirements shall comply with the provisions of GB1527. 4.5.3 Materials shall be inspected and accepted in accordance with the requirements of ZBU41005 standard. 4.6 Coating and assembly requirements
4.6-1 For hot water cabinets whose bodies are made of killed steel, after passing the strength test, the inner surface shall be treated according to the coating requirements, and then coated with non-toxic coatings with a temperature resistance of not less than 80°C that have been tested and qualified. 4.6.2 After the strength test and tightness test of the hot water cabinet are passed, the outer surface of the hot water cabinet made of killed steel shall be derusted and coated with anti-rust primer and silver-gray topcoat. The outer surface of the hot water cabinet is covered with rock wool or slag wool with a thickness of 8 = 40mm, and then wrapped with a layer of galvanized thin steel plate with a thickness of 0.7mm. 4.6.3 The temperature controller of the hot water cabinet should be able to automatically adjust to ensure that the water humidity in the hot water cabinet is within the range of 60~70C. 4.7 Safety requirements
4.7.1 The protection level of the electrical control box and junction box of the hot water cabinet is IP22. 4.7.2 The metal shell of the hot water cabinet shall be provided with a grounding terminal and be marked with clear, obvious and durable signs. The grounding connection shall be reliable, and the grounding resistance between the grounding terminal and the easily accessible non-live metal parts shall not be greater than 0.1. 4.7.3 The hot water cabinet shall be provided with a water loss protection device to reliably protect the electric heating element from being burned when the water is lost. 4.7.4 In the cold and hot states, the live parts of the hot water cabinet with different polarities and between all live parts and the metal shell shall be able to withstand an AC test voltage of 2 times the rated voltage plus 1000V, but at least 1500V, with a rated frequency of 25~100Hz, for 1min without breakdown or flashover.
4.7.5 The cold insulation resistance between the live parts of the hot water cabinet with different polarities and between all live parts shall not be less than 10MQ, and the hot insulation resistance shall not be less than 1MQ.
4.8 Requirements for electric heaters
The technical requirements for electric heaters shall comply with the requirements of GB9719. 4.9 Requirements for control box
Control box shall comply with the relevant provisions of CB*3250. 5
5 Test methods
5.1 Appearance inspection
CB/T3686-1995
Inspect the appearance, material selection, accessories, dimensions, etc. of the hot water cabinet, and the results shall comply with the requirements of 4.1.1, 4.1.3, 4.2, 4.3.2, 4.3.3, 4.4.1~4.4.6, 4.5, 4.6.
5.2 Weld inspection
5.2.1 Inspection of welding test plate includes positive bending test, reverse bending test, transverse tensile test of welding head, macroscopic test, fracture structure inspection, etc. The manufacturing and testing requirements of welding specimens shall comply with the relevant contents of Part VIII and Chapter 4 of "Rules for Classification and Construction of Sea-going Steel Ships". 100% X-ray inspection shall be conducted on the welded test plate, and the film evaluation shall be in accordance with the provisions of GB3323. The weld level is qualified. 5.2.2 When unacceptable defects are found on the weld, repair is allowed after removal, and X-ray inspection shall be carried out after repair. The number of repairs on the same part shall not exceed 2 times.
5.3 Strength test and tightness test
5.3.1 After the hot water cabinet body is manufactured and passed the inspection, a strength test shall be carried out. The test method shall be carried out in accordance with GB11037, and the test results shall comply with the provisions of Article 4.1.5.
5.3.2 The hot water cabinet can only be tested for tightness after the strength test is passed and the accessories are installed. The tightness test uses clean water as the medium, and the test pressure is 1.25 times the design pressure. During the test, the test pressure is slowly increased, and the pressure is maintained for 20 minutes after reaching the specified test pressure, and then reduced to the design pressure. All welds and joints are checked for leakage, and the results shall comply with the provisions of Article 4.1.5. 5.3.3 After the steam heating pipe is bent and formed and passes the inspection, a strength test shall be carried out. The test method shall be carried out in accordance with GB11037, and the test results shall comply with the provisions of Article 4.1.6.
5.3.4 The steam heater can only be subjected to a tightness test after the steam heating pipe strength test passes and the accessories are installed. The tightness test uses clean water as the medium, and the test pressure is 1.25 times the steam pressure. During the test, the test pressure is slowly increased, and the pressure is maintained for 20 minutes after reaching the specified test pressure, and then reduced to the steam pressure. All welds and joints are checked for leakage, and the results shall comply with the provisions of Article 4.1.6. 5.4 Opening and reseating test of safety valve
After the hot water cabinet tightness test passes, the safety valve is adjusted to the specified value and a start-up test is carried out. The opening pressure should be greater than the operating pressure and less than the design pressure, and the test should be carried out three times in a row. The results shall comply with the provisions of Article 4.1.2. 5.5 Automatic temperature adjustment test
Adjust the automatic temperature regulator in the hot water cabinet to the specified range, observe the water supply temperature of the hot water cabinet, and the result should meet the requirements of Article 4.6.3.
5.6 Water loss protection test
Carry out the water loss protection device test at rated voltage, the protection device should work reliably, and the electric heating element should not be damaged. The test should be repeated 5 times.
5.7 Withstand voltage test
Carry out according to the method specified in Article 4.8.6.2 of GB9719. 5.8 Insulation resistance test
Carry out according to the method specified in Article 4.8.7.2 of GB9719. 6 Inspection rules
6.1 Factory inspection
Each hot water cabinet should be inspected at the factory, and can only be shipped after passing the inspection. 6.2 Type inspection
For any of the following situations, the hot water cabinet shall be subject to type inspection: a. New products or products produced by a new factory;
b. When there are major changes in product design, process, or materials that are sufficient to affect its main performance; 6
Batch production is conducted once every four years.
CB/T3686-1995
6.3The items for factory inspection and type inspection shall be in accordance with the provisions of Table 5. Table 5
Appearance inspection
Strength and tightness test
Weld inspection
Safety valve test
Automatic temperature control test
Water loss protection test
Cold withstand voltage test
Hot withstand voltage test
Cold insulation resistance measurement
Hot insulation resistance measurement
Marking, packaging, storage
Type inspection
Factory inspection
Inspection method
Each hot water cabinet shall be marked in a conspicuous position. A corrosion-resistant nameplate shall be fixed, and the following contents shall be marked on the nameplate: a.
Product name;
Manufacturer name;
Product mark:
Working pressure, MPa
Design pressure, MPa;
Steam pressure, MPa;
Electric heating power, kW;
Hot water temperature, C;
Weight, kg+
Volume, m;
Manufacturing number:
Manufacturing date:
Ship inspection mark.
Each hot water tank shall be accompanied by the following documents:
General plan:
Supply technical documents;
Factory inspection quality guarantee;
Ship inspection certificate.
7.3 Packaging and storage
Hot water tanks shall be stored in a dry place. 7.3.1
Technical requirements
4.1.5,4.1.6
4. 4.7
CB/T3686—1995
7.3.2 The hot water cabinet should be packed in a wooden frame structure, covered with a layer of rainproof oil paper. 7.3.3 The packing box should indicate the product name, model, weight, etc., and the hoisting position and direction should be marked. Additional remarks:
This standard was proposed by the 603 Institute of China State Shipbuilding Corporation. This standard is under the jurisdiction of the Auxiliary Boiler Sub-Technical Committee of the National Technical Committee for Standardization of Marine Machinery. This standard was drafted by the 603 Institute of China State Shipbuilding Corporation, Qingdao Yinhe Electronics Company, and Hudong Shipyard. The main drafters of this standard are Zhong Chongxin, Zhang Yezhen, and Wu Zhongqi.3 Strength test and tightness test
5.3.1 After the hot water tank body is manufactured and passed the inspection, a strength test shall be carried out. The test method shall be carried out in accordance with GB11037, and the test results shall comply with the provisions of Article 4.1.5.
5.3.2 The hot water tank can only be tested for tightness after the strength test is passed and the accessories are installed. The tightness test uses clean water as the medium, and the test pressure is 1.25 times the design pressure. During the test, the test pressure is slowly increased. After reaching the specified test pressure, the pressure is maintained for 20 minutes, and then reduced to the design pressure. All welds and joints are checked for leakage, and the results shall comply with the provisions of Article 4.1.5. 5.3.3 After the steam heating pipe is bent and formed and passed the inspection, a strength test shall be carried out. The test method shall be carried out in accordance with GB11037, and the test results shall comply with the provisions of Article 4.1.6.
5.3.4 The steam heater can only be tested for tightness after the steam heating pipe strength test is passed and the accessories are installed. The tightness test uses clean water as the medium, and the test pressure is 1.25 times the steam pressure. During the test, slowly increase the test pressure, maintain the pressure for 20 minutes after reaching the specified test pressure, and then reduce it to steam pressure. Check for leakage on all welds and joints, and the results should comply with the provisions of Article 4.1.6. 5.4 Opening and return seat test of safety valve
After the hot water cabinet tightness test is qualified, adjust the safety valve to the specified value and conduct a jump test. The opening pressure should be greater than the operating pressure and less than the design pressure, and the test should be repeated 3 times. The results should comply with the provisions of Article 4.1.2. 5.5 Automatic temperature adjustment test
Adjust the automatic temperature regulator in the hot water cabinet to the specified range, observe the water supply temperature of the hot water cabinet, and the results should comply with the requirements of Article 4.6.3.
5.6 Water loss protection test
The water loss protection device is tested at rated voltage. The protection device should work reliably and the electric heating element should not be damaged. The test should be repeated 5 times.
5.7 Withstand voltage test
Perform the method specified in Article 4.8.6.2 of GB9719. 5.8 Insulation resistance test
Perform the method specified in Article 4.8.7.2 of GB9719. 6 Inspection rules
6.1 Factory inspection
Each hot water cabinet shall undergo factory inspection and can only leave the factory after passing the inspection. 6.2 Type inspection
For any of the following situations, the hot water cabinet shall undergo type inspection: a. New products or products produced by a transferred factory;
b. When the product design, process, and materials have major changes that are sufficient to affect its main performance; 6
Batch production shall be conducted every four years.
CB/T3686-1995
6.3 The items of factory inspection and type inspection shall be in accordance with the provisions of Table 5. Table 5
Appearance inspection
Strength and tightness test
Weld inspection
Safety valve test
Automatic temperature control test
Water loss protection test
Cold withstand voltage test
Hot withstand voltage test
Cold insulation resistance measurement
Hot insulation resistance measurement
Marking, packaging, storage
Type inspection
Factory inspection
Inspection method
Each hot water cabinet shall be marked in a conspicuous position. A corrosion-resistant nameplate shall be fixed, and the following contents shall be marked on the nameplate: a.
Product name;
Manufacturer name;
Product mark:
Working pressure, MPa
Design pressure, MPa;
Steam pressure, MPa;
Electric heating power, kW;
Hot water temperature, C;
Weight, kg+
Volume, m;
Manufacturing number:
Manufacturing date:
Ship inspection mark.
Each hot water tank shall be accompanied by the following documents:
General plan:
Supply technical documents;
Factory inspection quality guarantee;
Ship inspection certificate.
7.3 Packaging and storage
Hot water tanks shall be stored in a dry place. 7.3.1
Technical requirements
4.1.5,4.1.6
4. 4.7
CB/T3686—1995
7.3.2 The hot water cabinet should be packed in a wooden frame structure, covered with a layer of rainproof oil paper. 7.3.3 The packing box should indicate the product name, model, weight, etc., and the hoisting position and direction should be marked. Additional remarks:
This standard was proposed by the 603 Institute of China State Shipbuilding Corporation. This standard is under the jurisdiction of the Auxiliary Boiler Sub-Technical Committee of the National Technical Committee for Standardization of Marine Machinery. This standard was drafted by the 603 Institute of China State Shipbuilding Corporation, Qingdao Yinhe Electronics Company, and Hudong Shipyard. The main drafters of this standard are Zhong Chongxin, Zhang Yezhen, and Wu Zhongqi.3 Strength test and tightness test
5.3.1 After the hot water tank body is manufactured and passed the inspection, a strength test shall be carried out. The test method shall be carried out in accordance with GB11037, and the test results shall comply with the provisions of Article 4.1.5.
5.3.2 The hot water tank can only be tested for tightness after the strength test is passed and the accessories are installed. The tightness test uses clean water as the medium, and the test pressure is 1.25 times the design pressure. During the test, the test pressure is slowly increased. After reaching the specified test pressure, the pressure is maintained for 20 minutes, and then reduced to the design pressure. All welds and joints are checked for leakage, and the results shall comply with the provisions of Article 4.1.5. 5.3.3 After the steam heating pipe is bent and formed and passed the inspection, a strength test shall be carried out. The test method shall be carried out in accordance with GB11037, and the test results shall comply with the provisions of Article 4.1.6.
5.3.4 The steam heater can only be tested for tightness after the steam heating pipe strength test is passed and the accessories are installed. The tightness test uses clean water as the medium, and the test pressure is 1.25 times the steam pressure. During the test, slowly increase the test pressure, maintain the pressure for 20 minutes after reaching the specified test pressure, and then reduce it to steam pressure. Check for leakage on all welds and joints, and the results should comply with the provisions of Article 4.1.6. 5.4 Opening and return seat test of safety valve
After the hot water cabinet tightness test is qualified, adjust the safety valve to the specified value and conduct a jump test. The opening pressure should be greater than the operating pressure and less than the design pressure, and the test should be repeated 3 times. The results should comply with the provisions of Article 4.1.2. 5.5 Automatic temperature adjustment test
Adjust the automatic temperature regulator in the hot water cabinet to the specified range, observe the water supply temperature of the hot water cabinet, and the results should comply with the requirements of Article 4.6.3.
5.6 Water loss protection test
The water loss protection device is tested at rated voltage. The protection device should work reliably and the electric heating element should not be damaged. The test should be repeated 5 times.
5.7 Withstand voltage test
Perform the method specified in Article 4.8.6.2 of GB9719. 5.8 Insulation resistance test
Perform the method specified in Article 4.8.7.2 of GB9719. 6 Inspection rules
6.1 Factory inspection
Each hot water cabinet shall undergo factory inspection and can only leave the factory after passing the inspection. 6.2 Type inspection
For any of the following situations, the hot water cabinet shall undergo type inspection: a. New products or products produced by a transferred factory;
b. When the product design, process, and materials have major changes that are sufficient to affect its main performance; 6
Batch production shall be conducted every four years.
CB/T3686-1995
6.3 The items of factory inspection and type inspection shall be in accordance with the provisions of Table 5. Table 5
Appearance inspection
Strength and tightness test
Weld inspection
Safety valve test
Automatic temperature control test
Water loss protection test
Cold withstand voltage test
Hot withstand voltage test
Cold insulation resistance measurement
Hot insulation resistance measurement
Marking, packaging, storage
Type inspection
Factory inspection
Inspection method
Each hot water cabinet shall be marked in a conspicuous position. A corrosion-resistant nameplate shall be fixed, and the following contents shall be marked on the nameplate: a.
Product name;
Manufacturer name;
Product mark:
Working pressure, MPa
Design pressure, MPa;
Steam pressure, MPa;
Electric heating power, kW;
Hot water temperature, C;
Weight, kg+
Volume, m;
Manufacturing number:
Manufacturing date:
Ship inspection mark.
Each hot water tank shall be accompanied by the following documents:
General plan:
Supply technical documents;
Factory inspection quality guarantee;
Ship inspection certificate.
7.3 Packaging and storage
Hot water tanks shall be stored in a dry place. 7.3.1
Technical requirements
4.1.5,4.1.6
4. 4.7
CB/T3686—1995
7.3.2 The hot water cabinet should be packed in a wooden frame structure, covered with a layer of rainproof oil paper. 7.3.3 The packing box should indicate the product name, model, weight, etc., and the hoisting position and direction should be marked. Additional remarks:
This standard was proposed by the 603 Institute of China State Shipbuilding Corporation. This standard is under the jurisdiction of the Auxiliary Boiler Sub-Technical Committee of the National Technical Committee for Standardization of Marine Machinery. This standard was drafted by the 603 Institute of China State Shipbuilding Corporation, Qingdao Yinhe Electronics Company, and Hudong Shipyard. The main drafters of this standard are Zhong Chongxin, Zhang Yezhen, and Wu Zhongqi.3 Packaging and storage
The hot water cabinet should be stored in a dry place. 7.3.1
Technical requirements
4.1.5, 4.1.6
4. 4.7
CB/T3686—1995
7.3.2 The hot water cabinet should be packed in a wooden frame structure, covered with a layer of rainproof oil paper. 7.3.3 The packing box should indicate the product name, model, weight, etc., and the lifting position and direction should be marked. Additional notes:
This standard was proposed by the 603 Institute of China State Shipbuilding Corporation. This standard is under the jurisdiction of the Auxiliary Boiler Sub-Technical Committee of the National Technical Committee for Standardization of Marine Machinery. This standard was drafted by the 603 Institute of China State Shipbuilding Corporation, Qingdao Yinhe Electronics Company, and Hudong Shipyard. The main drafters of this standard are Zhong Chongxin, Zhang Yezhen, and Wu Zhongqi.3 Packaging and storage
The hot water cabinet should be stored in a dry place. 7.3.1
Technical requirements
4.1.5, 4.1.6
4. 4.7
CB/T3686—1995
7.3.2 The hot water cabinet should be packed in a wooden frame structure, covered with a layer of rainproof oil paper. 7.3.3 The packing box should indicate the product name, model, weight, etc., and the lifting position and direction should be marked. Additional notes:
This standard was proposed by the 603 Institute of China State Shipbuilding Corporation. This standard is under the jurisdiction of the Auxiliary Boiler Sub-Technical Committee of the National Technical Committee for Standardization of Marine Machinery. This standard was drafted by the 603 Institute of China State Shipbuilding Corporation, Qingdao Yinhe Electronics Company, and Hudong Shipyard. The main drafters of this standard are Zhong Chongxin, Zhang Yezhen, and Wu Zhongqi.
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