JB/T 7985-2002 Small boilers and atmospheric pressure hot water boiler technology
Some standard content:
ICS27.060
Machinery Industry Standard of the People's Republic of China
JB/T7985—2002
Replaces JB/T7985—1995
Specification for small type boilers and atmospheric hot water boilers2002-12-27 Issued
2003-04-01 Implementation
The State Economic and Trade Commission of the People's Republic of China Issued Foreword
Normative references
Terms and definitions
Parameter series
Model synthesis method
Technical requirements
Performance under rated conditions
Basic requirements for design
Requirements for auxiliary equipment and accessories for boilers
Functional requirements for detection and monitoring instruments and devices Inspection and testing
Material inspection
Quality inspection of major components and assembly
Welding quality inspection
Hydraulic pressure test
Thermal performance.
Emission of air pollutants
Inspection and test rules
Paint, packaging, marking and random documents.
Installation and use requirements
Atmospheric pressure hot water boiler system,
Quality responsibility
Thermal efficiency of layered combustion boiler,
Thermal efficiency of oil and gas boilers
The difference between the maximum and minimum diameters of the same section of the boiler shell and furnace, and the angle Table 3
Table 4 Factory inspection and type test items and requirements JB/T79852002
JB/T79852002
This standard replaces JB/T7985-1995 "General Technical Conditions for Atmospheric Pressure Hot Water Boilers". Compared with JB/T7985-1995, the main changes of this standard are as follows: the name of the standard is changed to "Technical conditions for small boilers and atmospheric hot water boilers": the definition of small boilers is added (3.1 of this edition); the parameter series of atmospheric hot water boilers is adjusted (Table 1 of the 1995 edition: 4.2 of this edition); the method of compiling product models of small boilers is added (5.1 of this edition); the thermal efficiency index of boilers is appropriately adjusted, and the thermal efficiency index of boilers burning inferior coal is cancelled (Table 6 of the 1995 edition: Tables 1 and 2 of this edition);
- The assessment requirements for excess air coefficient and exhaust temperature at the boiler exhaust are added (6.1.3 and 16.1.4 of this edition); the assessment requirements for boiler reliability are added (6.1.6 of this edition); the shelf life of boilers is appropriately adjusted (8.8 of the 1995 edition; 11.1 of this edition); the requirement that new products must be identified is cancelled (Chapter 7 of the 1995 edition). This standard is proposed by the China Machinery Industry Federation. This standard is under the jurisdiction of the National Technical Committee for Boiler Standardization (CSBTS/TC73). The responsible drafting unit of this standard is Shanghai Industrial Boiler Research Institute. The main drafter of this standard is Ye Mian.
This standard was first issued in 1995.
1 Scope
Technical conditions
Small boilers and normal pressure hot water boilers
JB/T7985—2002
This standard specifies the definition, parameter series, model compilation method, technical requirements, testing and inspection, marking and packaging, use conditions, normal pressure hot water boiler system and quality responsibility of small boilers and normal pressure hot water boilers. This standard is applicable to fixed small boilers and normal pressure hot water boilers made of low carbon steel with water as the medium. 2 Normative references
The clauses in the following documents become the clauses of this standard through reference in this standard. For any dated referenced document, all subsequent amendments (excluding errata) or revisions are not applicable to this standard. However, parties that reach an agreement based on this standard are encouraged to study whether the latest versions of these documents can be used. For any undated referenced document, the latest version is applicable to this standard. GB/T700 Carbon cable structural steel
GB1576 Industrial boiler water quality
GB/T2900.48 Electrical terminology Fixed boiler GB/T8163 Seamless steel pipe for conveying fluid
GB/T9222
Strength calculation of pressure components of water tube boiler
GB/T10180
GB13271
Industrial boiler thermal performance test procedures
Boiler air pollutant troubleshooting standards
GB/T16508
GB50041
GB50273
JB/ T1615
JB/T1620
JB/T1621
JB/T1626
Strength calculation of pressure components of shell boilers
Boiler room design code
Code for construction and acceptance of industrial boiler installation projects Technical conditions for boiler painting and packaging
Technical conditions for boiler steel structure
Technical conditions for industrial boiler smoke boxes and steel smoke windows Method for compiling industrial boiler product models
Safety supervision regulations for small and normal pressure hot water boilers 3 Terms and definitions
The terms and definitions established in GB/T2900.48 and the following terms and definitions apply to this standard. 3.1
Small type boilers
refers to small dual-purpose steam and water boilers, small hot water boilers and small steam boilers, namely: a) small dual-purpose steam and water boilers with a rated evaporation capacity (or rated thermal power) not exceeding 0.5t/h (or 0.35MW) and a rated working pressure not exceeding 0.04MPa; b) hot water boilers with a rated outlet water pressure not exceeding 0.1MPa and hot water boilers pressurized by tap water; c) small steam boilers with a water volume not exceeding 50L and a rated steam pressure not exceeding 0.7MPa. 3.2
Atmospheric hot water boilers Atmospheric hot water boilers Boiler bodies are opened or connected to the atmosphere by connecting pipes, and the gauge pressure at the top of the furnace body is zero in any case. JB/T7985—2002
4 Parameter series
4.1 The parameter range of small boiler products shall comply with the provisions of the "Regulations on Safety Supervision of Small and Atmospheric Pressure Hot Water Boilers", and the specific parameters shall be formulated by each manufacturing unit.
4.2 The rated thermal power of the pressurized hot water boiler shall not be less than 0.05MW and shall not be greater than 2.8MW, and the rated outlet water temperature shall not be greater than 85℃. 5 Model compilation method
5.1 The product model compilation method of small boilers shall comply with the compilation principles specified in JB/T1626. 5.2 The product model compilation method of atmospheric pressure hot water boilers shall comply with the compilation principles specified in JB/T1626, and the English capital letter C shall be added before the product model.
Example 1: CLSG0.35—WII represents a vertical water pipe fixed grate, a rated thermal power of 0.35MW, and an atmospheric pressure hot water boiler burning Class II anthracite. Example 2: CWDR1.4 represents a horizontal electric heating atmospheric pressure hot water boiler with a rated thermal power of 1.4MW. 5.3 If the boiler is a dual-purpose boiler for steam and hot water, the product model shall be compiled according to its main function as a steam or hot water boiler, and "dual-purpose steam and water" shall be written on the boiler name.
6 Technical requirements
6.1 Performance under rated conditions
6.1.1 The manufacturer shall ensure the rated evaporation capacity or rated thermal power of the boiler under the rated medium parameters. 6.1.2 When the fuel used meets the design requirements, the equipment is in good condition and operates correctly as required, the thermal efficiency index of the boiler shall meet the following provisions:
a) The thermal efficiency of layered combustion boilers shall not be lower than that specified in Table 1: b) The thermal efficiency of oil and gas boilers shall not be lower than that specified in Table 2: c) The thermal efficiency of electric heating boilers shall not be lower than 96%. 6.1.3 For boilers with layered combustion, the excess air coefficient at the exhaust should not be greater than 1.75; for oil and gas boilers, the excess air coefficient at the exhaust should not be greater than 1.2 during positive pressure combustion, and the excess air coefficient at the exhaust should not be greater than 1.3 during negative pressure combustion. 6.1.4 For boilers with rear heating surfaces, the exhaust temperature should not be greater than 170°C: for boilers without rear heating surfaces, the exhaust temperature should not be greater than 250°C.
6.1.5 The emission of atmospheric pollutants from boilers shall comply with the provisions of GB13271. 6.1.6 The number of forced shutdowns and overhauls caused by poor design and manufacturing quality of boilers and their factory-produced ancillary equipment during the warranty period shall comply with the following provisions:
a) For coal-fired boilers, it should not be more than three times; b) For oil, gas and electric heating boilers, it should not be more than two times. 6.2 Basic design requirements
6.2.1. The boiler design should make the product have good comprehensive technical and economic performance such as safety, reliability, economic efficiency, environmental protection, and easy use and maintenance.
The heating surface should be arranged reasonably during boiler design, and a good water circulation should be formed to ensure reliable cooling of the heating surface of each part. 6.2.2
During operation, each part should be able to expand freely in the design predetermined direction. 6.2.3 The boiler structure should have sufficient strength, rigidity and stability. The strength calculation of the boiler pressure components should be carried out in accordance with the provisions of GB/T9222 or GB/T16508. The wall thickness of the boiler shell (shell) or furnace should not be less than 3mm. 6.2.4 Oil and gas boilers should use matching oil and gas burners. 6.2.5 The combustion equipment of the mechanical layer combustion boiler should have good sealing performance and sufficient wind chamber wind pressure, and the air regulating device should be flexible and effective. 6.2.6 The furnace wall and smoke and air duct of the boiler should have good sealing performance and thermal insulation performance. The temperature of the outer surface of the boiler wall shall not be higher than 50℃, and the temperature of the outer surface of the boiler top shall not be higher than 70℃. 6.2.7 The boiler shall be easy to transport, install, operate, overhaul, drain, drain and clean inside and outside. 2
JB/T7985—2002
6.2.8 Small boilers shall be equipped with safety valves. The selection of safety valves shall comply with the provisions of the "Regulations on Safety Supervision of Small and Atmospheric Pressure Hot Water Boilers". The equivalent diameter D of the atmospheric connecting pipe of the atmospheric pressure hot water boiler shall be calculated as follows: 6.2.9
De=88V@
Where:
D. -Equivalent diameter, in mm:
Rated thermal power of the pressurized hot water boiler, in MW. Q
Table 1 Thermal efficiency of layered combustion boiler
Receiving base low calorific value of fuel
Fuel type
17700≤Qmtwm≤21000
Qstx>21000
Qes17700
Q≥21000
Q21000
D≤0.5t/h or Q<0.7MW
Boiler guard capacity (D or Q)
0.7MW≤Q≤1.4MW
Steam boiler thermal efficiency, %
1.4MW20%: lean coal, 10%37%, Table 2 Thermal efficiency of oil and gas boilers
Steam boiler
Fuel type
D≤0.5t/h
The thermal efficiency index of the furnace for fuels not listed in the table shall be agreed upon by the supply and demand parties. Note: "Gas" refers to natural gas, city gas and liquefied petroleum gas, 6.3 Manufacturing
6.3.1 Material requirements
Q≤1.4MW
Boiler thermal efficiency, %
Hot water boiler
1.4MW≤Q≤2.8MW
The materials for manufacturing the main parts such as the boiler body and the materials for welding rods and welding wires shall have quality certificates, and the materials of the pressure components of small boilers shall comply with the requirements of the "Regulations on Safety Supervision of Small and Atmospheric Pressure Hot Water Boilers". The steel plate material of the main parts such as the normal pressure hot water boiler body shall not be lower than the provisions of Q235 in GB/T700, and the steel pipe material shall not be lower than the provisions of No. 10 and No. 20 steel in GB/T8163. 6.3.2 Boiler drum (shell) and furnace manufacturing
6.3.2.1 The shortest section of the boiler shell (shell) and furnace shall not be less than 300mm, and there shall be no more than two longitudinal welds in each section of the boiler shell (shell), and the length of the outer arc between the center lines of the two longitudinal welds shall not be less than 300mm. The butt edge deviation of the circumferential weld shall not be greater than 10% of the nominal plate thickness plus 1mm, and the butt edge deviation of the longitudinal weld shall not be greater than 15% of the nominal plate thickness. 6.3.2.2 The difference between the maximum and minimum diameters of the boiler drum (shell) and furnace in the same section, and the correction angle shall not exceed the provisions of Table 3. Table 3 The difference between the maximum and minimum diameters of the same section of the boiler drum (shell) and furnace, and the edge angle nominal inner diameter D. mm
D,≤1000
1000≤D,≤1500
1500D,≤1800
D,>1800
Difference between the maximum and minimum diameters of the same section mm4
Angle
JB/T7985—2002
6.3.2.3 The head should be made of a whole piece of steel plate, and no more than two pieces should be spliced. 6.3.2.4 The boiler shell (), furnace and the connected head and tube sheet of small boilers (except small steam boilers) and atmospheric pressure hot water boilers can adopt a plug-in full-penetration T-type connection structure. 6.3.2.5 The row of pipe holes should not be opened on the weld. 6.3.3 Manufacture of headers
When the length of the header cylinder is not more than 2000mm, one butt weld is allowed; when the length of the header cylinder is more than 2000mm, two butt welds are allowed. When the header is spliced, the length of the shortest section should not be less than 500mm, and the butt edge deviation of the circumferential weld should not be more than 10% of the wall thickness plus 1mm
6.3.4 Manufacture of heating surface pipes
6.3.4.1 The bending radius of the pipe should not be less than 1.5 times the outer diameter of the pipe, and the bending angle deviation should not exceed 1.5*. 6.3.4.2 When the length of the heating surface pipe is not more than 2000mm, one butt weld is allowed; when the length of the heating surface pipe is more than 2000mm, two butt welds are allowed (except for serpentine pipes). When the pipes are spliced, the length of the shortest section should not be less than 500mm, and the pipe joint edge deviation should not exceed 10% of the pipe wall thickness plus 1mm. 6.3.5 Manufacturing of smoke windows and smoke boxes
The manufacturing of smoke windows and smoke boxes shall comply with the requirements of JB/T1621. 6.3.6 Manufacturing of boiler steel structures
The manufacturing of boiler steel structures shall comply with the requirements of JB/T1620. 6.3.7 Welding
6.3.7.1 The welding of boiler pressure components shall be evaluated in accordance with the provisions of the "Regulations on Safety Supervision of Small and Normal Pressure Hot Water Boilers", and a welding process instruction shall be formulated, and welding shall be carried out in accordance with the welding process instruction. 6.3.7.2 The size of the weld shall comply with the requirements of the drawings and process documents. 6.3.7.3 When the welding environment temperature is below 0℃, welding should not be carried out without preheating measures. Open-air welding should not be carried out in rainy, snowy and foggy weather. Before welding, oil, rust and other debris that may affect the welding quality should be cleaned up. 6.3.7.4 Weld quality requirements: The weld height should not be lower than the parent material, and the transition with the parent material should be smooth. There should be no cracks, arc pits or undercuts exceeding 0.5mm on the surface of the weld and heat-affected zone. 6.3.8 Assembly
6.3.8.1 The length of the pipe extending out of the weld connecting it to the tube sheet: When the smoke temperature is greater than 600℃, the length of the pipe extending out of the weld should not be greater than 1.5mm; when the smoke temperature is less than or equal to 600℃, the length of the pipe extending out of the weld should not be greater than 5mm. The length of the pipe extending into the inner wall of the header shall not be greater than 10mm
6.3.8.2 The inclination, offset and flange inclination of various pipe joints on the cylinder (shell), head and header shall not exceed 2mm6.4 Requirements for auxiliary machines and accessories for boilers
6.4.1 The auxiliary machines and accessories for boilers shall meet the performance requirements of the host products and comply with their product standards. 6.4.2 The water treatment equipment for boilers shall ensure that the water quality of boiler feed water complies with the provisions of GB1576. 6.4.3 The noise of auxiliary machines such as fans shall comply with their respective product standards, and the overall noise of the boiler room shall comply with the provisions of GB50041. 6.4.4 The flue gas purification equipment for boilers shall ensure that its atmospheric pollutant emissions comply with the provisions of GB13271. 6.5 Functional requirements for detection and monitoring instruments and devices6.5.1 Boilers shall be equipped with pressure gauges, water level gauges and other indicating instruments for safe operation parameters in accordance with the provisions of the "Regulations on Safety Supervision of Small and Normally Pressurized Hot Water Boilers".
6.5.2 Steam boilers shall be equipped with automatic water supply adjustment devices. 6.5.3 Steam boilers shall be equipped with extreme low water level and steam overpressure alarm and protection devices (except for natural ventilation hand-fired boilers). Hot water boilers shall be equipped with rated outlet water temperature over-temperature alarm and protection devices. Boiler mechanical combustion equipment shall also be equipped with fault shutdown alarm and protection devices. 6.5.4 In addition to the above instruments and devices, oil and gas boilers shall also be equipped with ignition sequence control, furnace flameout alarm and protection, oil temperature or gas pressure over-limit alarm and protection, combustion position or ratio automatic adjustment devices. 4
7 Inspection and testing
JB/T79852002
7.1 Material inspection
Inspect whether the materials and strips of the main components such as the boiler body and the materials of the welding wire meet the materials specified in the design drawings and technical documents and whether there are material quality certificates.
7.2 Quality inspection of main parts and assembly
The manufacturing quality inspection of main parts such as boiler shell, furnace, header, heating surface pipe, smoke box, smoke box and boiler steel structure and the quality inspection of assembly are carried out by conventional inspection methods such as measuring tools. 7.3 Welding quality inspection
The inspection of weld quality is carried out by measuring and visual inspection. For the welds of pressure components of small steam boilers, non-destructive testing should also be carried out in accordance with the relevant provisions of the "Regulations on Safety Supervision of Small and Normal Pressure Hot Water Boilers". 7.4 Water pressure test
After the boiler is assembled, a water pressure test should be carried out. The water pressure test pressure should be 1.5 times its rated working pressure, and the minimum should not be less than 0.2MPa. During the pressure test, the ambient air temperature should not be lower than 5℃, and the water temperature should not be lower than the dew point temperature. The pressure stabilization time is 20min. There are no water drops and water mist on the metal wall and weld of the pressure test component, and no residual deformation is found. The water pressure test is qualified. 7.5 Thermal performance
The thermal performance test of boilers shall be carried out in accordance with the provisions of GB/T10180. 7.6 Emission of air pollutants
The determination of the emission value of air pollutants of boilers shall be carried out in accordance with the monitoring standards specified in GB13271. Inspection and test rules
The quality inspection department of the boiler manufacturing unit shall conduct factory inspection of product quality for each unit in accordance with the provisions of this standard. The items and requirements of factory inspection 8.1
See Table 4. After passing the factory inspection, a quality certificate shall be issued. The content of the quality certificate shall include: Product certificate of boiler:
Main technical specifications:
Quality certificate of metal materials used in the main components of the boiler: c)
Combustion equipment cold test report or oil and gas boiler hot commissioning report (if hot commissioning is carried out at the user's site, it can be provided after commissioning):
Hydraulic pressure test report:
f) If non-destructive testing is carried out on the welds of small steam boilers, there shall also be a non-destructive testing report on the quality of the welds. New trial-produced boiler products and boiler products with major structural changes should undergo type tests. The items and requirements of type tests are shown in Table 4. 8.2
Material inspection
Table 4 Items and requirements for factory inspection and type tests Factory inspection
Main parts and assembly quality inspection
Welding quality inspection
Hydraulic pressure test
Thermal performance
Emission of air pollutants
Note: "√" indicates items that need to be done.
9 Paint, packaging, marking and accompanying documents
The paint and packaging of the boiler shall comply with the provisions of JB/T1615. 9.1
Type test
9.2 A metal nameplate should be installed at a conspicuous position on the boiler, and the content should at least include: Technical requirements
6.3.2~6.3.6,6.3.8
6.1.2~6.1.4
Inspection method
JB/T7985-2002
a) Product model and name:
Product number of manufacturing unit:
Rated steam pressure or rated water outlet pressure, in MPa: Rated thermal power or rated evaporation capacity, in MW or t/h: Rated water outlet temperature and return water temperature or rated steam temperature, in C: Name of manufacturing unit:
Manufacturing license level and number;
Name of inspection unit and inspection mark:
Date of manufacturing.
9.3 Atmospheric pressure hot water boilers should also be sprayed with a warning sign "Atmospheric pressure hot water boilers must not be used under pressure and the outlet hot water temperature must not exceed 90℃" on a conspicuous position on the furnace body.
9.4 The following drawings and technical documents should be provided when the boiler product leaves the factory: Product quality certificate: wwW.bzxz.Net
General drawing and installation drawing of the boiler, easy-to-photograph drawing, Atmospheric pressure hot water boilers should also provide piping system drawings: Strength calculation sheet of pressure components or summary table of calculation results, atmospheric connection pipe diameter calculation sheet of atmospheric pressure hot water boilers or safety valve discharge calculation sheet of small boilers, installation and operation instructions, notice of major design changes of pressure components: Packing list and spare parts list;
Other documents required to be provided as required:
List of the above drawings and technical documents
10 Installation and use requirements
The boiler installation should be carried out in accordance with the provisions of GB50273 standard and the boiler installation instructions of the manufacturer. 10.1
The boiler operation should be carried out in accordance with the provisions of the boiler operation instructions of the manufacturer. The fuel used in the boiler shall meet the requirements of the design regulations. 10.3
The water quality of boiler feed water and boiler water shall meet the requirements of GB1576. 10.5 The boiler operators shall be trained and shall operate according to the operating procedures. 11
No valves shall be installed on the atmospheric connecting pipe of the steel furnace in the normal pressure hot water boiler system
The system shall be equipped with a device to prevent the overflow of backwater when the pump is stopped. 11.3 For direct heating boilers, the circulating pump in the system shall be installed on the outlet side of the boiler. The system shall be equipped with an automatic or manual water replenishment device. 11.4
The system shall have reliable pressure setting measures and devices to protect the expansion or cooling of circulating water. The system shall have a device to prevent water hammer accidents caused by pump stop. In addition to the above provisions, the system shall also comply with the relevant provisions in GB50041. 12 Quality responsibility
The boiler manufacturer shall be responsible for the design and manufacturing quality of the product. Under the condition that the user complies with this standard and relevant technical documents, within 18 months from the date of the boiler leaving the factory or within 12 months from the date of formal operation (if the factory expiration date exceeds 18 months; if the operation period is less than 12 months, the factory expiration date shall prevail: if the factory expiration date is less than 18 months and the operation period exceeds 12 months, the operation period shall prevail), if the boiler cannot operate normally according to the rated parameters or fails to meet the specified performance requirements due to poor design and manufacturing or reasons other than installation quality, operating conditions and operating level, the manufacturer shall bear the corresponding responsibility.
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