HG/T 20589-1996 Chemical industrial furnace pressure component strength calculation regulations
Some standard content:
Industry Standard of the People's Republic of China
HG/T 20589—96
Specification of Strength Calculation on Pressure Parts for Chemical Process Furnace1996—09—10 Issued
1997--01—01
Ministry of Chemical Industry of the People's Republic of China
Ministry of Chemical Industry Document
Chemical Construction Development (1996) No. 632
Notice on Issuing the Industry Standard "Regulations on Strength Calculation of Pressure Components of Chemical Industrial Furnaces"
To all provincial, autonomous region, municipality directly under the Central Government, and independently planned cities, and all relevant design units: The "Regulations on Strength Calculation of Pressure Components of Chemical Industrial Furnaces" organized by the Industrial Furnace Design Technology Center of the Ministry of Chemical Industry and edited by the Design Institute of Nanhua (Group) Company has been reviewed and approved as a recommended industry standard, numbered HG/T20589-96 and will be implemented from January 1, 1997.
This regulation is managed by the Industrial Furnace Design Technology Center of the Ministry of Chemical Industry, and published and issued by the Engineering Construction Standard Editing Center of the Ministry of Chemical Industry.
Ministry of Chemical Industry
September 10, 1996
Industry Standard of the People's Republic of China
Strength Calculation Rules for Pressure-bearing Components of Chemical Industrial Furnaces HG/T 20589-96
Editor: Nanjing Chemical Industry (Group) Company Design Institute
Approval Department: Chemical
Implementation Date: January 1, 1997 Engineering Construction Standard Editing Center of the Ministry of Chemical Industry
so.com1 General Provisions
1.1 Scope of Application
1.2 Related Standards
1.3 Materials
2.1 Design Basis
2.2 Design Pressure··
2.3 Design Temperature
2.4 Safety Factor of Steel for Furnace Tubes
2.5 Wall Thickness addition
2.6 Screw change temperature
2.7 Mechanical properties of furnace tube steel
2.8 Stress formula···
2.9 Stress thickness
2.10 Minimum wall thickness and average wall thickness
2.11 Force verification of furnace tube
3 Junction (collecting pipe)
Special-shaped pipe fittings
4.1 Overview
4.2 Tee
4.3 Elbow
4.4 Equal diameter fork tube
4.5 Straight tube bending U-shaped tube.
Appendix A Auxiliary calculation of furnace tube Calculation
A.1 Maximum tube wall temperature of furnace tube:
A.2 Equivalent temperature of furnace tube wall·
A.3 Limit temperature of furnace tube·
A.4 Allowable stress of furnace tube material·
A.5 Corrosion fraction and minimum wall thickness of furnace tube..
A.6 Thermal stress limitation.
A.7 Calculation examples·
A.8 Furnace tube calculation table
Appendix B Internal pressure cylinder, head and components
-Electricity
B.1 Overview
B.2 Materials
Appendix C Unit conversion
Preparation instructions·
Reference materials
ECG Center of China
Quluqu
Pinxue Zhongzhong
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（3）
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（4）
（20)
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Zhongzhongzhuguozhongjie
：(27)
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.****. (64)
This regulation is used for the strength calculation of pressure-bearing components of chemical industrial furnaces. In addition to these regulations, the relevant parts shall comply with the laws, regulations and provisions on boilers and pressure vessels such as the "Safety Technical Supervision Regulations for Steam Boilers" and "Safety Technical Supervision Regulations for Pressure Vessels" issued by the state.
1.1 Scope of application
1.1.1 These regulations apply to the strength calculation of newly built chemical industrial furnaces without pressure parts. 1.1.2 These regulations apply to the strength calculation of the following direct flame heated chemical industrial furnace pressure components. 1.1.2.1 Design pressure is less than or equal to 24MPa, design temperature is less than or equal to 900℃, and the rolled furnace tubes are welded together with seamless steel pipes and pipe fittings rolled from carbon steel, alloy steel, stainless steel and heat-resistant steel. 1.1.2.2 Design pressure is less than or equal to 5MPa, design temperature is less than or equal to 1100℃, and the centrifugal casting furnace tubes are welded together with centrifugal casting heat-resistant alloy pipes and pipe fittings. 1.1.2.3 Pipe fittings made of carbon steel, alloy steel, stainless steel, heat-resistant steel, heat-resistant cast steel, carbon steel and alloy steel castings, such as manifolds, elbows, tees, fork pipes, tapered pipes, etc. 1.1.3 These regulations also apply to the strength calculation of cylinders, heads and components of newly built chemical industrial furnaces with internal pressure and refractory lining, such as gasifiers, secondary reformers, waste heat boiler pipe boxes, etc. 1.2 Related standards
1.2.1 Design regulations
1.2.1.1 Pipe systems with water and water vapor as media in pressure components shall be calculated in accordance with GB9222 "Strength Calculation of Pressure Components of Water Tube Boilers".
1.2.1.2 Strength calculation of cylinders, heads and components with internal pressure and refractory lining shall be calculated in accordance with the corresponding chapters of GB150 "Steel Pressure Vessels" when ensuring that they are not heated by direct flames, see Appendix B of these regulations. 1.2.2 Material requirements and referenced steel standards
HGJ 15
GB9948
GB8163
GB6479
GB5310
GB3087
GB2270
HG/T 2601
《Design and selection of metal materials for chemical industrial furnaces》《Materials selection regulations for steel chemical containers》《Seamless steel pipes for petroleum cracking》
《Seamless steel pipes for conveying fluids》
《High-pressure seamless steel pipes for fertilizer equipment》
《Seamless steel pipes for high-pressure boilers》
《Seamless steel pipes for low and medium-pressure boilers》
《Stainless steel seamless steel pipes》
《Technical conditions for centrifugal casting alloy furnace pipes for high-temperature pressure-bearing》1
SHJ 1041
GB4238
GB11352
GB2100
GB3274
GB4237
GB6654
GB6655
GB5681
GB7659
《Technical Requirements for Cr-25-Ni-12 Alloy Steel Castings for Tubular Heating Furnaces in Oil Refineries》《Heat-resistant Steel Plate》
《Casting Carbon Steel Parts for General Engineering》
《Stainless Acid-resistant Steel Castings》|| tt||《Technical Conditions for Ordinary Carbon Structural Steel and Low Alloy Structural Steel Sheets》《Hot-rolled Thick Plates and Strips of Carbon Structural Steel and Low Alloy Structural Steel》《Hot-rolled Stainless Steel Plates》
《Carbon Steel and Low Alloy Steel Thick Plates for Pressure Vessels》《Low Alloy Steel Plates for Multilayer Pressure Vessels》《Hot-rolled Steel Strips for Pressure Vessels》
《Carbon Steel Castings for Welded Structures》
1.2.3 Provisions for Manufacturing, Inspection and Acceptance
HG20545
JB1611
HG20544||tt ||JB1610
JB1612
CHJB301
HG20531
GB6414
GB5677
JB4726
JB4728
JB4729
JB4730
"Steel Pressure Vessels"
"Technical Conditions for Manufacturing Pressure Components of Chemical Industrial Furnaces""Technical Conditions for Manufacturing Boiler Headers"
"Technical Conditions for Structural Installation of Chemical Industrial Furnaces" 》《Technical conditions for the manufacture of boiler tubes》
《Technical conditions for the hydraulic test of boilers》
《Technical conditions for the manufacture of harp tubes for section furnace radiation sections》
《Cast steel and cast iron vessels》
《Dimensional tolerances of castings》
《Radiographic and film grade classification methods for steel castings》
《Carbon steel and low alloy steel forgings for pressure vessels》
《Spinning heads》
《Non-destructive testing of pressure vessels》
1.3.1 The steel used for pressure components of chemical industrial furnaces shall comply with these regulations. All steel used for non-pressure components welded to pressure components must also have good weldability. 1.3.2 Steel materials for pressure components must take into account the component operating conditions and design parameters (such as design temperature, design pressure, medium characteristics, etc.), material welding performance, cold and hot processing performance and economic rationality. 1.3.3 The quality and specifications of steel materials for pressure components shall comply with the latest version of the corresponding national standards, industry standards (departmental standards) or relevant technical conditions, and have a steel quality certificate (or its copy) issued by the steel manufacturer. 1.3.4 The standards and technical requirements used in this regulation shall be the latest version of national standards and industry standards. 2
This regulation applies to the strength calculation of thin-walled furnace tubes and centrifugal casting furnace tubes (the ratio of furnace tube wall thickness to furnace tube outer diameter is less than 0.15).
2.1 Design basis
2.1.1 Calculation parameters
When applying the calculation method of this chapter, the following data must be obtained as calculation parameters, namely: operating pressure, operating temperature, corrosion allowance, furnace tube material, etc.
In addition, the following data are required:
2.1.1.1 Design life;
2.1.1.2 Design temperature;
2.1.1.3 Temperature margin;
2.1.1.4 Corrosion fraction;
2.1.1.5 Whether to apply elastic range thermal stress limit. If any of the above five items cannot be obtained, the following data shall be used for calculation:2.1.1.6 Design life is calculated as 100,000 hours;2.1.1.7 Design temperature is the highest tube wall temperature or equivalent temperature plus temperature margin respectively:2.1.1.8 Temperature margin: 15℃ for internal pressure heated furnace tubes without chemical reaction; 30℃ for internal pressure heated furnace tubes with chemical reaction;
2.1.1.9 Corrosion fraction shall be obtained according to Figure A.5.1.3 in Appendix A.5;2.1.1.10 Use elastic range thermal stress limit. 2.1.2 Restrictions
2.1.2.1 The basic allowable stress of metal materials is only considered based on the yield strength and fracture strength of the material. 2.1.2.2 This calculation regulation only considers the uniform corrosion of the medium, while the adverse factors such as graphitization and carburization of the material structure are considered in the material selection and design temperature control. 2.1.2.3 This calculation regulation does not consider the effects of pulse tension and compression, yield or alternating thermal loads on the metal. 2.1.2.4 The design load only includes the internal pressure load. The stress limit caused by the dead weight of the pipe, the support method, thermal expansion, etc. is considered in the thermal stress verification within the elastic range. 2.1.3 Division of design range
According to whether the design temperature of the furnace tube is lower than the creep temperature or higher than the creep temperature, it is divided into the elastic design range (lower temperature) or the fracture design range (higher temperature).
When the temperature zone is near the intersection of the elastic allowable stress and the fracture allowable stress, both the elastic design and fracture design formulas need to be used, but the larger value is taken as the design adoption value. 3
2.2.1 Elastic design pressure
2.2 Design pressure
Within the elastic design range, the design pressure is 1.2 times the maximum working pressure. 2.2.2 Rupture design pressure
2.2.2.1Within the rupture design range, the design pressure shall be 1.1 times the maximum working pressure. 2.2.2.2 Take the difference between the pump outlet pressure Po and the system resistance drop △P of its furnace pipe calculation section as the rupture design pressure, and calculate it according to the following formula:
PPo—AP
Pp—Rupture design pressure, MPa;
Po—maximum working pressure of the pump outlet, MPaAP
Resistance drop from the pump outlet to the furnace pipe calculation section, MPa. 2.3 Design temperature
t=tm+ta
t=te+ta
Design temperature, °C;
tm Maximum tube wall temperature (calculated according to Appendix A.1), °C: t. — Equivalent temperature (calculated according to Appendix A.2), C: ta- — Temperature margin (taken according to 2.1.1.3), °C. 2.4 Safety factor of steel for furnace tubes
Considering the calculation error, the defects of the material itself, and the deviations in manufacturing, inspection and installation, etc., the safety factor is taken as follows based on the yield limit:
(1) Ferritic steel: ns=1.5;
(2) Austenitic steel: ns=1.1;
(3) At creep temperature: ng=1.0.
2.5 Wall thickness addition
The wall thickness addition C is determined by the following formula:
C-C+C2 or C
Ci—-Corrosion allowance, mm
C2—Negative thickness deviation of rolled furnace tube, mm; C. Loose layer thickness of centrifugal casting tube, mm. 2.5.1 Corrosion allowance
Select according to the material, design temperature, design life and corrosiveness of the operating medium of the selected furnace tube. In hydrogen atmosphere under high temperature and high pressure, steel is selected according to the provisions of Figure 2.5.1-1. Corrosion allowance C1=0. When the operating medium contains compounds of sulfur, hydrogen sulfide, vanadium and sodium, the selection of furnace tube material shall comply with HGJ41 "Design and Selection Regulations for Metal Materials of Chemical Industrial Furnaces". The corrosion allowance C is selected according to Figure 2.5.1-2, Figure 2.5.1-3 and Table 2.5.1 respectively.
The corrosion allowance C1 for oxidation corrosion is selected according to Figure 2.5.1-4. 2.5.2 Negative deviation of tube wall thickness of rolled furnace tubes Negative deviation of tube wall thickness of rolled furnace tubes, unless otherwise specified, C2 is selected according to the provisions of Table 2.5.2. 2.5.3 Thickness of loose layer of centrifugal casting tubes
2.5.3.1 The inner wall is calculated according to the loose layer after inner wall processing. For example: the loose layer after processing is 0mm, that is, C30mm. If the inner wall is not processed, take C: =1.6mm.
2.5.3.2 The outer wall is not processed, and its roughness is 0.8mm, that is, C3=0.8mm. If the outer wall is processed, take C=omm.
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Temperature, ℃
Figure 2.5.1-2 Average corrosion rate of high temperature hydrogen sulfide in the absence of hydrogen (containing 0.6% mercury)
500°C
400°C
500°C
400°C
0~5%Cr steel
Corrosion rate
>1. 27m0/a
0.31-1.27mm/a
<0.51mm/a
12%C steel
Corrosion rate
P0.254mm/a
0.127~0.254mm/a
≤0.127mm/a
18-8 steel
Corrosion rate
>0.127mm/a
6: 0254~0. 127mm/a7
o.0254mm/a
3.925.889.898
196294345
H,s partial pressure, 10-3MPa
Figure 2.5.1-3 Corrosion resistance of steel to H2S in H, medium1 The basic allowable stress of metal materials is only considered based on the yield strength and fracture strength of the material. 2.1.2.2 This calculation regulation only considers the uniform corrosion of the medium, while the adverse factors such as graphitization and carburization of the material structure are considered in the material selection and design temperature control. 2.1.2.3 This calculation regulation does not consider the effects of pulse tension and compression, yield or alternating thermal loads on the metal. 2.1.2.4 The design load only includes the internal pressure load. The stress limit caused by the dead weight of the pipe, the support method, thermal expansion, etc. is considered in the thermal stress verification within the elastic range. 2.1.3 Division of the design range
According to the furnace tube design temperature being lower than the creep temperature or higher than the creep temperature, it is divided into the elastic design range (lower temperature) or the fracture design range (higher temperature). When the temperature zone is near the intersection of the elastic allowable stress and the fracture allowable stress, both the elastic design and fracture design formulas need to be used, but the larger value is taken as the design adoption value. 3
2.2.1 Elastic design pressure
2.2 Design pressure
Within the elastic design range, the design pressure is 1.2 times the maximum working pressure. 2.2.2 Rupture design pressure
2.2.2.1Within the rupture design range, the design pressure shall be 1.1 times the maximum working pressure. 2.2.2.2 Take the difference between the pump outlet pressure Po and the system resistance drop △P of its furnace pipe calculation section as the rupture design pressure, and calculate it according to the following formula:
PPo—AP
Pp—Rupture design pressure, MPa;
Po—maximum working pressure of the pump outlet, MPaAP
Resistance drop from the pump outlet to the furnace pipe calculation section, MPa. 2.3 Design temperature
t=tm+ta
t=te+ta
Design temperature, °C;
tm Maximum tube wall temperature (calculated according to Appendix A.1), °C: t. — Equivalent temperature (calculated according to Appendix A.2), C: ta- — Temperature margin (taken according to 2.1.1.3), °C. 2.4 Safety factor of steel for furnace tubes
Considering the calculation error, the defects of the material itself, and the deviations in manufacturing, inspection and installation, etc., the safety factor is taken as follows based on the yield limit:
(1) Ferritic steel: ns=1.5;
(2) Austenitic steel: ns=1.1;
(3) At creep temperature: ng=1.0.
2.5 Wall thickness addition
The wall thickness addition C is determined by the following formula:www.bzxz.net
C-C+C2 or C
Ci—-Corrosion allowance, mm
C2—Negative thickness deviation of rolled furnace tube, mm; C. Loose layer thickness of centrifugal casting tube, mm. 2.5.1 Corrosion allowance
Select according to the material, design temperature, design life and corrosiveness of the operating medium of the selected furnace tube. In hydrogen atmosphere under high temperature and high pressure, steel is selected according to the provisions of Figure 2.5.1-1. Corrosion allowance C1=0. When the operating medium contains compounds of sulfur, hydrogen sulfide, vanadium and sodium, the selection of furnace tube material shall comply with HGJ41 "Design and Selection Regulations for Metal Materials of Chemical Industrial Furnaces". The corrosion allowance C is selected according to Figure 2.5.1-2, Figure 2.5.1-3 and Table 2.5.1 respectively.
The corrosion allowance C1 for oxidation corrosion is selected according to Figure 2.5.1-4. 2.5.2 Negative deviation of tube wall thickness of rolled furnace tubes Negative deviation of tube wall thickness of rolled furnace tubes, unless otherwise specified, C2 is selected according to the provisions of Table 2.5.2. 2.5.3 Thickness of loose layer of centrifugal casting tubes
2.5.3.1 The inner wall is calculated according to the loose layer after inner wall processing. For example: the loose layer after processing is 0mm, that is, C30mm. If the inner wall is not processed, take C: =1.6mm.
2.5.3.2 The outer wall is not processed, and its roughness is 0.8mm, that is, C3=0.8mm. If the outer wall is processed, take C=omm.
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Temperature, ℃
Figure 2.5.1-2 Average corrosion rate of high temperature hydrogen sulfide in the absence of hydrogen (containing 0.6% mercury)
500°C
400°C
500°C
400°C
0~5%Cr steel
Corrosion rate
>1. 27m0/a
0.31-1.27mm/a
<0.51mm/a
12%C steel
Corrosion rate
P0.254mm/a
0.127~0.254mm/a
≤0.127mm/a
18-8 steel
Corrosion rate
>0.127mm/a
6: 0254~0. 127mm/a7
o.0254mm/a
3.925.889.898
196294345
H,s partial pressure, 10-3MPa
Figure 2.5.1-3 Corrosion resistance of steel to H2S in H, medium1 The basic allowable stress of metal materials is only considered based on the yield strength and fracture strength of the material. 2.1.2.2 This calculation regulation only considers the uniform corrosion of the medium, while the adverse factors such as graphitization and carburization of the material structure are considered in the material selection and design temperature control. 2.1.2.3 This calculation regulation does not consider the effects of pulse tension and compression, yield or alternating thermal loads on the metal. 2.1.2.4 The design load only includes the internal pressure load. The stress limit caused by the dead weight of the pipe, the support method, thermal expansion, etc. is considered in the thermal stress verification within the elastic range. 2.1.3 Division of the design range
According to the furnace tube design temperature being lower than the creep temperature or higher than the creep temperature, it is divided into the elastic design range (lower temperature) or the fracture design range (higher temperature). When the temperature zone is near the intersection of the elastic allowable stress and the fracture allowable stress, both the elastic design and fracture design formulas need to be used, but the larger value is taken as the design adoption value. 3
2.2.1 Elastic design pressure
2.2 Design pressure
Within the elastic design range, the design pressure is 1.2 times the maximum working pressure. 2.2.2 Rupture design pressure
2.2.2.1Within the rupture design range, the design pressure shall be 1.1 times the maximum working pressure. 2.2.2.2 Take the difference between the pump outlet pressure Po and the system resistance drop △P of its furnace pipe calculation section as the rupture design pressure, and calculate it according to the following formula:
PPo—AP
Pp—Rupture design pressure, MPa;
Po—maximum working pressure of the pump outlet, MPaAP
Resistance drop from the pump outlet to the furnace pipe calculation section, MPa. 2.3 Design temperature
t=tm+ta
t=te+ta
Design temperature, °C;
tm Maximum tube wall temperature (calculated according to Appendix A.1), °C: t. — Equivalent temperature (calculated according to Appendix A.2), C: ta- — Temperature margin (taken according to 2.1.1.3), °C. 2.4 Safety factor of steel for furnace tubes
Considering the calculation error, the defects of the material itself, and the deviations in manufacturing, inspection and installation, etc., the safety factor is taken as follows based on the yield limit:
(1) Ferritic steel: ns=1.5;
(2) Austenitic steel: ns=1.1;
(3) At creep temperature: ng=1.0.
2.5 Wall thickness addition
The wall thickness addition C is determined by the following formula:
C-C+C2 or C
Ci—-Corrosion allowance, mm
C2—Negative thickness deviation of rolled furnace tube, mm; C. Loose layer thickness of centrifugal casting tube, mm. 2.5.1 Corrosion allowance
Select according to the material, design temperature, design life and corrosiveness of the operating medium of the selected furnace tube. In hydrogen atmosphere under high temperature and high pressure, steel is selected according to the provisions of Figure 2.5.1-1. Corrosion allowance C1=0. When the operating medium contains compounds of sulfur, hydrogen sulfide, vanadium and sodium, the selection of furnace tube material shall comply with HGJ41 "Design and Selection Regulations for Metal Materials of Chemical Industrial Furnaces". The corrosion allowance C is selected according to Figure 2.5.1-2, Figure 2.5.1-3 and Table 2.5.1 respectively.
The corrosion allowance C1 for oxidation corrosion is selected according to Figure 2.5.1-4. 2.5.2 Negative deviation of tube wall thickness of rolled furnace tubes Negative deviation of tube wall thickness of rolled furnace tubes, unless otherwise specified, C2 is selected according to the provisions of Table 2.5.2. 2.5.3 Thickness of loose layer of centrifugal casting tubes
2.5.3.1 The inner wall is calculated according to the loose layer after inner wall processing. For example: the loose layer after processing is 0mm, that is, C30mm. If the inner wall is not processed, take C: =1.6mm.
2.5.3.2 The outer wall is not processed, and its roughness is 0.8mm, that is, C3=0.8mm. If the outer wall is processed, take C=omm.
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Temperature, ℃
Figure 2.5.1-2 Average corrosion rate of high temperature hydrogen sulfide in the absence of hydrogen (containing 0.6% mercury)
500°C
400°C
500°C
400°C
0~5%Cr steel
Corrosion rate
>1. 27m0/a
0.31-1.27mm/a
<0.51mm/a
12%C steel
Corrosion rate
P0.254mm/a
0.127~0.254mm/a
≤0.127mm/a
18-8 steel
Corrosion rate
>0.127mm/a
6: 0254~0. 127mm/a7
o.0254mm/a
3.925.889.898
196294345
H,s partial pressure, 10-3MPa
Figure 2.5.1-3 Corrosion resistance of steel to H2S in H, medium2 The outer wall is not processed, and its roughness is 0.8mm, that is, C3=0.8mm. The outer wall is processed, and C=omm.
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ONS OOA
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Temperature, ℃
Figure 2.5.1-2 Average corrosion rate of high-temperature hydrogen sulfide in the absence of hydrogen (containing 0.6% mercury)
500
400
500
400
0~5%Cr steel
Corrosion rate
>1. 27m0/a
0.31-1.27mm/a
<0.51mm/a
12%C steel
Corrosion rate
P0.254mm/a
0.127~0.254mm/a
≤0.127mm/a
18-8 steel
Corrosion rate
>0.127mm/a
6: 0254~0. 127mm/a7
o.0254mm/a
3.925.889.898
196294345
H,s partial pressure, 10-3MPa
Figure 2.5.1-3 Corrosion resistance of steel to H2S in H, medium2 The outer wall is not processed, and its roughness is 0.8mm, that is, C3=0.8mm. The outer wall is processed, and C=omm.
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ONS OOA
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Temperature, ℃
Figure 2.5.1-2 Average corrosion rate of high-temperature hydrogen sulfide in the absence of hydrogen (containing 0.6% mercury)
500
400
500
400
0~5%Cr steel
Corrosion rate
>1. 27m0/a
0.31-1.27mm/a
<0.51mm/a
12%C steel
Corrosion rate
P0.254mm/a
0.127~0.254mm/a
≤0.127mm/a
18-8 steel
Corrosion rate
>0.127mm/a
6: 0254~0. 127mm/a7
o.0254mm/a
3.925.889.898
196294345
H,s partial pressure, 10-3MPa
Figure 2.5.1-3 Corrosion resistance of steel to H2S in H, medium
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