Some standard content:
Machinery Industry Standard of the People's Republic of China
JB/T673683
Guidelines for Design of Boiler Steel Frame
Published on August 21, 1993
Published by the Ministry of Machinery Industry of the People's Republic of China and implemented on October 1, 1993
Subject Content and Scope of Application
Cited Standards
Main Symbols
Basic Provisions
Design Provisions
Material and Strength Design Values
Frame Layout
Frame Classification
Layout Principles -| |tt||Component arrangement·
Load statistics and distribution·
.....+.
Load classification and value provisions
Load effect combination:
Load statistics
Load distribution
Static analysis..
Calculation diagram of the frame
Horizontal support
Simplification of the calculation diagram of the frame.
Utilization of symmetry,
Selection of manual calculation framework analysis method.
Design and calculation of beams
Beam cross section||tt ||Strength calculation of beams
Overall stability of beams
Local stability of beams
Torsion calculation of beams
Construction requirements of beams
Design and calculation of columns
Cross-section of columns
Slenderness ratio of columns
Calculation of columns
Calculation of tie materials for two-legged lattice columns
Calculation of column shaft welds
Local stability
Calculation of column heads
Calculation of column foot
000.......0
(15）
11.9 Structural requirements
12 Truss design and calculation
12.1 Cross-sectional form of truss members
12.2 Truss member calculation
12.3 Vertical truss calculation
12.4 Furnace roof beam support system
12.5 Horizontal truss
12.6 Structural requirements
13 Connection design
Weld connection
High-strength bolt connection
Node design
Appendix A
Appendix B
Appendix C
Appendix D
Appendix E
Appendix F
Appendix G
Appendix H
Appendix 1
Appendix L
Appendix M
Appendix N
Appendix 0
Appendix P
Appendix Q
Appendix R
Appendix S
Appendix T
Appendix U
Appendix V
Appendix W
Appendix X
Steel Material Properties (Guaranteed Items) (Supplement) Steel pipe and water density table (Supplement)
Insulation material and accessories weight table (Supplement) Maximum allowable height of light furnace wall guard plate (Supplement) ..... Common cross-section mechanical properties (Supplement)
Single-span beam calculation formula (Supplement)
Single-span simply supported beam conversion mid-span concentrated force (Supplement) ... Variable section beam deflection calculation formula (Supplement) Shape constants of several basic rods (Supplement). Continuous beam calculation (Supplement)
Single-layer frame calculation chart (Supplement)
Overall stability coefficient of beam ( Supplement)·
Calculation of local stability of beam web (supplement) Calculation length coefficient of column (supplement)
Stability coefficient of axially compressed member (supplement)…·Relationship curve between spring coefficient of multi-elastic support column support and column calculation length coefficient value (supplement)…Design value of local strength of concrete (supplement) Selection table of Q235 steel and 16Mn steel bolts (supplement) International steel specifications (supplement)…
Combined section characteristics of components (supplement): Classification of basic seismic intensity and basic earthquake intensity in major cities across the country (reference) Outdoor meteorological parameters of the region (reference) Truss static analysis (hand calculation) (reference)
Frame static analysis (hand calculation) (reference)...(54)
........
Standard of the Machinery Industry of the People's Republic of China
Guidelines for the Design of Boiler Steel Frames
JB/T6736—93
This standard is formulated to implement the national technical and economic policies in the design of boiler steel frames, so that the boiler frame design can be safe, reliable, technologically advanced and economically reasonable while meeting the requirements of boiler equipment. Subject content and scope of application
This standard proposes the principles and regulations for frame design layout and material selection, and provides methods for load statistics and distribution, structural force analysis, and design calculation of components and connections.
This standard is applicable to the design of supported and suspended boiler frames and other similar equipment steel structures. 2 Reference standards
Technical conditions for high-quality carbon structural steel
Carbon structural steel
Hot-rolled I-beam
Hot-rolled ordinary channel steel
Basic types of weld grooves for gas welding, manual arc welding and gas shielded welding Basic types and dimensions of weld grooves for submerged arc welding GB1228~1231 Dimensions and technical conditions for high-strength large hexagonal head bolts, large hexagonal nuts and washers for steel structures GB1300
GB1 591
GB3077
GB3632
GB3633
GB5117
GB5118
GB5293
GB9787
GB9788
GB11352
ZB5339
Main symbols
Steel wire for welding
Low alloy structural steel| |tt||Technical conditions for alloy structural steel
Torsion shear type high strength bolt connection for steel structureTorsion shear type high strength bolt connection for steel structureCarbon steel welding rod
Low alloy steel welding rod
Flux for submerged arc welding of carbon steel
Type and size
Technical conditions
Dimensions, shape, weight and allowable deviation of hot-rolled equal angle steelDimensions, weight and allowable deviation of hot-rolled unequal angle steelCasting carbon steel for general engineering||tt ||Building structure load code
Building seismic design code
Steel structure design code
Unified standard for building structure design
Hot-rolled light I-beam
Hot-rolled light channel steel
Boiler seismic design standard
Action and effect
Approved by the Ministry of Machinery Industry on August 21, 1993
Implementation on October 1, 1993
Bending and torsion double moment ：
Concentrated load;
Bending moment;
Free torsion moment;
Axial force;
JB/T6736—93
Pretension of high-strength bolts; Recoil force of safety valve; Uniformly distributed load density;
Support reaction force;
Design value of load effect combination;
Standard value of horizontal earthquake effect;
Standard value of live load effect;||tt ||Standard value of permanent load (constant load) effect; S,—Standard value of wind load effect;
—Deflection;
—Shear force;
Standard value of wind load;
—Basic wind pressure;
3.2. Calculation index
Elastic modulus of steel,
Design value of tensile, compressive and flexural strength of steel; Design value of axial compressive strength of concrete; fe
End bearing pressure of steel Strength design value;
Design value of local bearing strength of concrete;f,
f,,f
Design value of tensile, shear and compressive strength of high-strength bolts; Design value of tensile, shear and compressive strength of a pair of butt welds; Design value of shear strength of steel;
fDesign value of tensile, shear and compressive strength of fillet welds;f
Yield strength (or servitude point) of pot materials;
Shear modulus of steel;|| tt||Euler critical force;
N, N, N-
Design value of tensile, shear and compressive bearing capacity of each high-strength bolt; normal stress,
local compressive stress;
stress perpendicular to the length direction of the fillet weld, calculated according to the effective section; shear stress:
shear stress along the length direction of the fillet weld;
free torsion shear stress;
[U]——allowable deflection of the beam;
3.3 Geometric parameters
Rough cutting area;
A end face pressure area;
A—effective area;
A—compression flange cross-sectional area;
A. —Net cutting area;
—spacing;
—width;
JB/T6736—93
b, b,—flange width or free overhang width of plate; b. —Width of box section flange plate between webs; b,—overhang width of stiffener;
d——diameter:
d. Effective diameter;
d. Aperture:
Height:
Full height of section;
h—effective thickness of fillet weld;
leg size of fillet weld;
Calculated height of web;
Economic height of beam;
Height of web:
Gross section moment of inertia;
Net section moment of inertia;
Fan moment of inertia;
Section radius of gyration;
Length or span;
Calculated length;
Calculated length of weld;
Assumed distribution length of concentrated load on the edge of calculated height of rubber plate; Gross section area torch,
t, t'——plate thickness and furnace wall thickness degree
—thickness of stiffening ribs;
thickness of web;
resistance moment of gross section;
resistance moment of net section;
-angle:
>—slenderness ratio:
in—converted slenderness ratio;
maximum sector area;
3.4 Calculation coefficient and others
C, C—dimensional parameters used to calculate the local stability of beam webs; number of bolts;
the number of high-strength bolts on a calculated section; n
the number of friction surfaces for transmitting force of high-strength bolts: -the number of shear surfaces of bolts;
structural importance coefficient;
natural vibration period of the frame;||tt| |Linear expansion coefficient;
%—Stress distribution unevenness coefficient of column web;: Beam web flattening and tightening coefficient;
β—--Wind vibration coefficient;
Equivalent bending moment coefficient of overall stability of beam;
JB/T6736-93
B—Increase coefficient of strength design value of front fillet weld; P, B
-Equivalent bending moment coefficient of stability of compression-bending member; B——Wind vibration coefficient at Z height;
β——Increase coefficient of strength design value of converted stress; Influence coefficient of bending normal stress on local stability of beam web;6
Influence coefficient of asymmetric beam section;
Anti-slip coefficient of friction surface of high-strength bolt ; Calculation length coefficient of column; Wind load shape coefficient;
Wind pressure height variation coefficient,
Pulsation influence coefficient;
Parameters used to calculate the overall stability of the beam; Pulsation increase coefficient; Width-thickness ratio of the web compression plate section of the beam;
Stability coefficient of axial compression member;
Overall stability coefficient of the beam;
Mode coefficient;
Concentrated load increase coefficient;
Combination coefficient of variable load;
Combination coefficient of wind load;
A:
Basic provisions
The design frame must be closely coordinated with the requirements of the boiler body, auxiliary equipment, plant layout, transportation and installation. It must be ensured that the frame has sufficient strength, rigidity and stability during the operation, installation and maintenance of the boiler. For the frame that requires earthquake protection, unless otherwise required, the earthquake resistance design of the frame shall be in accordance with ZB5339 standard. 4.3
Domestic materials should be used as much as possible to reduce the variety and specifications of materials. 4.4
Under the conditions of transportation, the design of the frame should expand the assembly as much as possible. 4.5
Except for special requirements, the design of the frame does not consider directly bearing dynamic loads. 4.6
When arranging the frame, the components should be kept away from high temperature (above 150℃) as much as possible. For components that must be arranged in the flue or subjected to high temperature for a long time, in addition to selecting suitable steel materials, necessary insulation or cooling measures should be taken. 4.8 When applying the above-mentioned reference standards, the particularity of the boiler frame that is different from other general building structures should be fully considered. 5 Design regulations
5.1 This standard adopts the limit state design method and designs the frame according to the limit state of bearing capacity and the limit state of normal use. 5.2 When calculating the strength, stability and connection strength of the structure or component, the load design value should be used; when calculating the deformation, the load standard value should be used.
5.3 The relative horizontal displacement allowed by the frame shall be adopted in accordance with the provisions of Table 1: 4
Load category
Permanent load
Wind load
JB/T6736-93
The ratio of the horizontal displacement between each layer and the top of the frame to the layer height or total height00
Geoclimatic action
The relative uneven settlement of the foundation shall not be greater than 0.2% of the adjacent column distance. 5.4
5.5 Unless otherwise specified, the structural importance coefficient is %. Generally, it is taken as 1.0. 5.6 When considering the combination of seismic action, the design value of the member material strength is increased by 25%. 6
Material and strength design value
6.1 Material
The grades and standards of commonly used steel for boiler frame are shown in Table 2Table
Carbon structural steel
Low alloy structural steel
Casting carbon steel
Material grade
ZG230-450
2G270500
According to the use requirements, boiling steel or killed steel can be selected. Not more than 50
GB1591
GG11352
The selected welding material should ensure that the weld metal has mechanical properties not lower than that of the basic metal. The large welding material can be selected according to Table 3.
Basic metal
Q235 or
(Q235 and 16Mn）
Manual welding
E50××
GB5117
GB5118
Automatic welding
H08MnA
H10Mn2
GB1300
GB5293
The high-strength bolt connection pair used for connection shall meet the requirements of GB1228~1231 or GB3632~3633 standards. The performance grades and steels recommended by 6.1.4
are shown in Table 4.
HRC35~45
For the specifications and standards of commonly used steel, see Table 5
20MnTiB
45, 35
45, 35
GB3077
≤M24
≤M22
I-beam
JB/T6736—93
GB9787
GB9788
6.1.6 Load-bearing structural steel
6.1.6.1 The mechanical properties and chemical composition of load-bearing structural steel must have the guarantee of compliance with the standards, and if necessary, the cold bending test should also have the guarantee of qualification.
Main load-bearing components with a calculated temperature equal to or lower than -20℃ should not use boiling steel. 6.1.6.2
When the plate thickness or steel section thickness of the main load-bearing components is greater than 40mm, the raw materials should be supplied in the normalized state. 6.1.6.3
For thick plates of main load-bearing components arranged outdoors and in extremely cold areas; if there are no effective protective measures, the non-plastic transition temperature (NDT) of the steel should be lower than the lowest temperature that may occur during use. 6.1.7 Selection of component materials
6.1.7.1·In load-bearing components and connections, steel plates and angle steels with a thickness of less than 5mm, and steel pipes with a thickness of less than 3mm should not be used. Component materials should be selected according to Table 6 based on the importance of the component, load characteristics, connection methods, calculation temperature, etc. 6.1. 7.2
Component name
Main beam and beam with height ≥ 2m
8. Tension flange
b. Carbon structural steel with flange thickness t≥40mmc.Low alloy structural steel general beams, columns and supports with wing plate thickness t36mm
Non-load-bearing components
Main beam support
Main material grade
≤-20c
>-20℃
Q235-B
Q235-A
Q235-A·F
Q235-A·F
Q215-A
Q235-A
ZG230—450
ZG270—500||tt ||Steel material guarantee items
Tensile strength, yield point, elongation, cold bending, room temperature impact, carbon, sulfur, phosphorus content
Same as above, Q235 steel should have a qualified guarantee of 20℃ impact toughness; 16Mn steel should have a qualified guarantee of 40℃ impact toughness
Tensile strength, yield point, elongation, carbon, sulfur, phosphorus content
Carbon, sulfur, phosphorus content
Tensile strength, yield point, elongation, carbon, sulfur, phosphorus content
Note: The calculation temperature should be based on the current national "Heating, Ventilation and Air Conditioning The outdoor calculation temperature of winter air conditioning specified in the "Design Code for Sections" is determined (Appendix V For indoor steel furnaces, it can be increased by 10°C according to this regulation. Material substitution
Among the items guaranteed by the mechanical properties of steel, only one of them is unqualified: 6.1.8.1
If the elongation is within 3% lower than the value specified in the standard, it is allowed to be used; if the service point is within 5% lower than the value specified in the standard, its strength design value can be reduced according to the service point ratio; impact toughness is not allowed to be reduced;
Substitution provisions when the material specifications do not meet the requirements of the drawings: The chemical composition and mechanical properties of the substitute materials should be consistent with the original design drawings or at the same level; the strength, rigidity and stability of the components should be reviewed in detail. When different materials are substituted, the fusion welding metal materials need to be modified accordingly. :
Strength design value
JB/T673693
The strength design value of steel should be adopted according to Table 7 based on the thickness or diameter of the steel, and the strength design value of steel castings should be adopted according to Table 8. The strength design values of welds and bolted connections should be adopted according to Tables 9 and 10. Table 7
ZG200—400||tt| |ZG230—450
ZG270—500
ZG310—570
Splicing method
Electrode type
Automatic welding, semi-automatic welding and
with E43X× type welding rod
Manual welding
Automatic welding, semi-automatic welding and
with E50×× type welding rod
Manual welding
Thickness or diameter
>16~40
>40~60
>60~100
>100~150
55~100
Tensile, compression, bending f
Tensile, compression and bending
Thickness or diameter
>16~40
>40~60
>60~100
>100~150
55~100
Shear f,
Strength design value of steel castings
Shear f,
Strength design value of welds
Butt welds| |tt||The weld pressure is as follows:
Tensile and bending
First level, second level
End face pressure (flattened top tightening)f
End face pressure (planed top tightening)fa
Fillet weld
Tensile, bending
and shear
Material grade of bolts
(or performance grade)
and material number of components
Pressure-bearing high-strength bolts
Component steel
JB/T6736—93
Bolt Strength design value of connection
C-grade bolt
Note: Holes with the following hole wall quality are classified as Class 1 holes: &
Class A and Class B bolts
① Holes drilled on assembled components according to the designed hole diameter; ② Holes drilled on individual parts and components according to the designed hole diameter by using a drill: Anti-
(Class 1 hole)
(Class 1 hole)
Pressure-bearing high-strength bolts
④ Holes drilled or punched with a smaller hole diameter on individual parts, and then expanded to the designed hole diameter on the assembled components. The strength design value of angle steel connected on one side and high-altitude installation welds with poor construction conditions should be multiplied by the corresponding reduction factor, and the reduction factor 6.2.3
is adopted according to Table 11.
Table 11 Reduction coefficient of strength design value
Structural member or connection condition
Calculation of strength and connection based on axial force
Equal angle steel
Single angle steel connected by single rain
Calculation of stability based on axial pressure
High-altitude installation welds with poor construction conditions
Unequal angle steel connected by short sides
Unequal angle steel connected by long sides
Reduction coefficient| |tt||0.06+0.0015入
及≤1.0
0.5+0.0025入
及≤1.0
Note: ①入 is the slenderness ratio. For single angle steel compression rod without connection in the middle, it should be calculated according to the minimum turning radius; when 入<20, 入=20②When several situations exist at the same time, the reduction factor should be multiplied. The physical properties and temperature influence of steel and steel castings shall be adopted according to Table 12 and Table 13. 6.2.4
Frame layout
7.1 Classification of frames
Frame-type frame (Figure 1) is generally used for medium and small capacity boilers, and rigid connections are adopted between components; truss-type frame (Figure 2) is generally used for large capacity suspended boilers, and hinged connections or rigid connections are adopted between components: b..
c. Mixed frame (Figure 3) is generally used for medium and small capacity boilers with the furnace chamber partially suspended and the rear heating surface partially supported. The frame is composed of frame type and truss type.
Strength design value
JB/T673693
The strength design value of steel should be adopted according to Table 7 based on the thickness or diameter of the steel, and the strength design value of steel castings should be adopted according to Table 8. The strength design value of welds and bolted connections should be adopted according to Tables 9 and 10. Table 7
ZG200—400
ZG230—450
ZG270—500
ZG310—570
Jointing method
Electrode type
Automatic welding, semi-automatic welding and
with E43X× type welding rod
Manual welding
Automatic welding, semi-automatic welding and
with E50×× type welding rod
Manual welding
Thickness or diameter
>16~40
>40 ~60
>60~100
>100~150
55~100
Tensile, compression, bending f
Tensile, compression and bending
Thickness or diameter
>16~40
>40~60
>60~100
>100~150
55~100
Shear f,
Strength design value of steel castings
Shear f,
Strength design value of welds
Butt weld
The weld pressure is as follows:
Tensile and bending
First level, second level
End face pressure (flattened top tight)f
End face pressure (planed top tight)fa
Fillet weld
Tensile, bending
and shear
Material grade of bolts
(or performance grade)
and material number of components
Pressure-bearing high-strength bolts
Component steel
JB/T6736—93|| tt||Strength design value of bolt connection
C-grade bolts
Note: Holes with the following hole wall quality are classified as Class 1 holes: &
Class A and Class B bolts
①Hole drilled on the assembled component according to the designed hole diameter; ②Hole drilled on individual parts and components according to the designed hole diameter:
(Class 1 hole)
(Class 1 hole)
Pressure-bearing high-strength bolts
④Hole drilled or punched with a smaller hole diameter on a single part, and then expanded to the designed hole diameter on the assembled component. For angle steel connected on one side and high-altitude installation welds with poor construction conditions, the strength design value should be multiplied by the corresponding reduction factor, and the reduction factor is adopted according to Table 11.
Table 11 Reduction coefficient of strength design value
Structural member or connection condition
Calculation of strength and connection based on axial force
Equal angle steel
Single angle steel connected by single rain
Calculation of stability based on axial pressure
High-altitude installation welds with poor construction conditions
Unequal angle steel connected by short sides
Unequal angle steel connected by long sides
Reduction coefficient| |tt||0.06+0.0015入
及≤1.0
0.5+0.0025入
及≤1.0
Note: ①入 is the slenderness ratio. For single angle steel compression rod without connection in the middle, it should be calculated according to the minimum turning radius; when 入<20, 入=20②When several situations exist at the same time, the reduction factor should be multiplied. The physical properties and temperature influence of steel and steel castings shall be adopted according to Table 12 and Table 13. 6.2.4
Frame layout
7.1 Classification of frames
Frame-type frame (Figure 1) is generally used for medium and small capacity boilers, and rigid connections are adopted between components; truss-type frame (Figure 2) is generally used for large capacity suspended boilers, and hinged connections or rigid connections are adopted between components: b..
c. Mixed frame (Figure 3) is generally used for medium and small capacity boilers with the furnace chamber partially suspended and the rear heating surface partially supported. The frame is composed of frame type and truss type.
Strength design value
JB/T673693
The strength design value of steel should be adopted according to Table 7 based on the thickness or diameter of the steel, and the strength design value of steel castings should be adopted according to Table 8. The strength design value of welds and bolted connections should be adopted according to Tables 9 and 10. Table 7
ZG200—400
ZG230—450
ZG270—500
ZG310—570
Jointing method
Electrode type
Automatic welding, semi-automatic welding and
with E43X× type welding rod
Manual welding
Automatic welding, semi-automatic welding and
with E50×× type welding rod
Manual welding
Thickness or diameter
>16~40
>40 ~60
>60~100
>100~150
55~100
Tensile, compression, bending f
Tensile, compression and bending
Thickness or diameter
>16~40
>40~60
>60~100
>100~150
55~100www.bzxz.net
Shear f,
Strength design value of steel castings
Shear f,
Strength design value of welds
Butt weld
The weld pressure is as follows:
Tensile and bending
First level, second level
End face pressure (flattened top tight)f
End face pressure (planed top tight)fa
Fillet weld
Tensile, bending
and shear
Material grade of bolts
(or performance grade)
and material number of components
Pressure-bearing high-strength bolts
Component steel
JB/T6736—93|| tt||Strength design value of bolt connection
C-grade bolts
Note: Holes with the following hole wall quality are classified as Class 1 holes: &
Class A and Class B bolts
①Hole drilled on the assembled component according to the designed hole diameter; ②Hole drilled on individual parts and components according to the designed hole diameter:
(Class 1 hole)
(Class 1 hole)
Pressure-bearing high-strength bolts
④Hole drilled or punched with a smaller hole diameter on a single part, and then expanded to the designed hole diameter on the assembled component. For angle steel connected on one side and high-altitude installation welds with poor construction conditions, the strength design value should be multiplied by the corresponding reduction factor, and the reduction factor is adopted according to Table 11.
Table 11 Reduction coefficient of strength design value
Structural member or connection condition
Calculation of strength and connection based on axial force
Equal angle steel
Single angle steel connected by single rain
Calculation of stability based on axial pressure
High-altitude installation welds with poor construction conditions
Unequal angle steel connected by short sides
Unequal angle steel connected by long sides
Reduction coefficient| |tt||0.06+0.0015入
及≤1.0
0.5+0.0025入
及≤1.0
Note: ①入 is the slenderness ratio. For single angle steel compression rod without connection in the middle, it should be calculated according to the minimum turning radius; when 入<20, 入=20②When several situations exist at the same time, the reduction factor should be multiplied. The physical properties and temperature influence of steel and steel castings shall be adopted according to Table 12 and Table 13. 6.2.4
Frame layout
7.1 Classification of frames
Frame-type frame (Figure 1) is generally used for medium and small capacity boilers, and rigid connections are adopted between components; truss-type frame (Figure 2) is generally used for large capacity suspended boilers, and hinged connections or rigid connections are adopted between components: b..
c. Mixed frame (Figure 3) is generally used for medium and small capacity boilers with the furnace chamber partially suspended and the rear heating surface partially supported. The frame is composed of frame type and truss type.
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