CN108228992A - lightning rod flange design method and terminal device - Google Patents
lightning rod flange design method and terminal device Download PDFInfo
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- CN108228992A CN108228992A CN201711445094.3A CN201711445094A CN108228992A CN 108228992 A CN108228992 A CN 108228992A CN 201711445094 A CN201711445094 A CN 201711445094A CN 108228992 A CN108228992 A CN 108228992A
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Abstract
The present invention relates to lightning rod technical fields, provide lightning rod flange design method and terminal device.This method includes：The relevant information for the lightning rod that collapses is obtained to analyze the reason of lightning rod collapses, according to the relevant information for the lightning rod that collapses, with AR autoregression technologies, based on Davenport spectrum analog wind loads, horizontal and vertical correlation is considered simultaneously, the wind load time-history sample of various structure type lightning rods is obtained, further according to the wind load time-history sample of various structure type lightning rods, the stress performance of lightning rod flange is analyzed, and lightning rod flange is optimized according to analysis result.Above-mentioned lightning rod flange design method and terminal device can optimize lightning rod flange analysis, promote the wind resistance of lightning rod, ensure the safe operation of lightning rod.
Description
Technical field
The invention belongs to lightning rod technical field more particularly to lightning rod flange design method and terminal devices.
Background technology
Lightning rod belongs to tall and slender structure, and natural vibration period is big, and dynamic response is quite notable under the action of wind load, absolutely mostly
Only by wind action in the case of number, therefore, lightning rod is influenced very big by wind load.
Lightning rod in substation is taken up an area, the overwhelming majority is all erected in each voltage mostly using single steel pipe structure to save
On grade truss column, particularly power distribution equipment is by AIS to HGIS again to during GIS, and the height of lightning rod is according to electrical anti-
Thunder calculates requirement, becomes higher and higher.By taking 220kV outlet structures in 220kV substations (using GIS power distribution equipments) as an example, structure
Frame height is optimized to the 14m that current allusion quotation sets by pervious 15m, and terminal height is then increased to 46m or even 50m, A word column from 35m
Upper single steel pipe lightning rod is up to 32m or even 36m, in most cases also simultaneous hanging ground-wire, and lightning rod at this time is still routinely
It is designed, compared with the thinner A word columns in lower part, there is the phenomenon that apparent " top-heavy ".
Also it is mostly the lightning rod erected on framework A word columns in view of the lightning rod falling accident that currently occurs, on framework
Whether portion's single steel pipe lightning rod is influenced by lower part A word columns, if it is influenced by conducting wire, ground wire, under wind action,
Whether dynamic effect of the lightning rod under wind action, which has, is further amplified, and is worth further further investigation.
Invention content
In view of this, an embodiment of the present invention provides lightning rod flange design method and terminal device, to solve existing skill
The problem of structure of lightning rod flange is designed not according to environmental factor in art.
The first aspect of the embodiment of the present invention provides a kind of lightning-arrest flange needle design method, including：
The relevant information for the lightning rod that collapses is obtained, analyzes the reason of lightning rod collapses；The relevant information includes lightning rod
Design information, material information, machining information and mount message；
According to the relevant information for the lightning rod that collapses, with AR autoregression technologies, based on Davenport spectrum analog fluctuating wind lotuses
It carries, while considers horizontal and vertical correlation, obtain the wind load time-history sample of various structure type lightning rods；
According to the wind load time-history sample of various structure type lightning rods, the stress performance of lightning rod flange, and root are analyzed
Lightning rod flange is optimized according to analysis result.
Optionally, the structure type of lightning rod includes：
It erects the single steel pipe lightning rod on framework A word columns, independent landing single steel pipe variable cross-section lightning rod, independent fall
The lightning rod of ground equilateral triangle steel pipe and angle steel lattice convolution.
Optionally, the wind load time-history sample according to various structure type lightning rods, analysis lightning rod flange by
Power performance, including：
ANSYS finite element solid modelings are carried out to lightning rod flange, analysis A words capital is connect with top single steel pipe lightning rod
Flange is under wind loads effect, the stress of lightning rod connecting flange and deformation.
Optionally, the analysis A words capital is kept away with top single steel pipe lightning rod connecting flange under wind loads effect
The stress of thunder needle connecting flange and deformation, including：
A words capital is analyzed with top single steel pipe lightning rod connecting flange under wind loads effect, lightning rod connection method
Blue flange bolt, the stress of flanged plate and stiffener and deformation.
Optionally, the analysis A words capital is kept away with top single steel pipe lightning rod connecting flange under wind loads effect
The stress of thunder needle connecting flange and deformation, further include：
A words capital is analyzed with top single steel pipe lightning rod connecting flange under wind loads effect, except the flange spiral shell
The stress of the other assemblies of lightning rod connecting flange except bolt, flanged plate and stiffener and deformation.
Optionally, the lightning rod flange is rigid flange, when the axial tension of rigid flange acts on：
In formula：The pulling force of a bolt for stress maximum, N are the pulling force suffered by flange, and n is spiral shell on ring flange
Bolt number,For bolt design ultimate bearing capacity；
When rigid flange tension or pressure or curved collective effect：
In formula：M is the moment of flexure suffered by flange；N is the pivotal role power suffered by flange；YiRotary shaft is arrived for bolt-center
Distance；Work as M/ | N | >=0.8r2When, take pipe outside diameter half 0.8 times is rotary shaft；Work as M/ | N |<0.8r2When, tube hub is taken as rotation
Shaft；Y is distance of the stress maximum bolt-center to rotary shaft；r2For outer wall of steel pipe radius.
Optionally, the design process of flange thickness is：
Evenly load on plateWherein Ly=min (1.8Ly1,2.2Ly2)；
Maximal bending moment in plate
Flange thickness
In formula：β is bending moment coefficients, and t is flange thickness, and f is design value for strength of material.
Optionally, when stiffener uses butt weld, plate thickness of putting more energy into is：
1) during vertical butt weld：
2) during horizontal butt weld：
When stiffener uses fillet weld, plate thickness of putting more energy into is：
In formula：P be the stiffener of bolt area lattice to the pressure that should bear,α is held for stiffener
Carry on a shoulder pole the ratio of counter-force, σfFor the tensile stress perpendicular to fusion length direction, τfFor the shear stress perpendicular to fusion length direction, B is
Stiffener width, for t to put more energy into plate thickness, e is P eccentricities, and h is stiffener height, S1For stiffener lower end corner cut height, S2For
Stiffener lower end transverse direction corner cut size,For butt weld shearing resistance, tensile strength design value, f is designed for steel strength
Value, fvFor steel shearing strength design value.
The second aspect of the embodiment of the present invention provides a kind of lightning rod flange design terminal device, including memory, place
Device is managed, the computer program that can be run on the processor is stored in the memory, the processor performs the meter
Following steps are realized during calculation machine program：
The relevant information for the lightning rod that collapses is obtained, analyzes the reason of lightning rod collapses；The relevant information includes lightning rod
Design information, material information, machining information and mount message；
According to the relevant information for the lightning rod that collapses, with AR autoregression technologies, based on Davenport spectrum analog fluctuating wind lotuses
It carries, while considers horizontal and vertical correlation, obtain the wind load time-history sample of various structure type lightning rods；
According to the wind load time-history sample of various structure type lightning rods, the stress performance of lightning rod flange, and root are analyzed
Lightning rod flange is optimized according to analysis result.
The third aspect of the embodiment of the present invention provides a kind of computer readable storage medium, the computer-readable storage
Media storage has computer program, is realized when the computer program is executed by processor as above-mentioned any lightning rod flange is set
The step of meter method.
Existing advantageous effect is the embodiment of the present invention compared with prior art：The embodiment of the present invention, acquisition are collapsed lightning-arrest
The relevant information of needle is to analyze the reason of lightning rod collapses, according to the relevant information for the lightning rod that collapses, with AR autoregression technologies,
Based on Davenport spectrum analog wind loads, while consider horizontal and vertical correlation, obtain various structure type lightning rods
Wind load time-history sample, further according to the wind load time-history sample of various structure type lightning rods, analysis lightning rod flange by
Power performance, and lightning rod flange is optimized according to analysis result, so as to be optimized to lightning rod flange, promotion is kept away
The wind resistance of thunder needle ensures the safe operation of lightning rod.
Description of the drawings
It to describe the technical solutions in the embodiments of the present invention more clearly, below will be to embodiment or description of the prior art
Needed in attached drawing be briefly described, it should be apparent that, the accompanying drawings in the following description be only the present invention some
Embodiment, for those of ordinary skill in the art, without having to pay creative labor, can also be according to these
Attached drawing obtains other attached drawings.
Fig. 1 is the flow chart of lightning rod flange design method provided in an embodiment of the present invention；
Fig. 2 is bolt strained schematic diagram one provided in an embodiment of the present invention；
Fig. 3 is bolt strained schematic diagram two provided in an embodiment of the present invention；
Fig. 4 is ring flange stress diagram provided in an embodiment of the present invention；
Fig. 5 is stiffener THICKNESS CALCULATION schematic diagram provided in an embodiment of the present invention；
Fig. 6 is osculating element schematic diagram in flange model provided in an embodiment of the present invention；
Fig. 7 is axle power FZ suffered by flange provided in an embodiment of the present invention and the time-history curves of moment M X, MY；
Fig. 8 is the stress time-history curves of bolt stress maximum point provided in an embodiment of the present invention；
Fig. 9 is the maximum bolt axial force curve graph after bolt provided in an embodiment of the present invention fails one by one；
Figure 10 is the maximum ring flange Z-direction deformation curve figure after bolt provided in an embodiment of the present invention fails one by one；
Figure 11 is the running environment schematic diagram of lightning rod flange design program provided in an embodiment of the present invention；
Figure 12 is the Program modual graph of lightning rod flange design program provided in an embodiment of the present invention.
Specific embodiment
In being described below, in order to illustrate rather than in order to limit, it is proposed that such as tool of particular system structure, technology etc
Body details, to understand thoroughly the embodiment of the present invention.However, it will be clear to one skilled in the art that there is no these specifically
The present invention can also be realized in the other embodiments of details.In other situations, it omits to well-known system, device, electricity
Road and the detailed description of method, in case unnecessary details interferes description of the invention.
In order to illustrate technical solutions according to the invention, illustrated below by specific embodiment.
Embodiment one
Fig. 1 shows the realization flow for the lightning rod flange design method that the embodiment of the present invention one provides, and details are as follows：
The reason of step S101 obtains the relevant information for the lightning rod that collapses, and analysis lightning rod collapses；The relevant information packet
Include design information, material information, machining information and the mount message of lightning rod.
Wherein, the structure type of lightning rod includes：Erect single steel pipe lightning rod on framework A word columns, independent landing
The lightning rod of single steel pipe variable cross-section lightning rod, independent landing equilateral triangle steel pipe and angle steel lattice convolution.
Design information, material information, machining information and the mount message of lightning rod are likely to lead to collapsing for lightning rod,
According to the relevant information for the lightning rod that collapses got, the exact cause that lightning rod collapses further is analyzed.
According to the relevant information for the lightning rod that collapses, with AR autoregression technologies, mould is composed based on Davenport by step S102
Intend wind loads, while consider horizontal and vertical correlation, obtain the wind load time-history sample of various structure type lightning rods.
Step S103 according to the wind load time-history sample of various structure type lightning rods, analyzes the stress of lightning rod flange
Performance, and lightning rod flange is optimized according to analysis result.
Optionally, the wind load time-history sample according to various structure type lightning rods, analysis lightning rod flange by
Power performance, including：
ANSYS finite element solid modelings are carried out to lightning rod flange, analysis A words capital is connect with top single steel pipe lightning rod
Flange is under wind loads effect, the stress of lightning rod connecting flange and deformation.
Specifically, the analysis A words capital and top single steel pipe lightning rod connecting flange are kept away under wind loads effect
The stress of thunder needle connecting flange and deformation, including：
A words capital is analyzed with top single steel pipe lightning rod connecting flange under wind loads effect, lightning rod connection method
Blue flange bolt, the stress of flanged plate and stiffener and deformation.
In addition, the analysis A words capital and top single steel pipe lightning rod connecting flange are taken shelter from the thunder under wind loads effect
The stress of needle connecting flange and deformation, further include：
A words capital is analyzed with top single steel pipe lightning rod connecting flange under wind loads effect, except flange bolt, method
The stress of the other assemblies of lightning rod connecting flange except blue plate and stiffener and deformation.
To ensure the rigidity of lightning rod, flange generally uses rigid flange.Rigid flange can be set by following theory
Meter.
During the axial tension effect of rigid flange：
In formula：The pulling force of a bolt for stress maximum, unit is newton；N is the pulling force suffered by flange, single
Position is newton；N is number of bolts on ring flange；For bolt design ultimate bearing capacity.
When rigid flange tension or pressure or curved collective effect：
In formula：Moments of flexure of the M suffered by flange, unit Nmm；N is the pivotal role power suffered by flange, and unit is ox
；YiFor the distance of bolt-center to rotary shaft, unit is millimeter；Work as M/ | N | >=0.8r2When, YiTake the 0.8 of pipe outside diameter half
It is again rotary shaft, referring to Fig. 2；Work as M/ | N |<0.8r2When, YiTube hub is taken as rotary shaft, referring to Fig. 3；Y is stress maximum bolt
To the distance of rotary shaft, unit is millimeter at center；r2For outer wall of steel pipe radius, unit is millimeter.
For flange thickness, ring flange is designed by pulling force operating conditions, and stress sketch can be determined according to three side support plates,
Boundary condition is clamped, free on one side for three sides, as shown in Figure 4.
Evenly load on plateWherein Ly=min (1.8Ly1,2.2Ly2)；
Maximal bending moment M in platemax=β qLx 2；
Flange thickness
In formula：β is bending moment coefficients, according to Ly/LxIt looks into certainly《Building structure Static Calculation handbook》；T is flange thickness, single
Position is millimeter；F is design value for strength of material, unit MPa.
Referring to Fig. 5, for plate thickness of putting more energy into, when stiffener uses butt weld, plate thickness of putting more energy into is：
1) during vertical butt weld：
2) during horizontal butt weld：
When stiffener uses fillet weld, plate thickness of putting more energy into is：
In formula：P be the stiffener of bolt area lattice to the pressure that should bear,α is held for stiffener
Carry on a shoulder pole the ratio of counter-force；σfFor the tensile stress perpendicular to fusion length direction, unit MPa；τfFor perpendicular to fusion length direction
Shear stress, unit MPa；B is stiffener width, and unit is millimeter；T is plate thickness of putting more energy into, and unit is millimeter；E is eccentric for P
Away from unit is millimeter；H is stiffener height, and unit is millimeter；S1For stiffener lower end corner cut height, unit is millimeter；S2For
Stiffener lower end transverse direction corner cut size, unit is millimeter；For butt weld shearing resistance, tensile strength design value, unit is
MPa；F be steel strength design value, unit MPa；fvFor steel shearing strength design value, unit MPa.
In order to study stress performance of the flange under wind loads, FEM calculation is carried out using ANSYS.It first should be true
Surely applicable finite element model.
The material of model is steel, and according to elastic plastic theory, material property model uses bilinearity etc. to reinforcing
Model B ISO.Elastic modulus E=2.06 × 10 of steel5MPa, Poisson's ratio μ=0.3, yield strength according to the trade mark of steel and
It is fixed.
From the point of view of previous correlative study, for steel pipe, ring flange and stiffener plate, available cell type has reality
Body unit and shell unit；For bolt, solid element, bar unit common are.Wherein, in the rational premise of mesh generation
Under, each component using solid element simulation flange is the most accurate.Therefore, which uses solid element
To flange, each component models SOLID185.It should be noted that occur " shear looking " or sytem matrix morbid state shadow in order to prevent
Computational accuracy is rung, the size in three directions of solid element should approach as possible during grid division.
There are three kinds of contact types in flange model：Contact A, nut and contact B, the spiral shell between ring flange between ring flange
Contact C between bar and screw hole.Referring to Fig. 6, these three contacts belong to surface-to-surface contact, correspondent entity cell S OLID185, contact
To object element and osculating element TARGE170 and CONTA173 is respectively adopted.
In specified target face and contact surface, it then follows " small convex close soft height is contact surface " principle, material are weaker for contact
Face, stronger material is target face.Since the rigidity of bolt is big compared with ring flange, and material is stronger, chooses ring flange as contact
Face, bolt are target face, and ring flange can be invaded by actually appearing bolt, and ring flange can only adapt to invade and deform.
Apply the pretightning force of bolt by preload unit PRETS179, it is as follows to apply process：1) pass through PSMESH orders
Preload unit is established on pitch section；2) the preload load specified by SLOAD orders application.Only by preload masterpiece
Under, understand that bolt-center section is applied with pretightning force according to analog result, and nut is with ring flange contact surface that there are phase negative sides
To contact force.
Since flange is simultaneously by axle power and Moment, when modeling, establishes the model of entire flange.
Flange base is connected with A words capital, and rigidity is very big, it is believed that just connects, therefore steel pipe to flange base and adds
Strength plate node applies rigid constraint.
Apply axle power and moment load in flange top steel pipe top face, according to Saint Venant's principle, enable flange upper steel pipe range
It spends for 1 times of diameter of steel tube.Concentrated force is applied to each node of steel pipe top surface, to realize axial uniformly stressed effect.Moment of flexure
Application process is as follows：(1) a MASS21 unit is established at steel pipe end face center, enables it that there is the degree of freedom in 6 directions
Uxyz and ROTxyz；(2) each node of the MASS cell nodes and steel pipe top surface is chosen, rigid face is established by CERIG orders, is protected
Demonstrate,prove the transmission of moment of flexure；(3) concentrated bending moment is applied to MASS units.
In order to more preferably analyze the stress performance of flange, wind loads time-history analysis is carried out.From the model of entire framework
Extraction obtains the axle power of flange and moment of flexure time-history curves, imports the flange model and carries out time-histories calculating.Axle power FZ suffered by flange
It is as shown in Figure 7 with the time-history curves of moment M X, MY.
In view of finite element model node and unit number are more, to take into account computational efficiency and computational accuracy, the lotus of 0~60s is taken
It is loaded into row time-history analysis, a length of 0.1s of analysis step.
Take close on loading at the end of stress it is larger load step time=52.9 illustrate.It can know the law according to analog result
The blue universal stress of disk is smaller, and maximum stress 155MPa, stress larger part is distributed in around bolt hole, ring flange edge stress
Very little.Maximum stress is 266MPa on stiffener, appears in the stress raiser that stiffener has a common boundary with steel pipe, and stiffener is big absolutely
The stress of subregion is no more than 90MPa.Bolt is axle power tension state, and maximum bolt stress is 279MPa, less than spiral shell
Bolt allowable stress.Bolt stress is consistent with ring flange stress distribution trend.Steel pipe maximum stress is 100MPa, positioned at steel pipe with adding
Strength plate intersection, entire steel pipe stress is in elastic range.
Flange distortion at the end of loading is as shown below, and ring flange is in bending deformation feature, ring flange Z-direction maximum displacement
For 0.037mm, Z-direction least displacement is -0.024mm, and compared to flange diameter, flange base gradient about 1/8700, shows at this time
The contribution very little that flange distortion deforms lightning rod.
Lightning rod is substantially swung for a long time under the action of the wind, and bolt stress constantly changes, and causes part bolt that fatigue occurs
Damage, therefore analysis of fatigue is carried out to the bolt at where maximum stress.It is obtained according to simulation, the stress time-histories of stress maximum point
Curve is as shown in Figure 8.Wherein, the maximum stress of the point is 394.1MPa, minimum stress 260.4MPa, and bolt stress width is
133.7MPa。
At present, China's Code for design of steel structures lacks relevant design discipline for the fatigue design that bolt tension connects.
In the world, German Specification VDI-2230 is more mature about the calculating of bolt fatigue, can provide reference for analysis.In VDI-2230
The alternating stress amplitude of bolt fatigue limit can be calculated as the following formula：
σASV=0.85 (150/d+45)
It is computed, for finite element example, corresponding stress-number of cycles N=2 × 106Bolt stress width feasible value be
86.0MPa.Bolt stress width is more than allowable stress width, and with fatigue damage, add up will be cracked in use, most
Lead to fatigue rupture eventually.
From another point of view, the value of bolt pretightening is also most important.Pretightning force is bigger, and bolt alternate stress is with regard to smaller, spiral shell
Bolt stress amplitude is also just smaller.Appropriate increase bolt pretightening can not only improve the locking kinetic force of bolt, moreover it is possible to improve bolt
Fatigue life.Therefore, it is suggested that bolt pretightening takes large values as far as possible in the reasonable scope.
In addition, VDI-2230 is pointed out, the bolt rolled later is heat-treated, due to introducing residual compressive stress, tired pole
The bolt that limit for height rolls before in heat treatment, can reach original 1.7 times.Therefore, in the processing technology of bolt, it is proposed that
The bolt rolled later using heat treatment.
When having part bolt because after fatigue or other reasons failure, remaining bolt stress increases due to redistribution, with
For typical duty load FZ=32kN, M=283kNm, the stress of remaining bolt after bolt fails one by one is calculated, result of calculation is such as
Shown in the following table 1.
The result of calculation that 1 bolt of table fails one by one
| Fail bolt number | Maximum bolt axial force (kN) | Bolt tensile capacity (kN) |
| 0 | 78 | 184 |
| 2 | 107 | 184 |
| 4 | 156 | 184 |
| 6 | 246 | 184 |
When 1 bolt failure, under typical duty load, steel pipe maximum stress be 248MPa, stress maximum bolt location
The ring flange of lattice is still in elastic stage, and only stress is up to 341MPa at screw hole ambient stress concentration, the stiffener of area's lattice
330MPa is respectively less than with ring flange intersection stress.Bolt maximum stress is 544MPa, positioned at stress raisers point, the bolt
Pulling force is 149.9kN, is less than bolt yield strength, and bolt not yet destroys.At this point, ring flange maximum Z-direction is deformed into 0.54mm,
Ring flange tilts about 1/856.
When 2 bolt failures, under typical duty load, steel pipe maximum stress be 248MPa, stress maximum bolt location
The ring flange majority of lattice is still in elastic stage, and only stress is up to 414MPa at screw hole ambient stress concentration, which adds
Strength plate is respectively less than 330MPa with ring flange intersection stress.Bolt maximum stress is 655MPa, should positioned at stress raisers point
Bolt tension force is 179.6kN, is less than but very close to bolt bearing capacity, bolt will destroy.At this point, ring flange maximum Z-direction becomes
Shape is 0.91mm, and ring flange tilts about 1/530.
When 3 bolt failures, under typical duty load, steel pipe maximum stress be 337MPa, stress maximum bolt location
The ring flange of lattice is mostly in elastic stage, and stress is up to 425MPa at screw hole ambient stress concentration, locally initially enters
Plasticity.The stiffener of area's lattice is more than 296MPa with ring flange intersection stress, and has part to enter plasticity.Bolt maximum stress
For 648MPa, the larger face stress of stress is generally more than 577MPa on screw rod, which is 202.5kN, more than bolt
Tensile capacity, it is believed that bolt has destroyed at this time.At this point, ring flange maximum Z-direction is deformed into 1.31mm, ring flange tilts about
1/371。
When 5 bolt failures, under typical duty load, steel pipe maximum stress be 363MPa, stress maximum bolt location
The flange disk stress of lattice is more than largely 293MPa, and plasticity, stiffener and the ring flange boundary of area's lattice are entered around screw hole
Place's stress is all higher than 330MPa.Bolt maximum stress alreadys exceed 600MPa, and stress raisers point is even up to 673MPa, surpasses
Bolt yield strength is crossed, which is 273.3kN, it is believed that bolt has destroyed at this time.At this point, ring flange maximum Z-direction
2.55mm is deformed into, ring flange tilts about 1/195, and lightning rod deformation is notable.
Comprehensive analysis more than finite element and manual calculation result, bolt is successively under failure conditions, and the development of bolt maximum axle power is such as
Shown in figure.By Fig. 9 and Figure 10 it is found that as bolt failure number increases, bolt maximum axle power quickly increases.Identical failure bolt
Under, finite element result is about bigger 50kN than manual calculation result, this is because the presence of pretightning force, flange rotary axis that hand computation uses with it is true
There are deviations for truth condition, cause manual calculation result bolt axial force less than normal.From the point of view of the trend of bolt axial force development, until 3 bolts
During failure, other bolts of flange just start to surrender, and flange joint destroys.This shows that flange has larger static(al) nargin,
It can be to find that accident potential provides the time in advance.
Meanwhile as bolt fails one by one, ring flange Z-direction deforms also linear growth trend, for position at the top of lightning rod
Shifting is monitored, and can find flange abnormal deformation in time, early warning is provided for accident.
In view of the brittle fracture under low temperature problem that steel are likely to occur, situation about failing may also occur in the stiffener of flange.Work as institute
When some stiffeners fail, script rigid flange is just changed into the pattern of flexible flange.For the feelings of all stiffeners failure
Condition with typical duty load FZ=32kN, for M=283kNm, carries out FEM calculation, result of calculation is as follows.
When there is 1 piece of stiffener failure, under typical duty load, steel pipe maximum stress is 253MPa, appears in steel pipe and method
Blue disk intersection.The flange disk stress of stress maximum bolt location lattice is largely no more than 204MPa, due to should around screw hole
Power concentrated stress is larger, is up to 305MPa, is surrender.Bolt maximum stress is 473MPa, is less than bolt yield strength,
The bolt tension force is 133.4kN, and about 8kN is increased when not destroyed compared to stiffener.At this point, ring flange maximum Z-direction is deformed into
0.31mm, ring flange tilt about 1/1357.Therefore, the consequence of stiffener failure is safer compared to bolt failure.
When all stiffeners fail, under typical duty load, steel pipe maximum stress is 390MPa, appears in steel pipe and flange
Disk intersection.The flange disk stress of stress maximum bolt location lattice is largely no more than 322MPa, due to stress around screw hole
Concentrated stress is larger, is up to 413MPa.Bolt maximum stress is 652MPa, and more than bolt yield strength, which is
208.1kN, it is believed that bolt has destroyed at this time.At this point, ring flange maximum Z-direction is deformed into 0.81mm, ring flange tilts about 1/
490。
It is understood based on above-mentioned analysis：
1. finite element model simulates stressing conditions of the entire lightning rod flange under wind loads, as a result more accurate
It is credible.
2. stress of each component of flange under wind loads is in elastic range, and there are larger nargin.
3. Fatigue Stress Amplitude of the bolt under wind loads is 133.7MPa, the limit value allowed more than VDI-2230
The main reason for 86MPa, fatigue rupture is bolt fracture.
4. bolt fails one by one, until after the 3rd bolt failure, maximum bolt power is more than its tensile capacity, flange
It destroys.
5. stiffener fails, consequence is serious not as good as bolt failure, therefore, should more pay attention to the safeguard measure of bolt.
6. to avoid similar incidents, the measure that can be taken has：
1) flange and bolt material requirement are improved, selects D grades of steel；
2) bolt processing technic featuring is improved, the bolt that heat treatment is selected to roll before；
3) strengthening stud ensures bolt nargin, reduces bolt stress, covert to reduce bolt stress width；
4) increase bolt pretightening in the reasonable scope, bolt stress width can be reduced；
5) ensure the flatness of ring flange contact surface, reduce the lightning rod caused due to gap and swing.
Above-mentioned lightning rod flange design method obtains the relevant information for the lightning rod that collapses to analyze the original that lightning rod collapses
Cause, according to the relevant information for the lightning rod that collapses, with AR autoregression technologies, based on Davenport spectrum analog wind loads, together
When consider horizontal and vertical correlation, the wind load time-history sample of various structure type lightning rods is obtained, further according to various structures
The wind load time-history sample of type lightning rod analyzes the stress performance of lightning rod flange, and according to analysis result to the skill of handling needles of taking shelter from the thunder
Orchid optimizes, and so as to be optimized to lightning rod flange, promotes the wind resistance of lightning rod, ensures the safety of lightning rod
Operation.
It should be understood that the size of the serial number of each step is not meant to the priority of execution sequence, each process in above-described embodiment
Execution sequence should determine that the implementation process without coping with the embodiment of the present invention forms any limit with its function and internal logic
It is fixed.
Embodiment two
Corresponding to the lightning rod flange design method described in foregoing embodiments, Figure 11 shows provided in an embodiment of the present invention
The running environment schematic diagram of lightning rod flange design program.For convenience of description, part related to the present embodiment is illustrated only.
In the present embodiment, the lightning rod flange design program 200 is installed and is run in terminal device 20.The end
End equipment 20 may include, but be not limited only to, memory 201 and processor 202.Figure 11 is illustrated only with component 201-202's
Terminal device 20, it should be understood that be not required for implementing all components shown, the implementation that can be substituted is more or more
Few component.
The memory 201 can be the internal storage unit of the terminal device 20 in some embodiments, such as should
The hard disk or memory of terminal device 20.The memory 201 can also be the terminal device 20 in further embodiments
The plug-in type hard disk being equipped on External memory equipment, such as the terminal device 20, intelligent memory card (Smart Media
Card, SMC), secure digital (Secure Digital, SD) card, flash card (Flash Card) etc..Further, it is described to deposit
Reservoir 201 can also both include the internal storage unit of the terminal device 20 or including External memory equipment.The memory
201 are installed on the application software and Various types of data of the terminal device 20, such as the accelerated life test sample for storing
Program code of distribution program 200 etc..The memory 201, which can be also used for temporarily storing, have been exported or will export
Data.
The processor 202 can be a central processing unit (Central Processing in some embodiments
Unit, CPU), microprocessor or other data processing chips, for run the program code that is stored in the memory 201 or
Data are handled, such as perform described lightning rod flange design program 200 etc..
The terminal device 20 may also include display, and the display can be light-emitting diode display, liquid in some embodiments
Crystal display, touch-control liquid crystal display and OLED (Organic Light-Emitting Diode, organic light-emitting diodes
Pipe) touch device etc..
2 are please referred to Fig.1, is the Program modual graph of lightning rod flange design program 200 provided in an embodiment of the present invention.At this
In embodiment, the lightning rod flange design program 200 can be divided into one or more modules, one or more
A module is stored in the memory 201, and by one or more processors (the present embodiment is the processor 202) institute
It performs, to complete the present invention.For example, in fig. 12, the lightning rod flange design program 200 can be divided into information and obtain
Modulus block 301, processing module 302 and optimization design module 303.The so-called module of the present invention refers to complete specific function
Series of computation machine program instruction section, than program more suitable for describing the lightning rod flange design program 200 in the terminal
Implementation procedure in equipment 20.The function of specifically introducing the module 301-303 is described below.
Wherein, data obtaining module 301, for obtaining the relevant information for the lightning rod that collapses, the original that analysis lightning rod collapses
Cause；The relevant information includes design information, material information, machining information and the mount message of lightning rod.
Processing module 302 for the relevant information according to the lightning rod that collapses, with AR autoregression technologies, is based on
Davenport spectrum analog wind loads, while consider horizontal and vertical correlation, obtain the wind of various structure type lightning rods
Load time-histories sample.
Optimization design module 303 for the wind load time-history sample according to various structure type lightning rods, analyzes lightning rod
The stress performance of flange, and lightning rod flange is optimized according to analysis result.
Optionally, the structure type of lightning rod includes：
It erects the single steel pipe lightning rod on framework A word columns, independent landing single steel pipe variable cross-section lightning rod, independent fall
The lightning rod of ground equilateral triangle steel pipe and angle steel lattice convolution.
Optionally, processing module 302 is used for：ANSYS finite element solid modelings are carried out to lightning rod flange, analyze A word columns
Top and top single steel pipe lightning rod connecting flange are under wind loads effect, the stress of lightning rod connecting flange and deformation.
Optionally, processing module 302 is specifically used for：
A words capital is analyzed with top single steel pipe lightning rod connecting flange under wind loads effect, lightning rod connection method
Blue flange bolt, the stress of flanged plate and stiffener and deformation.
As a kind of embodiment, the lightning rod flange is rigid flange, when the axial tension of rigid flange acts on：
In formula：The pulling force of a bolt for stress maximum, N are the pulling force suffered by flange, and n is spiral shell on ring flange
Bolt number,For bolt design ultimate bearing capacity；
When rigid flange tension or pressure or curved collective effect：
In formula：M is the moment of flexure suffered by flange；N is the pivotal role power suffered by flange；YiRotary shaft is arrived for bolt-center
Distance；Work as M/ | N | >=0.8r2When, take pipe outside diameter half 0.8 times is rotary shaft；Work as M/ | N |<0.8r2When, tube hub is taken as rotation
Shaft；Y is distance of the stress maximum bolt-center to rotary shaft；r2For outer wall of steel pipe radius.
As another embodiment, the design process of flange thickness is：
Evenly load on plateWherein Ly=min (1.8Ly1,2.2Ly2)；
Maximal bending moment M in platemax=β qLx 2；
Flange thickness
In formula：β is bending moment coefficients, and t is flange thickness, and f is design value for strength of material.
As a kind of embodiment, when stiffener uses butt weld, plate thickness of putting more energy into is：
1) during vertical butt weld：
2) during horizontal butt weld：
When stiffener uses fillet weld, plate thickness of putting more energy into is：
In formula：P be the stiffener of bolt area lattice to the pressure that should bear,α is held for stiffener
Carry on a shoulder pole the ratio of counter-force, σfFor the tensile stress perpendicular to fusion length direction, τfFor the shear stress perpendicular to fusion length direction, B is
Stiffener width, for t to put more energy into plate thickness, e is P eccentricities, and h is stiffener height, S1For stiffener lower end corner cut height, S2For
Stiffener lower end transverse direction corner cut size,For butt weld shearing resistance, tensile strength design value, f is designed for steel strength
Value, fvFor steel shearing strength design value.
It is apparent to those skilled in the art that for convenience of description and succinctly, only with above-mentioned each work(
Can unit, module division progress for example, in practical application, can be as needed and by above-mentioned function distribution by different
Functional unit, module are completed, i.e., the internal structure of described device are divided into different functional units or module, more than completion
The all or part of function of description.Each functional unit, module in embodiment can be integrated in a processing unit, also may be used
To be that each unit is individually physically present, can also two or more units integrate in a unit, it is above-mentioned integrated
The form that hardware had both may be used in unit is realized, can also be realized in the form of SFU software functional unit.In addition, each function list
Member, the specific name of module are not limited to the protection domain of the application also only to facilitate mutually distinguish.Above system
The specific work process of middle unit, module can refer to the corresponding process in preceding method embodiment, and details are not described herein.
In the above-described embodiments, it all emphasizes particularly on different fields to the description of each embodiment, is not described in detail or remembers in some embodiment
The part of load may refer to the associated description of other embodiments.
Those of ordinary skill in the art may realize that each exemplary lists described with reference to the embodiments described herein
Member and algorithm steps can be realized with the combination of electronic hardware or computer software and electronic hardware.These functions are actually
It is performed with hardware or software mode, specific application and design constraint depending on technical solution.Professional technician
Described function can be realized using distinct methods to each specific application, but this realization is it is not considered that exceed
The scope of the present invention.
In embodiment provided by the present invention, it should be understood that disclosed device/terminal device and method, it can be with
It realizes by another way.For example, device described above/terminal device embodiment is only schematical, for example, institute
The division of module or unit is stated, only a kind of division of logic function can have other dividing mode in actual implementation, such as
Multiple units or component may be combined or can be integrated into another system or some features can be ignored or does not perform.Separately
A bit, shown or discussed mutual coupling or direct-coupling or communication connection can be by some interfaces, device
Or the INDIRECT COUPLING of unit or communication connection, can be electrical, machinery or other forms.
The unit illustrated as separating component may or may not be physically separate, be shown as unit
The component shown may or may not be physical unit, you can be located at a place or can also be distributed to multiple
In network element.Some or all of unit therein can be selected according to the actual needs to realize the mesh of this embodiment scheme
's.
In addition, each functional unit in each embodiment of the present invention can be integrated in a processing unit, it can also
That each unit is individually physically present, can also two or more units integrate in a unit.Above-mentioned integrated list
The form that hardware had both may be used in member is realized, can also be realized in the form of SFU software functional unit.
If the integrated module/unit realized in the form of SFU software functional unit and be independent product sale or
In use, it can be stored in a computer read/write memory medium.Based on such understanding, the present invention realizes above-mentioned implementation
All or part of flow in example method, can also instruct relevant hardware to complete, the meter by computer program
Calculation machine program can be stored in a computer readable storage medium, the computer program when being executed by processor, it can be achieved that on
The step of stating each embodiment of the method.Wherein, the computer program includes computer program code, the computer program generation
Code can be source code form, object identification code form, executable file or certain intermediate forms etc..The computer-readable medium
It can include：Any entity of the computer program code or device, recording medium, USB flash disk, mobile hard disk, magnetic can be carried
Dish, CD, computer storage, read-only memory (ROM, Read-Only Memory), random access memory (RAM,
Random Access Memory), electric carrier signal, telecommunication signal and software distribution medium etc..It is it should be noted that described
The content that computer-readable medium includes can carry out appropriate increasing according to legislation in jurisdiction and the requirement of patent practice
Subtract, such as in certain jurisdictions, according to legislation and patent practice, computer-readable medium does not include electric carrier signal and electricity
Believe signal.
Embodiment described above is merely illustrative of the technical solution of the present invention, rather than its limitations；Although with reference to aforementioned reality
Example is applied the present invention is described in detail, it will be understood by those of ordinary skill in the art that：It still can be to aforementioned each
Technical solution recorded in embodiment modifies or carries out equivalent replacement to which part technical characteristic；And these are changed
Or replace, the spirit and scope for various embodiments of the present invention technical solution that it does not separate the essence of the corresponding technical solution should all
It is included within protection scope of the present invention.
Claims (10)
- A kind of 1. lightning rod flange design method, which is characterized in that including：The relevant information for the lightning rod that collapses is obtained, analyzes the reason of lightning rod collapses；The relevant information includes setting for lightning rod Count information, material information, machining information and mount message；According to the relevant information for the lightning rod that collapses, with AR autoregression technologies, based on Davenport spectrum analog wind loads, Horizontal and vertical correlation is considered simultaneously, obtains the wind load time-history sample of various structure type lightning rods；According to the wind load time-history sample of various structure type lightning rods, analyze the stress performance of lightning rod flange, and according to point Analysis result optimizes lightning rod flange.
- 2. lightning rod flange design method as described in claim 1, which is characterized in that the structure type of lightning rod includes：Erect the single steel pipe lightning rod on framework A word columns, independent landing single steel pipe variable cross-section lightning rod, independent landing etc. The lightning rod of side triangle steel pipe and angle steel lattice convolution.
- 3. lightning rod flange design method as claimed in claim 2, which is characterized in that described to be taken shelter from the thunder according to various structure types The wind load time-history sample of needle analyzes the stress performance of lightning rod flange, including：ANSYS finite element solid modelings, analysis A words capital and top single steel pipe lightning rod connecting flange are carried out to lightning rod flange Under wind loads effect, the stress of lightning rod connecting flange and deformation.
- 4. lightning rod flange design method as claimed in claim 3, which is characterized in that the analysis A words capital and top are single Steel pipe lightning rod connecting flange is under wind loads effect, the stress of lightning rod connecting flange and deformation, including：A words capital is analyzed with top single steel pipe lightning rod connecting flange under wind loads effect, lightning rod connecting flange Flange bolt, the stress of flanged plate and stiffener and deformation.
- 5. lightning rod flange design method as claimed in claim 4, which is characterized in that the lightning rod flange is stiffness method Orchid, when the axial tension of rigid flange acts on：In formula：The pulling force of a bolt for stress maximum, N are the pulling force suffered by flange, and n is Number of Bolts on ring flange Mesh,For bolt design ultimate bearing capacity；When rigid flange tension or pressure or curved collective effect：In formula：M is the moment of flexure suffered by flange；N is the pivotal role power suffered by flange；YiDistance for bolt-center to rotary shaft； Work as M/ | N | >=0.8r2When, take pipe outside diameter half 0.8 times is rotary shaft；Work as M/ | N |<0.8r2When, it is rotary shaft to take tube hub； Y is distance of the stress maximum bolt-center to rotary shaft；r2For outer wall of steel pipe radius.
- 6. lightning rod flange design method as claimed in claim 5, which is characterized in that the design process of flange thickness is：Evenly load on plateWherein Ly=min (1.8Ly1,2.2Ly2)；Maximal bending moment M in platemax=β qLx 2；Flange thicknessIn formula：β is bending moment coefficients, and t is flange thickness, and f is design value for strength of material.
- 7. lightning rod flange design method as claimed in claim 6, which is characterized in that when stiffener uses butt weld, add Strength plate thickness is：1) during vertical butt weld：2) during horizontal butt weld：When stiffener uses fillet weld, plate thickness of putting more energy into is：In formula：P be the stiffener of bolt area lattice to the pressure that should bear,α undertakes instead for stiffener The ratio of power, σfFor the tensile stress perpendicular to fusion length direction, τfFor the shear stress perpendicular to fusion length direction, B is puts more energy into Plate width, for t to put more energy into plate thickness, e is P eccentricities, and h is stiffener height, S1For stiffener lower end corner cut height, S2To put more energy into Plate lower end transverse direction corner cut size,ft WFor butt weld shearing resistance, tensile strength design value, f is steel strength design value, fvFor Steel shearing strength design value.
- 8. a kind of lightning rod flange design device, which is characterized in that including：Data obtaining module for obtaining the relevant information for the lightning rod that collapses, analyzes the reason of lightning rod collapses；The related letter Breath includes design information, material information, machining information and the mount message of lightning rod.For the relevant information according to the lightning rod that collapses, with AR autoregression technologies, mould is composed based on Davenport for processing module Intend wind loads, while consider horizontal and vertical correlation, obtain the wind load time-history sample of various structure type lightning rods.Optimization design module for the wind load time-history sample according to various structure type lightning rods, analyzes lightning rod flange Stress performance, and lightning rod flange is optimized according to analysis result.
- 9. a kind of lightning rod flange design terminal device, which is characterized in that including memory, processor, deposited in the memory The computer program that can be run on the processor is contained, the processor realizes following step when performing the computer program Suddenly：The relevant information for the lightning rod that collapses is obtained, analyzes the reason of lightning rod collapses；The relevant information includes setting for lightning rod Count information, material information, machining information and mount message；According to the relevant information for the lightning rod that collapses, with AR autoregression technologies, based on Davenport spectrum analog wind loads, Horizontal and vertical correlation is considered simultaneously, obtains the wind load time-history sample of various structure type lightning rods；According to the wind load time-history sample of various structure type lightning rods, analyze the stress performance of lightning rod flange, and according to point Analysis result optimizes lightning rod flange.
- 10. a kind of computer readable storage medium, the computer-readable recording medium storage has computer program, and feature exists In when the computer program is executed by processor the step of realization such as any one of claim 1 to 8 the method.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711445094.3A CN108228992A (en) | 2017-12-27 | 2017-12-27 | lightning rod flange design method and terminal device |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201711445094.3A CN108228992A (en) | 2017-12-27 | 2017-12-27 | lightning rod flange design method and terminal device |
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| CN115270430A (en) * | 2022-07-08 | 2022-11-01 | 中国舰船研究设计中心 | Design method of marine distributed inclined lightning rod |
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Application publication date: 20180629 |