Search result: GB 50463-2019 (GB 50463-2008 Older version)
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| GB 50463-2019 | English | RFQ |
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Code for design of vibration isolation
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GB 50463-2019
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| GB 50463-2008 | English | RFQ |
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Code for design of vibration isolation
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GB 50463-2008
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| Standard ID | GB 50463-2019 (GB50463-2019) | | Description (Translated English) | Code for design of vibration isolation | | Sector / Industry | National Standard | | Classification of Chinese Standard | P15 | | Classification of International Standard | 91.120.25 | | Word Count Estimation | 158,122 | | Date of Issue | 2019 | | Date of Implementation | 2020-06-01 |
GB 50463-2019 English name.Code for design of vibration isolation
1 General
1.0.1 In order to make the vibration isolation design of the project based on the characteristics of the vibration source and the vibration isolation object, rationally select the vibration isolation method, dynamic parameters, support structure form and vibration isolator, etc., to achieve advanced technology, economical and reasonable, and ensure normal use. To meet the requirements of production and environment, formulate this standard.
1.0.2 This standard applies to vibration isolation design in the following situations.
1 Active vibration isolation and intelligent vibration isolation to reduce the adverse effects of vibration generated by power machines, vehicles, etc. on production, work, life and the surrounding environment;
2.Passive vibration isolation and intelligent vibration isolation to reduce the adverse effects of external vibration on instruments, machines and equipment.
1.0.3 This standard is not suitable for isolating vibrations caused by natural actions such as earthquakes, winds, and waves.
1.0.4 In addition to implementing this standard, the vibration isolation design of the project should also comply with the current relevant national standards.
2 Terminology and symbols
2.1 Terminology
2.1.1 active vibration isolation active vibration isolation
Vibration isolation measures taken for vibration sources.
2.1.2 Passive vibration isolation passive vibration isolation
Vibration isolation measures for instruments, meters, machines and other equipment affected by vibration.
2.1.3 intelligent vibration isolation
There is an external control energy input, and the control parameters can be intelligently adjusted according to the control target.
2.1.4 barrier vibration isolation barrier vibration isolation
Barriers are installed in the vibration transmission path to reduce the impact of ground vibration transmission.
2.1.5 vibration isolation system vibration isolation system
A system consisting of a pedestal structure, vibration isolators and necessary dampers.
2.1.6 vibration isolated object vibration isolated object
Instruments, instruments, machines, etc. that require vibration isolation measures.
2.1.7 vibration isolation system vibration isolation institution
A system consisting of vibration isolation objects and vibration isolation systems.
2.1.8 allowable vibration value allowable vibration value
The maximum vibration limit value of the vibrated object.
2.1.9 Transmissibility
When the vibration system is forced to vibrate, the ratio of the displacement response amplitude to the external excitation displacement amplitude; for active vibration isolation, it is the ratio of the output displacement of the vibration isolation system to the static displacement of the system under the action of the disturbance amplitude; for passive vibration isolation, It is the ratio of the output displacement of the vibration isolation system to the input disturbance displacement.
2.1.10 vibration isolator vibration isolator
A device that isolates vibration or shock transmission, often in combination with a damper.
2.1.11 damper damper
A device that reduces shock or vibration by means of energy dissipation.
2.2 Symbols
2.2.1 Action and action effect.
Fx——disturbance force value acting on the center of mass of the vibration isolation system along the χ axis;
Fy——disturbance force acting on the center of mass of the vibration isolation system along the y-axis;
Fz——the disturbance force value acting on the center of mass of the vibration isolation system along the z-axis;
Mx——the disturbance moment value around the χ axis acting on the mass center of the vibration isolation system;
My——the disturbance moment value around the y-axis at the mass center of the vibration isolation system;
Mz——the disturbance moment value around the z-axis at the center of mass of the vibration isolation system;
u—vibration displacement;
υ——vibration velocity;
a—vibration acceleration;
ux—vibration displacement along the χ axis at the mass center of the vibration isolation system;
uy—vibration displacement along the y-axis at the mass center of the vibration isolation system;
uz—vibration displacement along the z-axis at the mass center of the vibration isolation system;
uφx——vibration angular displacement of the center of mass of the vibration isolation system rotating around the χ axis;
uφy——vibration angular displacement of the center of mass of the vibration isolation system rotating around the y-axis;
uφz—the vibration angular displacement of the center of mass of the vibration isolation system rotating around the z-axis;
uox—vibration displacement along the χ axis generated at the supporting structure or foundation;
uoy—vibration displacement along the y-axis generated at the supporting structure or foundation;
uoz—vibration displacement along the z-axis generated at the supporting structure or foundation;
uoφx—the vibration angular displacement generated at the supporting structure or foundation around the χ axis;
uoφy——vibration angular displacement generated at the supporting structure or foundation around the y-axis;
uoφz——the vibration angular displacement generated by the supporting structure or the foundation around the z-axis.
2.2.2 Calculation indicators.
Kx——total stiffness of the vibration isolator along the χ axis;
Ky—the total stiffness of the vibration isolator along the y-axis;
Kz——total stiffness of the vibration isolator along the z-axis;
Kφx—total torsional rigidity of the vibration isolator around the χ axis;
Kφy—total torsional rigidity of the vibration isolator around the y-axis;
Kφz—total torsional rigidity of the vibration isolator around the z-axis;
ω——interference circle frequency;
ωnx——the undamped natural circular frequency of the vibration isolation system along the χ axis;
ωny—the undamped natural circular frequency of the vibration isolation system along the y-axis;
ωnz—the undamped natural circular frequency of the vibration isolation system along the z-axis;
ωnφx——the undamped natural circular frequency of the vibration isolation system rotating around the χ axis;
ωnφy——the undamped natural circular frequency of the vibration isolation system rotating around the y-axis;
ωnφz—the undamped natural circular frequency of the vibration isolation system rotating around the z-axis;
ξ——damping ratio;
ξx——the damping ratio of the vibration isolator along the χ axis;
ξy——the damping ratio of the vibration isolator along the y-axis;
ξz——the damping ratio of the vibration isolator along the z-axis;
ξφx——the damping ratio of the vibration isolator rotating around the χ axis;
ξφy——the damping ratio of the vibration isolator rotating around the y-axis;
ξφz——the damping ratio of the vibration isolator rotating around the z-axis;
Es - the static elastic modulus of the vibration isolation material;
Ed——dynamic modulus of elasticity of the vibration-isolation material;
[u]——allowable vibration displacement;
[υ]——allowable vibration speed;
[a]——allowable vibration acceleration;
[τ]——allowable shear stress;
m - the total mass of the vibration isolation system;
f - the frequency of the vibration isolation system.
2.2.3 Geometric parameters.
Jx——the moment of inertia of the vibration isolation system around the χ axis;
Jy——the moment of inertia of the vibration isolation system around the y-axis;
Jz—the moment of inertia of the vibration isolation system around the z-axis.
3 basic rules
3.1 General provisions
3.1.1 The engineering vibration isolation design should have the following information.
1 The model, specification and outline size of the vibration isolation object;
2 The center of mass position, mass and moment of inertia of the vibration isolation object;
3 Dimensions of the base of the vibration isolation object, ancillary equipment, the position of the pipeline, the thickness of the grouting layer, the position of the anchor bolts and embedded parts;
4 Pipeline data connected with vibration isolation objects and foundation;
5 When the vibration isolator is supported on the floor or support, provide the design data of the supporting structure; when the vibration isolator is supported on the foundation, provide the engineering geological survey data, foundation dynamic parameters and relevant data of the adjacent foundation;
6 When the vibration is a periodic disturbance, provide the frequency, disturbance value, disturbance moment, position and direction of the action point; when the vibration is a random disturbance, provide the frequency spectrum, position and direction of the action point; When the vibration acts as an impact disturbance, provide the impact mass, impact velocity and interval time between two impacts, etc.;
7 The amplitude and frequency characteristics of the disturbance vibration at the support of the vibration isolation object;
8 Information on the ambient temperature of the vibration isolation object and the influence of corrosive media;
9 Permissible vibration standards for vibration isolation objects.
3.1.2 The selection of the vibration isolation design scheme should be determined after optimization and comparison of various schemes.
3.1.3 The selection of vibration isolation methods should meet the following requirements.
1 When supporting vibration isolation is adopted, as shown in Figure 3.1.3(a) and Figure 3.1.3(b), the vibration isolator should be installed under the base or pedestal structure of the vibration Horizontal vibration.
2 When suspension type vibration isolation is adopted, as shown in Figure 3.1.3(c) and Figure 3.1.3(d), the vibration isolation object should be placed Suspended on rigid suspenders hinged at both ends, it can be used to isolate horizontal vibration; when a vibration isolator is installed at the upper or lower end of the suspended suspender, it can be used to isolate vertical and horizontal vibrations, as shown in Figure 3.1.3(e) and Figure 3.1.3(f).
Figure 3.1.3 Vibration isolation method
1-vibration isolation object; 2-vibration isolator; 3-rigid suspender
3 When barrier vibration isolation is adopted, vibration isolation methods such as ditch barrier, row pile barrier, wave-resistance plate barrier and combined barrier can be used to isolate the propagation of near-surface site vibration.
3.1.4 The vibration response of the vibration isolation object after vibration isolation should not be greater than the current national standard "Construction Engineering Allowable Vibration Standard" GB 50868 and the allowable vibration value required by the equipment manufacturer, and the active vibration isolation fashion should meet the requirements of environmental vibration.
3.1.5 The bearing capacity of the vibration isolator should be checked, and the vibration load and internal force combination should meet the relevant provisions of the current national standard "Standard for Building Vibration Loads" GB/T 51228 and "Code for Building Structure Loads" GB 50009.
3.1.6 When the service life of the vibration isolation system is lower than the service life of the vibration isolation object, the vibration isolation system should be able to be replaced.
3.2 Vibration isolation system and parameters
3.2.1 The vibration isolation system should include vibration isolators, dampers, pedestal structures and vibration isolation objects, and the intelligent vibration isolation system should also include control systems and monitoring systems.
3.2.2 Vibration isolators and dampers should be determined after vibration isolation calculations, and their arrangement should meet the following requirements.
1 The stiffness center of the vibration isolator and the mass center of the vibration isolation system should be on the same vertical line;
2 The distance between the center of mass of the vibration isolation system and the line of action of the disturbance should be reduced;
3 The vibration isolators should be arranged in the same horizontal plane;
4 When arranging vibration isolators and dampers, space for installation, maintenance and replacement shall be reserved.
3.2.3 When the calculated horizontal displacement of the vibration isolator or damper exceeds the limit value, a horizontal limit device shall be installed, and it shall be separated from the vibration isolation object and the base structure.
3.2.4 When the stiffness of the base of the vibration isolation object cannot meet the requirements, a pedestal structure should be provided.
3.2.5 Pipelines and vibration isolation objects should be connected flexibly or provided with elastic supports.
3.2.6 The determination of the damping ratio of the active vibration isolation system shall meet the following requirements.
1 The damping ratio of the vibration isolation system shall be calculated according to the following formula.
In the formula. ξ——the damping ratio when the vibration isolation system vibrates along the χ, y, and z axes;
ξφ——the damping ratio when the vibration isolation system vibrates around the χ, y, and z axes;
Fv——At the operating speed, the disturbance force (N) acting on the mass center of the vibration isolation system along the x, y, and z axes;
Mv—disturbance moment acting on the mass center of the vibration isolation system around the x, y, z axes (N m);
[u] - allowable vibration displacement of the machine (m);
[uφ]——the allowable vibration angular displacement of the machine (rad);
K——total stiffness of the vibration isolator along the x, y, and z axes (N/m);
Kφ—total torsional rigidity of the vibration isolator around the x, y, and z axes (N m/rad);
ωnv——the natural circular frequency of the vibration isolation system vibrating along the x, y, and z axes (rad/s);
ωφnv——The natural circular frequency of the vibration isolation system rotating around the χ, y, and z axes (rad/s);
ω——interference circle frequency (rad/s).
2 For impulse vibration, the damping ratio shall be calculated according to the following formula.
In the formula. ωn—the undamped natural circular frequency of the vibration isolation system vibrating along the x, y, z axes (rad/s);
ωnφ——the undamped natural circular frequency of the vibration isolation system rotating around the x, y, and z axes (rad/s);
up——the maximum vibration displacement (m) under the action of pulse disturbance;
upφ——the maximum vibration angular displacement (rad) under the action of pulse disturbance;
ua—displacement (m) caused by the pulse disturbance after decaying time t;
uaφ——the angular displacement (rad) produced by the pulse disturbance after decaying time t;
t——vibration decay time (s).
3.2.7 During active vibration isolation, the quality of the pedestal structure should comply with the following formula.
In the formula. m1——mass of vibration isolation object (kg);
m2——the mass of the pedestal structure (kg);
Fz——the disturbance force (N) acting on the center of mass of the vibration isolation system along the z-axis.
3.2.8 The natural circular frequency of the vibration isolation system should be less than 0.4 times of the interference circular frequency, and should comply with the following formula.
In the formula. η—transmissibility of the vibration isolation system, which can be calculated according to the provisions of Article 3.2.9 of this standard.
3.2.9 The transmissibility of the vibration isolation system should meet the following requirements.
1 The transmissibility of passive vibration isolation should meet the following requirements.
In the formula. η—transmissibility of the vibration isolation system;
u—displacement of disturbance vibration (m).
2 The transmissibility of active vibration isolation should not be greater than 0.2.
3.2.10 The natural circular frequency of the vibration isolation system can be calculated according to the following provisions.
1 The natural circular frequency of a single-degree-of-freedom system can be calculated according to the following formula.
In the formula. ωnx——the undamped natural circular frequency of the vibration isolation system along the χ axis (rad/s);
ωny——the undamped natural circular frequency of the vibration isolation system along the y-axis (rad/s);
ωnz—the undamped natural circular frequency of the vibration isolation system along the z-axis (rad/s);
ωnφx——the undamped natural circular frequency of the vibration isolation system rotating around the χ axis (rad/s);
ωnφy——the undamped natural circular frequency of the vibration isolation system rotating around the y-axis (rad/s);
ωnφz——the undamped natural circular frequency of the vibration isolation system rotating around the z-axis (rad/s);
Kx——total stiffness of the vibration isolator along the χ axis (N/m);
Ky——total stiffness of the vibration isolator along the y-axis (N/m);
Kz——total stiffness of the vibration isolator along the z-axis (N/m);
Kφx—total torsional rigidity of the vibration isolator around the χ axis (N m/rad);
Kφy—total torsional rigidity of the isolator around the y-axis (N m/rad);
Kφz—total torsional rigidity of the vibration isolator around the z-axis (N m/rad);
Jx——moment of inertia of the vibration isolation system around the χ axis (kg m2);
Jy——moment of inertia of the vibration isolation system around the y-axis (kg m2);
Jz——moment of inertia of the vibration isolation system around the z-axis (kg m2);
m—the total mass of the vibration isolation object and the pedestal structure (kg).
2 The natural circular frequency of two degrees of freedom coupling vibration can be calculated according to the following formula.
In the formula. ωn1——The natural circular frequency of the undamped first vibration mode (rad/s) when the two degrees of freedom are coupled;
ωn2——The natural circular frequency of the undamped second mode shape when the two-degree-of-freedom coupling vibration occurs (rad/s);
λ1, λ2, γ—— calculation coefficients, which can be calculated according to the provisions of Article 3.2.12 of this standard.
3.2.11 The total stiffness of the vibration isolator may be calculated according to the following provisions.
1 For support type vibration isolation, it can be calculated according to the following formula.
In the formula. Kxi——stiffness of the i-th vibration isolator along the χ axis (N/m);
Kyi——stiffness of the i-th vibration isolator along the y-axis (N/m);
Kzi——Stiffness of the i-th vibration isolator along the z-axis (N/m);
χi——the χ-axis coordinate value of the i-th vibration isolator (m);
yi——the y-axis coordinate value of the i-th vibration isolator (m);
zi——z-axis coordinate value of the i-th vibration isolator (m).
2 For suspension vibration isolation, it can be calculated according to the following formula.
In the formula. L - the length of the rigid suspender (m);
R——When the rigid suspenders are arranged in a circle, the radius of the circle (m) can be taken.
3.2.12 Calculation coefficients can be calculated according to the following provisions.
1 Calculation coefficients λ1 and λ1 of supported vibration isolation can be calculated according to the following provisions.
1) When χ－φy coupled vibration, it can be calculated according to the following formula.
2) When y-φx couples vibration, it can be calculated according to the following formula.
2 Calculation coefficients λ1 and λ2 of suspended type can be calculated according to the following formula.
1) λ1 can be calculated as follows.
2) When χ－φy coupled vibration, λ2 can be calculated as follows.
In the formula. z—the vertical distance from the center of stiffness of the vibration isolator or the lower end of the suspender to the center of mass of the vibration isolation system (m).
3) When y－φx couple vibration, λ2 can be calculated as follows.
3 Calculation coefficient γ may be calculated according to the following provisions.
1) When χ－φy couples vibration, it can be calculated as follows.
2) When y-φx couples vibration, it can be calculated as follows.
3.2.13 The deformation of the support structure of the spring vibration isolator should not be greater than 1/10 of the spring compression. If it cannot meet the requirements, it should be included in the coupling effect between the support structure and the vibration isolation system.
4 active vibration isolation
4.1 Calculation regulations
4.1.1 When the vibration isolation system is a single degree of freedom, the vibration displacement at the center of mass can be calculated according to the following formula.
In the formula. ux—vibration displacement along the χ axis at the mass center of the vibration isolation system (m);
uy—vibration displacement along the y-axis at the mass center of the vibration isolation system (m);
uz—vibration displacement along the z-axis at the mass center of the vibration isolation system (m);
uφx——vibration angular displacement of the center of mass of the vibration isolation system rotating around the χ axis (rad);
uφy——vibration angular displacement around the y-axis at the center of mass of the vibration isolation system (rad);
uφz——vibration angular displacement around the z-axis at the center of mass of the vibration isolation system (rad);
Fx——disturbance force (N) acting on the mass center of the vibration isolation system along the χ axis;
Fy—disturbance force acting on the center of mass of the vibration isolation system along the y-axis (N);
Fz——disturbance force acting on the center of mass of the vibration isolation system along the z-axis (N);
Mx—disturbance moment acting on the center of mass of the vibration isolation system around the χ axis (N m);
My—disturbance moment around the y-axis acting on the mass center of the vibration isolation system (N m);
Mz—disturbance moment around the z-axis at the center of mass of the vibration isolation system (N m);
ηx—the transmissibility of the single-degree-of-freedom vibration isolation system along the χ-axis;
ηy—the transmissibility of the single-degree-of-freedom vibration isolation system along the y-axis;
ηz—the transmissibility of the single-degree-of-freedom vibration isolation system along the z-axis;
ηφx—transmittance of the single-degree-of-freedom vibration isolation system rotating around the χ-axis;
ηφy—transmittance of the single-degree-of-freedom vibration isolation system rotating around the y-axis;
ηφz—the transmissibility of the single-degree-of-freedom vibration isolation system rotating around the z-axis.
4.1.2 When the vibration isolation system is coupled vibration with two degrees of freedom, the vibration displacement at the center of mass should be calculated according to the following provisions.
1 When χ－φy coupled vibration, it should be calculated according to the following formula.
2 When y－φx coupled vibration, it should be calculated according to the following formula.
In the formula. uφ1——the equivalent angular displacement of the first mode of coupled vibration of the vibration isolation system (rad);
uφ2——the equivalent angular displacement of the second mode of coupled vibration of the vibration isolation system (rad);
ρ1—the ratio of the horizontal displacement to the rotation angle in the first vibration mode of the coupled vibration of the vibration isolation system (m/rad);
ρ2——The ratio of the horizontal displacement to the rotation angle in the second vibration mode of the coupled vibration of the vibration isolation system (m/rad);
η1—transmittance of the first vibration mode of the two-degree-of-freedom vibration isolation system;
η2—the transmissibility of the second vibration mode of the two-degree-of-freedom vibration isolation system.
4.1.3 The transmissibility of the vibration isolation system should meet the following requirements.
1 When the disturbance force and disturbance moment are simple harmonic effects, the transmissibility should be calculated according to the following formula.
In the formula. ξx——the damping ratio of the vibration isolation system along the χ axis;
ξy——the damping ratio of the vibration isolation system along the y-axis;
ξz——the damping ratio of the vibration isolation system along the z-axis;
ξφx——the damping ratio of the vibration isolation system rotating around the χ axis;
ξφy——the damping ratio of the vibration isolation system rotating around the y-axis;
ξφz——the damping ratio of the vibration isolation system rotating around the z-axis;
ξ1——the damping ratio of the first vibration mode of the two-degree-of-freedom vibration isolation system;
ξ2——the damping ratio of the second vibration mode of the two-degree-of-freedom vibration isolation system;
ξxi——the damping ratio of the ith isolator vibrating along the χ axis;
ξyi——the damping ratio of the ith isolator vibrating along the y-axis;
ξzi——the damping ratio of the ith isolator vibrating along the z-axis;
ωnx——the undamped natural circular frequency of the vibration isolation system along the χ axis;
ωny—the undamped natural circular frequency of the vibration isolation system along the y-axis;
ωnz—the undamped natural circular frequency of the vibration isolation system along the z-axis;
ωnφx——the undamped natural circular frequency of the vibration isolation system rotating around the χ axis;
ωnφy——the undamped natural circular frequency of the vibration isolation system rotating around the y-axis;
ωnφz—the undamped natural circular frequency of the vibration isolation system rotating around the z-axis.
2 When it is impacted by rear-peak tooth-shaped pulse, symmetrical triangular pulse, rectangular pulse, sine half-wave pulse and positive sagittal pulse, the transmission rate should be determined according to Appendix A of this standard.
4.1.4 The damping ratio of the first and second vibration modes of the dual-degree-of-freedom vibration isolation system should meet the following requirements.
1 When χ－φy coupled vibration, it should be determined according to the following provisions.
1) For the damping ratio of the first vibration mode, the damping ratio of the vibration isolator along the x-axis and the damping ratio of the vibration of the vibration isolator around the y-axis are taken to be the smaller value;
2) For the damping ratio of the second mode, the damping ratio of the isolator vibrating along the x-axis and the damping ratio of the isolator rotating around the y-axis can be taken as the larger value.
2 When y－φx coupled vibration, it should be determined according to the following regulations.
1) For the damping ratio of the first vibration mode, the damping ratio of the isolator vibrating along the y-axis and the damping ratio of the vibration isolator rotating around the x-axis can be taken as the smaller value;
2) For the damping ratio of the second mode, the damping ratio of the isolator vibrating along the y-axis and the damping ratio of the isolator rotating around the χ-axis can be taken as the larger value.
4.1.5 The calculation of vibration displacement at any point shall meet the following requirements.
1 When the working frequency of the simple harmonic disturbance force along each axis and the simple harmonic disturbance moment around each axis acting on the mass center of the vibration isolation system are the same and there is no phase difference in the action time, the vibration displacement at any point can be Calculated according to the following formula.
In the formula. uxL——the vibration displacement of any point of the vibration isolation system along the χ axis (m);
uyL——vibration displacement of any point of the vibration isolation system along the y-axis (m);
uzL——vibration displacement of any point of the vibration isolation system along the z-axis (m);
χL——X-axis coordinate value of any point (m);
yL——the y-axis coordinate value of any point (m);
zL——The z-axis coordinate value of any point (m).
2 When the working frequency of the simple harmonic disturbance force along each axis and the simple harmonic disturbance moment around each axis acting on the mass center of the vibration isolation system are the same and there is a phase difference in the action time, the vibration displacement at any point should be Take into account the effect of phase difference.
3 When the operating frequency of the simple harmonic disturbance force along each axis and the simple harmonic disturbance moment around each axis acting on the mass center of the vibration isolation system are different, the maximum vibration displacement of each axis at any point can be calculated according to the following formula calculate.
In the formula. uxL,max—the maximum vibration displacement of any point of the vibration isolation system along the χ axis (m);
uyL,max——the maximum vibration displacement of any point of the vibration isolation system along the y-axis (m);
uzL,max—the maximum vibration displacement of any point of the vibration isolation system along the z-axis (m).
4 When the disturbance force and moment are pulsed, the vibration displacement at any point can be calculated according to formula (4.1.5-1) ~ formula (4.1.5-3) of this article.
4.2 Rotary machines
4.2.1 Under the following conditions, the rotary machine should adopt foundation vibration isolation.
1 When the operating speed of the unit is close to the natural frequency of the foundation-equipment system;
2 When the foundation condition of the plant site is poor and prone to uneven settlement;
3 When the non-vibration isolation design cannot meet the vibration control requirements.
4.2.2 The vibration isolation of the foundation of the rotating machine should adopt the supporting type; vibration isolation...
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