CN106225916B - The quantitative of fixed offshore platform security reliability, online detection method - Google Patents
The quantitative of fixed offshore platform security reliability, online detection method Download PDFInfo
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- CN106225916B CN106225916B CN201610616591.4A CN201610616591A CN106225916B CN 106225916 B CN106225916 B CN 106225916B CN 201610616591 A CN201610616591 A CN 201610616591A CN 106225916 B CN106225916 B CN 106225916B
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Abstract
The present invention relates to a kind of fixed offshore platform security reliabilities, the Quantitative Monitoring method of dangerous point location.On the horizontal plane of ocean platform spar deck outer, on eight due east, due south, due west, due north, the southeast, Nan Xi, northwest, east northeast directions, the measurement point being angularly distributed is established respectively, low-frequency acceleration sensor and velocity sensor are installed simultaneously in the vertical direction, due north horizontal direction, due east horizontal direction of same measurement point, measure vibration acceleration and speed of the fixed offshore platform spar deck in vertical direction, due north horizontal direction and the due east horizontal direction in this 8 measurement points respectively；With identical each sensor signal of sampling time interval synchronous acquisition, and respectively to the acceleration and speed progress phase difference calculating in the respective direction of each measurement point, using maximum phase difference as the quantized value of the measurement point safe condition.The present invention is realized 24 hours to the healthy and safe situation of fixed offshore platform and is quantitatively tracked.
Description
Technical field
The invention belongs to fixed offshore platform security reliability the study of the monitoring method fields, are related to a kind of fixed ocean
Online, the quantitative detection method of platform safety reliability.
Background technique
China is while a series of land large oilfields such as Daqing oil field, Zhongyuan Oil Field are built up, the Bohai Sea, the East Sea, the South Sea
Equal offshore oilfields are also accordingly exploited.Exploitation because of onshore oil field through many decades, their oil and gas production constantly decline, in addition, with
China increase in recent years in the demand interests of the energy, therefore it is just more and more important for the exploitation of offshore oil and gas field.At present, I
The marine petroleum development platform primary structure form of state is fixed offshore platform.Fixed offshore platform is suitable for several meters of the depth of water
To several hundred meters of waters.Under the action of marine environment random load, fixed offshore platform often generate fatigue damage and
Generate fatigue rupture, this on working platform deck staff's life and property safety cause greatly to threaten.In China
And the report for thering are many fixed offshore platforms to cause ocean platform collapse accident to occur due to various fatigue damages in world wide
Road.
Field is monitored in fixed offshore platform safe condition, there is presently no a kind of works using fixed offshore platform
Make the effective ways that the random micro-vibration of platform is analyzed, monitored.In fact, being sent out from the condition of fixed offshore platform safety
It opens up, prevent fixed offshore platform accident in the angle of possible trouble, then more to pay attention to the random micro-vibration of fixed offshore platform
Measurement and analysis.Collapsing for fixed offshore platform has a process, the generation of this process and development be one from
The process of quantitative change to qualitative change, in this process can to the analysis of fixed offshore platform spar deck platform microvibration measuring
It finds the problem as early as possible in time, and takes measures to formulate maintenance program immediately, by the reparation to fixed offshore platform and answer
The adjustment of power is come the generation for the peril that avoids collapsing.
Summary of the invention
In order to overcome the shortcomings of in existing fixed offshore platform safety monitoring technology, the present invention provides one kind with reality
When, dynamic mode, realize the detection method to quantitative tracking in 24 hours of fixed offshore platform safe condition.The present invention
Technical solution it is as follows:
A kind of detection method that fixed offshore platform security reliability is online, quantitative comprising following steps: step
S1: spar deck it is outer along the horizontal plane on, in eight due east, due south, due west, due north, the southeast, Nan Xi, northwest, east northeast directions
On, the measurement point being angularly distributed is established, measuring device is respectively arranged；Step S2: vertical direction, due north in same measurement point
Low-frequency acceleration sensor and velocity sensor are installed in horizontal direction, due east horizontal direction, realized to fixed offshore platform
Spar deck carries out dynamic measurement with the vibration acceleration of each horizontal direction and speed in the vertical direction in 8 measurement points；
The vertical direction of measurement point is wherein denoted as Z-direction, due north horizontal direction is denoted as the direction N, and due east horizontal direction is denoted as the direction E；
Rectangular coordinate system is established by origin of measurement point, wherein Z-direction is Z axis, the direction N is X-axis, and the direction E is Y-axis；Step S3: with phase
With sampling time interval, the vibration acceleration and vibration velocity of (X, Y, Z) in eight measurement points of synchronous acquisition spar deck
Signal；And the vibration acceleration and vibration velocity signal of spar deck in the X, Y, Z axis for obtaining 8 measurement points in ground are carried out respectively
Phase difference calculating obtains vibration acceleration of the measurement point in X, Y, Z axis to the phase difference value of vibration velocity；It is repeated several times and surveys
Measure the average phase difference value being calculated, the i.e. healthy and safe shape as fixed offshore platform in the measurement point and in this direction
Condition quantitative values；Step S4: it by the periodic detection to fixed offshore platform, records and tracks this measurement point phase difference of calculating
The variation of value, when phase difference value reaches critical value, dangerous change is had occurred in the safe condition for just corresponding to fixed offshore platform
Change simultaneously early warning；Step S5: carrying out relative quantification comparison by the phase difference value to each measurement point, so that it is determined that fixed ocean is flat
The dangerous point of platform and dangerous direction.
In an embodiment of the present invention, the low-frequency acceleration sensor and velocity sensor and fixed offshore platform work
Make deck rigid connection.
In an embodiment of the present invention, the sampling time interval is 10ms.
Further, the phase difference value calculates the following steps are included: with a synchronised clock and the same trigger signal
Multiple signal pickers are controlled, realize the fully synchronized acquisition of multi signal, guarantee vibration acceleration to the phase of vibration velocity
Difference computational accuracy；On the basis of synchronous acquisition, discrete fast Fourier transform is carried out to acquisition data, obtains signal
Phase-frequency characteristic, is thus calculated vibration acceleration to the phase difference value of vibration velocity, specifically: set vibration acceleration anIt is expressed asVibration velocity indicates vnFor
Wherein T is the period of vibration acceleration and vibration velocity signal, Am, VmRespectively each Fourier of vibration acceleration and vibration velocity
Leaf transformation amplitude,Respectively vibration acceleration and vibration velocity phase, TsFor the sampling interval；To anAnd vnIt carries out discrete
After Fast Fourier Transform, anAnd vnDiscrete spectrum characteristic in pth root spectral line be respectively
Then anAnd vnCorresponding phase difference isWherein NTs=pT, p are natural number；Take preceding 5 spectral line (p
=1,2,3,4,5) the sum of phase difference absolute value, as vibration acceleration to the phase difference value of vibration velocity.
The present invention carrys out real-time detection fixed offshore platform work first using low-frequency acceleration sensor and velocity sensor
Vibration acceleration and vibration velocity in all directions of plate, and each measurement point all directions vibration acceleration is calculated to vibration
The phase difference value of speed records and tracks this phase difference value.It can be realized the 24 small of fixed offshore platform by the method
When on-line real-time measuremen and dangerous point location, reflect the practical health status of fixed offshore platform in time.
Detailed description of the invention
Fig. 1 is flow chart of the invention.
Specific embodiment
In order to describe the technical content, the structural feature, the achieved object and the effect of this invention in detail, below in conjunction with specific implementation
Example is illustrated.
A kind of detection method that fixed offshore platform security reliability is online, quantitative comprising following steps: step
S1: fixed offshore platform spar deck it is outer along the horizontal plane on, due east, due south, due west, due north, the southeast, Nan Xi, northwest,
On eight directions of east northeast, the measurement point being angularly distributed is established；Step S2: horizontal in vertical direction, the due north of same measurement point
Low-frequency acceleration sensor and velocity sensor are installed on direction, due east horizontal direction, realizes and works fixed offshore platform
Deck carries out dynamic measurement with the vibration acceleration of each horizontal direction and speed in the vertical direction in 8 measurement points；Wherein
The vertical direction of measurement point is denoted as Z-direction, due north horizontal direction is denoted as the direction N, and due east horizontal direction is denoted as the direction E；To survey
Amount point is that origin establishes rectangular coordinate system, and wherein Z-direction is Z axis, the direction N is X-axis, and the direction E is Y-axis；Step S3: with identical
Sampling time interval, the vibration acceleration and vibration velocity signal of (X, Y, Z) in eight measurement points of synchronous acquisition spar deck；
And phase is carried out respectively to the vibration acceleration and vibration velocity signal of spar deck in the X, Y, Z axis for obtaining 8 measurement points in ground
Difference calculates, and obtains vibration acceleration of the measurement point in X, Y, Z axis to the phase difference value of vibration velocity；Meter is repeated several times
Obtained average phase difference value, i.e., it is fixed as the healthy and safe situation of fixed offshore platform in the measurement point and in this direction
Magnitude；Step S4: by the periodic detection to fixed offshore platform, calculating phase difference value is recorded and is tracked, phase difference value is worked as
When increasing to critical value, just corresponds to safe condition of the fixed offshore platform in corresponding measurement point respective direction and endangered
Danger variation and early warning；Step S5: quantitative contrast is carried out by the phase difference to each measurement point, determines the danger of fixed offshore platform
Dangerous point.
The low-frequency acceleration sensor and velocity sensor and fixed offshore platform workbench are rigidly connected.
In an embodiment of the present invention, the sampling time interval is 10ms.
Further, the phase difference value calculates the following steps are included: with a synchronised clock and the same trigger signal
Multiple signal pickers are controlled, to realize the fully synchronized acquisition of multi signal, guarantee vibration acceleration to the phase of vibration velocity
Potential difference value computational accuracy；On the basis of synchronous acquisition, discrete fast Fourier transform (FFT) is carried out to acquisition data, is obtained
The phase-frequency characteristic for obtaining signal, is thus calculated vibration acceleration to the phase difference value of vibration velocity.FFT can be carried out by computer,
Sampling number is bigger, and the frequency of resolution is more accurate.Specifically: set vibration acceleration anIt is expressed asVibration velocity indicates vnFor
Wherein T is the period of vibration acceleration and vibration velocity signal, Am, VmRespectively each Fourier of vibration acceleration and vibration velocity
Leaf transformation amplitude,Respectively vibration acceleration and vibration velocity phase, TsFor the sampling interval；To anAnd vnIt carries out discrete
After Fast Fourier Transform, anAnd vnDiscrete spectrum characteristic in pth root spectral line be respectivelyThen anAnd vnCorresponding phase difference isIt is adopted because synchronizing
Sample, therefore NTs=pT, p are natural number.The sum of preceding 5 spectral lines (p=1,2,3,4,5) phase difference absolute value is taken, is added as vibration
Phase difference value of the speed to vibration velocity.
In an embodiment of the present invention: the quantitative of fixed offshore platform security reliability, online detection method include
Following steps:
1. fixed offshore platform spar deck it is outer along the horizontal plane on, in due east, due south, due west, due north, the southeast, south
West, northwest, on eight directions of east northeast, angularly X, Y of distribution measuring point, in Z-direction, low-frequency acceleration sensor is installed respectively
And velocity sensor, the vertical and horizontal directions vibration acceleration and vibration velocity of fixed offshore platform spar deck are carried out
Dynamic measures；
2. sensor must be rigidly connected with spar deck, can totally tansitive spar deck vibration, at this
Vertical and horizontal low-frequency acceleration sensor and horizontal velocity sensor, the vibration to spar deck are installed simultaneously in measurement point
Acceleration and vibration velocity carry out dynamic measurement；
3. with identical sampling time interval (such as 10ms), the X, Y, Z axis of fully synchronized collecting work deck measurement point
Vibration velocity signal on vibration acceleration and X, Y, Z axis direction on direction, and to spar deck on the X, Y, Z axis direction of acquisition
Vibration acceleration and vibration velocity signal carry out phase calculation, obtain phase difference value of the measurement point on corresponding direction；It is measured
The phase difference value being calculated, the i.e. amount as the healthy and safe situation of fixed offshore platform on the corresponding direction of the measurement point
Change value；
4. the phase difference value that survey calculation obtains, which is up to, to be faced when situation deterioration healthy and safe due to fixed offshore platform
Dividing value.By the periodic detection to fixed offshore platform, simultaneously tracking and monitoring point phase difference value is recorded, is faced when phase difference value reaches
When dividing value, fixed offshore platform is just corresponded in the healthy and safe situation of the corresponding direction, dangerous variation and early warning has occurred；
Therefore it can realize 24 hours to the healthy and safe situation of fixed offshore platform and quantify in a manner of real-time, online and dynamic
Tracking.
The above description is only an embodiment of the present invention, is not intended to limit the scope of the invention, all to utilize this hair
Equivalent structure or equivalent flow shift made by bright specification and accompanying drawing content is applied directly or indirectly in other relevant skills
Art field, is included within the scope of the present invention.
Claims (3)
1. a kind of online, quantitative detection method of fixed offshore platform security reliability, which is characterized in that including following step
It is rapid:
Step S1: spar deck it is outer along the horizontal plane on, in due east, due south, due west, due north, the southeast, Nan Xi, northwest, east northeast eight
On a direction, the measurement point being angularly distributed is established, measuring device is respectively arranged；
Step S2: low frequency acceleration is installed in the vertical direction, due north horizontal direction, due east horizontal direction of same measurement point and is passed
Sensor and velocity sensor are realized to fixed offshore platform spar deck in the vertical direction in 8 measurement points and each water
Square to vibration acceleration and speed carry out dynamic measurement；The vertical direction of measurement point is wherein denoted as Z-direction, due north is horizontal
Direction is denoted as the direction N, and due east horizontal direction is denoted as the direction E；Rectangular coordinate system is established by origin of measurement point, wherein Z-direction is Z
Axis, the direction N are X-axis, and the direction E is Y-axis；
Step S3: with identical sampling time interval, the vibration of (X, Y, Z) adds in eight measurement points of synchronous acquisition spar deck
Speed and vibration velocity signal；And to the vibration acceleration and vibration velocity of spar deck in the X, Y, Z axis for obtaining 8 measurement points
Signal carries out phase difference calculating respectively, obtains vibration acceleration of the measurement point in X, Y, Z axis to the phase difference of vibration velocity
Value；The average phase difference value that survey calculation obtains is repeated several times, i.e., as fixed offshore platform in the measurement point and the direction
On healthy and safe situation quantitative values；
Step S4: it by the periodic detection to fixed offshore platform, records and tracks and calculate this measurement point phase difference value
Variation, when phase difference value reaches critical value, dangerous variation is had occurred simultaneously in the safe condition for just corresponding to fixed offshore platform
Early warning；
Step S5: being compared by the relative quantification that the phase difference value to each measurement point carries out different time of measuring, so that it is determined that solid
The dangerous point of fixed pattern ocean platform and dangerous direction；
The phase difference value calculates the following steps are included: controlling acquisition by a synchronised clock and the same trigger signal
Device is acquired low-frequency acceleration sensor and velocity sensor, to realize the fully synchronized acquisition of multi signal, guarantees vibration
Phase difference value computational accuracy of the acceleration to vibration velocity；On the basis of synchronous acquisition, acquisition data are carried out discrete
Fast Fourier Transform, obtains the phase-frequency characteristic of signal, vibration acceleration is thus calculated to the phase difference value of vibration velocity,
Specifically: set vibration acceleration anIt is expressed asVibration velocity indicates vnForWherein T is the period of vibration acceleration and vibration velocity signal, Am, Vm
The respectively Fourier transform amplitude of vibration acceleration and vibration velocity, Respectively vibration acceleration and vibration velocity phase
Position, TsFor the sampling interval；To anAnd vnAfter carrying out discrete fast Fourier transform, anAnd vnDiscrete spectrum characteristic in pth root
Spectral line is respectivelyThen anAnd vnCorresponding phase difference isIts
Middle NTs=pT, p=are natural number；Take the sum of preceding 5 spectral lines phase difference absolute value, i.e. p=1,2,3,4,5, accelerate as vibration
Spend the phase difference value to vibration velocity.
2. online, the quantitative detection method of fixed offshore platform security reliability according to claim 1, feature
It is: the rigid connection of the spar deck of the low-frequency acceleration sensor and velocity sensor and fixed offshore platform.
3. online, the quantitative detection method of fixed offshore platform security reliability according to claim 1, feature
Be: the sampling time interval is 10ms.
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| CN106908143B (en) * | 2017-03-01 | 2019-04-26 | 中国海洋大学 | Ocean platform monitors system and method |
| CN109110073B (en) * | 2017-06-23 | 2020-05-12 | 上海交通大学 | Early warning method, device and equipment for parameter resonance motion of ocean floating structure |
| CN111323116A (en) * | 2020-03-26 | 2020-06-23 | 中国水产科学研究院黄海水产研究所 | Marine culture platform deformation and vibration monitoring system and using method |
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