A kind of double ship lifting dismounting offshore platform optics positioning mechanisms
Technical field
The present invention relates to marine engineering equipment fields, and it is fixed with optics to remove offshore platform more particularly, to a kind of double ship liftings
Position mechanism.
Background technique
Offshore platform is that the critical equipment of marine resources exploitation has nearly 8000 offshore platforms in the world at present.General sea
The projected life of upper mounting plate was at 20 years or so.According to relevant regulations, if without other purposes, the operation service life expire after must carry out
It is discarded to remove.This is of great significance to marine environment, navigation and the fish production etc. that ensure operating area.
Different from oil field development, platform, which throws aside itself, to bring direct benefit to platform owner, and this requires not
It is disconnected to reduce its expenditure cost.How more efficiently to carry out platform and throw aside operation, is the emphasis side that each Oceanographic Engineering Corporation considers
To.
It is exactly to carry out decomposition dismounting to offshore platform that each major oil companies, which take most straightforward approach, i.e., is extractd by crane barge
With fractionation upper chunk, resulting metal fragment and chunking are unloaded on a barge, then transported in ashore recycling
The heart.This method activity duration is long, is tens of days up to a hundred, is easy to produce environmental pollution, costly.Another method
It is overall pulling down method.Overall pulling down is realized using platform removal ship.Currently, Sweden shipowner Allseas possesses the current world
Upper maximum platform removal ship " Pioneering Spirit " number.The ship uses catamaran design, and fore is u-shaped, can be each
The side of drilling platforms is leaned against, fore is equipped with more scissors lifters, these cranes will entirely be weighed by single operation
Tens of thousands of tons of upper chunk is sling and is removed.This method activity duration is short, and couple of days can complete dismounting task, and platform can be again
Using or recycling, but expense is still very high.
Industry is proving a variety of schemes that may be decreased cost at present.A kind of more advantageous scheme is to utilize two
General semi-submersible type towboat replaces single dismounting ship of overall pulling down method, replaces lever lifting using water tank and supporting mechanism
Machine, as shown in Figure 1.This method is referred to as double ship lifting methods, and the course of work is that two same dynamic positioning semi-submersible types are dragged
Ship from two sides close to offshore platform, after hull support column is aligned with jacket (supporting the steelframe of offshore platform) support column,
Double ships start to float, and keep balancing by ballast water tank water, and platform upper chunking is promoted, moves on third carrying ship and transports
(as shown in Figure 2).
The first step using double ship lifting methods, which is two, has the semi-submersible type towboats of dynamic positioning ability from two sides by coastal waters
Upper mounting plate promotes upper chunk after being directed at hull support column with jacket (supporting the steelframe of offshore platform) support column.
This is the key that double ship lifting methods face.The method that industry uses at present is proximate to process using RTK GPS positioning, approaches
It is aided with the non-contact opticals localization method such as laser radar when jacket.In this way it is unilateral to be at least equipped with 2 laser radars could be into
Row precise positioning, higher cost.
Summary of the invention
It is an object of the present invention to overcome the above-mentioned drawbacks of the prior art and provide a kind of double ship liftings to remove
Offshore platform optics positioning mechanism.
The purpose of the present invention can be achieved through the following technical solutions:
A kind of double ship lifting dismounting offshore platform optics positioning mechanisms, to realize ship support column in double ship lifting methods
With precisely aligning for platform support columns, the hull support column lower surface opens up centrum groove, on the platform support columns
Surface is the convex cone of one with the cooperation of centrum groove shapes, which includes the laser emitter being mounted on in convex cone
With photosensitive sensor and the reflective mirror of centrum groove floor is set;
When carrying out alignment function, when ship support column and platform support columns misalignment, what laser emitter issued upwards
Vertical light acts in jacket support column base material, and reflection is weaker, and hull support column is not moved to alignment position at this time,
When ship support column is aligned with platform support columns, the vertical light that laser emitter issues upwards is acted on reflective mirror, is formed
Reflected light is received by photosensitive sensor and generates step signal, and hull support column is moved to alignment position at this time.
The radius of the reflective mirror is equal to the alignment precision of setting.
The reflection coefficient of the reflective mirror is higher than the material of jacket support column bottom.
The laser emitter uses laser diode.
The photosensitive sensor uses photo resistance.
The workflow of this optical alignment mechanism the following steps are included:
1) two dynamic positioning semi-submersible type towboats rely on RTK GPS positioning information from two sides close to offshore platform 0.5m range
It is interior;
2) connect hull support column at laser emitter and emit laser upwards;
3) control unit starts the information for receiving optical sensor while receiving GPS information;
4) when optical sensor is exported without step signal, show that hull support column has not moved to desired position, when
When optical sensor has step signal output, show the relative position of hull support column and jacket support column desired
In error range;
5) control unit checks GPS information, if GPS information also indicates that the opposite position of hull support column Yu jacket support column
It sets in desired error range, then starts to promote offshore platform.
Compared with prior art, the invention has the following advantages that
Offshore platform optics positioning mechanism is removed in double dynamical station keeping ship lifting proposed by the present invention, in side support stake dress
There are laser emitter and photosensitive sensor, the support stake of the other side is equipped with reflective mirror, and the radius of reflective mirror is made to be equal to desired pair
Quasi- precision is realized by the way that whether light-sensitive device receives the laser being reflected back to whether hull support stake is moved to desired locations
Judgement, blended with GPS information, effectively increase the precision and reliability of docking.
Detailed description of the invention
Fig. 1 is that double ship lifting methods remove offshore platform structure schematic diagram.
Fig. 2 is that double double boatman of ship lifting method make process schematic.
Fig. 3 supports stake to dock schematic diagram for hull support stake with jacket, wherein figure (3a) is structure when being aligned completely
Schematic diagram, figure (3b) are the structural schematic diagram under the limiting case of alignment, and figure (3c) is the required precision signal being reliably aligned
Figure.
Fig. 4 is configuration state figure of the present invention in misalignment.
Fig. 5 is configuration state figure of the present invention in alignment.
Specific embodiment
The present invention is described in detail with specific embodiment below in conjunction with the accompanying drawings.
Embodiment
As shown in figure 3, hull support column is docked with jacket support column using taper interface, this interface it is significant
Advantage is reduction of the requirement to alignment precision, theoretically, as long as vertebra point is fallen in inside support column largest circumference, hull support column
It can guarantee to be aligned under pressure with jacket support column.And requirement of the cylinder jack interface to precision is then much higher.
In practice, in order to guarantee the reliable of docking, the requirement to alignment precision is less than support column largest circumference radius.
In application GPS, the position of rover station constantly changes, and calculating coordinate is dynamically that there are systematic errors, reduce
Measurement accuracy.The large area water surface will generate strong reflection effect to electromagnetic wave signal, so that antenna receives simultaneously to be had directly from satellite
The signal of transmitting and electromagnetic wave signal from water-reflected, the observed quantity that both Signal averagings are formed, will produce positioning result
Raw Multipath Errors, can cause GPS signal losing lock when serious.In order to guarantee to dock, it is generally desirable to there are two types of or above mode
Guarantee the alignment precision of hull support column and jacket support column.Optical alignment mechanism proposed by the present invention is capable of providing a kind of essence
Higher means are spent, are used in combination with GPS, the safety of docking is improved.
It is as shown in Figures 4 and 5 that hull support column proposed by the present invention docks optical alignment mechanism with jacket support column, with original
For some hull support columns compared with jacket support column docking mechanism, optical alignment mechanism proposed by the present invention includes two portions
Point, a part is the laser emitter and photosensitive sensor being installed at hull support column, and a part is to be installed at jacket branch
The reflective mirror of dagger bottom.Laser emitter can be used but be not limited to laser diode, which has widely in laser pen
Using;Photosensitive sensor but it is not limited to photo resistance, is a kind of light-sensitive device being widely used;Reflective mirror is not wanted strictly
It asks, as long as reflection coefficient is apparently higher than the material of jacket support column bottom.The radius of reflective mirror is equal to desired alignment
Precision.When misalignment, laser emitter issue vertical light act in jacket support column base material, reflection compared with
It is weak, show that hull support column has not moved to desired position.When aligned, the vertical light that laser emitter issues acts on
On reflective mirror, the biggish reflection of intensity is formed, is received by light-sensitive device and generates step signal, notifies control unit hull support
Column is moved into desired position.Control unit improves docking by the fusion to GPS information and photosensitive sensor information
Precision and reliability.
Platform upper chunking promotion is finally moved on third carrying ship and is transported by double ship lifting methods.It is proposed by the present invention
Docking optical alignment mechanism is similarly applied to fixation of the platform upper chunking on carrying ship, and specific implementation step is as follows:
1, two dynamic positioning semi-submersible type towboats rely on RTK GPS positioning information from two sides close to offshore platform 0.5m range
It is interior;
2, the laser emitter at hull support column is connected, and starts to emit laser;
3, control unit starts the information for receiving optical sensor while receiving GPS information;
4, when optical sensor is exported without step signal, show that hull support column has not moved to desired position;
5, when optical sensor has step signal output, show the relative position of hull support column Yu jacket support column
In desired error range;
6, control unit checks GPS information, if GPS information also indicates that the opposite position of hull support column Yu jacket support column
It sets in desired error range, starts to promote platform.