SU1411368A1 - Support block of offshore stationary platform - Google Patents

Abstract

FIELD OF THE INVENTION The invention relates to hydraulic engineering. The purpose of the invention is to increase reliability when installed on a point due to the hydrodynamic qualities of the support block. On the tubular elements 1 of the supporting block, along its length, trapezoidal wings 2 are mounted, having a symmetrical bevel 3 of the leading edge 35-45 °. The wings 2 are arranged in pairs in the upper, middle and lower parts of the support block so that in the upper part the angle of attack is no more than + 10 °, in the middle - 0 °, in the lower - no more than -10 °. . In the middle part of the block, stabilizers, perpendicular to the plane of the wings 2, are installed on the tubular elements 1, which are intended for a stable orientation of the support block during the turn. The lifting hydrodynamic force created by the trapezoidal wings 2 contributes to the rotation of the support block. 6 Il. (Oh (L

Description

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The invention relates to hydraulic construction, in particular the construction of fixed offshore platforms.

The purpose of the invention is to increase reliability when installed at a point by increasing the hydrodynamic qualities of the support block.

FIG. 1 shows the supporting block, top view; in fig. 2 - the same, side view; in fig. 3 - trapezoidal wings mounted on a tubular element; in fig. 4 is a view A of FIG. 3; in fig. 5 - middle part of the block; in fig. 6 is a sequence of reversal of the support block.

On the tubular elements 1 of the support block, along its length, trapezoidal wings 2 are mounted, which have a symmetrical j bevel 3 of the leading edge 4, the value of 35-45 ° to reduce the drag i. Trapezoidal wings 2 are placed in pairs in the upper, middle and lower parts of the support block so that in the upper part the angle of attack is no more than + 10 °, in the middle I 0 °, in the lower no more than -10 °, and average I the part is located between the center of gravity of the I support block and its center of pressure. In I of the middle part of the block, stabilizers 5 are installed perpendicular to the plane i of the wings 2 on the tubular elements i, 1, and are designed for a stable orientation of the support block during the turn. The lifting hydrodynamic force created by the trapezoidal wings 2 contributes to the rotation of the support block.

The support block of the offshore fixed platform is mounted on a self-unloading transport barge 6 having adjustable ballast compartments. Barge 6 is intended for transportation over the sea I of the support block and its discharge at the point of construction. At the stern of the barge there is an I swivel frame 7, which helps to reduce the buck pressure on the stern of the barge 6 when the supporting block is discharged. ,

The turn of the support block is accomplished as follows.

The supporting block is transported by sea on the deck of the self-unloading barge 6. Upon arrival at the construction site of the fixed offshore platform, preparatory operations are carried out: removing the attachment of the support block to the deck of the barge b, ballasting the barge to trim it to the stern. When the angle of inclination reaches a value greater than the friction angle of the pair of support block — the deck of the barge begins the spontaneous descent of the support block from the deck of the barge 6. The turntable 7 leans back when the lower part of the support block passes through it, namely after passing through the vertical center of the weight of the support block beyond frame rotation axis

7. The immersion of the support block in the water begins with the head, the motion path is shown in FIG. one.

In the process of immersing on the support block, the following forces act: the lifting force of the displacement structural elements applied in the center of magnitude and directed vertically upwards, the force of gravity of the elements of the supporting block applied in the center of the gravity and directed vertically downwards, the force of water resistance to the movement of the support block, lifting force the hydrodynamic nature of the structural elements of the support block, the magnitude of which is increased due to the selection and arrangement of the traces of the wing 2, the profile of which is chosen so that they are zdaval possible high lift with less water drag, the force of inertia of the support block like body, dumped into water having a particular mass and speed.

The design of the support block is selected (as a result of calculations and on the basis of modeling) so that after immersion in water, the acting forces create a turning point resulting in the turn of the support block head up. As the support block turns to a vertical position, the magnitude of the turning point decreases and the support block reaches its equilibrium. Its resistance is ensured by a sufficient area of the waterline formed by the tubular surface elements of the support block.

Ballast (sea water) is fed to the tubular elements 1 to install the support block on the sea soil.

Claims (1)

Invention Formula The support block of the offshore stationary platform, which includes tubular elements and a turn mechanism for installing the block on a construction point, is characterized in that, in order to increase reliability when installed on a point by increasing the hydrodynamic qualities of the support block, the turn mechanism is made in the form of trapezoid wings mounted in pairs on the tubular elements of the support block in the upper, middle and lower parts of it, with the trapezoidal wings in the upper and lower parts of the block being installed at an angle relative to the the tubular element and, in the middle part, parallel to the axis of the tubular element of the block, with the front edges of the wings facing the tubular elements made with symmetrical bevel at an acute angle, and in the middle part of the block, stabilizers are installed perpendicular to the tubular elements plane of the wings. View A 0W.2.2 FIG. FIG. five 2 {/ fft / qy (pepeM / 770g a CTff r- ± j 3-cffpoc About 4i-time oro / 77 GS