RU2307776C1 - Pontoon for vertical steel tanks - Google Patents

Abstract

FIELD: oil and petrochemical industries.

SUBSTANCE: invention can be used in tank farms of field and mainline oil and oil product lines, near-plant steel tank farms of oil processing and petrochemical plants, petroleum depots and sea and river terminals. Proposed pontoon contains stiffening ring, floats, net, covering, posts, sealing gate and vent pipe. Carrying structure is made of tubular sections bent to radius, stopped at end faces by plugs and welded to form torus-like ring with positive buoyancy. Outer diameter of pontoon is less than inner diameter of tank. Flat rings are welded to torus-like ring from inner side to increase rigidity. Flat rings are arranged in diametrically opposite planes. Flanges welded to vent pipe are fastened by guys. Covering is installed between guys resting on guys. Covering is made of foamed heat resistant chemically inert material nonswelling in stored product and reinforced by thread-like fibers. Covering has smaller density and larger volume than product forced out at dipping of pontoon.

EFFECT: reduced metal usage of pontoon construction, increased buoyancy, rigidity and heat resistance, provision of unsinkability of pontoon.

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Description

The invention relates to the oil and petrochemical industry and can be used in tank farms of field and main oil and oil pipelines, factory tank farms of oil refineries and petrochemical plants, in oil depots and sea, and river terminals.

Known designs of single-layer metal pontoons and fundamentally no different floating roofs, the buoyancy of which is provided by welding to the bottom, made in the form of a disk of sheet steel, peripheral side and stiffeners forming annular sector compartments [1].

The disadvantage of these designs is the unreliability of work due to the low rigidity, leading to a violation of the continuity of the welds during skewing of the pontoon, leakage and, as a consequence, flooding of the pontoon.

There are known designs of two-layer metal pontoons and floating roofs, the buoyancy of which is ensured by insulated sector compartments in the form of closed boxes of rectangular cross section formed by radial stiffeners in connection with bordering sides [1].

The disadvantages of these designs are their complexity, high metal consumption and length of welded joints, which leads to low reliability.

Closest to the technical nature of the proposed device is a pontoon in the form of a stiffening ring with a grid, supported by floats and covered with a carpet of synthetic film [1].

Among the design flaws of this pontoon are: the tendency of the coating material to swell and low bearing capacity and heat resistance, which leads to low reliability and short service life.

The technical result of the invention is to reduce the metal consumption of the pontoon structure, increase its buoyancy, rigidity and heat resistance, ensure unsinkability.

The technical result is achieved by the fact that the pontoon for vertical steel tanks contains a stiffening ring, floats, mesh, coating, racks, a sealing shutter and a ventilation pipe, and the supporting structure is made of bent along the radius of the pipe sections, plugged from the ends of the tubes and welded together into a mountain a ring with positive buoyancy and an outer diameter less than the inner diameter of the tank, and to increase the rigidity from the inside of the toroidal ring to it in the diametric planes flat rings are welded to the ventilation pipe — flanges fastened with cable ties, and the coating is installed between the cable ties and rests on them, and is made of heat-resistant foam, chemically inert and not swelling in the stored product, reinforced with filamentous fibers, having a lower density and greater volume than the product displaced by diving the pontoon.

Comparative analysis shows that the claimed device differs from the prototype in that the tube sections assembled into a ring, closed from the ends by plugs are supported by ring stiffeners with scarves and cable ties and simultaneously serve as floats and a supporting structure, and the mirror of the insulated product is overlapped by a layer that does not swell in the product and chemically inert foamed heat-resistant material placed between cable-stayed ties.

Thus, the claimed device meets the criterion of "novelty." Comparison of the claimed device with other technical solutions, analogues in the studied area (reservoir engineering), allows us to conclude that there are no signs similar to the significant distinguishing features in the claimed pontoon for vertical steel tanks, and to recognize the claimed solution meets the criterion of "significant differences".

The invention is illustrated by drawings, where figure 1 shows a General view and cross section of a pontoon for vertical steel tanks, and figure 2 is a top view thereof.

The supporting structure of the pontoon is made in the form of bent along the radius of the pipe sections 1, muffled from the ends by plugs 2 and welded together in a mountainous ring 3 with an outer diameter D _to less than the inner diameter of the tank D _p .

On the inner side, the toroidal ring 3, in diametrical planes to it, is supported by ring stiffeners 4 reinforced with scarves 5. In the center of the pontoon is a ventilation pipe 6 with flanges 7 welded to it and installed in its upper part with a valve and an arrester (to hell. shown). Annular stiffeners 4 and flanges 7 along their inner and outer periphery, respectively, are provided with stops 8 for attaching the tips 9 of the cable ties 10 and creating the necessary tension of the latter using inventory screw or hydraulic jacks (not shown).

Fixing the position of the tips 9 is carried out by a set of split washers-spacers 11.

On the annular stiffeners, guide glasses 12 are normally installed to them with the racks 14 passed through them and adjustable in height with the help of constipation 13 and glasses 15 with the tube guides 16 passed through them that are attached to the bottom and the roof of the tank (not shown).

In the space between the screw ties 10, a coating 17 is made of heat-resistant, chemically inert to the oil product stored in the tank and not swelling material in it. The reinforcing component of the coating 17 is a high-strength fiber, for example, of glass fibers. Fastening of the coating 17 to the stiffening ribs 4 and flanges 7 is carried out by a heat-resistant and chemically inert adhesive composition such as liquid glass to the stored product.

The supporting element for the coating 17 are the cable-stayed tie belts 10 made, for example, of high-strength steel ropes.

On the outer periphery of the mountain ring 3, an apron 19 is welded on which a locking device 20 is installed, which seals the gap between the pontoon and the tank wall.

In the initial position, the pontoon by means of racks 14, placed around the circumference on the annular ribs 4 in the guide glasses 12, is based on the bottom of the tank. Racks 14 are height-adjustable in accordance with technological requirements and requirements for the conditions of cleaning and repair work, and then are fixed by lock 13 in a predetermined position in the guide glasses 12. As the tank is filled with product, the pontoon pops up with the racks. In the floating position of the pontoon, the upper belt of cable-stayed couplers 10 operates. The lifting of the pontoon without a roll and the prevention of its rotation relative to the tank wall are ensured by the installation of vertical pipe guides 16 in the latter, and glasses 15 on the pontoon. The pipe guides 16 have perforation in their lower part, which makes it possible to carry out a number of technological and metrological operations - taking an average sample, measuring the level of the product in the tank, the position of the pontoon, etc.

The buoyancy of the pontoon is provided in two ways: by sealing the cavity of each pipe section 1 of the mountain ring 3 and plugs 2 and placing a coating 17 of material chemically inert to oil and oil products between the lower and upper rows of cable-stayed couplers 10, not swelling in them and having a bulk density much lower than the bulk density the latter.

The necessary tension of the cable-stayed couplers 10 is provided by adjusting the position of their tips 9 with screw or hydraulic jacks and fixing the position of the tips with split washers-spacers 11.

The ventilation of the sub-pontoon space after drying of the tank, necessary for repair and cleaning operations, is carried out using the pipe 6 and a safety valve and a flame arrester installed on it (not shown).

The upper position of the pontoon is monitored by duplicate signals of several sensors of the upper level of the product installed on the periphery of the upper zone of the tank (not shown).

Sealing the gap between the pontoon and the tank wall is carried out by any known locking device 20.

The inventive pontoon for vertical steel tanks has a much lower metal consumption than the known steel pontoons, is not inferior to them in heat resistance, has greater rigidity and is practically unsinkable. In terms of corrosion resistance to oil and oil products containing sulfur, it is much superior to pontoons made of aluminum alloys. Compared with a pontoon having a carpet made of synthetic film, the claimed pontoon is much more reliable, has greater heat resistance and a longer service life.

The inventive pontoon can be used both in construction and in operation or under reconstruction tanks for the storage of crude oils and petroleum products. Its use will dramatically increase turnaround times, i.e. reduce equipment downtime, and reduce maintenance costs, increase industrial and environmental safety.

Information sources

1. A.A. Korshak, A.M. Shammazov. Basics of oil and gas business. Textbook for High Schools: Ufa, LLC "DesignPoligrafServis", 2001, 544 p. S.327-330.

Claims (1)

A pontoon for vertical steel tanks containing a stiffening ring, floats, mesh, coating, racks, a sealing shutter and a ventilation pipe, characterized in that the supporting structure is made of pipe sections bent along the radius, plugged from the ends of the tubes and welded together in a mountain ring with positive buoyancy and an outer diameter less than the inner diameter of the tank, and to increase rigidity on the inside of the mountainous ring, flat rings are welded to it in diametric planes and to the ventilation pipe — flanges fastened with cable ties, and the coating is installed between the cable ties and rests on them and is made of heat-resistant foam, chemically inert and not swelling in the stored product, reinforced with filamentary fibers, having a lower density and greater volume than the product, displaced by diving the pontoon.

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