FR2781555A1 - Container for high-pressure fluids such as compressed air has inner cells formed by flat sided plastic tubes linked through holes in their walls - Google Patents

Abstract

A high-pressure container has its inner volume divided into cells by a number of first-sided metal or plastic tubes (1-10) of relatively small section. The tubes are of triangular or other geometrical cross-section, have sealed ends, at least one lateral hole (11) to allow for circulation inside the container, and one or more end openings for filling or emptying. In one variant the tubes can be octagonal in section with outer lengthwise reinforcing windings and triangular section fillets to fit external gaps.

Description

CONCEPT 'AND METHOD OF MANUFACTURING A FLUID TANK,

  HIGH PRESSURE COMPRESSED OR VERY GAS AIR.

  The invention relates to high pressure gas or fluid tanks, in particular for land or sea vehicles and more particularly for those operating with injection of additional compressed air, and comprising a tank.

high pressure compressed air.

  High pressure compressed gas tanks have long been produced in steel cylinders, however, recently, tank designers have sought to lighten them either by using light metals such as aluminum, or by incorporating windings of them. fiberglass, carbon or other

  techniques called filament winding.

  In these cylindrical tanks the axial forces are good

  obviously proportional to the cross-sectional area of the cylinder as a function of diameter-

  they are generated by the pressure of the gas or the fluid which imposes considerable wall thicknesses as soon as the diameter of the cylinder becomes relatively large in order to obtain volume capacities, for example for a tank with a diameter of 300 mm containing a gas at 300 bars the axial force is 212 tonnes. In

  in addition, the radial and axial forces are collected by the same wall.

  Another difficulty of this type of tank is to install the fittings allowing filling and emptying which impose significant reductions in diameter on its nozzle which, due to the surface of the section undergoes stresses.

particularly important.

  Whatever the materials used, these very high forces require heavy tanks with very large wall thicknesses, for example more

15 millimeters.

  The invention proposes to resolve these defects, it is characterized in that the reservoir consists of several tubes of small sections forming juxtaposed cells glued to each other and connected to each other radially by at least one orifice to allow the circulation of gas. under pressure from one to the other, each tube or cell of relatively small diameter or section, for example 50 mm, collects its own axial forces, for example 5.9 tonnes for 300 bars and is closed by any means at its ends while at least one of these tubes receives at at least one of its ends a nozzle or orifice for filling and emptying the reservoir. All of these tubes or cells are then maintained by a common envelope made up of a composite coating of resin and fiber fabrics and / or filament winding or others. Radial forces are distributed over surfaces

  restricted and the common envelope helps to absorb these efforts.

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  These tubes can be juxtaposed cylinders, but the connection and bonding between them at a single point of the circle will be difficult to achieve, and we will prefer tubes with sections of geometric shape having flat faces allowing them to be juxtaposed and stick them together more easily such as triangle, square, pentagon, hexagon etc ... The juxtaposition of these tubes or cells allows the radial forces due to the pressure to oppose on either side of the juxtaposed and glued wall to

  that the walls of these tubes work only axially.

  The materials of the tubes can be made of metal such as steel, aluminum or others but preferably and according to one of the characteristics of the invention, each tube is produced with an internal envelope or liner in plastic material reinforced by composite materials and / or by filament windings of

fiberglass or other carbon.

  According to one of the preferred designs of the invention, the section of the tubes is an octagon and the latter are made of plastic, four of the sides of which serve as the basis for longitudinal filament windings while the other four sides are used for bonding and placing in communication, through holes drilled in correspondence, tubes between them. Each tube receives at each of its ends a glued octagonal plug, comprising or not, one or more O-ring seal and held axially and mechanically by the longitudinal filament winding. The tubes glued together form, seen in cross section, a square which can also serve as a tank if the ends have an adequate closure piece. Other objects, advantages and characteristics of the invention will become apparent

  on reading the description, without limitation, of several embodiments, made

  with reference to the accompanying drawings or: Figure 1 shows, seen in cross section and in perspective, a

  tank according to the invention comprising triangular cells.

  Figure 2 shows seen in cross section the same tank

  with its outer covering in composite coating.

  Figure 3 shows an octagonal section tank cell Figure 4 shows a cross-section view of a tank

of six octagonal cells.

  FIG. 5 represents an octagonal cell section with

  clearances for longitudinal filament windings.

  FIG. 1 represents, seen in cross section and in perspective, a high pressure gas tank according to the invention without its outer envelope, comprising ten tubes or cells of triangular section numbered from 1 to 10, juxtaposed

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  and bonded together with concordant orifices 11 which are drilled on the bonded common surfaces to put each cell in communication with each other which thus contain gas at an identical pressure. The radial forces on the walls of each cell are compensated for by the opposite forces of the juxtaposed cell arrow F while an outer envelope for retaining 12 FIG. 2 takes up the radial forces towards the outside of the tank and holds the ten cells between them glued

  giving cohesion to the entire tank.

  FIG. 3 schematically shows in cross-section and perspective, a cell of octagonal section, for the production of a reservoir according to the invention, comprising a sealing liner in extruded plastic 13 and longitudinal filament windings 14 produced in cross on four on the sides, and intended to collect the axial forces of each cell as well as to retain at the ends of the sealed shutters 15, inter-cell communication orifices 16 are formed on the other four faces of juxtaposition and bonding with the other cells constituting the reservoir, these orifices not being drilled on the faces

  communicating with the outside of the tank cell assembly.

  The cells are juxtaposed and glued to form a reservoir seen in cross section in FIG. 4 and delimit between them a volume of square section 17 which can advantageously also contain the gas under pressure making it possible to cancel the radial forces on the walls concerned of each cell, a sealed shutter being in this case located at each end of this volume of square section which is placed in communication with the octagonal cells. An outer holding envelope 18 in glass fabrics (or other materials and / or in filament winding) ensures the cohesion of the entire reservoir, and ensures the radial forces exerted by the pressure on the outer faces of the outer cells. The outer casing can follow the outer shapes of the octagonal cells, or according to a variant of the invention, triangular shaped profiles 19 made of polyurethane foam - or other materials - are positioned and / or glued between the octagonal cells and thus allow d on the one hand to better absorb the radial forces due to the pressure of the gases on the faces concerned, and on the other hand to obtain a

  tank with substantially flat blanks that are more easily produced and storable.

  According to a variant of the invention in FIG. 5, the octagonal cells 20 comprise on the four faces receiving longitudinal filament windings 14, a recess 21 making it possible to drown said winding in said recess. Of course, the geometric shape of the cell section, the closure systems at the ends of each cell and the filling systems

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  and / or emptying, the number of cells, the inter-cell bonding processes can

  vary without changing the principle of the invention which has just been described.

  As in place of or in addition to the filament winding, strips of glass fabrics or other fibers such as carbon, aramid, etc. impregnated or laminated can be used without changing the principle of

the invention described.

Claims (4)

CLAIMS S   1.- Fluid reservoir, under high pressure, in particular compressed air or other gas, characterized in that the reservoir consists of several tubes (1 to 10) of small section forming juxtaposed cells glued to each other and connected between they radially by at least one orifice (11) to allow the circulation of the pressurized gas from one to the other, each cell of relatively small diameter and / or section receiving its own axial forces and being closed by any sealed means at its ends while at least one of these tubes receives at at least one of its ends a nozzle or orifice for filling and emptying the reservoir, and characterized in that all of these tubes or cells are maintained by an envelope   common (12) which participates in the radial forces exerted on the walls of the cells.   2.- reservoir for pressurized fluids according to claim 1 characterized in that the tubes or cells have sections of geometric shape comprising planar faces allowing them to be juxtaposed and to bond them together more easily, such as a triangle,   square, pentagon, hexagon or others.   3.- pressurized fluid reservoir according to claims 1 and 2 characterized in that   that the cells have octagonal sections and are made of plastic, four of the sides of which serve as the basis for at least one crossed longitudinal filament winding (14) while the other four sides are used for bonding and for communication, by orifices drilled in correspondence (16), tubes between them, in that each cell receives at each of its ends a glued octagonal plug (15), comprising or not one or more O-ring seals and held axially and mechanically by the longitudinal filament winding, and in that the cells glued together delimit one, or more volumes of square section which can also serve as a reservoir if their ends   have an adequate sealing piece.   4.- pressurized fluid tank according to claim 3 characterized in that triangular shaped profiles (19) of polyurethane foam are positioned and / or glued on the periphery of the tank between the octagonal cells thus allowing better to collect the efforts radial due to the pressure of the gases on the faces concerned 5.- Reservoir of pressurized fluids according to claim 4 characterized in that each octagonal cell comprises on the four blanks receiving the longitudinal filament winding, a recess making it possible to drown said winding in the thickness of the step.