Abstract:
A tank for the transport or storage of liquified natural gas under pressure is of generally rectangular form and has its side, top and bottom walls each composed of a series of parallel lobes of part-spherical cross-section and of say, 3.0 to 4.0 meters chord distance, each tank end consisting of either a like series of lobes or a mosaic of domes. All the inter-lobe nodes of the top wall of the tank are united to the corresponding nodes of the tank bottom by vertical tie-plates; likewise all the corresponding inter-lobe nodes of the two side walls are united by transverse tie-plates which intersect the vertical tie-plates orthogonally, and thereby define with them a plurality of tunnels of square cross-section.The tie-plates extend longitudinally to unite the end walls of the tank and are welded to one another at all tie-plates inter-sections. The tank is supported on a series of parallel support ribs or frames that connect with the tank along the inter-lobe nodes of the tank bottom.
Abstract:
A secondary insulating barrier for protecting the hold of a ship below a spherical low temperature liquified gas storage tank installed therein comprises at least two layers of rigid foam synthetic resin sprayed on the hold plates and covered by a layer of glass mesh and adhesive. Alternatively, the layers of synthetic resin, glass mesh and adhesive are applied to plywood attached to the hold plates by joists, thus forming an air space between the secondary barrier and the hold plates. Where the hold plates have a multi-surface construction, laminated rigid urethane foam blocks are butted end-to-end and are bonded to each other and to the plywood sheets at the corners between adjacent hold plates, the spray-formed layers are applied between the blocks, and the whole is covered by a protective layer of glass mesh and adhesive.
Abstract:
A method of and an arrangement for building a cylindrical hollow structure such as a fluid storage tank, wherein lower and upper structural units to form lowermost and uppermost side wall portions of the hollow structure have helical upper and lower edges, respectively, and the upper structural unit is stepwise rotated about its axis and moved upwardly over the lower structural unit by the use of an open-end chain of link units supporting the upper structural unit in weight transmitting relationship to the lower structural unit through carriers rollably mounted on the helical upper edge of the lower structural unit while applying additional structural members to the upper structural unit for forming part of an intermediate side wall portion of the hollow structure and thereafter applying additional structural members to the helical lower edge of the intermediate side wall portion being constructed.
Abstract:
A spherical storage tank holding gases or liquids which is supported on a rigid concrete foundation in a region of the vertical axis of the tank. There is interposed between tank and foundation a mounting rigidly bonded to both the tank and the foundation having generally elastomeric properties. The mounting consists essentially of a plurality of slabs covering the whole upper area of the foundation, in a spaced array leaving only narrow gaps between the individual slabs. The slabs are thin in relation to their size, and the gaps between the individual slabs are filled with a soft-plastic sealant. Moreover, the foundation consists of an upper part and a lower part, between said upper and said lower part being interposed adjustable resilient pads to allow an adjustment of the upper part in relation to the lower part to correct the position of the upper part if the lower part has been displaced due to ground shock waves, underground cavations or the like. The lower part of the foundation has a surface loading as required to press on the ground soliciting it up to near its plasticity.
Abstract:
In the context of the handling of cryogenic materials, particularly liquefied natural gas (LNG), in marine loading systems, coaxial ducting links various plant sites of the system to provide in the one link both liquid transfer ducting and a return ducting for vapor of the liquid. Return of this vapor in the outer ducting helps thermally insulate the liquid in the inner ducting from the surrounding. The ducting is made up of rigid coaxial pipes swivellably connected together by swivel joints having no rolling bearing parts.Two particular arrangements of system are shown in one of which satellite loading buoys are linked to a main storage tank; in the other a main storage tank is fed with liquefied gas from a well head tower and has tanker-loading equipment itself. Loading equipment for a tanker may be comprised in the circuit which includes the coaxial ducting.
Abstract:
The invention provides a method and apparatus for detecting impairment of the integrity of barriers used for the containment of fluid materials, particularly fluid materials at cryogenic temperatures, e.g., liquefied natural gas. The detection system employs electrical conductors which are in physical relationship to the barrier and undergo a change in current conducting function in the event of barrier failure. In the containment of fluid at low temperatures the detection system preferably comprises conductors which have temperature dependent resistances and are embedded within the thickness of the barrier. By distribution of conductors over different notional zones of the barrier area and provision of associated warning devices the location of leakage points within the barrier area can be automatically indicated.
Abstract:
A ship having a hold containing a tank, for transporting a cryogenic liquefied gas, which is structurally free-standing and is spaced or separated from the ship hold walls, insulation secured to the ship hold walls and hold bottom, a ship hold cover extending over the tank top portion and joined to the ship, and a layer of loose fill insulation and a resilient blanket layer between the tank top portion and the ship hold cover.
Abstract:
The invention relates to a method of constructing large stationary cylindrical tanks using novel means for butt-welding together the horizontal joints of the cylindrical side walls of the tank. The novel means are flexible connector seals adapted to fit between the joints, and flexible portions of the seals are welded to the adjacent inner vertical surfaces of the side walls. Flexible connector seals are also provided for welding the bottom perimeter of the tank to the bottom edge of the cylindrical side wall.
Abstract:
In a method of positioning hoops of steel wire or strip for the application of circular prestress to pressure vessels provided at uniform intervals with peripheral support saddles, a winding core is placed between the saddles and the prestressing hoops and is displaced in rotational motion so as to wind the hoops. The device for carrying out the method comprises radial rollers and adjacent axial rollers so arranged as to form a roller track corresponding to the internal diameter of the winding core, at least one pressure roller for displacing the core and the hoop and at least one stationary drum for feeding steel strip.
Abstract:
A ship for the transporation of liquified gases at pressures approximately equal to atmospheric pressure and at temperatures substantially below ambient temperature has a double-hull structure with both the inner and outer portions of the hull made from an aluminum alloy having high strength and ductility at cryogenic temperatures. A layer of insulation is provided on the interior wall of the inner hull for thermally insulating the liquid gas cargo from the ambient temperature. A layer of an impermeable material, preferably in the form of a laminate, is disposed on the interior surface of the insulation layer to prevent gas/liquid leaks.