US3023934A - Transport container unit - Google Patents

Description

March 6, 1962 G. s. ROBERTS 3,023,934

TRANSPORT CONTAINER UNIT Filed Jan. 28, 1959 2 Sheets-Sheet 1 I I82 I32 m 252 FIGURE mrlll M W 24 24,

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FIGURE 2 March 6, 1962 G. s. ROBERTS 3,023,934 TRANSPORT CONTAINER UNIT Filed Jan. 28, 1959 2 Sheets Sheet 2 FIGURE 3 FIGURE 4 United States Patent ware Filed Jan. 28, 195). SP1. No. 789,623 4 Claims. (Cl. 222143) This invention relates to apparatus and a method for the transport of liquid products. More particularly, the invention relates to new and improved procedures and apparatus for the storage and transport of quantities of chemical and petroleum liquid products.

The transport and the storage of liquid chemical and petroleum products is a highly important branch of the process industries, and large investments in equipment are required for such service. In many instances, the most effective mode of transport involves the use of railroad tank cars, but, also, in numerous cases smaller quantities of liquids require movement and in some cases this has been accomplished by using returnable or disposable steel drums. A great need, however, has existed for effective means to transport intermediate or truck trailer quantities of liquid products. This would avoid the handling of drums in areas not served by rail. In addition, a significant need has existed for the transport of liquid commodities by ocean-going vessels. In the case of transport and storage in drums, water transport is relatively simple in that the drums can be trucked to the wharf and loaded on a vessel as deck cargo, but of course the cost of handling individual relatively small packages of this nature is out of proportion. This disadvantage also applies to smaller orders requiring only land movement.

In recent times a new variety of sea transport has developed employing a highway container unit, having maximum dimensions corresponding to a trailer body, and useable as such. Such containers are loaded in vessels having corresponding sized spaces or receptacles, these being fitted with means for registration and fastening down of the containers. It has been proposed to utilize, for liquids, a tank occupying such a modular size, a typical modular size being eight feet wide, about 35 feet long, and about 8 /2 feet high. If a cylindrical tank were provided to occupy most efficiently such a modular space, however (for example, about 7 /2 feet in diameter), the resultant weight would be excessive for highway use. There has been, heretofore, no efficient procedure or equipment, for land-sea transport of reasonable quantities of liquid products, which would use the above-mentioned modular space technique.

The trailer tank technique has been most highly developed for petroleum products, and especially for gasoline. For gasoline or other petroleum products, the design of tanks is relatively simple, and tanks of oval cross section are frequently used. In the case of many other commodities, however, such freedom in design is not available. When a liquid commodity has high vapor pressures, or is particularly flammable, the transport tanks are essentially unfired pressure vessels and therefore must satisfy the requirements of the appropriate code, particularly section VIII of the A.S.M.E. Boiler and Pressure Vessel Codes. When liquid products have the foregoing attributes, plus a high degree of toxicity, the requirements on pressure resistance are specific and rigorous. Thus, containers of circular cross section are virtually mandatory. The problem is further aggravated in cases wherein the liquid has a high density. As already explained, tanks of large cross section (occupying a full modulus) would not be transportable in highway service. Tanks occupying only one-half the height of a modulus, but of oval or rectangular shape, are unworkable because 3,023,934 Patented Mar. 6, 1962 of the pressure resistance requirement. Several individual, small cylindrical tanks, associated to provide a unit occupying half a modulus height, are acceptable but have the disadvantage of requiring dual hook-up at the charging and delivery locations.

Accordingly, a severe need has existed for a method and apparatus to provide transport of liquid chemical products sequentially by highway transport and then by water transport or vice versa. A need as outlined, wherein the apparatus includes a unitary container, has been particularly evident. By unitary is meant that a single volume container is provided or can be provided for the desired service. More particularly, a method and apparatus has been needed to permit such unitary container movement wherein cargo space on a vessel is in the form of rectangular compartments or stations having modular dimensions corresponding to the dimensions of a highway trailer body. Further, the method and apparatus required must conform to adequate safety requirements, such as the regulations of the Interstate Commerce Commission and the Coast Guard which take cognizance of the recognized codes for unfired pressure vessels such as the A.S.M.E. code.

An object of the present invention is, then, to provide a method and apparatus for the storage and safe transport of liquid chemical products by both highway trailer and water-borne means, without the need of separate tanks or containers on the vessel and the highway trailer. More particularly, an object of the invention is to provide equipment of the above indicated character which efficiently utilizes standard or modular sized compartments or spaces in a ship or vessel. A further and more specific object is to provide transport containers meeting the foregoing requirements and, further, which are highly effective and efficient for transport of hazardous liquid products. A further object is to provide a container of the foregoing type which is readily and economically fabricated of readily available materials or shapes. A further object is to provide containers or container units especially suited for transfer from a producing plant to a dock-side location and for loading from a highway vehicle to ships or barges. An additional object of preferred embodiments is to provide a container unit meeting the foregoing requisites, which also is susceptible or provides particularly efiicient and effective service to customer or consumer location, that is, by making possible single connections or unloading procedures in the place of the large multiplicity heretofore involved for shipments of commodities which were necessarily made in drums of relatively small capacity. Other objects will appear hereinafter.

The details of the invention and of the several illustrative embodiments thereof will be clear from the detailed description hereinafter and the figures, wherein:

FIG. 1 is a plan view of a simple form of one embodiment of the invention, wherein the container proper is in the form of an elongated U,

FIG. 2 is an end view of the embodiment shown in plan. by FIG. 1, FIG. 2 also showing the relative disposition of the unit and container comprising same with respect to a typical highway trailer employed for its trans-. port,

FIG. 3 is a plan view of a highly preferred and further embodiment of the invention, wherein the container proper is, in plan, in the shape of an elongated O, and

FIG. 4 is a further detail, in elevation, of a corner segment of the embodiment illustrated by FIG. 3.

The method of the present invention involves providing a container apparatus, having a unitary container in the most preferred embodiments, which occupies not more than one-half of a predetermined rectangular, boxlike shape or space comprising a modulus. Such container apparatus is transported individually, by attachment to a highway trailer and movement to a shipside location, and is then loaded on the ship. In the most efiective embodiments, the container apparatus units are stacked in pairs in the ship, to fully occupy the said modular spaces. Whether stacked as above mentioned or not, means are provided implementing such stacking of two units.

The preferred apparatus of the present invention comprises a container which includes two parallel cylindrical segments of equal or generally equal diameter, joined to at least one return bend segment. The return bend segment forms a 180 bend and has a cross sectional diameter equal, or approximately equal, to the diameter of the cylindrical segments. In all forms of the invention, associated with the container are support means at each end thereof, as described hereinafter. It is seen that, when one return bend is employed, the container resembles, in plan, an elongated U. In other highly effective embodiments, the container, in plan, resembles an elongated 0.

Each container is provided with at least one valve means or station for charging and discharging liquids, and in most of the preferred embodiments the said valve means is positioned on the upper portion of the return bend of the vessel or assembly. By valve means is meant, in most cases, a plurality of valves at a common general location so that, when loading a container through one valve, outage is provided for the vapors or gases therein, and conversely, when the vessel is being discharged, valve means permit entry of replacement gases or atmospheric air into the vessel. By providing a single or common location, only a single hook-up of the transfer lines and connections is necessary, in loading and in discharge of the contents.

At each end of the container proper are the support structures mentioned above. The structures may assume various forms, but in all instances they provide four bearing surfaces or points, positioned at the corners of a rectangle enclosing the entire apparatus. In addition to such bottom bearing or support parts, matching top elements, similarly positioned, are provided which are available for lifting the entire unit by appropriate hooks or other engaging means operated by a crane and for resting a like unit on top of the first.

In the case of embodiments having only one return bend section, the parallel elongated segments are fastened relatively rigidly one to the other at the ends which are remote from the return bend section, in order to achieve a high degree of gross rigidity, that is, rigidity of the one segment with respect to the other. The return bend segment contributes enormously to the provision of overall rigidity. In virtually all forms of the invention, extension means from the ends of the vessel are provided which join with corner posts forming part of the support structures, these being adapted so that the tank can be placed upon any flat surface, or also upon vehicles of the types mentioned above. The means of extension take various forms as will be clear hereinafter.

In a further, highly preferred and particularly effective apparatus providing one embodiment of the invention, two elongated cylindrical segments are again provided, these segments being joined one to the other at both ends by 180 return bends of substantially equivalent circular cross section. This provides a tank or vessel assembly having, in plan view, an elongated configuration, as previously mentioned. As will be clear hereinafter, this form of the invention is particularly effective in that the vessel itself provides an even higher degree of rigidity employing the steel of the container proper so that it is especially suitable for the services desired.

The several embodiments of the apparatus of the in vention will be fully understood from the description below. Referring to FIG. 1, this is a schematic plan view showing a typical embodiment of the invention from the top. It is seen that the apparatus includes a tank 11 of generally elongated U type configuration, the tank including two long segments 12;, 12 joined at one end to a return bend 12 The long segments 12 12 and the return bend 12 are of circular cross section of equivalent or equal magnitude, that is, the diameter of, and the wall thicknesses, of the sections being equal as well as the gross diameter. At one end of the assembly of the tank 11, that is the end in which the long segments terminate without joinder, extension segments 14 14 are provided, these being reducing type sections in this embodiment having a large diameter substantially equal to the diameter of the tank and being welded at the ends thereof. The actual termini of the tank space at this end is provided by conventional elliptical dished heads 13;, 13 The extension segments are permanently joined to an end transverse section which is generally a rectangular cross section and is bordered by reinforcing structural shapes such as angle irons 15. At the short dimensions of the end plate are placed corner posts 16 16 which provide for, generally, support of the apparatus when placed on a fiat surface or upon means adapted to engage the said corner post. In most instances, the corner posts are provided with sockets at the bottom, notshown, to engage corresponding members on vehicles or vessels when desired. It will be clear that the corner posts can serve in a dual function in that they provide a conventional support structure, as well as when desired, support plus alignment and registration functions. To provide further rigidity, particularly of the corner posts, tie rods 18 18 are desirably provided connecting the extremities of the corner posts 16 16 to the body of the tank 11 proper. Sockets 17 17 or similar elements, are provided at the top of the corner posts to receive or provide means for engaging and support of an equivalent unit in a stacked arrangement.

At the opposite end of the tank 11, namely, the end wherein the elongated segments 12 12 are joined by a return bend segment 12 additional extension segments 21 21 are provided protruding from the portion of the return bend segment 12 which is generally adjacent with the elongated segments 12 12 The extension segments, although of cylindrical cross section are blind segments serving as structural elements solely and connecting to a second end plate 22. This end plate, as with the end plate on the opposite end, is desirably provided with boundary reinforcement comprising structural shape such as channels or angle irons 23. The vertical boundaries of the end plate 22 are, again desirably provided by corner posts 24 24 which are fitted at their extremities with sockets 25 25 Valve means not shown are provided for the tank 11, positioned centrally on the return bend segment 12 and are covered by a hinged dome piece 26.

In addition to the lateral rigidity provided by the return bend segment 12 and the end plate and extension segments 21;, 21 further rigidity is provided as desired by cross members 19 19 which permanently connect the elongated segments 12 12 at intermediate points. The necessity of these intermediate members is dependent in part upon the dimensions and length of the container 11. As a matter of fact, in many instances the cross members are really not required for a fully adequate and safe design, insofar as rigidity of the container or tank is concerned. Such cross pieces do, however, provide suitable members for support of the unit on trailer frames or chassis. Recesses or projections therein, not shown, can be providedfor engaging mating elements on the trailer chassis.

The precise dimensions of an embodiment of the particular design illustrated in FIG. 1 and described above are not highly critical and are dependent upon the density, decomposition characteristics and vapor pressure, and other factors involved in the service for which the vessel or tank is intended. Among these factors are the gross dimension andweight limitations imposed by the governmental authority in the area or service for which the embodiment is intended. Thus, when the tank is to be employed solely in highway transport service in a particular state, the load and size limitations are substantially all that are required in that respect. However, in service involving or effecting interstate commerce and on the national highways, the regulations of Interstate Commerce Commission are also applicable. As illustrative of typical proportions of a tank of this embodiment intended for use in the transport of antiknock compounds, typical dimensions are as follows:

Total length approximately 30 feet.

Total width, not more than 8 feet.

Total height, approximately 4 feet, 3 inches.

The diameter of the elongated and return bend segments in such an embodiment can be from 18 inches up to and including 32 inches outside diameter. In other instances, for the indicated maximum exterior dimensions, outside diameters of up to roughly 36 inches can be permitted. The weight or thickness of the walls of the tank, also are dependent upon the applicable reguations and upon the physical properties of the materials involved. In a typical type of design, steel plate of onequarter to one-half inch thick is employed.

In service, a tank which is filled with the desired commodity and is in storage or in the loading spot in the producing plant, is lifted by suitable crane mechanisms, operating by attachment to the corner posts by appropriate socket engaging means or hooks. The tank is then positioned on the appropriate transfer vehicle, which can be a highway trailer or a railroad flat car or the like. In the case of highway trailers, highly effective service is provided by cradle or guide or registration means built into the trailer bed for engagement of various portions of the tank as desired. Thus, prongs or horns projecting from the highway trailer bed can engage the corner posts 17 17 24 24 for longitudinal and lateral registration on the trailer bed. In addition clamping devices, or securely fastened lashings of steel cable or chain can be employed to assure that the tank is held firmly in place on the trailer.

The relative disposition and approximate proportions of the tank container of the embodiment of FIG. 1 is shown in FIG. 2, being an end view of the unit in position on a highway trailer. The relative proportions of the corner post heights with respect to the carriage of the trailer are readily seen therein. Referring to FIG. 2, the end plate 22 of one end of the assembly is shown, the unit being in position on a highway trailer chassis 31. The trailer chassis includes a bed structure having at least two longitudinal frame members 32 32 with the appropriate cross beams or members 33. Usually trailers of this character are provided with tandem axles and dual wheels, only the rearward set 34 being shown herein. The unit rests upon suitable bolsters, not shown, which can be positioned generally adjacent the ends of the container 11. It will be seen, that the unit is suitable for resting on a fiat surface via the corner posts 17 17 24 24 as well as being adapted to engage a specific type of vehicle bed as described. In addition, by providing sockets in the bottoms of the corner posts equivalent to the top, engagement of appropriate support structures on ships is readily achieved. When a second unit is to be stacked on a first in modulus container or space on a ship, pegs are inserted in the tops of the bottom unit corner posts to provide engaging pins for the corner posts of the top unit.

To further illustrate the apparatus of the present invention and, more particularly, a highly preferred and specific embodiment thereof, FIG. 3 illustrates in plan view an embodiment involving, again, two elongated cylindrical segments, but in this embodiment the extremities at both ends being joined by return bend segments. Thus, referring to FIG. 3, it is seen that the container 41 of the embodiment includes two long segments 42 42 plus return bend segments 43 43 connecting the long segments 42 42 at the ends thereof. The support structure for the apparatus further includes, as in the preceding embodiment, corner posts 44 44 44 44 which, suitably can be connected at the top and bottom extremities by cross structural shapes or angles 45 45 the corner posts being provided at the top and bottom extremities with sockets as desired. A highly effective and significant feature of this embodiment, further, are extension means 46 46 46 46,, which provide rigid attachment between the extremities of the container tank 41 and the corner posts 44 44 44 44 The details of construction of a corner segment of the embodiment, illustrated generally in FIG. 3, is shown in FIG. 4, this being an enlarged view of one corner of the assembly including a corner post 44 and the extension means 46 Referring to FIG. 4, an elevation view of a segment of the apparatus is shown, showing a portion of the end structure of the unit. The corner posts 44 forming a part of the end structure, comprises, suitably, a cylindrical portion 47, and top and bottom enlarged segments 48 48 The enlarged segments include sockets, not shown, for receiving lifting devices, or for stacking on registration pins or similar devices on vessels or on flat bed vehicles, Attachment of the end structure to the container 41 is accomplished by an extension means or shape 46 joining the corner post 44 to both the elongated segment 42 and the return bend 43 This extension means 46 is a plate, curved in part, adapted to engage at one extremity a line contact with the tank, including a portion corresponding to a portion 49 of a peripheral segment of 42 The line contact continues on the surface of the tank 41 on the return bend portion thereof, and the other extremity of the extension segment 46 is a flattened out portion corresponding in long dimension to roughly the length of the cylindrical segment 47 of the corner posts 44 It is thus seen that the extension segment comprises a transition piece of unusual configuration in that a portion represents a transition from a straight line contact to a or thereabouts, line segment of a cylinder, the segment being in a plane parallel to the line contact of the other extremity, and the remainder of the transition piece being in continuous alignment and contact with the wall of the return bend. The configuration of the transition piece will also be readily understood by concurrent reference to FIG. 3 which shows, on a reduced scale, the plan disposition of the extension means. The innermost transition piece (viewed in plan) makes a 45 angle with the exterior boundary of the adjacent elongated segment. Tangent contact with the outside of the return bend is not essential. It will be seen that this structure is extremely effective in receiving and sustaining stresses imposed by the weight of the tank and contents on any support means such as the corner posts. Reference to FIG. 3 and FIG. 4 shows that lines of resistance to deformation provided between the corner posts in substantially all directions extending to the tank 41 proper. That is, linear lines parallel to the long dimension of the tank are provided, to provide for the maximum stresses, as well as lines at appreciable angles thereto extending to the return bend segment. Accordingly, the structure of the present embodiment of FIG. 3 and FIG. 4 permits a highly effective utilization of volumetric space. A unique advantage of the present design is the coordination of strength or stress resistance of the tank proper 41 with the means, typically the corner posts above mentioned, so that lifting or other forces applied to the corner posts, or other portions of the apparatus are resisted in unison and actually employing to a highly effective degree, the structure of the container proper. Thus, the weight of the accessory structure at the ends of the tank 41, in this embodiment, can be relatively low in total weight. The tank being a unitary device, including a closed loop of the long segment and the return bends, provides the rigidity and strength to a great extent of a single cylindrical vessel of equivalent capacity, but because of the relatively small cross sectional circular dimensions of any individual segment, compared to a single unit cylindrical tank of equivalent capacity, the wall thickness and height of the tank can be significantly lower. Accordingly, the embodiment of FIG. 3 and FIG. 4 is a highly preferred embodiment.

Access to the embodiment of FIG. 3, for loading and discharge of contents thereto is by valve means enclosed within a dome element 50. Cross members 51, 52 are provided, if desired, and can be fitted with bottom means, not shown, for engaging registration slots or holes or similar devices on the vehicles for which the tank is intended to be utilized. Thus, in the case of highway trailers, indentations or recesses on the cross members can engage corresponding projections, or vice versa, in the highway trailer bed or frame.

In the various embodiments of the present invention, the actual capacity can be further increased in desired instances by actually utilizing the extensions for storage space as such. In fact, in some instances these voids, provided by the extension, can be employed as supplementary storage spaces entirely compartmentalized from the tank proper. Thus, a'dverting to FIG. 1, the extensions 13 13 21 21 can be employed as additional space adjacent and connected to the tank proper 11. However, in most instances, in which the: present invention is employed, the cubic space provided by the extensions are not utilized for this purpose. However, when it is desired to accompany a particular commodity with minor quantities of supplemental liquids, separate valve means can be provided, for example, to the extension noted for the embodiment of FIG. 1, or to the extension means 46 46 46 and 46 of the embodiment of FIG. 3, so that the space provided by these structures is also utilized for transport purposes.

In fabrication and assembly of the apparatus of the present invention, careful workmanship is essential. Welds must be sound and the entire unit should be stress relieved and then pressure tested by hydrostatic pressure test. As to materials of construction, the particular method employed is determined by the commodity involved. When required alloy steels, plating or special lining coatings are provided. In most cases, conventional steels are quite suitable. Frequently, lagging or insulation, and

ornamental sheet metal jackets are provided.

Having described the invention in detail, what is desired to be claimed is:

1. A transport unit for liquid products including a pressure vessel container and support structure therefor, the container comprising two parallel elongated cylindrical segments of substantially equal diameter, and at least one return bend segment, the return bend segment having a circular cross section corresponding to the cylindrical segments and being joined thereto, and said container having valve means for charging and discharging liquids, the support structures being attached to the ends of the said container, said support structures providing a plurality of lower bearing surfaces, and defining a rectangle enclosing said container, and also having a corresponding number of support surfaces positioned above said bearing surfaces, for engaging a like unit and supporting said unit, said support structures incorporating means for lifting the transport unit, the lateral rigidity of the transport unit being provided essentially by the said container, and said return bend segment providing predominantly the twisting rigidity of the transport unit.

2. A transport unit for liquid products comprising a pressure vessel container including two parallel elongated c lindrical segments of substantially equal diameter, said segments being joined at one end by a return bend segment of substantially equal circular cross section, thus forming a continuous U-shaped container, and said container having only one valve means for charging and discharging liquids, said valve means being positioned at the return bend segment of the said U-shaped container, and two independent support structures in combination with said U-shaped container, one support structure including extension means projecting from the unattached ends of the cylindrical segments, said extension means joining to a first end structure, said first end structure including corner posts and a connecting frame and a second support structure including extension means attached to opposite sides of the base of said U and connecting to a second end structure including two corner posts and a connecting frame, the said corner posts defining a rectangle enclosing the container, each corner post having a bottom bearing surface means for support of the unit and top bearing surface means adapted to support a similar transport unit thereon, and lifting means associated with said corner posts for lifting the transport unit, lateral rigidity of the transport unit being provided essentially solely by the said container, and said return bend segment providing essentially the only means for imparting twisting rigidity to the transport unit.

3. A liquid transport unit for liquid products including a pressure vessel container and support structures therefor, said container comprising two parallel elongated cylindrical segments of substantially equal diameter, and two return bend segments of substantially equal circular Cross section corresponding to the diameter of the said elongated segments, the ends of the elongated segments being attached to the return bend segments, thereby forming a container of elongated O-shape, and valve means positioned in one of said return bend segments, the support structures including two independent support structures attached only to the said container at the return bend segments thereof, each said support structure including two bottom bearing surfaces for support of the unit and two uppermost supporting surfaces for engaging and supporting a similar transport unit thereon, lateral rigidity of the transport unit being provided essentially solely by the said container and said return bend segments being essentially the only means for imparting twisting rigidity to the transport unit.

4. The apparatus of claim 3 further defined in that the support structures at each end of the said container include a pair of corner posts, and a pair of transition members connecting said corner posts to said container, each transition member having one extremity comprising an elongated portion corresponding to and attached to the corresponding post and the other extremity being attached by line contact attachment to the container.

References Cited in the file of this patent UNITED STATES PATENTS 242,586 Berney June 7, 1881 277,428 Rothrock May 8, 1883 431,397 Ranson July 1, 1890 1,808,873 Weeks June 9, 1931 2,267,417 Nilson Dec. 23, 1941 2,332,410 Strothman Oct. 19, 1943 2,362,658 Meyer Nov. 14, 1944 2,503,210 OHalloran Apr. 4, 1950 2,632,577 Sacco Mar. 24, 1953

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