US 3268107 A
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Description (OCR text may contain errors)
Aug. 23, 1966 s. c. sPERLlNG CONTAINER FOR HAZARDOUS MATERIALS Filed July 24, 1964 STEVENS C. SPERLING ATTORNEY United States Patent O 3,268,107 CONTAINER FOR HAZARDOUS MATERIALS Stevens C. Sperling, Watehung, NJ., assigner to Esso Research and Engineering Company, a corporation of Delaware Filed July 24, 1964, Ser. No. 334,853 14 Claims. (Cl. 220-63) The present invention relates to improvements .in containers for hazardous materials. It has particular application to a light-weight portable container or carrier for hazardous materials such as explosive compounds, e.g. blasting agents, propellants and the like. It has further application -to a carrier or container in which small quantities of powerful explosive compositions may be tired or detonated, the energy of the explosion being absorbed, or substantially absorbed, within the container itself.
IIn the prior art various containers have been devised for `many purposes, including the carrying of hazardous materials such as explosives, radioactive materials and the like. Generally speaking, these devices are designed for preventing the transmission of external shock to the contents, or -for preventing 4the passage of heat, radiation, obnoxious gases, etc., to their contents or to personnel in the immediate vicinity or environment. There is a special need 'hitherto unfilled, however, for a light-weight portable carrier or `container for holding explosive materials `and for also containing fragments, non-gaseous combustion products, etc., and for withstanding the shock of sudden combustion, explosion or detonation of various hazandous materials, particularly such materials as high ener-gy explosives and propellants. There is a particular need for carriers or holders of this character which can be handled and operated with reasonable safety. There is a need also for carriers or vessels designed [for containing intentional explosions and/or deiiagrations, e.g. to test small quantities of hazardous incendiary and explosive materials. In research on propellants for rockets, for example, actual tests on many experimental compositions must be performed in connection with research, c g. to determine their detonating and tiring characteristics. One object of the present invention, therefore, is to make available a safe but por-table carrier or container of the character just described.
A further object is to design a quick closing container of relatively light-weight materials that has sufficient strength to withstand explosions of test quantities of high energy materials within its interior, without bursting and without causing injury or danger to per-sons in the vicinity.
A further object of the invention is to design acarrier of the type described above which is adapted for safe handling, e.g. closing and opening, by remote control using a robot, mechanical hands or other equipment for performing 4the necessary opening and closing operations. Such operations obviously require that the structure be simple and that the closure means be easy to manipulate and sure of operation.
A still further object is to design a container of the character described above which is lined with an energyabsorbing inner container or vessel. The latter may be either an elastic 'or .inelastic structure, but it must be one which absorbs the shock Waves of deflagration or explosion effectively.
In general, the carrier or `container with which the present invention is concerned comprises a main outer carrier body or vessel that is fabricated from a high tensile strength material. The material should have high impact strength as well as tensile streng-th. Usually it will be a metal, preferably steel. Stainless steel is particularly preferred. A normal schedule l stainless steel container, fabricated of welded pipe and/ or suitable standard pipe fittings of the same ma-terial is particularly suitable for the main outer vessel proper. However, other steels, non-ferrous metals and even strong reinforced plastic materials may sometimes be used.
The main vessel is preferably provided with a removable cover, although in some cases the cover may be hinged if the hinge allows suitable free movement. The cover is preferably of a size to telescope neatly but not too tightly over the open top end of the main vessel. It also may preferably be made of conventional schedule 10 stainless steel welded pipe and fittings. The cover is preferably provided with its own independent bail or handle so that it can be handled, e.g. by mechanical apparatus and, preferably, so Ithat it can be handled separately from the main outer vessel.
In order to keep the cover element in place during a firing or an explosion, the `combined vessel-cover structure also includes a closure band Iof high tensile strength. Multiple bands may be used if desired. The band structure preferably is attached to the main body of the carrier, although movable with respect thereto. It is arranged, in closed position, to surround the vessel from top to bottom. It also surrounds the cover when the latter is in place. This closure band is preferably secured in pivotal manner on supports firmly attached to the main vessel so that it is always available and handy. It is preferably designed normally to pivot by gravity into the upright or cover locking position. Preferably the cover element itself is not lined. However, if desired, it may be provided, as the main vessel is, with a shock absorbing inner liner or a separate and removable inner vessel. Such liner or inner vessel may be either elastic or nonelastic, as is the case with the liner for the ma-in vessel.
In a preferred form, the main vessel is primarily cylindrical `in form with a rounded -or partly spherical bottom. The latter is drawn, forged or otherwise formed in the usual manner as employed for preparing stainless steel pipe and fittings of standard types.
The liner for the main vessel is fabricated preferably of an effective energy absorbing material. The liner may absorb the blast of the explosion by complete disintegration. A suitable material for such absorption of energy is a methyl rnethacrylate resin. A ycylindrical liner of methyl methacrylate is particularly suitable, especially if not in close contact with the outer wall structure. However, the liner can be any material, metal or plastic, of such tensile strength and/ or energy absorption properties that a considerable portion of the original blast enengy is dissipated before it reaches the main vessel. The main vessel, of course, is of strong structural material, i.e. it has a very high tensile strength.
The main outer vessel preferably is provided with legs so as to stand it upright on a suitable support such as a floor or table. It is preferably provided also with trunnions on which the bail, which holds the cover in place when the container is in use, may be pivoted. This permits the bail to move by swinging about the trunnions into or out of cover-holding position. The bail also may be used, either manually or by remote control handling devices, to lift the vessel and to transport it from place to place. In its preferred form, the bail is made self-positioning by placing the pivots or trunnions on which it is mounted above its center of gravity. When not otherwise held it will swing normally into its vertical cover-locking position, laut it can readily be swung out yof such position.
The upper part of the outer vessel is preferably necked in slightly so as to receive the cover element which, in exterior diameter, is preferably about the same size as the unreduced portion of the cylindrical walls of the main vessel. The cover element or lid has a domed or partly spherical top portion. It is preferably provided with its own hinged bail or handle so that it can be picked up and lifted by mechanical means as well as manually, e.g. for putting it in place on the vessel or removing it mechanically.
The invention will be more fully understood by reference to the following detailed description and to the drawings which illustrate a preferred embodiment thereof.
In said drawings:
FIGURE l is a side elevational View of a preferred form of apparatus made according -to the present invention.
FIGURE 2 is a sectional view, taken substantially on the line 2 2 of FIGURE l, showing the internal construction and certain additional details.
Referring now to the drawing, the main carrier or vessel 11 is a tank constructed of a material of high tensile and impact strength, e.g. of normal schedule l stainless steel. The tank is substantially of cylindrical crosssection, having a wall thickness appropriate to the particular use to which it is to be subjected. For example, it may be a section of a 6-inch or 8-inch stainless steel pipe, having a wall thickness of 1/8 to inches. These dimensions, of course, are not critical and may be widely departed from. The vessel is preferably of single tube side wall construction, with the bottom portion 13 formed separately and joined to the side wall structure by welding. If desired, the whole vessel may lbe forged or drawn Ifrom suitable stock, although this is not practicable with some grades of stainless steel.
While .stainless steel of the character described above is a highly desirable and suitable material for the main container, other materials may be used so long as they are sufficiently high in impact strength and tensile strength, and reasonably light in weight so that the device can be used conveniently. Non-metallic materials such as fiberglass-reinforced plastics of certain types may be employed so long as they have the essential tensile and impact strengths.
As shown in the drawings, the upper part of the side wall of the main outer vessel is necked in at 13'. Near the upper end of the necked portion, a plurality of portholes 15 are provided. These permit the escape of a certain amount of gas when deflagration takes place, but not enough to propel the vessel off the ground. In the construction shown, a small annular passageway is provided between the vessel neck and the lower portion of the cap or cover element when the vessel is otherwise tightly closed, as indicated at 17.
The cap or cover element 19 has generally cylindrical side wall portions 21 and a domed or partly spherical top surface 23. This member may be made in a single piece or a short cylindrical side wall section may have the domed top or end closure welded thereto. It preferably is so shaped and sized as to fit tightly around the upper end of the neck portion of the main vessel as indicated at point 25, but below this point the cylindrical wall of the cover, inside, is slightly larger than the outside of neck 13 so as to provide the annular channel 17 just mentioned.
The main vessel is provided with a pair of trunnions or stud elements 27, 29 which may be fastened in any suitable manner as by welding to the vessel wall. These elements are adapted to receive a pivoted band or bail assembly indicated generally at 30. The latter consi-sts, in the .form shown, of two strong metal bail elements 31 and 33, arranged substantially parallel with each other. They are fastened together and to a hub structure in any suitable manner, as by welding to a hub element 35 on either side. The hub elements 35 are provided with openings adapted to -be mounted respectively on the trunnions 27 and 29. The pivot points thu-s provided are located preferably well above the center of gravity of the bail elements so that the latter tend to swing into the vertical position as shown in FIGURE 1 when not held otherwise. However, the bail elements may readily be pivoted to other positions, such as the dotted line position shown in 4 FIGURE l, to permit application or removal of the cover to the main vessel.
Secured to the bails at the upper portions, where they begin to curve over the top of the cover element, are upwardly projecting standards or ears 37, 38. A pair of ears is preferably provided for each of the bail members 31 and 33, although a single pair may suice in some cases. Each pair of ears is joined by a bar or handle element 40, as best shown in FIGURE 2. By means of this handle 40, the whole vessel may be carried conveniently a-s by an ordinary bail and also may be lifted and manipulated by mechanical cranes or mechanical robots of various kinds. This facilitates remote control of the device when dangerous materials are being placed or exploded therein.
The cover member or lid 19 also is preferably provided with ears, as shown at 43, 4S. These are adapted to receive a bail 47. This bail is of common type suitable for lifting the cover by hand or by mechanical manipulating devices. It will thus be understood that the vessel 11 and the cover 19 can both be handled either manually or mechanically. Hence, the operations of assembling and disassembling these parts are very simple and may be readily performed by remote control.
The vessel 11, as previously mentioned, is preferably provided with suitable leg or st-and elements 51 which may be suitably fastened thereto in any conventional way, `as by welding. These normally hold the vessel in an upright position suitable for filling, closing and other manipulation, and rfor standing on an appropriate floor and other supporting surface. The vessel is prefer-ably provided with a false bottom X of stainless steel Iof moderate thickness, eg., 1/8 to inch. Other and eqivalent materials may be used but a at plate of good rigidity and high modulus of elastcity is preferred. In a typical case a lz-inch plate of standard stainless steel is found to be very satisfactory. YAs shown in the drawing, this plate is seated at the llet of the curved bottom. It can, of course, yield -by flexure, or even by bending in extreme cases, to take up a good part of an explosive shock.
Inside the main vessel, projecting up fr-om the stainless steel plate element X, there is provided la short tubular or cylindrical element 60. This is adapted to support or receive samples of explosive materials, e.g., for testing of detonation, etc. The stainless steel plate element X serves as an excellent shock absorber to protect the bottom of the main carrier and to lessen the stresses on other parts of the vessel. The receiver or sample holder may be of any suit-able size and shape for holding a sample of material t-o be fired or detonated. There is considerable demand for testing explosives, propellants, and other substances of this general character. The receiver 60 yis of appropriate form for test quantities of such material e.g., for an elongated rigid sample. As indicated in the dot-ted lines 61, FIGURE 2, a stick of explosive or propellant, etc., of appropriate size, may be placed in the receiver 60 and will be held upright and concentrically located within the vessel. In this position, the explosive or other hazardous material may `safely be transported or it m-ay even be detonated within reasonable quantities for test purposes. Obviously, some of these materials are sensitive to a dangerous degree .and it may be desir-able or even `essential to handle them by remote control or with mechanical hands Ioperated by personnel well protected behind a suitable barrier or shield.
An important feature of the present invention is the character and quality of the liner or inner vessel 70. This, when properly designed, makes it possible for the vessel to contain and absorb an explosive force and still be made of relatively light-weight materials. The liner is preferably a light-weight energy absorbent barrier of fairly high mechanical strength but of material particularly suitable for absorbing a large portion of the explosive force. It may be frangible, that is, it may be made of materials which largely or comple-tely crumble 0l dGCrepitate as the explosion takes place. In such case it must be replaced after each explosion test. On the other hand it may be made of material which has some resilience, such as foam rubber lor various expanded plastic materials, or some of the other foamed or cellular materials now being widely used, e.g., for insulating against sound and shock. In such ease it may not need frequent replacement. With either the elastic or inelastic material, the liner must minimize the load or shock and the disruptive forces applied to the outside wall structure. A properly chosen liner will greatly lessen the chance of failure, even in the case of unexpectedly powerful explosions.
The liner itself may be made of material which is either metallic or non-metallic. It need not conform closely to the inside shape of the carrier but may be itself a cylindrical vessel somewhat or even considerably smaller than the inside of the carrier. Since the liner must, in gener-al, be inserted through the mouth of the vessel, which preferably is somewhat reduced in diameter, the liner normally will either lbe deformable in character or it will have an outer diameter not greater, and preferably slightly smaller than than the inside diameter of the container neck 14.
In a specific example, a container made as described above, of stainless steel, was designed for a safe test charge of 8 gr-ams of a known type of explosive. It was tested with 17 gr-ams, which was ignited and exploded completely without breaking yor deforming 1the vessel.
It will be obvious that various changes may be made in design and structure without departing from the purpose or :spirit of the invention. As previously indicated, the outer vessel itself m-ay be made of certain non-metallic materials, such as reinforced fiber glass, or a combination of such materials with a metal shell may be used, for example, a laminate -of plastic bonded liber glass and strong stainless steel. A single wider bail element may be used instead of the double bail illustrated in the drawings. If desired, the bail member may extend only from the trunnions upwardly; however, it is preferably made in such a way Ias to fully surround both the vessel itself and the cover element. This gives additional insurance against bursting in case of explosion. As noted above, the cover also may be lined in the same manner as the main vessel, although commonly this is not necessary. It is intended by the claims which follow to cover the above invention and its obvious variations as fully as the prior art properly permits.
What is claimed is:
1. A portable carrier or container apparatus for holding and/ or testing hazardous materials, which comprises an open top vessel having an outer wall structure of high tensile and impact strength, an energy absorbing liner within said outer lwall, a telescoping cover element also of high tensile and impact strength for closing said open top, and a reinforcing band of high tensile strength capable of holding said cover against removal from said vessel during explosions of test magnitude within said vessel.
2. Apparatus according to claim 1 wherein the reinforcing band extends around both the vessel and the cover element.
3. Apparatus according to claim 1 wherein the reinforcing band is pivotally secured to the vessel and is adapted to swing about said pivot into holding position for said cover element.
4. Apparatus according to claim 1 wherein the vessel is provided with a pair of trunnions and the reinforcing band is pivoted on said trunnions well above its center of gravity.
5. Apparatus according to claim 4 wherein the reinforcing band is double.
6. Apparatus according to claim 1 wherein the vessel is provided with a rigid stand to hold it normally in upright position.
7. An apparatus for safe handling and/or testing of high explosives, propellants and the like which comprises, in combination,
(a) a main vessel formed of high tensie strength steel and adapted to resist high internal pressures 'with relatively thin walls,
(b) a replaceable liner for use within said vessel capable of absorbing high energy shock waves,
(c) a cover element also of high tensile strength steel and sized to telescope over the upper part of said vessel,
(d) a bail element of high tensile strength pivotally mounted above its center of gravity on said vessel and adapted normally to swing by gravity into holding position over said cover element, thereby to automatically lock said apparatus for safety, said bail also serving as a handle for mechanical handling of said vessel.
8. Apparatus according to claim 7 wherein the cover element also has its own bail for handling by remote control.
9. Apparatus according to claim 7 wherein the liner is of frangible material of high energy-absorbent character.
10. Apparatus according to claim 7 wherein the liner is of resilient porous material.
11. Apparatus according to claim 7 wherein the liner is smaller in external dimensions than the internal dimensions of said vessel.
12. Apparatus according to claim 1 wherein a transverse metal false bottom plate is included to absorb energy.
13. Apparatus according to claim 1 which includes a liner of resinous polymer.
14. Apparatus according to claim 7 wherein the liner is an acrylate polymer material.
No references cited.
THERON E. CONDON, Primary Examiner.
G. T. HALL, Assistant Examiner.