US2160360A - Storage tank for combustible and inflammable materials - Google Patents

Description

May 30, 1939. 2,160,360

STORAGE TANKFOR COMBUSTIBLE Ami INFLAMMABLE' MATERIALS 7 s. N. H ssAN Original Filed Jan. 5, 1933 INVENTOR.

mama any so. 1939 UNITED STATES ems v aromas rm roa comps-1mm AND W MATERIALS Sidney N. Hanan, New Yflf'k, N. r.

Substitute for abandoned application Serial No.

650.219, January 5, 1933. This application De- 7 camber 28, 1935, Serial No. 58,486 I 5 Claims. .(Cl. see-1).

This application is a substitute application to replace my abandoned application Serial No. 650,219, filed January 5, 1933.

In this application the following terms shall 5 be interpreted in accordance with these definitions: Y

Structural design-The modern engineering method of arranging and proportioning a structure or its elements by means of the application of mathematics and the physical sciences.

Structural member -A'ny of the elementary shapes listed in any. standard steel handbook or a built-up combination of said elementary shapes with or without plates.

Tie-A structural member designed to resist tension.

. Brace-A structural member designed to resist compression. The'term (tie or brace) designates a single member structurally, designed to perform the dual function of resisting tension or compression.

Spring (verb)--(Architecturally) To-curve as a structural arch.

(structurally) To react as a structural arch from the points of application of the induced thrusts.

-Springing line- (Archltecturally) In a vertical cross section thru anarch structure, the line marking the level from vwhich the structural arch springs. (structurally) The line joining the points of application of thethrusts induced by a structural arch.

Sm'inging plane-The locus of the springing line in a structural barrel arch. Structural arch A curved structural element spanning an opening and so proportion to resist the equilibrium curve of forces ac ng within the arch and also the thrusts producedby the resolution of the superimposed loads or pressures. Geometric arch-Any part of a curve, an arc.

I .This invention relates to atank used for the storage of combustible, inflammable or othe to roast certain external loads or pressure and.

86 also aspecified internal pressure. The standard specifications for tank design also embody the requirement that a specified factor of safety be maintained inthe structural part of the tank subjected to strain, that is, no structural material of which the tank is constructed and 5 which carries a load shall be strained beyond the state where the stress in the structural material divided into the stress at which the structural material actually breaks will exceed a specified amount. This specified amount is termed the factor of safety. Before pointing out the novelties in the construction ,of my tank -I will first describe and use as a comparative example a type of tank for the storage 'of inflammable or combustible ma-V terial which is at present oftenidesigned. The

type of tank referred to has the shape of a rectangular parallelepiped. When a tank of such form or shape is subjected to 'aninternal pressure all sides including the top and bottom are subjected to fiexure outward and tend to blow out. This tendency is resisted by tying each side to the side opposite, including the top and bottom by means ofsteel bars acting as tension members and structurally designed as such. It is therefore necessary to have a set of ties for every side surface including the top and bottom sides and in this case three sets of ties.

When'this type of tank is subjected to an ex- -.ternal pressure the sides, including the top and bottom, are subjected to flexure inward and tend to collapse; the tie members now act as braces since they are now in compression and therefore must be structurally designed as compression members.

A tank of the type just described is often used in practice even though it has many disadvan tages of'which some may be listed as follows:

(a) A set of.ties for every two opposite sides (including the top and bottom) is required.

(b), These ties must also be able to resist compression which requiresthat their. (L/R) ratio I the ratio of their length to their radius of gyration) must be so proportioned that they 45. can effectively function .as compression mem-' bers. This may necessitate an increase in the amount of material used in them or other costly methods of construction for the purpose of decreasing this (L/R) ratio.

(c) Due to the great number cities the construction is laborious, cumbersome and expensive.

(d) The plane figure of the tank is practically restricted to the shape of a' quadrilateral because of the obvious expense and dimculty involved in 55 tying or bracing the sides together if the shape were other than a quadrilateral. g

It has been my object in the design of my tank to invent a type of tank which is of an improved type of construction and a more efficient and economic structure than tanks now in public use. On comparing the construction of my tank to the construction of the tank previously described, it can be seen that the undesirable features (c) and (d) pointed out above, are eliminated and the undesirable features as pointed out-in (a) and (b) are reduced, thus producing a more efficient and economical structure.

This is done by curving the vertical sides 2 of my tank therefore causing the curved vertical sides 2 to become the major carriers of the load; acting as arches which are subjected to tension when the tank is subjected to an internal pressure and compression when it is subjected to an external pressure. Any thrust produced by the arch action is carried by a beam 3 placed substantially in the springing plane of the arch which in turn distributes it to members capable of resisting tension or compression 4 which are connected to the beams and the curvedvertical sides. This last mentioned arrangement of the structural beam and tension or compression members in conjunction with the curved vertical side makes the curved side capable of resisting stress independently of any other part of the tank and so the top and bottom flat surfaces may have the plane figure of any polygon and the same principle of curved vertical sides connected as described be applied. The arrangement as truss. It can therefore be used in a single unit or compounded in a series of units in place ofany or all flat sides of tanks now in public use.

I will now describe in greater detail how my tank is constructed and refer to the drawing herewith submitted.

Figure 1 is a plan drawing showing the ou line of the tank and the location ofthe steel therein. The outline of the tank is any polygon which is herein shown as an irregular polygon.

Figure 2 and Figure 3 are sectional elevations taken along the dot and dash lines designated as 22 and M respectively, and looking in the direction of'the arrowheads.

Fig. 4 is an enlarged detail of Fig. 2.

The top and bottom sides of this tank are horizontal flat surfaces shown in the'plan draw ing Figure 1 and designated by the number I and hereafter referred to by this number. The

vertical sides of this tank are curved surfaces having the outline of an arches shown on the section drawings Figure 2 and Figure 3 and designated by the number 2 and hereafter referred to by this number. All the sides are constructed of open hearth tank plate which overlapor abut each other, the seams being weldediThe sides 2 are bent attheir'ends to form a lap with which they are joined to the sides I.

. At the juncture formed where sides I meet the 1| side orioutside of the tank, since its purpose sides 2 a structural beam is placed either inand function is the same in either position. Thi

\ beam is connected at the juncture of the sides I and 2 by means of rivets or welds. These struc tural beams will hereafter be designated as 3.

The beams 3 are tied together by structural steel members acting as ties or braces which are welded'or riveted where they join or connect with the beam 3. These ties or braces will be hereafter designated as 4.

The sides I are tied or braced together by means of structural steel members which are connected where they join the sides by means of welds. These ties or braces will hereafter be designated by '5. 1

Having described the construction of my tank I will now describe the purpose and function of each detail mentioned.

When the tank is subject to an internal pressure the sides 2 are caused to act as arches in tension inducing a thrust produced at the juncture formed where the sides I meet the sides 2. This thrust acts inwards and tends to collapse the tank at this point. The structural beams 3 were placed at the junctures of the sides I and 2 in order to carry .and distribute this thrust to the braces 4. The braces 4 are subjected to compression transmitted by the beam 3 and are structurally designed as compression members. In this manner the collapsing tendency at this point is resisted.

While the action as just described is taking place in the sides 2 beams 3 and braces 4; the sides I are subjected to flexurg outward and tend to blow outward. This 'is resisted by the ties 5 which are structurally designed as tension members.

All structural steel members are designed inaccordance with standard structural design,

specifications to resist the stresses to which they are subjected to and maintain the factor of safety specified by the specifications.

When the tank is' subjected to an external 7 pressure tlie sides 2 are caused to act as arches in compression inducing a thrust at the juncture formed where the sides I meet the sides 2. This thrust acts outward and tends to push out the sides I at this point. The beams 3 carry and distribute this outward thrust to the braces 4 which now act as ties subjected to tension and are structurally designed to resist this tension. In this manner the tendency at this point for the sides I to be pushed out is resisted.

While the action as just described is taking place in the sides 2 the beam 3 and the ties or braces 4, the sides I are subjected to flexure inward and tend to collapse. This is resisted by the ties 5 which now act as braces and are therefore structurally designed to take compressiom Having described the construction of my tank and the function. and object of each structural unit, I make the following claims:

1. A storage tank for combustible and inflamspringing from said sides;' means for connecting the arcuated sides to the opposed top andbottom sides; means for joining the adjacent arcu-- ated sides to each other at their corner junctures;

structural members, anchoring the ends oiLiihew arcuated sides, cooperatively disposed and connected substantially between the opposed junc- ,tures of the arcuated sides and the top and bottom sides; and substantially vertical structural side to the perimeter of the bottom side and springing from said sides; means for connecting the arcuated sides to the opposed top and bottom sides; means for joining the adjacent arcuated sides to each other at their corner junctures; structural members resisting the inward or out-, ward thrusts produced at the ends of thearcuate sides, cooperatively disposed and connected substantially-between the opposed junctures formed by the .arcuated sides with the top and bottom sides; and substantially vertical structural members connected at points spaced throughout the opposed areas of the opposed top and bottom sides thus securing said sides against displacement.

3. A storage'tank for combustible and inflammable materials comprising; opposed substantially horizontal top and bottom polygonal sides of steel plates; angular sidewalls of steel plates which are arcuated and springing from the perimeter of the top side to the perimeter of the bottom side and connected to said sides; the adjacent arcuated sides being connected to each other at their corner junctures; structural members, resisting tension or compression, are horizontally disposed and connected substantially along the junctures formed by the arcuated sides with the opposed horizontal polygonal sides; substantially vertical structural members, capable of resisting tension or compression, are secured at points "'iioiried to each other by means of 'welds; opposed spaced horizonally along said opposed horizontal.

structural members thus anchoring the junctures against displacement inward or outward; and substantially vertical structural members, resisting tension or compression, are secured at points spaced throughout the opposed horizontal areas of the opposed horizontal sides, resisting their displacement inward or outward.

4. A storage tank for combustible and inflammable materials comprising; opposed substan-' tially horizontal top and bottom polygonal sides of steel plates; angular sidewalls of steel plates which are arcuatedand spring from the perimeter of the top side to the perimeter of the bottom side and connected to said sides; the adjacent arcuated sides being joined to each other at their corner junctures; substantially .vertical structural members, resisting tension or compression, are secured at points spaced horizontally along the junctures of the opposed horizontal sides and the arcuated sides, anchoring said junctures against displacement; and substantially vertical structural members, capable or resisting tension or compression, are secured at points spaced throughout the horizontal areas of the opposed'horizontal polygonal sides resisting their displacement inward or outward.

5. A storage tank for combustible and inflammable materials comprising; opposed substantially horizontal top and bottom polygonal sides of steel plates, said top and bottom sides being similar polygons with similar sides disposed symmetrically opposite each other; angular sidewalls of steel plates which are arcuated and springing from the perimeter of the top side to the perimeter of the bottom side and joined to said sides by means of welded connections; angular corner junctures formed by adjacent arcuated sides are horizontal channel members of steel are joined by means of welds, substantially at the perimeters of the opposed top and bottom sides, as coincident as is practicable with the junctures formed by the arcuated sides and the opposed top and bottom sides; substantially vertical angle members of steel are disposed at intervals along the said opposed horizontal channel members and joined to said members by means of welds; and substantially vertical angle members of steel are disposed at intervals throughout the horizontal areas of the opposed horizontal sides and joined tosaid horizontal sides by means of welds.

' SIDNEY N. HASSAN.

Images