US2611504A

US2611504A - Hanger for floating roofs

Info

Publication number: US2611504A
Application number: US752018A
Authority: US
Inventors: Wilbur E Busse; Clifford M Orr
Original assignee: Chicago Bridge and Iron Co
Current assignee: Chicago Bridge and Iron Co
Priority date: 1947-06-03
Filing date: 1947-06-03
Publication date: 1952-09-23
Anticipated expiration: 1969-09-23

Description

p 1952 w. E. BUSSE ETAL 2, 11,504

HANGER FOR FLOATING ROOF'S Filed me 5, 1947 s Sheets-Sheet 1 ZZZ/Zzagjji/Egaaz izaev on? P 1952 w. E.. BU'SSE ETAL 2,611,504

HANGER FOR FLOATING ROOFS 3 Sheets-Sheet 2 Filed June 3, 1947 p 1952 w. E. BussE EI'AL 2,611,504

I HANGER FOR FLOATING ROOF S Filed June 5, 1947 s Sheets- Sheet 3 Patented Sept. 23, 1952 HANGER FOR FLOATING ROOFS Wilbur E. Busse and Clifiord M. Orr, Chicago; 111., assignors to Chicago Bridge -&.Iron Company, acorporation of Illinois Application June 3, 1947', Serial No". 752,018"

'Thisinvention-relates to :floating; -rooitanks, and mores-particularly; tora new and improved hanger means for supporting theshoes ofa floating roof. tank :against: the: side walls of the tank. :Floatingrroof, tanks adapted for. storingvolatile. liquids, such-as petroleum products, generally prise acylindrical tankand-a roof within the tanlsfioating upon the liquid contained therein.

"Rho-roof is generally madeof lesser diameter than the inner diameter ofthe tank to assure free vertical movement of the roof with changes inthe level of the liquid, and; accordingly means must be aprovided for-sealingthe space between the edges of" the roof and the tank to prevent excessive loss. of: liquid through evaporation and tdprevent. contaminationof the storedproducts by rain-fall, dust. and the like. v

Thespace. between the roof and the side walls are. generally sealed byproviding 'a plurality of shoes supported by the roof. and adapted to slidably. contact the inner wallsof thetank. An an-. nular seal of flexible material is. usually included to. seal the space 'betweenthe shoes. and .the. roof. Variousrmeansv have been. employed to support the. shoes. against. theside walls of. the tank, many oi. which have been extremely complicated in nature...

Wehave invented, and .are herein disclosing and. claiming, a new and improved shoe hanger meanspossessing noveland desirable features...

W The invention. will .be described in. the. em-. bodiment shown the. accompanying drawings. inwhich;

1 ,isla vertical. section through ,a portion.

Fig. 3;

is a View likeFig. l of. a modified form of. thedevice;

Fig. '1 isa. vertical. section along lines. 7-4, of Fig.6 and I Figs. .8 and-.9. are: views of. the lower portion of the. root; showing twormodified. forms of the. 213% paratus; shown in Figs. 1. ando.

Referring. now -tQ-thB drawings; it.- indicates a.

sidewall eta liquid. storage tank in which a. roof litiloats, theroofihayinga sidewalhlZ and a bot;

. I 11 Claims. (Cl. 220-26) 2 Q tom l3. A plurality of. shoes l4 are supported by means hereinafter more 'fully described,-against v the side walls of'the tank. The shoes-are con;-

structed oi flexible metal sheets andare provided with vertical stifiening means in the form of ver tical fiex-ures [5 in the shoe. These flexures permit some expansion and contraction of the shoe and also serve as vertical reenforcements for the shoe. A pair of brackets I6 and H are secured to the shoe adjacent its upper portion by b0lts1l8Each bracket is provided with afiat' portion l9 adapted to be held between the surface of the shoe and awasher'plate 2| against which the nuts 29 are drawn. Each bracket isfurther provided withan upstanding web 22 having a vertical "slot 23 formed therein. Extending through the slot 23' is a horizontal crossbar 24. The crossbar is generally cylindrical in shape and is permissibly ro tatable and" vertically slidable within the slots. The outer ends 25' of the crossbar press against the inner edge of the vertical flex-ores I5.

Welded to'the crossbar 24 a point generally midway between the two brackets is a main shoe hanger member 26. The shoe hanger is in the form of an angle iron which extends downwardly, from its point of connection to the crossbar to a firstcam 21. V

The first cam is "pivoted at 28 "between 'a pair of plates 29- and sil'weldedtothe bottom of the roof. Also pivoted to the

plates

29 and 30, at 31', is asecond camf32 engaging the first cam andhaving-secured'thereto a lever 33. A plurality of weights 34 are removably secured to the lever-33.

With the roof intheposition shown in Fig. 1, the lever 33 iselevated from a freely hanging position by" means of the cam means just described. Movement of the roof away from the side wall [6' would cause the hanger means 26'to rotatein a counterclockwise direction, which ro-.

tation would be transmitted to the lever through the. cams and cause thelever to rotate in-a clockwise direction toward a freely hanging position 3 force tending to return the roof to center within the tank.

In the modified form shown in Figs. 6 to 9 inclusive, similar reference mimerals have been employed to indicate similar parts, the main difference being in the means transmitting the force exerted by the lever to the shoe.

In Fig. 6, gear means designated '35, replace the cam means shown in the previous embodiment. The gear means comprise a gear segment 36 connected to the end of the lever 33 having a. plurality of teeth adapted to engage a second gear member 31. The member 3'! is connected to the lower end of the shoe hanger 2E5 inwardly of the pivot 28 and comprises two substantially

parallel plates

38 and 39. The plates are provided with circular rods 40 extending therebetween to act as teeth and adapted to engage the teeth of the segment 36, as shown.

In the embodiment shown in Fig. 8, a somewhat modified cam arrangement is shown comprising afirst member 4i connected to the lever 33 on the opposite side of the pivot 3! having a flat upward face 42 adapted to press against two raised

portions

43 and 44 on the under side of a cam member 45 connected to the shoe hanger 26.

In the embodiment shown in Fig. 9, the raised portion 43a. and 44a are provided on the lower face 42a rather than on the upper member 45a.

It can be seen that the weight of the shoes is transmitted by the hanger means to the roof to exert a. horizontal force thereagainst tending to move the roof away from the side walls. The magnitude of the force exerted by the shoes depends upon the angular position of the hanger 26. For example, movement of the roof away from the side walls causin the hanger to rotate in a counterclockwise direction moves the hanger means towards a horizontal position thereby increasing the inward horizontal force exerted against the roof. Conversely movement of the roof towards the shoe and side wall causes the hanger 25 to approach a vertical position, in which position the horizontal force exerted thereby becomes zero.

As is clear from the foregoing, the distance between the point of pivot 28 of the cam or gear member to the roof and the point of contact with the other cam or gear member supporting the lever arm varies with various positions of the lever arm. In the embodiment shown in Fig. 1 where the cam arrangement is employed, the pointof contact of the cam member 21 with the cooperating cam member 32 moves outwardly with increasing distance between the roof and the side walls to shorten the lever arm presented by the cam 21, that is, to shorten the distance between said point of contact and the point of pivot 28. The reverse is true upon decreasing distance between the roof and side walls. The force exerted by the lever arm increasesin a two-fold manner as the roof approaches the wall as elevation of the lever arm increases its moment While at the same time the distance between the point of contact of the cams and the point of pivot 28 increases, increasing that lever arm also. In the embodiment shown in Figs. 8 and 9 there are but two points of contact, that is, the point 43 and the point 44, hence the lever arm is of one dis tance when the point 43 is in contact and changes to a. second and longer distance when the right hand point 44 is in contact with the member 41. In the embodiment shown in Fig. 6, as many different lever arms may be provided as is desired.

4 In the particular embodiment shown, there are three determined by the position of the three teeth 40.

It can also be seen from the foregoing that the movement of the roof towards the side wall decreases the horizontal force exerted by the hanger means and shoes while at the same time the horizontal force exerted by the lever increases. The reverse is, of course; true upon the movement of the roof away from the side walls. We prefer to construct the means transmitting the force of the lever to the shoe whether such means be in the form of cams, gear segments or the other arrangements shown, so that the force exerted by the lever arm with increasing distance between the roof and the side walls decreases at least as rapidly (and preferably more rapidly) as the force exerted by the shoe increases with such increasing distance. In the preferred arrangement, therefore, the sum of the horizontal forces tending to move the roof away from the side walls decreases with increasing distance between the roof and wallsof the tank. a r

While we have shown and described ourinvention in its preferred embodiment, it is to be understood that it is capable of many modifications. Changes, therefore, in'the construction and ar-' rangement may be made without departing from the spirit and scope of the invention as disclosed in the appended claims. r r I We claim: f 1. In a liquid storage tank havin a floating roof, the roof having a lower portion normally immersed in the liquid stored in the tank and one or more shoes adapted to slidably contact the side walls of the tank, means for supporting the shoes including a hanger having one end connected to the upper portion of the shoe and having the other end pivotally connected tothe lower portion of the roof, a separate gravity operated weighted lever arm having one end free and having its other end pivoted to the lower portion of the roof and camming means intere connecting the roof end of the hanger and the pivoted end of the lever for elevatingthe lever arm from a position hanging freely from its point of pivotal connection to the roof, said'camming means transmittin the force exerted by the lever in its elevated positioninto outward pressure of the hanger against the shoe and increasing the force with decreasing distance between the roof and tank side wall. 2. The apparatus of claim 1 in which the camming means includes a first cam attached to the hanger and operatively engaging a second cam attached to the lever arm and the force exerted by the lever arm varies inversely as the distance from the roof to the side walls. V

3. The apparatus of claim 1 in which the camming means include a first gear means attached to the roof end of the hanger and operatively engaging a second gear means attached to the pivoted end of the lever arm, and the force exerted-by the lever arm varies inversely as the distance from the roof to the side walls. v

4. In a liquid storage tank having a floating roof, the roof having a lower portion normally immersed in the liquid stored in thetank and one or more shoes having vertical stiffening means and adapted to slidably contact the side walls of the tank, means for'supporting the shoes comprising: a hanger having one end pivotally connected to the shoe, said connection including a crossbar attached to the hanger and bearing against the stifiening means; theother end of the hanger-being hivdaiiyedhsetee to'the lower portioniof the roof, a separate gravity operated. weighted lever arm havingpn'e-end ireezandi-having dtsliother jend pivotally connected tothezlower sure offithe hanger agairist-tl feshoe. V 5: pantus oithe-ch'aracter described in claim 4 including a pair of brackets secured to the shoe, said brackets being provided with elongated slots and said cross-bar extending through said slots.

6. In a liquid storage tank having a floating roof, the roof having a lower portion normally immersed in the liquid stored in the tank and one or more shoes adapted to slidably contact the side walls of the tank, means for supporting the shoes comprising a hanger having one end pivotally connected to the upper portion of the shoe and having the other end pivotally connected to the lower portion of the roof, said hanger extending inwardly and downwardly from said point of connection to said second point of connection whereby the weight of the shoe exerts an outward force to press the shoes against the side walls, a separate gravity operated weighted lever arm having one end free and having its other end pivoted to the lower portion of the roof, a first cam attached to the other end of the hanger operatively engaging a second cam attached to the pivoted end of the lever arm, said cams elevating the lever arm from a freely hanging position and transmitting the force exerted by the lever in its elevated position into outward pressure of the hanger against the shoe, said force exerted by the lever arm varying inversely as the distance between the roof and the side walls, and the outward force exerted by the weight of said shoe varying directly as the'distance between the roof and the side walls, said cams being so constructed and arranged to decrease the outward force exerted by the lever arm with increasing distance between the roof and side wall at least as rapidly as the outward force exerted by the shoe increases with such increasing distance.

'7. The apparatus 01 claim 6 in which the first and second cam have an area of contact between the pivots connecting the hanger and lever to the roof, said cams being arranged to change the position of said area of contact relative to said pivots and to increase the distance between the area and the pivot connecting the hanger to the roof when the lever moves toward horizontal position.

8. In a liquid storage tank having a floating roof having a lower portion normally immersed in the liquid stored in the tank and one or more shoes adapted to slidably contact the side walls of the tank, means for supporting the shoes comprising a hanger having one end pivotally connected to the upper portion of the shoe and having the other end pivotally connected to the lower portion of the roof, said hanger extending inwardly and downwardly from said point of connection to said second point of connection whereby the weight of the shoe exerts an outward force to press the shoesagainst the side walls, a separate gravity operated weighted lever arm having one end free and having the other end pivoted to the lower portion of the roof, a first ge mane-attac ed to the 'othei the at said gearmeanselevating thelever arm from a 'irely hanging position and" transmitting the force exerted by the lever in-'its'-elevated position into outward pressure of thehanger against the shoe, said forceexerted by thelever arm "varying inversely 'as the distance between therooi and the-side walls-'yand' the outward force exerted by the weight otsaidshoe varyingdirectly as the distance betweerrthe roof and' the'si'de walls, said gearimeans being so constructed arrangedto decrease the outward force exertedby'Jthe-lever; arm with increasing distance between the roof and side wall at least as rapidly as the outward force exerted by the shoe increases with such increasing distance.

9. In a liquid storage tank having a floating roof and one or more shoes adapted to slidably contact the side walls of the tank, means for supporting the shoes comprising: a hanger having its upper end connected to the shoe and having its lower end pivotally connected to the roof, a separate gravity operated weighted lever arm having one end free and having its other end pivoted to the lower portion of the roof and camming means interconnecting the lower end of the hanger arm to the pivoted end of the lever arm to elevate the lever from a freely hanging position, said camming means transmitting the force exerted by the lever in its elevated position to said hanger whereby to urge said hanger toward rotation about its lower end to press the shoe against the side wall of the tank and to change the distance between the pivot of said hanger and the point of application of said force inversely to the distance between the roof and the sidewall of the tank.

10. In a liquid storage tank having a floating roof, the roof having a lower portion normally immersed in the liquid stored in the tank and one or more shoes adapted to slidably contact the side walls of the tank, means for supporting the shoes comprising a hanger having one end pivotally connected to the upper portion of the shoe and having the other end pivotally connected to the lower portion of the roof, said hanger extending inwardly and downwardly from said point of connection to said second point of connection whereby the weight of the shoe exerts an outward force to press the shoes against the side walls, a separate gravity operated weighted lever arm having one end free and having its other end pivoted to the lower portion of the roof, a camming means comprising teeth attached to the other end'of the hanger operatively engaging a second camming means attached to the pivoted endof thelever arm,

the roof and side wall at least as rapidly as the 7' outward force exerted by the shoe increases with such increasing distance.

11. The apparatus of claim 10 in which the camming means comprising teeth and the secto the roof, said camming means being arranged to vary the position of said area of contact with relation tosaid pivots and to increase the distance between said area and the pivot connecting the hanger to the roof when the lever moves toward horizontal position. WILBUR E. BUSSE. CLIFFORD M. ORR.

REFERENCES CITED The following references are of record in the file of this patent:

Number Number r STATES rA 'r'ENTs Name 5 Date" I :Wiggins Feb. 21, 1928 Schurmann Nov. 27, 1928 Einbeck Sept. 15, 1936 Kuehn Dec. 29, 1936 V Einbeck u; Jan. 31, 1939 Ulm Sept. 2, 1947 FOREIGN PATENTS Country Date Germany May 2, 1929