US3702636A

US3702636A - Antifreeze system for rack sprinkler building

Info

Publication number: US3702636A
Application number: US142997A
Authority: US
Inventors: John M Hart
Original assignee: Unarco Industries LLC
Current assignee: Unarco Industries LLC; Unarco Industries Inc
Priority date: 1971-05-13
Filing date: 1971-05-13
Publication date: 1972-11-14
Anticipated expiration: 1989-11-14

Abstract

An article storage rack, having tubular rack-support means constructed to convey a pressurized fire-extinguishing liquid therethrough, is adapted for use in environments that may be subject to freezing temperatures by providing a heat exchange conduit which conveys a heated fluid, such as glycol or steam, within the tubular support means and thereby providing a heat medium in heat exchange relationship with any fire-extinguishing liquid in the tubular support means. The heated fluid flow prevents the fire-extinguishing liquid from freezing and damaging the tubular rack-support means.

Description

United States Patent Hart [ ANTIFREEZE SYSTEM FOR RACK SPRINKLER BUILDING [72] Inventor: John M. Hart, Joiliet, Ill. [73] Assignee: Unarco Industries,-Inc.

[22] Filed: May 13, 1971 21 Appl.l 1o.:142, 997

52 us. c1 ..169/2 R, 169/5, 169/16 s 1 1m. 01 ..A62c 3/00 58 Field of Search ..169/2 R, 5, 16; 165/48, 53,

[56] References Cited UNITED STATES PATENTS 3,539,108 11/1970 Lillibridge et a1.. ..169/l6 x 3,255,084 6/1966 Doroszlai .;..-.....165/39 x 2,190,232 2/1940 Fry ..l65/39 [451 Nov. 14, 1972 3,520,345 7/1970 Lillibridge et al ..169/2 R Primary Examiner-M. Henson Wood, Jr.

Assistant Examiner-Thomas C. Culp, Jr. Attorney-Lettvin & Gerstman 57 ABSTRACT An article storage rack, having tubular rack-support means constructed to convey a pressurized fire-extinguishing liquid therethrough, is adapted for use in environments that may be subject to freezing temperatures by providing a heat exchange conduit which conveys a heated fluid, such as glycol or steam, within the tubular support means and thereby providing a heat medium in heat exchange relationship with any fireextinguishing liquid in the tubular support means. 'The heated fluid flow prevents the fire-extinguishing liquid from freezing and damaging the tubular rack-support means.

8 Claim, 9 Drawing Figures NTEDnnv 141912 SHEET 3 BF 5 lllvlll'l T I l l l I III QM M 1 ANTIFREEZE SYSTEM FOR RACK SPRINKLER BUILDING I BACKGROUND OF THEINVENTION .Thisinvention relates to a storage rack and sprinkler arrangement of the type in which the sprinkler fluid conveying conduits are arranged to act as support members themselves, and, more particularly, a new and improved arrangement for use in a frigid environment.

Fire sprinkler systems are usually required, by local law, to be installed in warehouses and other article sprinkler heads are frequently located a substantial.

distance from the stored articles and their storage racks, thereby substantially reducing the systems effectiveness in the event of fire. Also in 'such prior arrangements, the structural supports for the racks and/or building, when subjected to intense heat from a fire, frequently collapse resulting in extensive structural, personnel and article damage.

Another type of sprinkler system utilizes vertical tubular supports, which have spaced sprinkler heads thereon, and whichvertically support the racks while simultaneously conveying fire-extinguishing liquid to the sprinkler heads and cooling the vertical supports to resist collapse thereof when the structural supports are exposed to fire. This type of system, examples of which are shown in U.S. Pat. Nos. 3,520,345 and 3,539,108, substantially reduces the expenditure of both time and materials because the sprinkling assembly itself is utilized as a support structure. Further, the sprinkler heads can be arranged in close proximity to the stored articles to provide an effective extinguishing arrangement in the event of fire.

In frigid areas, such asawarehouse for frozen foods, it'has been found very difficult to provide an effective fire-extinguishing system because, when the fire is extinguished and the fire-extinguishing fluid becomes static and freezes, pipes may be broken, and in the type of system wherein the sprinkling assembly is itself utilized as a support structure, the support structure may split as a result of freezing of the fire-extinguishing fluid. Further, it is impracticable to thaw out and drain the entire system after a fire by heating up the warehouse area because there is possible loss of all of the frozen product in storage if the temperature of the freezer area is raised so as to thaw out the pipes and tubular supports.

I have discovered that the fire-extinguishing liquid which flows in vertical supports for article storage drained of fire-extinguishing liquid without effecting the temperature of the freezer and the articles stored therein.

It is accordingly a principal object of the invention to' provide a new and improved storage rack and sprinkler arrangement which utilizes tubular support means which are constructed to convey a pressurized fireextinguishing liquid therethrough and which have a heat exchange conduit located therewithin for conveying a heated fluid.

Typically in frozen food storage installations, glycol piping is built into the concrete floor slab construction so that hot glycol can be run through the pipes to prevent frost formation under the slab and consequent heaving and buckling of the slab. The glycol cannot be introduced directly into the fire-extinguishing liquid, which is generally water, because the glycol might eontaminate the food. However, I have found that the glycol piping can be connected to the heat exchange liquid flowing in the tubular vertical supports.

It is, therefore, an object of one embodiment of the invention to provide a new and improved storage rack and sprinkler arrangement wherein the rack is supported on a concrete surface having glycol piping thereunder, and in which the glycol piping is connected to heat exchange conduits which are located within vertical tubular supports which convey pressurized fireextinguishing fluid.

It is an object of another embodiment of the invention to provide a new and improved storage rack and sprinkler arrangement in a frigid environment wherein steam is introduced into heat exchange conduits which are located within vertical tubular supports which convey pressurized fire-extinguishing fluid, in order to prevent the fire-extinguishing liquid from solidifying.

These and other objects, features and advantages of the present invention will be more clearly understood racks can be prevented from freezing if a heat prevented from freezing and the entire system can be when considering the following detailed description.

. BRIEF DESCRIPTION OF THE DRAWINGS I FIG. 1 is a side elevational view of one embodiment of the storage rack and sprinkler arrangement of the present invention;

FIG. 2 is a side elevational view of the storage rack and sprinkler arrangement of FIG. I;

FIG. 3 is an enlarged perspective view of an upwardly directed header and sprinkler head embodiment for use in the arrangement shown in FIG. 1;

FIG..4 is a schematic diagram for the storage rack and sprinkler arrangement system of FIG. 1;

FIG. 5 is an enlarged fragmentary perspective view of the heat exchange conduit and fire-extinguishing liquid connections to one of the vertical tubular supports of the structure of FIG. 1, showing diagrammatically the connections for introduction of steam in accordance with a second embodiment of the present invention;

FIG. 6 is an enlarged fragmentary elevational view of a vertical tubular support, with portions broken away fro clarity; for

FIG. 7 is a schematic flow diagram of the glycol system in accordance with the present invention;

FIG. 8 is a sectional elevation showing the sprinkler and glycol piping in the lower portion of the arrangement shown in FIG. 1; and

FIG. 9 is a schematic flow diagram of the steam system in accordance with the present invention.

DETAILED DESCRIPTION OF THE ILLUSTRATIVE EMBODIMENTS Referring to FIGS. 1 and 2, one or more storage racks 10 are provided for the storage of articles. Each of the storage racks 10 includes a plurality of vertical supports 12 and a plurality of horizontal supports 14 extending along the depth and length, respectively, of the racks 10. All of the horizontal supports 14 (storage shelves) carry either the articles themselves or pallets filled with the articles.

The storage racks 10 are further vertically supported by vertical tubular supports 20 which are an integral part of the racks and which are interspersed between the vertical supports 12, as shown in FIGS. 1 and 2. These tubular supports 20 perform both the latter-mentioned support function as well as operate to deliver fire-extinguishing fluid, such as water, to the storage racks l and the articles stored thereon. To provide for ease in attaching the horizontal supports 14 to the tubular supports 20, the tubular supports are preferably square or rectangular in cross-section. Each of the tubular supports 20 is constructed of suitable materials and is of suitable thickness to withstand the pressure of the water therein and also the stresses produced by the structures which they support. More specifically, each of the tubular conduits, when finally installed, is adapted to pass the particular fire code test requirements of the locality for fire sprinkler systems which, for example, in some localities, is 200 p.s.i. for 2 hours.

As shown in FIG. 1, the vertical storage racks are spaced from each other to form access aisles therebetween. Although only two aisles and three racks are shown, it will be understood that any number of racks and aisles are contemplated. Each of the rack structures is braced by horizontal stringers 32 as necessary. Each of the central rows of supports has associated therewith one or more horizontally extending sprinkler headers 34 which are mounted on and communicate with various ones of the individual vertical tubular support conduit 20 of the aforesaid rows, the headers 34 each extending just beneath the next upper bin as defined by horizontal supports 14 or just beneath the roof of the building. The basic rack and sprinkler structure is described in detail in U.S. Pat. Nos. 3,520,345 and 3,539,108, which patents are assigned to the assignee of the present invention.

In freezers, warehouses, and the like, storage racks 10 are fastened through beams 40 to a concrete floor 42. The concrete floor is heated by means of hot glycol which is piped through conduit 46 located within concrete floor 42. Conduit 46 zig-zags throughout the floor in order to maintain a high enough temperature to prevent the concrete slab from heaving and breaking from underslab frost penetration due to freezing. Conduit 46 is connected at appropriate intervals via pipe 48 to glycol main 50 and via pipe 52 to glycol return 54.

Referring to FIG. 8 in particular, it can be seen that located below concrete floor 42, in an access tunnel 56, are conduits 60 for carrying fire-extinguishing liquid, such as water. The water is kept in water main 62 below the surface of the concrete by means of a conventional compressed air system whereby compressed air is kept in the system at the same pressure as the water pressure to depress the water to a certain point, through loss of air in the system, additional compressed air is admitted to the system to make up the loss. The system is sectionalized by a plurality of dry valves 64 permitting water to flow only to that part of the system in which an overheat condition occurs. When such an overheat conditions occurs, as is well-known in the art, the air pressure is released suddenly to permit the water to flow from main 62 to the section of conduit 60 connected to the actuated dry valve 64, via insulated pipe 66 which extends through the concrete floor, via lateral 70, via expansion loop 72, through tubular members 20 and headers 34 from which the water is sprinkled to extinguish the fire. Water in main 62 is kept from freezing because the access tunnel area below the concrete floor 42 is heated.

When an overheat condition occurs, operation of dry valve 64 will actuate valve 76 to permit the heated glycol to flow from glycol main 50, via insulated pipe 78, via lateral glycol feed headers 80 and pipe 82 through a heat exchange conduit 84 located within tubular member 20.

It is preferred that heat exchange conduits 84 be connected in parallel with each other, with the lower portions feeding to lateral glycol feed header 80 and the top of the heat exchange conduits feeding to a lateral glycol return header 90, all of which is shown in schematic form in FIG. 7. Referring to FIG. 7, it can be seen that the glycol is normally pumped from tank 92 by pump 94 and is fed by conduit 50 through a heat exchanger 96 where it is heated and pumped by pump 98 through filter 100 to conduit 102 and under concrete floor 42 to prevent heaving of the concrete slab due to creation of frost under the slab. The purpose of filter 100 is to protect various valves from damage due to foreign matter. The glycol, which has been cooled substantially after passing under a portion of the cold concrete floor, is fed via conduit 54 back to glycol tank 92. In the event of a malfunction in the system, safety conduit 106 including safety valve 108 is provided to form a rapid return path for the glycol.

In the event that an overheat condition is sensed, valve 76 will permit the glycol to flow via feed header 80 and through conduits 84 to glycol return header 90 and back to the glycol tank 92, as indicated by the arrows in FIG. 7. The glycol is heated by heat exchanger 96 to an extent so that when the glycol is flowing through conduits 84 within tubular members 20, the water within the tubular members will not freeze and after the fire has been extinguished, the water can be drained without harm to the system.

A schematic plan view of the positioning of the rack structures is shown in FIG. 4. It can be seen that each of the tubular support members 20 has connected to it a water inlet 110 and a glycol inlet 112. The water inlets are connected to water header 70 and the glycol inlets are connected to glycol header 80. The glycol return header 90 is not shown in FIG. 4.

generator 120 to a hose coupling 124 which is located near the top of conduit 84, and a hose coupling 126 couples the bottom of conduit 84 via condensate return 80 back to the steam generator 120 for recirculation. The steam generator '120 is fed by a suitable heating source 130 and may be actuated in response to activation of dry valve .64 in a similar manner that valve 76 is actuated (opened) in the glycol piping embodiment.

A more detailed diagram of the steam system is shown in FIG. 9. Referring to FIG. 9, it can be seen that the stream is pumped to steam generator 120 by means of pump 132 from collector 134 wherein condensate is collected, deaerated and water is added to compensate for lost water. When valve 76' is actuated due to an overheat condition, the steam flows via conduit 54' to lateral steam feed header 90', through heat exchange conduits (which are connected in parallel), and via lateral steam return header 80 to condensate collector 136. The condensate is pumped by pump 138 through filter 140 to collector 134 for recirculation through the to prevent the concrete slab from heaving, as described above, in connection with the glycol system. Conduit 54' has a back check valve 142 andconnection 144 for providing rapid blow out of condensate in the lines in case of a malfunction, in order to prevent the condensate from freezing in the lines. A safety conduit 106', including safety valve 108, is provided to form a rapid return path for the steam in the event of a malfunction of the system.

It is preferred that most of the pipes described herein, particularly the headers, be insulated in a manner well-known in the art.

Although two illustrative embodiments have been shown and described, it is to be understood that various modifications and substitutions may be made by those skilled in them without departing from the novel spirit and scope of the present invention.

What is claimed is:

1. In a fire protected rack of the type including a plurality of tiers for the storage of articles in a frigid environment and having tubular support means with sup port tiers of the rack and are constructed to convey a Y pressurized fire-extinguishing liquid therethrough, the

improvement comprising, in --'combin ation: a heat exchange conduit located within said tubular support means for conveying a heated fluid; first coupling means located at a lower portion of said heat exchange conduit and extending through said tubular support means for coupling to said heat exchange conduit a first heated fluid transfer pipe, second coupling means located at an upper portion of said heat exchange conduit and extending through said tubular support means for coupling to said heat exchange conduit a second heated fluid transfer pipe; means normally preventing flow of said fire-extinguishing liquid in said tubular support means until an overheat condition is sensed; and valve means providing flow of said heated fluidlin said heat exchange conduit when said fire-extinguishin liquid is flowing in said tubular support means.

2. A construction as described in claim 1, wherein said heated fluid comprises a liquid glycol solution.

3. A construction as described in claim 1, wherein said heated fluid comprises steam, said second coupling means being adapted to couple to said heat exchange conduit said second heatedfluid transfer pipe which is connected to the output of a steam generator for introduction of steam into said upper portion of said heat exchange conduit.

4. A construction as described in claim 3, wherein said first coupling means is adapted to couple to said heat exchange conduit said first heated fluid transfer pipe which is connected to an inlet of said steam generator to recirculate to said steam generator the condensate at said lower portion of said-heat exchange conduit formed from the cooling of the steam introduced into said upper portion of said heat exchange conduit. f g

5. In a fire "protected rack of the type including a plurality of tiers for the storage of articles in a frigid environment and having a plurality of tubular support means which support tiers of the rack and are constructed to convey a pressurized fire-extinguishing liquid therethrough, the improvement comprising, in combination: a-heat exchange conduit located within each said tubular support means for conveying a heated fluid, one end of each heat exchange conduit being connected to a common heated fluid main and the other end of each heat exchange conduit being connected to a common heated fluid return, said common heated fluid main and said common heated fluid return being connected to piping facilities located in a relatively elevated temperature area to provide recirculating heated fluid; heating means for elevating the temperature of said heated fluid to provide a heat medium in heat exchange relationship with any fire-extinguishing liquid in the tubular support means; means normally preventing flow of said fire-extinguishing liquid flow of said heated fluid in said common heated fluid main when said fire-extinguishing liquid is flowing in said tubular support means.

6. A construction as described in claim 5, in which fire-extinguishing liquid flow prevention means comprises a dry-pipe valve wherein the valve is normally held closed by compressed air.

7. A construction as described in claim 5, wherein said fire protected rack is supported on a concrete surface having thereunder said piping facilities, said piping facilities including conduit carrying said heated fluid in heat exchange relationship with said concrete; said valve means being operable to permit flow of said heated fluid to both said undersurface conduit and said heat exchange conduit in said tubular support means.

8. in a fire protected rack of the type including a pin rality of tiers for the storage of articles in a frigid enduit and extending through said tubular support means for coupling to said heat exchange conduit a second heated fluid transfer pipe; said fire protected rack being supported on a concrete surface having thereunder piping facilities including conduit carrying said heated fluid in heat exchange relationship with said concrete; said valve means being operable to permit flow of said heated fluid to both said undersurface conduit and said heat exchange conduit in said tubular support means.

I t l l I

Claims

1. In a fire protected rack of the type including a plurality of tiers for the storage of articles in a frigid environment and having tubular support means with support tiers of the rack and are constructed to convey a pressurized fire-extinguishing liquid therethrough, the improvement comprising, in combination: a heat exchange conduit located within said tubular support means for conveying a heated fluid; first coupling means located at a lower portion of said heat exchange conduit and extending through said tubular support means for coupling to said heat exchange conduit a first heated fluid transfer pipe, second coupling means located at an upper portion of said heat exchange conduit and extending through said tubular support means for coupling to said heat exchange conduit a second heated fluid transfer pipe; means normally preventing flow of said fire-extinguishing liquid in said tubular support means until an overheat condition is sensed; and valve means providing flow of said heated fluid in said heat exchange conduit when said fire-extinguishing liquid is flowing in said tubular support means.

3. A construction as described in claim 1, wherein said heated fluid comprises steam, said second coupling means being adapted to couple to said heat exchange conduit said second heated fluid transfer pipe which is connected to the output of a steam generator for introduction of steam into said upper portion of said heat exchange conduit.

4. A construction as described in claim 3, wherein said first coupling means is adapted to couple to said heat exchange conduit said first heated fluid transfer pipe which is connected to an inlet of said steam generator to recirculate to said steam generator the condensate at said lower portion of said heat exchange conduit formed from the cooling of the steam introduced into said upper portion of said heat exchange conduit.

5. In a fire protected rack of the type including a plurality of tiers for the storage of articles in a frigid environment and having a plurality of tubular support means which support tiers of the rack and are constructed to convey a pressurized fire-extinguishing liquid therethrough, the improvement comprising, in combination: a heat exchange conduit located within each said tubular support means for conveying a heated fluid, one end of each heat exchange conduit being connected to a common heated fluid main and the other end of each heat exchange conduit being connected to a common heated fluid return, said common heated fluid main and said common heated fluid return being connected to piping facilities located in a relatively elevated temperature area to provide recirculating heated fluid; heating means for elevating the temperature of said heated fluid to provide a heat medium in heat exchange relationship with any fire-extinguishiNg liquid in the tubular support means; means normally preventing flow of said fire-extinguishing liquid in said tubular support means until an overheat condition is sensed; and valve means automatically providing flow of said heated fluid in said common heated fluid main when said fire-extinguishing liquid is flowing in said tubular support means.

8. In a fire protected rack of the type including a plurality of tiers for the storage of articles in a frigid environment and having tubular support means which support tiers of the rack and are constructed to convey a pressurized fire-extinguishing liquid therethrough, the improvement comprising, in combination: a heat exchange conduit located within said tubular support means for conveying a heated fluid; first coupling means located at a lower portion of said heat exchange conduit and extending through said tubular support means for coupling to said heat exchange conduit a first heated fluid transfer pipe, second coupling means located at an upper portion of said heat exchange conduit and extending through said tubular support means for coupling to said heat exchange conduit a second heated fluid transfer pipe; said fire protected rack being supported on a concrete surface having thereunder piping facilities including conduit carrying said heated fluid in heat exchange relationship with said concrete; said valve means being operable to permit flow of said heated fluid to both said undersurface conduit and said heat exchange conduit in said tubular support means.