Patent Publication Number: US-2012027520-A1

Title: Reinforced Dikes For Damming Or Diverting Liquids

Description:
CROSS REFERENCE TO RELATED APPLICATION 
     This application claims the benefit of U.S. Provisional Patent Application Ser. No. 61/297,906 filed Jan. 25, 2010, which is fully incorporated herein by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     This invention is related to reinforced devices for controlling fluid flow and, more particularly, to portable dikes for damming and diverting liquids. 
     Removable liquid blocking devices for use on surfaces, such as building floors, are well-known in the art. See, for example, U.S. Pat. Nos. 4,031,676; 4,981,391 and 5,059,065. However, with the advent of strict environmental regulations, there is an increasing need for readily accessible damming devices which can be placed on a spill surface for immediate control of hazardous liquids. Furthermore, it is desired that the devices be readily adaptable to enclose areas of varying shapes and sizes, with minimal effort and expense. 
     U.S. Pat. No. 4,031,676 discloses a rubber water blocking device having a bottom surface with a plurality of recessed disc portions which define suction cups. The bottom is engaged on smooth surfaces to form a semi-permanent dam structure. The device may be provided in straight sections and curved sections, with the sections interlocked by a tongue and groove arrangement. This device appears unduly expensive to manufacture as any mold which forms the device would have to provide several suction cups on the bottom surface. The device also suffers from reduced adaptability because it is provided in sections of predetermined length which are not easily adapted on site to conform to various sized spill areas. 
     U.S. Pat. No. 4,981,391 discloses an inflatable, portable dam apparatus having a tubular structure and a bottom sheet of flexible material. Inflation of the dam is unduly time consuming, especially in cases where immediate, on-site liquid control is the desired object. 
     Similarly, U.S. Pat. No. 5,059,065 discloses a fluid-filled damming structure having a coupling sleeve arrangement for interconnecting and receiving adjacent ends of the damming structures. 
     U.S. Pat. No. 3,847,722 discloses a permeable, laminated web impregnated with a urethane prepolymer to stop water leaks in small holes or crevices. The prepolymer reacts with water to form a swollen, adherent hydrogel. However, the web does not have substantial thickness, so it cannot be placed on a level spill surface for controlling or containing liquids. A permeable filler material, such as wood chips, may be placed inside the web, but this is impractical for on-site spill control. 
     U.S. Pat. No. 5,236,281 discloses a non-permeable urethane dike, preferably triangular in shape. The dike forms an effective seal but tends to heavy and prone to UV degradation. Reducing the mass of the dike has a negative effect on adhesion since weight is required to form the seal. Increasing the tackiness, in order to reduce the weight, results in tearing during removal. 
     Therefore, it is an object of the present invention to provide a device for damming and diverting liquids on spill surfaces, such as building floors, that is lighter weight, conformable and tear resistant. It is a further object to provide a pliable device which may be easily conformed and tailored to meet a variety of damming configurations. It is a still further object to provide a device which is readily adherent to the spill surface. Finally, it is an object to provide a device which comports with the above objectives, but which may be quickly employed on site for emergency spill control, and further which is inexpensive and simple to manufacture. 
     SUMMARY OF THE INVENTION 
     The invention is a device for damming and diverting liquids on a spill surface having an elongated, pliable dike with a first end, a second end, and a tacky exposed surface. Variations in construction provide for improved tear resistance, UV resistance and chemical compatibility. The exposed surface adheres to a spill surface to prevent flow of liquid past the dike and is preferably smooth. 
     The device also includes methods for joining the end of one device to another device to increase the effective length of the dike. These methods include various geometric shapes that increase the effective length of the joint area. Each end of the dike may have a tacky abutment surface, so that when adjacent ends of successive dikes are engaged, they will adhere to one another to form a joint. A joint housing whose internal dimensions conform to the external dimensions of the dike may be used to overlap the joint to help seal the joint. The ends of the dike may also comprise interlocking configurations, such as dovetails or male/female connections. 
     The invention also includes a method for creating a liquid control zone on a spill surface, utilizing the dike described above. The method may include severing a portion of the dike to form specific liquid control areas. 
     The invention may be utilized both to contain liquid and to divert liquid flow. The dike is readily pliable to conform to various damming configurations. Portions of the dike may be severed on site by the user, without special tools, to tailor the dike for specific damming needs. All exposed surfaces on the dike can be inherently tacky. However, some variations may have a durable covering on one or more surface. 
     These and other aspects of the present invention will be more fully understood following a review of this specification and drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a cut-away view of a curved dike with a durable covering on one side, in accordance with an aspect of the invention. 
         FIG. 2  is a cut-away view of a curved dike with an extended durable covering on one side, in accordance with an aspect of the invention. 
         FIG. 3  is a cut-away view of an angular dike with the durable covering on top, in accordance with an aspect of the invention. 
         FIG. 4  is a cross section of a rounded dike that has reinforcing fibers dispersed within the dike, in accordance with an aspect of the invention. 
         FIG. 5  is a cross section of a rounded dike with a durable covering, in accordance with an aspect of the invention. 
         FIG. 6  is a cross section of a rounded dike with two different durometer tacky layers and a horizontal reinforcing layer, in accordance with an aspect of the invention. 
         FIG. 7  is a cross section of a rounded dike that has a vertical reinforcing layer inserted along the length of the dike, in accordance with an aspect of the invention. 
         FIG. 8  is a cross section of a rounded dike that has an inserted rope or wire like material inserted along the length of the dike, in accordance with an aspect of the invention. 
         FIG. 9  shows a perspective view of rounded dike with male and female ends that resists separation when two or more dikes are connected, in accordance with an aspect of the invention. 
     
    
    
     DETAILED DESCRIPTION 
       FIGS. 1 and 2  show a curved dike  10  having a pliable, tacky body  12  and a durable covering comprised of low-density bonding layer  14  and at least one protective layer  16 . The pliable, tacky body  12  is made from a soft, yet resilient material, such as polyurethane so as to provide an inherently tacky, resilient material. The durable covering comprised of low-density bonding layer  14  provides strengthening to the body  12 , but it will be appreciated that the body  12  can be provided without the durable covering comprised of low-density bonding layer  14  or other means for strengthening may be used as will be described herein and shown in other embodiments of the invention. 
     As shown in  FIG. 2 , multiple protective layers  16  can be used, as well as metal reinforcement  18  therebetween. The bottom of the dike is generally an exposed surface  19  that may be, for example, substantially smooth. A low-density bonding layer  14  is used to join the protective layers  16  to the pliable, tacky body  12 . 
     As used herein, the term “low-density bonding layer” means a deep pile or lofty material having at least one surface comprising entanglement fibers that extend from the layer to provide additional surface area and attachment sites for the protective layer  16  and/or pliable, tacky sealing body  12 . The low-density bonding layer  14  has a density that is typically less than 0.26 ounces per cubic inch, preferably from 0.02 to 0.1 ounces per cubic inch. The low-density bonding layer  14  has a typical thickness of at least 0.01 inch, for example, from 0.02 to 0.25 inch. In one embodiment, the thickness is from 0.04 to 0.06 inch. The low-density bonding layer  14  typically has a weight per area of less than 20 ounces per square yard, for example, from 1 to 10 ounces per square yard. The low-density bonding layer  14  provides secure and permanent attachment between the protective layers  16  and the pliable, tacky sealing body  12 . 
     The protective layer  16  is liquid impermeable and is made of a flexible and durable material. The protective layer  16  can have a tensile strength at least 25 percent higher than the tensile strength of the pliable, tacky body  12 . The protective layer  16  can comprise any suitable material such as natural rubber, synthetic rubber, EPDM rubber, nitrile rubber or plastics such as thermoplastic olefin, polyvinyl chloride, chlorosulfonated polyethylene and the like. In one embodiment, protective layer  16  may be a composite material. Examples of composite materials include rubber laminated to plastic film, plastic film laminated to mesh, rubber laminated to mesh and combinations thereof. The thickness of protective layer  16  typically ranges from 0.002 to 0.25 inch. 
     Metal reinforcement  18  can be used to provide structural support to the extended vertical sections of the durable cover. The metal reinforcement  18  in the preferred embodiment is flattened expanded metal. Other options beyond expanded metal include perforated metal, wire screen and wire cloth. Expanded metal is typically less expensive than perforated metal, and the associated alloys tend to more malleable. Wire screen and cloth tend to have an undulating surface due to the associated weaving and can require a thicker plastic to cover and fuse into the open areas. The undulating surface of standard expanded metal is what leads to the preference toward the flattened version. 
       FIG. 3  shows an angular dike  20 . The angular dike  20  may take many shapes, but preferably it is an rectangle, square, trapezoid or triangle on the ends. The angular dikes  20  described herein only have one face laminated to a durable covering. Multiple faces are conceived in this invention but greatly reduce the bending capability of the dike and greatly increases the radius used to make curves. In any case, the bottom surface of the dike  20  is inherently tacky. 
       FIG. 4  shows a rounded dike  30  that is reinforced with fibers  22 . The fibers provide an entanglement that directs removal stress on the fibers instead of the pliable, tacky polymer  12 . 
       FIG. 5  shows a rounded dike  30  with a durable covering comprised of low-density bonding layer  14  and at least one protective layer  16 . The bonding layer  14  is not bonded to the tacky layer  12  at the outermost edges so that the durable cover does not interfere with the sealing surface. 
       FIG. 6  is a cross section of a rounded dike  30  with softer sealing surface on the bottom  24 , a harder more tear resistant top surface  26  and an inserted horizontal layer of tear resistent material  28  along the length of the dike. 
       FIG. 7  is a cross section of a rounded dike  30  that has an internal strengthening member such as a vertical reinforcing layer  32  inserted along the length of the pliable, tacky body  12 . 
       FIG. 8  is a cross section of a rounded dike  30  that has an internal strengthening member such as an inserted rope  34  or wire like material inserted along the length of the pliable, tacky body  12 . 
       FIG. 9  illustrates that the ends of the dike can be formed with male joints  36  and female joints  38  such as a puzzle end, dovetail, keystone or other shapes that resist separation when two or more dikes are connected. The ends could also be cut on an angle or have other non locking geometries. 
     The reinforced dikes are made from polyurethane or other flexible materials such as polyvinyl chloride. Particularly, a mixture of various polymers are poured into a mold and allowed to cure. The liquid is mixed and cured in a manner which gives a moderate degree of inherent tackiness. The molding and curing process creates a substantially smooth bottom surface, which may contain minor undulations. As mentioned above, the polyurethane dike is soft, yet resilient, and thus may be easily severed by a user with a knife. Surfaces on the dike which are exposed when a portion of the dike is severed are also inherently tacky. 
     In use, the dikes can be shipped and stored in coiled, five-foot or ten-foot sections either wrapped in plastic film or packed in a wax-lined box. The coils are separated by either the plastic film or cardboard sheets to preserve the tackiness. 
     Further advantages are derived from use of the reinforced dike to dam or divert liquids as follows. 
     The reinforced dike enables high-adhesion formulations of the pliable, tacky body. Without durable covering, the pliable, tacky body is limited in adhesion. If the adhesion is too strong, a dike that is not reinforced can tear during removal. The methods shown in the various figures allow for increased tensile and tear strength of the dike. In addition, the durable coverings shown also provide puncture and tear resistance. Since the adhesion level can now be increased, the mass of the reinforced can be reduced. Excessive weight is no longer needed to help form the seal. 
     The durable covering shown in  FIGS. 1 ,  2 ,  3 ,  5  and  9  can improve the UV and chemical resistance of the dike  10 . Urethane has a limited life when exposed to acids and direct sunlight. The protective layers  16  can be selected to improve these characteristics. 
     Whereas particular embodiments of this invention have been described above for purposes of illustration, it will be evident to those skilled in the art that numerous variations of the details of the present invention may be made without departing from the invention as defined in the appended claims.