Abstract:
Methods and systems for plugging a hole are described. A plug may comprise a substantially tubular member having a proximal end and a distal end interconnected by a side wall, the side wall having an inward facing surface and an outward facing surface, at least the outward facing surface being substantially conformable, an adhesive disposed on the outward facing surface, a fire-resistant ring disposed substantially at one of the ends of the tubular member, and a thread disposed along the inward facing surface, the thread adapted to receive a cover.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
   This application claims the benefit of the following provisional application, which is hereby incorporated by reference in its entirety: U.S. Provisional Application No. 60/900,609 filed Feb. 9, 2007. 

   BACKGROUND 
   1. Field 
   This invention generally relates to plugging penetrations in concrete building floors, the penetrations being intended typically for passage of pipes, utilities, and the like. 
   2. Description of the Related Art 
   Penetrations, or openings, are commonly drilled in concrete slabs of buildings under construction in order to pass pipes, utilities, and other things through the concrete slab (e.g., a floor under construction) from one level of the buildings to another. The process of core drilling a concrete slab and setting plumbing, fire control plumbing pipes and electrical conduits and fire-proofing the installation on construction job sites is a multi-step process that is labor-intensive. The coring process in a large scale construction project creates many (sometimes hundreds or thousands of) slab bore holes that must be temporarily covered until the pipe installation is complete and the final plugging and fireproof caulking is finished. 
   Concrete construction utility passage holes are usually bored oversize (by a factor of 2 to 4) beyond what is necessary for passage of a particular pipe or utility. After completion of the slab boring operation with a diamond coring tool, building codes call for a temporary closure of the hole for safety reasons. For example, tools and debris can drop from one floor down onto people and things on lower floors through the hole openings causing injury and economic loss. Additionally, the holes are plugged to prevent people walking on a floor with openings in the floor from falling through or having their feet accidentally caught in the openings. 
   A common practice to plug construction holes in concrete floors is to use a specially-fabricated wooden hole cover or plug consisting of a shaped (e.g., rectilinear) piece of plywood backed by “2-by-4” structural wood cross bracing that is configured to fit the hole cover so as not to be dislodged by normal construction activities such as walking over the hole cover. The fabrication of thousands of wood cover plates to cover and protect all the core drilled openings in a building under construction is a time consuming and costly operation. 
   While specially-fabricated conventional wooden hole covers offer some protection from inadvertent accidents by intrusion of people and objects into the exposed holes they do not provide protection from water penetration and leakage, and provide little fire protection. Water from rain or other operations can run down through the holes from one floor to those below it and cause damage or pooling in the lower floors. In a large construction job site, water leakage through floor openings can be a significant problem and a cause large financial losses, e.g., if a storm inundates the site and the water finds its way down many floors through the unprotected holes into areas where finishes have already been applied. Even flooding of an unfinished basement is costly where pumping is required to make the space habitable for continued construction work and to protect the building&#39;s foundation. 
   Pipe fitters tend to work their way through a construction project gradually installing the piping and finalizing the penetrations in the floors. The temporary hole covers are removed and discarded and after the pipes are inserted through the holes, the perimeter around the pipe is stuffed with mineral wool to block the hole and provide a backing for fire-retardant caulking, usually required by building codes, which is hand applied to the top inch or so around the pipe, sealing it to the concrete of the side-wall of the holes. These steps are labor-intensive and thus very expensive. 
   In light of the above discussion, there is a need for an apparatus and a system that solves most or all of the problems of the current procedure for hole drilling and pipe installation and sealing of the penetrations. 
   SUMMARY 
   The present invention provides a method and system for securing a cored penetration in a concrete slab. The method and system may include providing a concrete hole plug. The concrete hole may include a lower hole plug and a top cover securely attached to the lower hole plug for sealing the hole. The lower hole plug may include an adhesive on the outside surface for adhering to the concrete wall of the hole and a well for holding fire-resistant sealant to form a perimeter seal on installed pipe. The top cover may include one or more securing mechanism for attaching the top cover to the hole plug. Further, the method and system may include exposing the adhesive on the outside surface of the lower hole plug, disposing the concrete hole plug into a hole bored in a concrete slab and securing the top cover to the lower hole plug using the securing mechanism. 
   In embodiments, the method and system may include tightening of the concrete hole plug is facilitated by a partial turn large thread member to secure the upper and lower portions of the plug. In embodiments, the method and system may include a secondary attachment of the top cover to the lower hole plug to prevent loss of the top cover when the plug is opened. In embodiments, the method and system may include circumferential fins disposed on the lower hole plug that deform when the plug is pushed into the hole and lock the lower hole plug to the concrete. 
   In embodiments, the securing mechanism may comprise the top cover molded with an integral nut protrusion on the top surface that engages a wrench. In embodiments, the securing mechanism may comprise a threaded attachment. In embodiments, the securing mechanism of the top cover may be substantially below the concrete surface. 
   In embodiments, tightening the nut may expand the hole plug against the wall of the hole to create a watertight seal and press the adhesive securely against the wall of the concrete hole to achieve a good bond. 
   In embodiments, the removal of the concrete hole plug may leave behind an orifice that accommodates the intended pipe installation or may leave behind a molded ring of fire-resistant sealant that is conformable with pressure. In embodiments, the lower hole plug may comprise a deformable elastomeric material. In embodiments, the lower hole plug may be pressurized by the tapered thread and may be expanded against the side-wall of the floor penetration creating a water tight seal. 
   In embodiments, the inside of the hole plug may comprise threads for adapting to a pipe diameter. In embodiments, stress rings in the lower wall of the hole plug may facilitate creating the appropriate hole diameter to accommodate a pipe. In embodiments, the pull tabs may facilitate creating the appropriate hole diameter to accommodate a pipe. In embodiments, the lower wall of the hole plug may be removed to accommodate a pipe. 
   In embodiments, the top cover may be rigid, compliant or elastomeric and may be substantially flush with the upper concrete surface. In embodiments, the top cover may comprise flexible gasket ridges that deform to provide a watertight and fire retardant seal against the wall of the hole. In embodiments, the top cover may comprise a lock to prevent unauthorized opening or removal of the concrete hole plug. 
   In embodiments, the perimeter seal may be tamped into a fire retardant seal around the installed pipe. 
   In embodiments, the adhesive may be microencapsulated, activate-able, or peel-away. 

   
     BRIEF DESCRIPTION OF THE FIGURES 
     The invention and the following detailed description of certain embodiments thereof may be understood by reference to the following figures: 
       FIG. 1  depicts a hole drilling and pipe installation process through a concrete floor slab. 
       FIGS. 2A and 2B  depict an exemplary deformable concrete hole plug according to an embodiment of the present invention. 
       FIG. 3  depicts exemplary steps of securing a deformable concrete hole plug according to an embodiment of the present invention. 
       FIGS. 4A and 4B  depict an exemplary deformable concrete hole plug according to another embodiment of the present invention. 
       FIG. 5  depicts exemplary steps of securing a deformable concrete hole plug according to an embodiment of the present invention. 
       FIG. 6  depicts an exemplary concrete hole plug in accordance with an embodiment of the present invention. 
   

   DETAILED DESCRIPTION 
   While the specification concludes with the claims defining the features of the invention that are regarded as novel, it is believed that the invention will be better understood from a consideration of the following description in conjunction with the drawings figures, in which like reference numerals are carried forward. 
   As required, detailed embodiments of the present invention are disclosed herein; however, it is to be understood that the disclosed embodiments are merely exemplary of the invention, which can be embodied in various forms. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the present invention in virtually any appropriately detailed structure. Further, the terms and phrases used herein are not intended to be limiting but rather to provide an understandable description of the invention. 
   The terms “a” or “an”, as used herein, are defined as one or more than one. The term “another”, as used herein, is defined as at least a second or more. The terms “including” and/or “having” as used herein, are defined as comprising (i.e. open transition). The term “coupled” or “operatively coupled” as used herein, is defined as connected, although not necessarily directly, and not necessarily mechanically. 
     FIG. 1  depicts a hole drilling and pipe installation process through a concrete floor slab  102 . The sequence of steps, as shown in  FIG. 1 , are presently used in the construction industry to core drill through the concrete floor slab  102  in a construction project, and fitting and fire-proofing the plumbing pipes and electrical conduit installed on the project. 
   Pipe fitting on a construction project may begin with drilling out a core  110  from the concrete floor slab  102 , as shown in  FIG. 1A . During this step, a mechanical construction crew may drill out the core  110  required by the plumbing design. This is accomplished with a special machine utilizing a diamond coring bit  104  that accurately and repeatedly cores holes that are normally in one inch increments, i.e., 2″, 3″, 4″, 5″ etc. The machine will cut through not only the concrete but steel reinforcing and corrugated steel floor pans  108  that normally support the poured concrete slab and the core  110  falls to the floor below. 
   Referring to  FIG. 1B , after the holes are drilled, the hole may be covered to protect people from stepping into the holes and from tools or other objects from falling through the hole and injuring someone beneath. Typically, the job site carpenters fabricate individual plywood and lumber hole covers  112  by hand, sometimes for as many as tens of thousands of holes on a larger job site. These covers stay in place, sometimes for as long as ten months, until the pipe fitters are ready to install the pipes through the hole. 
   When the pipe fitters are ready to install a pipe  114  through the hole, the hole cover  112  is removed and discarded. Following this, the pipe  114  is positioned and connected to the adjoining fittings required for the plumbing design, as shown in  FIG. 1C . Typically, the hole is several pipe diameters wide to provide good clearance around the pipe. 
   Referring to  FIG. 1D , the building code often requires fire retardant caulking to be placed in the perimeter hole around the pipe  114  in the clearance area so that in the event of a fire, the fire doesn&#39;t spread between floors through the open floor penetrations. To support the caulking that is normally an inch or so thick, the pipe fitters pack mineral wool  118  around the perimeter of the pipe  114 . 
   The mineral wool  118  may create a toroidal (donut shaped) mass around the pipe  114 , as shown in  FIG. 1E . This may seal it against the concrete wall of the hole to permit application of the fire retardant caulking  120  that is hand-applied with a caulking gun. The caulking may be one to two inches thick. 
     FIGS. 2A and 2B  depict an exemplary deformable concrete hole plug  202  according to an embodiment of the present invention. The deformable concrete hole plug  202  may include a compliant/elastomeric top cover  204  with flexible gasket ridges that may deform to provide a water seal against the wall of the hole. Further, the elastomeric top cover  204  may be molded with an integral standard size hex nut protrusion  208 , or any other fastening device, on the top surface that may engage a standard wrench. The elastomeric top cover  204  may be attached to the lower conformable hole plug  210  by a coarse thread  214 , as shown in  FIG. 2B . The elastomeric top cover  204  and the lower conformable hole plug  210  may be screwed together by the hex nut  208 . The lower conformable hole plug  210  may have a microencapsulated adhesive or a peel away protected adhesive on the outside surface that may contact the concrete side-wall of the penetration. Sandwiched between the lower conformable hole plug  210  and the elastomeric top cover  204  and affixed  218  to the concrete hole plug  202  may be a molded ring of fire retardant sealant  212  that is conformable with pressure. 
     FIG. 3  depicts exemplary steps of securing the deformable concrete hole plug  202  according to an embodiment of the present invention. The deformable concrete hole plug  202  may provide safety protection for a cored hole in a concrete slab. Further, the deformable concrete hole plug  202  may seal the penetration in a watertight manner with the help of the elastomeric top cover  204 . 
   Before inserting the deformable concrete hole plug  202  in the hole, the peel away protected adhesive  308  on the outer surface  302  of the lower conformable hole plug  210  may be activated by peeling the peel away protection layer. This may activate a time delay adhesive  308  or simply expose an adhesive. Following this, the concrete hole plug  202  may be positioned into the hole and pressure  304  may be applied to push the lower conformable hole plug  210  into the hole and then engage the elastomeric top cover  204 , deforming the thin flexible gasket ridges against the wall of the hole to create a water tight and fire-retardant seal. In embodiments, the pressure  304  may be applied by pressing the concrete hole plug  202  with a foot, as shown in  FIG. 3A . However, in other embodiments, the concrete hole plug  202  may be inserted in the hole by applying pressure  304  using a hammer, a weight or other such means. 
   Pressure  304  is applied on the concrete hole plug  202  until the point the flange of the elastomeric top cover  204  is substantially flush with the upper concrete floor surface, as shown in  FIG. 3B . Now, the flange being substantially flush with the upper concrete floor surface and the hex nut  208  or other fastener being below the upper surface, the adhesive  308  may act over time to bond the concrete hole plug  202  to the concrete wall of the hole. 
   After the concrete hole plug  202  is bonded with the wall of the hole, the concrete hole plug  202  may be dismantled to remove the elastomeric top cover  204  from the lower conformable hole plug  210  using a wrench or other tool, as shown in  FIG. 3C . Following this, a pipe may be inserted in the hole and may be made to pass through the lower conformable hole plug  210 . The coarse thread  214  of the lower conformable hole plug  210  may adapt to the diameter of the pipe to provide a desirable fit. In embodiments, the hole in the preformed ring of the fire retardant sealant  212  may be larger than the diameter of the pipe and may be tamped into firm contact with the pipe. 
     FIGS. 4A and 4B  depict an exemplary deformable concrete hole plug  402  according to another embodiment of the present invention. The deformable concrete hole plug  402  may include a rigid top cover  404 . Further, the rigid top cover  404  may be molded with an integral standard size hex nut protrusion  408 , or other fastener, on the top surface that may engage a standard wrench. The rigid top cover  404  may be attached to a lower conformable hole plug  410  by a coarse tapered thread  414 , as shown in  FIG. 4B . The rigid top cover  404  and the lower conformable hole plug  410  may be screwed together by the hex nut  408 , or other fastener, on the top cover. The lower conformable hole plug  410  may be pressurized by the tapered thread  414  and expand against the wall of the hole creating a water tight seal. The lower conformable hole plug  410  may have a microencapsulated adhesive or a peel away protected adhesive on the outside surface that may contact the concrete wall of the hole. Sandwiched between the lower conformable hole plug  410  and the rigid top cover  404  and affixed  418  to the hole plug may be a molded ring of fire retardant sealant  412  that is conformable with pressure. 
     FIG. 5  depicts exemplary steps of securing the deformable concrete hole plug  402  according to an embodiment of the present invention. The deformable concrete hole plug  402  may provide safety protection for a cored hole in a concrete slab per code requirements during the duration of its dormancy (non-use). Further, the deformable concrete hole plug  402  may seal that hole in a water tight manner using an expandable compliant plug technology for that period while leaving behind upon removal the lower conformable hole plug  410  that accommodates the intended pipe installation and sets a pre-molded fire-resistant caulk pipe perimeter seal, that may be required by code, that can be tamped into a fire retardant seal around the installed pipe. 
   The peel away protected adhesive  508  on the outer surface of the lower conformable hole plug  410  may be exposed or activated by peeling the peel away protection layer. Further, the lower conformable hole plug  410  may be positioned into the hole and a wrench  504  may be used to screw the rigid top cover  404  into the lower conformable hole plug  410 , as shown in  FIG. 5A . As the rigid top cover  404  is screwed to the lower conformable hole plug  410 , the lower conformable hole plug  410  expands against the wall of the hole. As a result of this, the adhesive  508  may be pressed against the wall to achieve a good bond. This also ensures a water tight seal between the wall of the hole and the lower conformable hole plug  410 . 
   When the rigid top cover  404  has been fully fastened with the lower conformable hole plug  410 , the lower conformable hole plug  410  may take an orientation as shown in  FIG. 5B . In this orientation, the flange of the rigid top cover  404  may be substantially flush with the concrete floor and the nut  408  or other fastener may be below that surface. Further, the lower conformable hole plug  410  may be expanded  510  against the wall of the hole creating a water tight seal. Also, the pressure created because of the expansion of the lower conformable hole plug  410  helps in achieving a good bond between the wall of the hole and the lower conformable hole plug  410 . 
   Once the lower conformable hole plug  410  is bonded with the wall of the hole, the rigid top cover  404  may be dismantled from the lower conformable hole plug  410  using the wrench  504 . Dismantling the rigid top cover  404  and the lower conformable hole plug  410  may leave behind the lower conformable hole plug  410  adhered to the wall of the hole, as shown in  FIG. 5C . Following this, a pipe may be inserted in the hole and may be made to pass through the lower conformable hole plug  410 . The coarse tapered thread  414  of the lower conformable hole plug  210  may adapt to the diameter of the pipe to provide a desirable fit. In embodiments, the hole in the preformed ring of the fire retardant sealant  412  may be larger than the diameter of the pipe and may be tamped into firm contact with the pipe. 
   It may be appreciated by those skilled in the art that various modifications to the design of the concrete hole plug  402  may be possible without deviating from the scope of the invention. For example, in embodiments, the adhesive  508  on the outside surface of the lower conformable plug hole  410  may be replaced by any other means for bonding the lower conformable plug hole  410  with the wall of the hole. One such modification has been described in conjunction with  FIG. 6 . 
     FIG. 6  depicts an exemplary concrete hole plug  602  in accordance with an embodiment of the present invention. The concrete hole plug  602  may include an upper portion  604  and a lower portion  608 . The upper portion  604  and the lower portion  608  may be attached by a coarse thread  624  in a similar manner as described in other embodiments. The coarse thread  624  may be a partial thread, i.e. a quarter thread or a half thread. 
   The lower portion  608  may include multiple fins  610  along the circumference of an outer surface  612  of the lower portion  608 . Now, when the concrete hole plug  602  is pushed into the hole, these fins  610  may deform and may provide the necessary bonding/locking between the lower portion  608  and the wall of the hole. 
   In embodiments, a lower wall  614  of the lower portion  608  may include creases or dents or mechanically stamped thin outlines  618 . These creases or dents or mechanically stamped thin outlines  618  may act as stress lines and may facilitate tear-out of the lower wall  614  to accommodate a pipe during fittings. Now, when the pipe is to be fitted in the hole and is made to pass through the lower portion  608  of the concrete hole plug  602 , a hole of corresponding diameter may be punched or peeled out from the lower wall  614 . For example, in case of a pipe of 3 inch diameter being inserted in the hole, a user may punch out a circular portion of 3 inch diameter from the lower wall  614 . The circular portion may be easily punched out because of the presence of the creases or dents or mechanically stamped thin outlines  618 . When the user applies force to tear the circular portion using a pull tab  620 , a stress may be accumulated along these creases  618 . As a result of this stress, the circular portion may be punched out with ease. 
   In embodiments, the lower wall  614  may be fabricated from rubber, plastic, thin metal material or the like. Further, the lower portion  608  may provide a well  622 . The well  622  may hold fire-resistant sealant to form a perimeter seal on the installed pipe. 
   The specific embodiments provided and illustrated herein are meant only by way of description and are not intended to be comprehensive or exhaustive of all possible embodiments thereof. For example, not only can the covers of the present plugs include standard size nuts for operation with standard tools, but may include non-standard or other securing mechanisms which in some cases prevent unauthorized opening of the penetrations and securing removal or loss of the plugs. For example, hex nuts (or other configurations of nuts) can be used so that only a specialized custom tool can operate the hole plug. Also, Allen wrench operation using standard or non-standard wrench sizes is possible. In addition, the use of other materials in the fabrication of the present devices is possible. In addition, the frictional surfaces may be provided with special surface features to enhance the operation of the plugs. 
   The plugs can furthermore be easily constructed to be color-coded or include written symbols, words, or other indicia of their use (e.g., red plugs designating fuel line penetrations). Additionally, the plugs can include auxiliary attachments and features to enhance their operation. For example, including a lanyard or cord or chain that is attached at one end to the upper portion of the plug and the other end being attached to another portion such as a lower portion of the plug. The lanyard being of finite length, such as eight inches long, that prevent the loss of a cover for a temporarily-opened plug device where the cover portion thereof might be discarded or swept away or kicked away accidentally if left lying on the floor. 
   Other embodiments and modifications of the present disclosure are comprehended within the scope of the present invention and disclosure and can be appreciated by those skilled in the art. 
   Many other systems, methods, objects, features, and advantages of the present invention will be appreciated. All such systems, methods, object, features, and advantages are within the scope of the present disclosure. 
   While the invention has been disclosed in connection with certain preferred embodiments, those of ordinary skill in the art may recognize other embodiments, and all such variations, modifications, and substitutions may be intended to fall within the scope of this disclosure. Thus, the invention may be to be understood in the broadest sense allowable by law.