Crib Bag

Abstract

A crib bag is disclosed that includes a one-way fill valve, such as a duck bill valve, and a vent positioned at the top of the crib bag to allow venting of air from the crib bag when the bag is filled with cement compound and as the cement compound solidifies. When the mining crib bag is filled with cement compound, the one-way fill valve and the top vent prevent spillovers and associated hazards.

Description

RELATED APPLICATION

This application claims the benefit of U.S. Provisional Application Serial No. 61/560,511 filed on Nov. 16, 2011, the entire disclosure of which is expressly incorporated by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a crib bag for forming roof support columns for underground mining operations.

2. Related Art

Crib bags are known in the art for forming roof supports in underground mines. Crib bags are positioned at desired locations in an underground mine, and are filled while in the extended configuration with a fluid load-bearing material, such as a two-part cementation compound, which solidifies until the crib bag creates a column extending from the floor to the ceiling of the mine. A major safety concern with current crib bags is that the cement used to fill the bags is usually caustic and can be dangerous if it spills or leaks during the filling process.

Accordingly, what would be desirable, but has not yet been provided, is a crib bag which addresses the foregoing limitations of existing crib bags.

SUMMARY OF THE INVENTION

A crib bag is disclosed that includes a one-way fill valve, such as a duck bill valve, and a vent positioned at the top of the crib bag to allow venting of air from the crib bag when the bag is filled with a cement compound and when the cement compound solidifies. When the crib bag is filled with cement compound, the one-way fill valve and the vent prevent spillovers and hazards that may be associated therewith.

In one embodiment, a crib bag includes a cylindrical side wall attached to a bottom wall and a top wall. A vent is provided at the top wall, and a one-way valve is provided at an upper portion of the cylindrical side wall.

In another embodiment, a method for forming a roof support column is provided. The method includes the steps of suspending a crib bag at a location, filling a chamber of a crib bag with a load-bearing material through a one-way valve, allowing air to vent from the crib bag through a vent as the crib bag is being filled, and closing the vent when the crib bag is completely filled.

Additionally, in another embodiment, a crib bag includes a cylindrical side wall attached to a bottom wall and a top wall, and a chamber. An aperture is formed in a top wall to allow venting from the chamber. A cover is provided, the cover having a greater diameter than the aperture, the cover closing the aperture after the cylindrical side wall is filled with a load-bearing material.

BRIEF DESCRIPTION OF THE DRAWINGS

The foregoing features of the invention will be apparent from the following Detailed Description of the Invention, taken in connection with the accompanying drawings, in which:

FIG. 1 is a side view of the crib bag according to the present disclosure;

FIG. 2 is a perspective view of the crib bag shown in FIG. 1;

FIG. 3 is a top view of the crib bag shown in FIG. 1;

FIG. 4 is a side view of a lifting lug for supporting the crib bag shown in FIG. 1;

FIG. 5 is a partial sectional view taken along line B-B of FIG. 1;

FIG. 6 is a partial internal view taken at location “C” of FIG. 1;

FIG. 7 is a partial enlarged view taken at location “D” of FIG. 1;

FIG. 8 is a perspective view of a one-way valve utilized by the present invention; and

FIG. 9 is a sectional view of the one-way valve shown in FIG. 8 and taken along the line A-A of FIG. 1.

DETAILED DESCRIPTION OF THE INVENTION

The present invention relates to a crib bag for forming roof support columns in underground mines.

FIG. 1 is a side view of the crib bag 10 of the present invention in an extended configuration. The crib bag 10 comprises a form that receives cement/cement compound, and includes a side wall 12 defining a cylindrical chamber, and a helical rib 14 extending from proximal a top wall 16 of the crib bag 10 to proximal a bottom wall 18. The side wall 12 can be made of a durable fabric material, such as a polymeric material, e.g., a heavy duty polyvinyl chloride (PVC) laminated polyester. The rib 14 can be made of a rigid or semi-rigid material, such as metal wire, e.g., a steel wire. The crib bag 10 can be collapsed for easy storage and/or transportation. The crib bag 10 could also include one or more fabric strips 20a, 20b, which can be attached at upper ends to the bag 10 and can be used to strap the ends of the crib bag 10 together when the crib bag 10 is collapsed (e.g., when transporting and/or storing the crib bag 10 before use). The crib bag 10 could also include a plurality of lifting lugs 22a, 22b with grommets 24a, 24b that can attach to corresponding roof bolts for suspending the crib bag 10 at a desired location in a mine. It is noted that any desired number of lugs could be provided (e.g., six lugs could be provided). A valve 26 is provided at an upper end of the crib bag 10 for introducing a cement/cement compound into the crib bag 10.

The top wall 16 of the crib bag 10 can be hung from a ceiling of a mine using the lifting lugs 22a, 22b so that the crib bag 10 hangs downwardly and is allowed to extend such that the bottom wall 18 is proximate to or contacts a floor of the mine when the bag 10 is extended. The crib bag 10 is then filled with a load-bearing material, such as cement or a cement compound, until the load-bearing material fills the chamber of the crib bag 10, creating a column extending between the floor and ceiling of the mine.

FIG. 2 is a perspective view of the crib bag 10. As shown, the top wall 16 includes a venting structure comprising an aperture 28 and a cover flap 30 terminating at a circular peripheral edge 32. The flap 30 is attached to a lower surface of the top wall 16 within the crib bag 10. The flap 30 extends beyond (has a greater diameter than) the aperture 28, and is partially attached to the top wall 16 such as by a plurality of radio frequency (RF) welds 34 to the inside surface of the top wall 16. The aperture 28 and the cover flap 30 can have different sizes and shapes. Other attachment techniques, such as sewing, could also be used to partially secure the flap 30 to the top wall 16. Together, the aperture 28 and the flap 30 form a vent that allows air to escape when the bag is being filled with a cement/cement compound. During filling, air can escape through areas that the flap 30 is not attached to the top wall 16 (between welds). However, when the bag 10 is completely filled, the cement/cement compound pushes the flap 30 against the top wall 16, thereby closing the vent to prevent spillovers and hazards associated therewith.

FIG. 3 is a top view of the crib bag 10. As shown, the cover flap 30 is attached (e.g., RF welded) to the top wall 16, preferably by a plurality of welds 34 extending from the peripheral edge 32 of the cover flap 30 to the edge of the aperture 28. Also, as shown, the plurality of welds 34 could be evenly spaced and radially aligned at 0, 120, and 240 degrees. Of course, a variety of other welding patterns/spacing can be used to partially connect the flap 30 to the top wall 16 to allow air to escape from the crib bag 10 while it is being filled with concrete.

FIG. 4 is a side view of the lifting lug 22a having a grommet 24a. The grommet 24a receives a roof bolt or other type of attachment for lifting and/or supporting the bag 10. It is understood that the lug 22b and grommet 24b discussed above have the same construction as the lug 22a and grommet 24a.

FIG. 5 is a partial sectional view of the side wall 12 taken along line B-B of FIG. 1, showing the helical rib 14. The rib 14 is captured within the side wall 12.

FIG. 6 is a partial internal view taken at location “C” of FIG. 1. Shown is an internal wire endcap 36 used at each end of the rib 14 to prevent the rib 14 from tearing and/or protruding through the sidewall 12.

FIG. 7 is an enlarged view taken at location “D” of FIG. 1. As can be seen, the side wall 12 is connected to the bottom wall 18 along the perimeter of the bottom wall 18, e.g., by stitching.

The valve 26 for introducing the cement/cement compound into the crib bag 10 is shown in greater detail in FIG. 8. The valve 26 could be a one-way check valve, such as a duck bill valve, as shown. Such a valve is disclosed in U.S. Pat. No. 7,530,369 to Anderson, the entire disclosure of which is incorporated herein by reference. Such a valve could include a threaded plug portion and corresponding threaded collar. The valve 26 includes a body 40 having an inner side wall 42 defining a through hole 44, an exterior surface 46, and an interior surface 48. The body 40 is preferably made of plastic, such as molded HDPE plastic. The valve 26 includes a flexible valve insert 50 having a generally v-shaped construction attached to the interior surface 48 of the body 40, which could be molded from EPDM rubber. The valve insert 50 allows for cement/cement compound to be pumped through the valve 26 and into the bag 10 but prevents it from flowing back out thereafter. The valve 26 further includes a flange 52 having a top surface 54. The exterior surface 46 of the body 40 includes threads 56. An O-ring 58, such as a Buna-N rubber O-ring, can be provided to create a seal when the valve 26 is engaged against the side wall 12.

FIG. 9 is a sectional view of the valve 26 interconnected with a collar 60, which receives the valve 26. The side wall 12 of the crib bag 10 is sandwiched between the flange 52 of the valve 26 and the collar 60 when the valve 26 is threaded into the collar 60. A set of washers 62a, 62b can be used to secure the valve 26 and the collar 60 to the bag 10.

The check valve assembly could be hand screwed together during production. A cement supply hose could be attached using an over center cam lock device when installed underground.

Having thus described the present invention in detail, it is to be understood that the foregoing Detailed Description of the invention is not intended to limit the spirit or scope thereof What is desired to be protected is set forth in the following claims.

Claims

1. A crib bag comprising:

a cylindrical side wall attached to a bottom wall and a top wall;

a vent at the top wall; and

a one-way valve at an upper portion of the cylindrical side wall.

2. The crib bag of claim 1 wherein the vent comprises an aperture in the top wall and a cover partially attached to an internal side of the top wall.

3. The crib bag of claim 1 wherein the one-way valve comprises a duck bill valve.

4. The crib bag of claim 1 wherein the one-way valve comprises a body having a flexible v-shaped insert.

5. The crib bag of claim 4 wherein the flexible v-shaped insert allows material to flow through the one-way valve and into the crib bag.

6. The crib bag of claim 5 wherein the flexible v-shaped insert prevents material from flowing out of the crib bag.

7. The crib bag of claim 2 wherein the cover has a greater diameter than the aperture.

8. The crib bag of claim 7, wherein the cover is partially attached to the top wall by a plurality of welds extending from a peripheral edge of the cover to an edge of the aperture.

9. The crib bag of claim 8, wherein each of the plurality of welds is evenly spaced and radially aligned.

10. The crib bag of claim 7, wherein the vent is self-closing and allows air to escape when the crib bag is being filled.

11. The crib bag of claim 10, wherein the cover cooperates with the top wall to close the vent.

12. The crib bag of claim 11, wherein the cover is moved against the top wall when the crib bag is completely filled, thereby closing the vent.

13. A method for forming a roof support column, the method comprising the steps of:

suspending a crib bag at a location;

filling a chamber of a crib bag with a load-bearing material through a one-way valve;

allowing air to vent from the crib bag through a vent as the crib bag is being filled; and

closing the vent when the crib bag is completely filled.

14. The method of claim 13, wherein the step of allowing air to vent from the crib bag comprises allowing venting of air through a self-closing aperture.

15. The method of claim 14, wherein the step of closing the vent comprises moving a cover against the aperture.

16. A crib bag comprising:

a cylindrical side wall attached to a bottom wall and a top wall, the cylindrical side wall having a chamber;

an aperture formed in the top wall to allow venting from the chamber; and

a cover having a greater diameter than the aperture, the cover closing the aperture after the cylindrical side wall is filled with a load-bearing material.

17. The crib bag of claim 16, further comprising a one-way valve at an upper portion of the cylindrical side wall.

18. The crib bag of claim 17 wherein the cover is partially attached to an inside surface of the top wall.

19. The crib bag of claim 18 wherein the aperture is self-closing.

20. The crib bag of claim 19 wherein the one-way valve comprises a body having a flexible v-shaped insert.