US20060000092A1

US20060000092A1 - Fire hydrant valve seat flange

Info

Publication number: US20060000092A1
Application number: US11/125,803
Authority: US
Inventors: Todd Ingalls; Kevin Wright; Bryan Griffin; Richard Brooks
Original assignee: Individual
Current assignee: Individual
Priority date: 2004-06-30
Filing date: 2005-05-10
Publication date: 2006-01-05
Also published as: US6929022B1

Abstract

A fire hydrant having a valve seat flange with an integral liner. In one embodiment, the fire hydrant includes a valve seat flange disposed between a standpipe and a hydrant shoe. The valve seat flange includes a standpipe neck defining internal threads to directly connect to the standpipe and a base flange to directly connect to the hydrant shoe. The liner includes an outer peripheral edge that is entrapped within the valve seat flange and an inner circumferential surface defining threads for receiving the valve seat of a valve assembly. The present invention also discloses a process of manufacturing a valve seat flange, including the steps of: (a) manufacturing the liner, (b) incorporating the liner into a core with the outer peripheral region of the liner exposed, (c) placing the integral core/liner into the valve seat flange mold and (d) forming the valve seat flange around the liner with the valve seat flange entrapping the outer peripheral region of the liner.

Description

BACKGROUND OF THE INVENTION

The present invention relates to fire hydrants and more particularly to a fire hydrant with a unique valve seat flange and a method for manufacturing the same.
Fire hydrants are commonplace in our society providing a ready source of water to, among other things, help confront fire hazards. Fire hydrants typically remain idle for long periods of time. As a result, the internal workings of the hydrant must be able to withstand long periods of time in the presence of water without corroding or otherwise becoming nonfunctional.
With conventional fire hydrants, the flow of water through the hydrant is controlled by a valve. The valve is typically located below ground level within the hydrant shoe. A conventional valve includes a valve seat that is threaded in place within or adjacent to the hydrant shoe. The threaded seat permits the valve to be removed when maintenance is required. For example, the valve can be removed to permit replacement of the valve seal or to permit installation of a new valve. To ease removal of the valve, the valve seat is typically threadedly seated within a brass (or bronze) liner. The brass liner provides brass threads that resist corrosion and facilitate removal of the valve even after extended periods of time. Often, the valve seat is also brass so that the threaded interface between the valve seat and the brass liner includes intermeshing brass threads.
In many conventional constructions, the brass liner is sandwiched in one way or another between a flange at the lower end of the standpipe and the hydrant shoe. The typically sandwiched construction provides a number of part interfaces that provide numerous potential leakage paths. Further, the sandwiched construction may not provide the strength desired in some applications. Additionally, the separate brass liner increases parts inventory and complicates the assembly process.

SUMMARY OF THE INVENTION

The aforementioned problems are overcome by the present invention wherein a fire hydrant is provided with a valve seat flange having an integral liner. In one embodiment, the valve seat flange is disposed between the standpipe and the hydrant shoe, and includes a threaded brass liner that is insert cast as an integral part of the valve seat flange.
In one embodiment, the valve seat flange includes an internally threaded standpipe neck for threadedly mounting the valve seat flange to the lower end of the standpipe and planar base for connecting to the hydrant shoe. The liner may include a contoured outer peripheral region that interlocks with the valve seat flange to reduce the likelihood of rotation of the liner with respect to the valve seat flange.
The valve seat flanges may be manufactured in a process including the steps of: (a) manufacturing the liner, (b) incorporating the liner into a core with the outer peripheral region of the liner exposed, (c) placing the integral core/liner into the valve seat flange mold, (d) forming the valve seat flange around the liner with the valve seat flange entrapping the outer peripheral region of the liner.
The present invention provides a hydrant with a simple and effective valve seat that provides the assembly with increased strength and also reduces the number of potential leak paths. Additionally, the integral liner eliminates the need for handling and assembly of a separate liner. The integral liner is also entrapped within the valve seat flange, thereby reducing the potential for axial movement of the liner with respect to the flange.
These and other objects, advantages, and features of the invention will be readily understood and appreciated by reference to the detailed description of the preferred embodiment and the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross-sectional view of a fire hydrant incorporating a valve seat flange in accordance with an embodiment of the present invention.
FIG. 2 is a cross sectional view of the lower standpipe with the valve seat flange.
FIG. 3 is a top plan view of the valve seat flange.
FIG. 4 is a cross sectional view of the valve seat flange taken along line IV-IV of FIG. 3.
FIG. 5 is a top plan view of the valve seat liner.
FIG. 6 is a cross sectional view of the valve seat liner taken along line VI-VI of FIG. 5.
FIG. 7 is a cross sectional view of the valve seat liner taken along line VII-VII of FIG. 5.
FIG. 8 is a cross sectional view of casting apparatus for use in manufacture of one embodiment of the present invention.
FIG. 9 is a top plan view of the rough valve seat flange after casting and before machining.
FIG. 10 is a cross sectional view of the rough valve seat flange taken along line X-X of FIG. 9.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

A fire hydrant incorporating a preferred embodiment of the present invention is shown in FIG. 1 and generally designated 10. The fire hydrant 10 includes a valve 12 mounted within a valve seat flange 14. The valve seat flange 14 is disposed between the standpipe 16 and the hydrant shoe 18, and includes an integral liner 20 for threadedly receiving the valve assembly 22. The integral liner 20 provides an integrated corrosion resistant liner for use in seating the valve assembly 22. The valve assembly 22 is threaded into the liner 20.
Fire hydrants are well known and accordingly will only be described herein to the extent helpful in disclosing the present invention. For purposes of disclosure, the present invention is described in connection with a conventional WaterMaster® fire hydrant available from East Jordan Iron Works of East Jordan, Mich. The present invention is, however, readily incorporated into a wide variety of other fire hydrants, and the present invention should be interpreted as being limited to any particular fire hydrant construction. In summary, the fire hydrant 10 of the illustrated embodiment includes a hydrant shoe 18 which functions as an inlet, a valve seat flange 14 to receive the valve assembly 22, a lower standpipe 16, an upper standpipe 24 and a top bonnet 26 that supports, among other things, the nozzle 28 and valve operating nut 30.
As discussed above, the valve seat flange 14 is interposed between the lower standpipe 16 and the hydrant shoe 18 to operatively receive the valve assembly 22. The valve seat flange 14 includes a somewhat tubular body 32 having a standpipe neck 34 at its upper end and a base flange 36 at its lower end. Referring now to FIG. 2, the standpipe neck 34 is interconnected with the lower standpipe 16. In the illustrated embodiment, the lower standpipe 16 is threadedly connected with the valve seat flange 14. More specifically, in this embodiment, the lower standpipe 16 includes external threads 36 that are interfitted with internal threads 38 defined in the standpipe neck 34. The base flange 36 generally includes a planar peripheral flange 50 surrounding an annular rim 52. The peripheral flange 50 is generally planar providing a flat surface for mounting to the upper mounting surface of the hydrant shoe 18. The peripheral flange 50 defines a plurality of bolt holes 51 for intersecuring the valve seat flange 14 and hydrant shoe 18. The rim 52 is closely fitted within the hydrant shoe 18 to center the valve seat flange 14 and strengthen the connection between the valve seat flange 14 and the hydrant shoe 18. A lower o-ring 54 is preferably fitted to the base flange 36 within and an o-ring seat 56 to facilitate a leaktight seal between the valve seat flange 14 and the hydrant shoe 18. The valve seat flange 14 includes a first reduced diameter portion 40, which entraps the integral liner 20. The upper end of the first reduced diameter portion 40 defines a surface to function as a stop for the threaded lower standpipe 16. As described in more detail below, the valve seat flange 14 is preferably formed about the liner 20 so that the two elements are integral with one another. The liner 20 is generally ring-shaped defining internal threads 42. The liner 20 and its internal threads 42 are dimensioned to threadedly receive the valve assembly 22. The liner 20 is preferably manufactured from bronze, but may be manufactured from other materials having sufficient strength and corrosion resistance. For example, the liner may be brass in some applications. In this embodiment, the liner 20 is manufactured in rough form for casting and is machined after incorporation into the valve seat flange 14. The rough liner 20 is shown in FIGS. 5-7. The rough liner 20 of this embodiment includes a plurality of internal lugs 62 a-d that interlock with the core 100 to reduce the possibility of the liner 20 rotating within the core 100. The lugs 62 a-d protrude from the inner circumferential surface of the liner 20. As described in more detail below, the inner circumferential surface is ultimately machined to provide threads for interfacing with the valve assembly 22. This machining process removes the lugs 62 a-d. The rough liner 20 may also define a plurality of grooves 64 a-f on the outer circumferential surface of the liner 20. The grooves 64 a-f interlock with the valve seat flange 14 when valve seat flange 14 is formed about the liner 20. This reduces the possibility of the liner 20 rotating within the valve seat flange 14. The grooves 64 a-f may be replaced by notches, protrusions or other variations in shape that provide an interlock between the liner 20 and the valve seat flange 14. The valve seat flange 14 includes a second reduced diameter portion 44. The second reduced diameter portion 44 is dimensioned to closely receive the valve seat 46 of the valve assembly 22. The interior surface of the second reduced diameter portion 44 is preferably machined to provide a smooth, clean surface to interface with the o-rings 48 a-b of the valve seat 46. The valve seat flange 14 also defines an annular drain recess 57 and a pair of drain holes 58 a-b that permit water to drain from the standpipes 16, 24 and bonnet 26 when the valve assembly 22 is in the closed position. The drain mechanism is generally conventional and therefore will not be described in detail. Suffice is to said, however, that the drain recess 57 and drain holes 58 a-b in the illustrated embodiment are defined in the second reduced diameter portion 44 so that they are disposed between the valve seat o-rings 60 a-b.
A preferred method for manufacturing the valve seat flange 14 using a casting process will now be described with reference to FIGS. 8-10. The rough liner 20 is manufactured separately from the remainder of the valve seat flange 14 (See FIGS. 5-7). The liner 20 is preferably cast from bronze or brass using conventional casting tools and methods, but may be machined or otherwise formed. The liner 20 is not necessarily manufactured from bronze or brass and may be manufactured from other materials having sufficient strength and corrosion resistance.
The liner 20 is insert cast into valve seat flange 14 using a conventional casting core, for example, sand core 100. The core 100 maintains the liner 20 in the correct position during the process of casting the valve seat flange 14. The rough liner 20 is integrated into the core 100 using conventional core manufacturing techniques and apparatus. As shown in FIG. 8, the rough liner 20 is integrated into core 100 with its outer peripheral region exposed, and more specifically, that portion of the outer periphery of the liner 20 that is to be entrapped within the valve seat flange 14.
The valve seat flange 14 is cast, for example, from a ductile iron. In this embodiment, the valve seat flange 14 is cast using a conventional sand casting apparatus 90. In summary, a pattern (not shown) of the valve seat flange 14 is preformed. The pattern is shaped to occupy the space of the valve seat flange 14 and the core 100. The pattern is pressed into the cope 102 and drag 104 to define opposed portions of the casting cavity 106. A runner gate system (not shown) is also defined in the cope 102 to permit the desired molten material to be poured into the cavity 106. Before closing the cope 102, the core 100 is placed in the cavity 106 where it remains during the casting process. The cope 102 is then closed on top of the drag 104 with the cope 102 and drag 104 cooperatively defining a cavity 106 surrounding at least portions of the core 100 in the shape of the valve seat flange 14. Molten material, such as ductile iron, is then poured into the cavity 106 through runner gate system. The molten material flows down into the cavity 106 where it is permitted to cure. After curing, the completed part is removed from the cope 102 and drag 104. The core 100 is broken apart and removed from within the part leaving behind the rough liner 20 entrapped within the valve seat flange 14. The rough valve seat flange 14 is shown in FIGS. 9 and 10. As shown, the liner 20 continues to include lugs 62-a-d. In addition, the interfacing surfaces of the valve seat flange 14 remain rough. The valve seat flange 14 is then finished as desired, for example, by machining to remove the runner gate system and any undesired rough surfaces. In this embodiment, the finishing process includes the step of forming internal threads 38 in the standpipe neck 34 to threadedly receive the lower end of the lower standpipe 16. Also, the bottom surface of the base flange 36 is machined to provide a smooth interface with the top flange of the hydrant shoe 18. Similarly, the interior surface of the second reduced diameter portion 44 is machined to provide a smooth interface with the valve seat 46 and valve seat o-rings. The annular drain recess 57 and drain holes 58 a-b are also preferably, but not necessarily, machined into the valve seat flange 14 after the casting process is complete. Further, in this embodiment, the inner circumferential surface of the liner 20 is machined to form threads 42. The threads 42 may, however, be formed before or after the valve seat flange 14 casting process.
The valve seat flange 14 is installed in the hydrant 10 by aligning flange 14 and shoe 18 so that the rim 52 is fitted within the shoe 18. The valve seat flange 14 is then secured to hydrant shoe 18, for example, by bolts or other fasteners (not shown) extending through the bolt holes 51 in the base flange 36 and the corresponding top flange of the hydrant shoe 18. The valve assembly 22 may then be installed within the valve seat flange 14. The valve seat 46 is threaded into the liner 20 creating a brass-on-brass threaded interface. The valve seat 46 is threaded into the liner 20 until the bottom end of the valve seat 46 abuts the upper surface of the second reduced diameter portion 44. This helps to ensure proper positioning of the valve assembly 22 within the valve seat flange 14. The lower standpipe 16 is then installed on the valve seat flange 14. The threaded lower end of the standpipe 16 is threaded into the standpipe neck 34. The lower standpipe 16 is threaded into the valve seat flange 14 until the bottom end of the lower standpipe abuts the top surface of the first reduced diameter portion 40. In that way, the first reduced diameter portion 40 helps to ensure proper positioning of the lower standpipe 16. The remaining portions of the hydrant 10 are assembled in a conventional manner.
The above description is that of a preferred embodiment of the invention. Various alterations and changes can be made without departing from the spirit and broader aspects of the invention as defined in the appended claims, which are to be interpreted in accordance with the principles of patent law including the doctrine of equivalents. Any reference to claim elements in the singular, for example, using the articles “a,” “an,” “the” or “said,” is not to be construed as limiting the element to the singular.

Claims

1-6. (canceled)

7. A method for manufacturing a valve seat flange for a fire hydrant, comprising the steps of:

manufacturing a liner;

forming a casting core incorporating the liner, an outer peripheral portion of the liner being exposed;

inserting the core incorporating the liner into a casting cavity;

casting a valve seat flange by pouring molten material into the casting cavity about the core, the outer peripheral portion of the liner being entrapped within the material forming the valve seat flange; and

removing the core from the cast valve seat flange leaving the liner integral within the valve seat flange.

8. The method of claim 7 further comprising a step of forming internal threads on an internal circumferential surface of the liner.

9. The method of claim 8 further wherein said step of manufacturing said liner includes a step of forming at least one of a protrusion and a recess in the outer peripheral surface of said liner.

10. The method of claim 8 wherein said casting step includes the step of forming a standpipe neck to directly mount to a hydrant standpipe.

11. The method of claim 10 wherein said casting step includes the step of forming a base flange to directly mount to a hydrant shoe.

12. The method of claim 11 wherein said casting step includes the step of forming an inner rim within the base flange, the inner configured to be fitted within a hydrant shoe.

13. The method of claim 12 further including the step of forming an o-ring seat in at least one of the base flange and the inner rim.

14. The method of claim 13 wherein the liner is manufactured from one of bronze and brass, and the valve seat flange is manufactured from ductile iron.

15-19. (canceled)