WO2005003609A1

WO2005003609A1 - Hydraulic fluid inlet valve

Info

Publication number: WO2005003609A1
Application number: PCT/ZA2003/000178
Authority: WO
Inventors: David Charles Tyrer; Brendan Robert Crompton
Original assignee: David Charles Tyrer; Brendan Robert Crompton
Priority date: 2003-07-01
Filing date: 2003-11-28
Publication date: 2005-01-13
Also published as: AU2003291219A1; ZA200506692B

Abstract

A valve (10) comprising a body (12) for attachment to a pressure vessel, a fluid passage (20, 26, 28) through the body between an inlet (28) and an outlet (21) into the vessel, spaced first (41) and second valve seats (30) in the fluid passage, a valve member (32) in the fluid passage which is movable from a first position in which a projecting shearable formation (36) on it is lifted from the first valve seat (41) to permit fluid flow past the valve member (32) into the vessel, a second position in which the formation (36) is moved onto the second valve seat (41) by pressurised fluid to be sheared at a predetermined pressure from the valve member (32) to enable the fluid to move the valve member (32) to a third position in which a second formation (40) on the valve member (32) seats on the second valve seat (30) to close the fluid passage and expose an indicator stem (34) on the valve member (32) at the passage inlet (28).

Description

HYDRAULIC FLUID INLET VALVE

FIELD OF THE INVENTION

[0001] This invention relates to a one-way hydraulic fluid inlet valve through which a pressure vessel may be filled with hydraulic fluid under pressure and which includes an indicator for indicating that the pressure vessel is filled with hydraulic fluid at or above a predetermined pressure.

SUMMARY OF THE INVENTION

[0002] According to the invention there is provided a valve comprising: a valve body which is adapted for attachment to a pressure vessel, a linear fluid passage through the body which, in use, extends between a fluid inlet on the outside of the pressure vessel and an outlet from the body into the pressure vessel cavity, first and second valve member seats which are spaced in an axial direction in the fluid passage from each other, a valve member in the fluid passage which is movable from a first position in which a radially projecting shearable formation on it is lifted from the first valve member seat to permit fluid to flow past the valve member into the pressure vessel, a second position in which the shearable formation is moved onto the second valve member seat by fluid in the pressure vessel at a predetermined pressure and which at a fluid pressure at or above the predetermined pressure is sheared from the valve member to enable the pressure fluid to move the valve member to a third position in which a second formation on the valve member seats on the second valve member seat to close the fluid passage to fluid flow from its outlet to its inlet, and an indicator stem on the valve member which is visible at the fluid passage inlet when the valve member is moved from its second to its third position of movement. [0003] The valve body conveniently comprises a first body portion which includes a major bore which terminates in the valve outlet into the pressure vessel cavity, in use, a stop formation which extends into the bore for limiting movement of the valve member to its first position of movement, and a second body portion which is sealingly engaged with the first a d includes a portion of the fluid passage which extends between the fluid inlet to the valve and the bore in the first body portion and the first and second valve member seats. The second body portion may include a spigot which is located in and sealingly engaged with the wall of the bore in the first body portion and a fluid hose coupling formation on a portion of its length which projects from the first body portion bore.

[0004] The portion of the fluid passage through the second body portion may be inwardly stepped, intermediate its ends, to a smaller cross-sectional dimension to define at the step the second valve member seat with a surface which extends outwardly from the fluid passage at or adjacent the end of the second body portion in the bore of the first body portion defining the first valve member seat.

[0005] The valve member may include a body which is movable in an axial direction in the large cross-sectional dimensioned portion of the fluid passage through the second body portion of the valve with the indicator stem projecting in an axial direction from the valve member body towards the inlet to the fluid passage so that when the valve member is moved from its second to its third position of movement the free end of the indicator stem is visible at the fluid passage inlet into the valve.

[0006] Preferably the fluid passage and the valve member are circular in cross-section with the diameter of the valve member body and the indicator stem being of lesser diameters than the portions of the fluid passage in which they are movable to permit fluid flow past the valve member when the shearable formation is lifted from the first valve member seat. [0007] The outer end of the major bore in the first body portion of the valve may terminate in a frusto conical dome in the body portion with the fluid passage outlet being a minor bore between the centre of the dome and the outside of the body and the portion of the valve member on the side of the shearable formation which faces the outlet could include at least one fluid passage through which fluid may flow from the fluid passage through the valve body to and from the minor bore outlet when the end of the valve member is stopped by the major bore dome at the limit of its first position of movement.

[0008] The shearable formation may preferably be a flange which is sealingly seated on the first valve member seat to close the valve to fluid flow from the pressure vessel, in use, by fluid at a pressure below the predetermined pressure.

[0009] The sealing flange may include at least one zone of weakness adjacent the valve member body which will facilitate shearing of the formation from the body at the predetermined pressure. The zone of weakness is defined by a groove in the shearable formation at its junction with the valve member body with the fluid pressure at which the formation is to be sheared from the body being dependent on the nature of the material from which the valve member is made and the depth of the groove into the formation.

[0010] A fluid bleed passage could be provided in one of the seating surfaces between the second valve member seat and the second formation on the valve member in the third position of movement of the valve member to enable the pressure vessel, in use, to yield under load by forcing fluid in it through the bleed passage.

[0011] In a preferred form of the invention the valve member may be made from a suitable plastics material. The invention extends also to a rock anchor wherein at least a portion of the length of anchor tendon is a metal tube which is radially expansible by water under pressure with the anchor including the filler valve of the invention through which the expansible portion of the anchor tendon may be filled with water under pressure.

BRIEF DESCRIPTION OF THE DRAWINGS

[0012] An embodiment of the invention is now described by way of example only with reference to the drawings in which :

Figure 1 is a sectioned side elevation of the valve of the invention,

Figures 2 and 3 are views similar to that of Figure 1 with the valve member of the valve shown in its two limit positions of operations,

Figure 4 is a plan view of the valve member as seen from above in Figures 1 and 2,

Figure 5 is a fragmentary side elevation of a portion of the valve member, and

Figure 6 is a side elevation of a radially expansible rock anchor including the valve of the invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

[0013] The valve 10 of the invention is shown in the drawings to include a valve body 12 and a valve member 14.

[0014] The valve body comprises first and second body portions 16 and 18.

[0015] The body portion 16 includes a major bore 20 which terminates in a frusto conical domed upper end which leads into a minor bore 21. The body component 18 includes a spigot 22 which is a high friction sealing press fit in the bore 20 of the body portion 16 and carries, on the outside of the body portion 16, a button-type hose connector formation 24. The valve body portion 18 includes a concentric fluid passage bore which is stepped from an upper large diameter portion 26 to a smaller diameter portion 28 to define at the intersection of the bores a valve seat 30.

[0016] The valve member 14, in this embodiment of the invention, is made from a plastics material such as a suitable polymer and, like the bore through the second body portion 18 of the valve, has an upper head portion 32 and a smaller diameter indicator stem 34 which is situated in the bore 28 of the body portion 18, as shown in the drawings. Both the head and indicator stem are of a smaller diameter than that of the bore portions 26 and 28 in which they are located for the passage of fluid past them, in use. The valve member head 32 carries a radially projecting valve member formation 36 and flutes 38, which are more clearly seen in Figure 4, which extend upwardly from the formation 36 to terminate in a conical seat 39 at the upper end of the valve member. The underside of the valve member head 32 is tapered complementally to the base of the valve seat 30 and forms a second valve member 40 of the valve.

[0017] In use, the body portion 16 of the valve is welded to the pressure vessel around a hole into the vessel with the minor bore 21 of the first body portion 16 of the valve located in the cavity of the pressure vessel.

[0018] The pressure vessel may be a sheet metal mine prop preload device which is inflatable by water under pressure to extend the prop in its axial direction for location between the hanging and foot walls in a mine working under a preload pressure or it could be located in the mouth of a radially expansible metal rock anchor which is radially expanded into gripping contact with the wall of a hole in which it is located by water under pressure.

[0019] In use, a coupling on a high pressure water hose is connected to the button formation 24 on the outside of the vessel and water under high pressure is fed into the valve bore 28. The water passes over the indicator stem 34, enters the bore 26 of the valve body portion 18, passes upwardly over the valve member head 32 to lift the valve member, by means of the formation 36 from the position illustrated in Figure 1 to that illustrated in Figure 2 wherein the conical seat 39 of the head 32 seats against the frusto conical roof of the bore 20 in the body portion 16 of the valve. The water flows around the valve member formation 36 and through the flutes 38 in the head into the minor bore 21 and from there into the pressure vessel to fill the vessel with water to a predetermined pressure at which the vessel will be fully expanded.

When the water hose coupling is released from the hose connector formation 24 the drop in water pressure in the water passage through the valve body 12 will cause the water pressure differential across the valve member 36 to slam the member 36 onto its seat 41 on the upper surface of the body portion 18, as shown in Figure 1 , to trap the water under pressure in the pressure vessel. At the design pressure the formation 36 is adapted to shear from the head 32 to enable the valve member to be forced downwardly from the position shown in Figure 1 to that shown in Figure 3 at which the seat 40 on the valve member head sealingly seats on the valve seat 30 to prevent water leaving and so pressure loss from the pressure vessel.

[0020] In the Figure 3 position of the valve member the outer end of its valve member stem 34 is situated, as shown in Figure 3, adjacent, at or slightly beyond the mouth of the water inlet bore 28 to indicate to an observer that the pressure vessel is water filled to the design pressure. Preferably the valve member 14 is Day-Glo coloured so that the end of the indicator stem 34 is more visible to the observer than would otherwise be the case.

[0021] Should the pressure vessel not be filled with water to the predetermined design pressure the shearable formation 36 will not be sheared from the valve member and will remain seated on its seat on the upper end of the valve body portion 18 to shut the valve to fluid flow towards its inlet. In this position of the valve member the end of the indicator stem will remain hidden from view to indicate inadequate inflation of the pressure vessel.

[0022] In Figure 6 the valve 10 of this invention is shown, in use, as the water filler valve for an expansible rock bolt 46. The rock bolt includes an elongated tube of ductile metal which includes one or more inward folds in its wall to reduce its cross-sectional dimension and to allow for radial expansion by water under pressure.

[0023] A feature of the valve of this invention is that the valve member 14 is movable between its three positions of movement in the valve fluid passage solely by water under pressure without the assistance of or against any form of biasing means such as springs or the like which would otherwise add to the cost of the valve.

[0024] The invention is not limited to the precise details as herein described. For example, the valve member shearable formation 36 could have a standard thickness with the fluid pressure at which it will be sheared from the valve member head being determined by the depth of a groove 42 which surrounds the valve member against the body 32 on the underside of the formation 36, as shown in Figure 5. Additionally, should it be desirable to provide the pressure vessel with a degree of yieldability under load the underside of the valve member seat 40 or the seat 30 could be provided with a radially directed groove 44, shown only in Figure 3, which will enable water and so internal pressure to be bled from the pressure vessel by the external load on it. The rate at which the pressure vessel is to be yieldable will be dependent on the cross-sectional dimension of the groove 44. Yet further, the body component 18 spigot 22 could be threadedly engaged with a suitable sealant in the bore 20 of the component 16 in place of the press fit described above.

Claims

1. A valve [10] comprising : a valve body [12] which is adapted for attachment to a pressure vessel, a linear fluid passage [20,26,28] through the body [12] which, in use, extends between a fluid inlet on the outside of the pressure vessel and an outlet [21] from the body into the pressure vessel cavity, characterised in that the valve [10] includes: first and second valve member seats [41 and 30] which are spaced in an axial direction in the fluid passage [20,26,28] from each other, a valve member [14] in the fluid passage [20,26,28] which is movable from a first position in which a radially projecting shearable formation [36] on it is lifted from the first valve member seat [41] to permit fluid to flow past the valve member [14] into the pressure vessel, a second position in which the shearable formation [36] is moved onto the second valve member seat [30] by fluid in the pressure vessel at a predetermined pressure and which at a fluid pressure, at or above the predetermined pressure, is sheared from the valve member [14] to enable the pressure fluid to move the valve member [14] to a third position in which a second formation [40] on the valve member [14] seats on the second valve member seat [30] to close the fluid passage [20,26,28] to fluid flow from its outlet [21] to its inlet, and an indicator stem [34] on the valve member [14] which is visible at the fluid passage inlet when the valve member is moved from its second to its third position of movement.

2. A valve as claimed in claim 1 wherein the valve body [12] comprises a first body portion [16] which includes a major bore [20] which terminates in the valve outlet [21] into the pressure vessel cavity, in use, a stop formation which extends into the bore [20] for limiting movement of the valve member [14] to its first position of movement, and a second body portion [18] which is sealingly engaged with the first [16] and includes a portion [26,28] of the fluid passage [20,26,28] which extends between the fluid inlet to the valve and the bore [20] in the first body portion [16] and the first and second valve member seats [41 and 30].

3. A valve as claimed in claim 2 wherein the second body portion [18] includes a spigot [22] which is located in and sealingly engaged with the wall of the bore [20] in the first body portion [18] and a fluid hose coupling formation [24] on a portion of its length which projects from the first body portion bore [20].

4. A valve as claimed in either one of claims 2 or 3 wherein the portion of the fluid passage [26,28] through the second body portion [18] is inwardly stepped, intermediate its ends, to a smaller cross-sectional dimension to define at the step the second valve member seat [30] with a surface which extends outwardly from the fluid passage [26] at or adjacent the end of the second body portion [18] in the bore [20] of the first body portion [16] defining the first valve member seat [41].

5. A valve as claimed in claim 4 wherein the valve member [14] includes a body [32] which is movable in an axial direction in the large cross-sectional dimensioned portion [26] of the fluid passage [26,28] through the second body portion [18] of the valve [10] with the indicator stem [34] projecting in an axial direction from the valve member body [12]towards the inlet to the fluid passage [26,28] so that when the valve member [14] is moved from its second to its third position of movement the free end of the indicator stem is visible at the fluid passage inlet into the valve.

6. A valve as claimed in claim 5 wherein the fluid passage [20,26,28] and the valve member [14] are circular in cross-section with the diameter of the valve member body [32] and the indicator stem [34] being of lesser diameters than the portions [26,28] of the fluid passage in which they are movable to permit fluid flow past the valve member 5 [14] when the shearable formation [36] is lifted from the first valve member seat [41].

7. A valve as claimed in claim 6 wherein the outer end of the major bore [20] in the first body portion [16] of the valve [10] terminates in a frusto conical dome in the body portion with the fluid passage outlet being a minor bore [21] between the centre of the dome and the outside of the body and the portion of the valve member on the side of

I0 the shearable formation [36] which faces the outlet [21] includes at least one fluid passage [38] through which fluid may flow from the fluid passage [20,26,28] through the valve body [12] to and from the minor bore outlet [21] when the end [39] of the valve member [14] is stopped by the major bore [20] dome at the limit of its first position of movement.

15 8. A valve as claimed in either one of claims 6 or 7 wherein the shearable formation [36] is a flange which is sealingly seated on the first valve member seat [41] to close the valve to fluid flow from the pressure vessel, in use, by fluid at a pressure below the predetermined pressure.

9. A valve as claimed in claim 8 wherein the sealing flange [36] includes at least one zone 10 of weakness [42] adjacent the valve member body [32] which will facilitate shearing of the formation [36] from the body [32] at the predetermined pressure.

10. A valve member as claimed in claim 9 wherein the zone of weakness is defined by a groove [42] in the shearable formation [36] at its junction with the valve member body [32] with the fluid pressure at which the formation [36] is to be sheared from the body [32] being dependent on the nature of the material from which the valve member [14] is made and the depth of the groove [42] into the formation.

11. A valve as claimed in any one of the above claims in which a fluid bleed passage [44] is provided in one of the seating surfaces [30,40] between the second valve member seat [30] and the second formation [40] on the valve member [14] in the third position of movement of the valve member [14] to enable the pressure vessel, in use, to yield under load by forcing fluid in it through the bleed passage [44].

12. A valve as claimed in any one of the above claims wherein the valve member [14] is made from a suitable plastics material.

13. A rock anchor wherein at least a portion of the length of anchor tendon [46] is a metal tube which is radially expansible by water under pressure with the anchor including a filler valve [10] as claimed in any one of the above claims through which the expansible portion of the anchor tendon [46] may be filled with water under pressure.