AU2004200765A1 - Sealing means - Google Patents

Description

AUSTRALIA

PATENTS ACT 1990 COMPLETE SPECIFICATION FOR A STANDARD PATENT (Original) APPLICATION NO:

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COMPLETE SPECIFICATION LODGED:

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RELATED ART: NAME OF APPLICANT: ACTUAL INVENTOR: ADDRESS FOR SERVICE: INVENTION TITLE: CAMCO DREICO INDUSTRIAL SERVICES PTY

LTD

RAINER DREIER LORD COMPANY, Patent Trade Mark Attorneys, of 4 Douro Place, West Perth, Western Australia, 6005, AUSTRALIA.

"SEALING MEANS" DETAILS OF ASSOCIATED PROVISIONAL APPLICATION NO'S: AUSTRALIAN PROVISIONAL PATENT APPLICATION NUMBER 2003900893 FILED ON 27 FEBRUARY 2003.

The following Statement is a full description of this invention including the best method of performing it known to me/us: 1

TITLE

"SEALING MEANS" The present invention relates to a sealing means, such as a spade arrangement used to seal valves, pressure vessels and the like.

Many industrial and mineral processing operations require the transportation of substances through pipes. It is frequently preferable to prevent exposure of these substances to the environment outside of the pipes. This is particularly the case where the substances being transported include noxious gases. Similarly, in situations where the substances being transported may react chemically with air, it is necessary to prevent exposure of the substances to the outside environment.

The sealing of pipe joints by the use of gaskets is well known, and this provides a pipe line with the necessary sealing during normal use.

It is common for a section of a pipe line to require maintenance. When this is required, it is necessary to provide a seal between that section of the pipe line and the remainder of the pipe line. If such a seal can not be provided, it is necessary to depressurise the entire pipe line before maintenance work can be done.

The use of valves to isolate a section of piping is well known. Known valves which rely on pressure within the pipe in order to seal are not considered safe for use in hazardous, pressurised systems. It is desired to provide a valve which engages the pipe in a positive seal.

A further disadvantage of known valves is that maintenance of the valve itself, and wearable components such as gaskets, can be difficult.

The present invention attempts to overcome at least in part some of the aforementioned disadvantages of previous sealing means.

In accordance with one aspect of the present invention there is provided a sealing means having a fluid flow path and a spade having an open portion and a closed portion, the sealing means having an open position whereby the open portion of the spade is within the fluid flow path and a closed position whereby the closed portion of the spade is within the fluid flow path, the sealing means having a first position wherein the spade is prevented from moving between an open position and a closed position, and the sealing means having a second position wherein the spade is permitted to move between an open position and a closed position.

The present invention will now be described, by way of example, with reference to the accompanying drawings, in which: Figure 1 is a cross-sectional elevation view of a valve having a sealing means in accordance with the present invention; Figure 2 is an enlarged view of a portion of Figure 1; Figure 3 is a cross sectional plan view of the valve of Figure 1; Figure 4 is an isometric view of a spade used in the valve of Figure 1; and Figure 5 is a cross-sectional elevation view of a portion of the valve of Figure 1 with an associated emergency release assembly attached.

Referring to the Figures, there is shown a valve 10 with a spade arrangement, the valve 10 having an inlet 12 and an outlet 14. It will be appreciated that the valve may be arranged with the fluid flowing in either direction between the inlet 12 and the outlet 14. A fluid flow path extends between the inlet 12 and the outlet 14, the fluid flow path comprising a first pipe portion 16, a spade ring 18 and a second pipe portion The first and second pipe portions 16, 20 are internally lined by a wear liner 17.

The first pipe portion 16, spade ring 18 and second pipe portion 20 are all substantially circular in cross section, with a common internal diameter. The first pipe portion 16, spade ring 18 and second pipe portion 20 each have an axis which lies along a central axis extending between the inlet 12 and the outlet 14.

An inlet flange 21 abuts the first pipe portion 16 adjacent the inlet 12. The inlet flange 21 is arranged to allow the inlet 12 of the valve 10 to be fluidly connected to a pipe.

The inlet flange 21 is integral with the first pipe portion 16.

The second pipe portion 20 has an inner portion 23 adjacent the spade ring 18 and an outer portion 24 remote from the spade ring 18. The outer portion 24 has a large external diameter in comparison with the inner portion 23.

An outlet flange 22 abuts the outer portion 24 of the second pipe portion 20 adjacent the outlet 14. The outlet flange 22 is arranged to allow the outlet 14 of the valve 10 to be fluidly connected to a pipe. The outlet flange 22 is fixed to the second pipe portion 20 by suitable means such as welding.

The outer portion 24 of the second pipe portion 20 has an external lip 26 extending in an axial direction about an inner edge of the outer portion 24.

A ring cylinder 28 extends radially about the second pipe portion 20 adjacent the outer portion 24. The ring cylinder 28 has an outer annular portion 30 and an inner cylindrical portion 32. An annular aperture 34 is located within the inner cylindrical portion 32, extending from the outer portion 24 in a direction generally towards the inlet 12. An actuating means such as a hydraulic piston 36 is located there within.

A pressure sealing bellow 38 extends about the second pipe portion 20 adjacent the ring cylinder 28. The pressure sealing bellow 38 is attached to the ring cylinder 28 by suitable means such as welding.

A main body portion 40 extends partially about a portion of the fluid flow path including the spade ring 18. The main body portion 40 comprises a first radial portion 41 connected at an outer end thereof to the outer annular portion 30 of the ring cylinder 28 by suitable means such as by bolts 51, an axial arm 42 spaced from the fluid flow path, and a second radial portion 44 connected at an inner end thereof to the first pipe portion 16. An annular space 46 is thus defined between within the main body portion 40 and the fluid flow path. The radial arm 44 includes gas inlets 48 which are fluidly connected to the annular space 46.

A stiffening brace 43 may be applied about the main body 40 as shown in Figure 3.

A spring housing 50 extends about the outer portion 24 of the second pipe portion from a first end adjacent the outlet flange 22 to a second end adjacent the ring cylinder 28. The spring housing 50 is bolted to the ring cylinder 28 by spring bolts 52.

The spring housing 50 is maintained in a sliding relationship with the radial edge of the outlet flange 22. A resilient ring seal 53 may be provided between the spring housing 50 and the outlet flange 22.

A spring cavity 54 is defined between the spring housing 50 and the outer portion 24 of the second pipe portion 20. A resilient means in the form of a plurality of bellville springs 56 is provided within the spring cavity 54. The springs 56 are arranged to act at an outer end against the spring housing 50, and at an inner edge against the lip 26 of the actuator base 24. The springs 56 include wedges 57 which limit the possible compression of the springs 56.

The spade arrangement will now be described with particular reference to Figure 1.

The valve 10 includes a first spade access region 60 located above the spade ring 18 and a second spade access region 62 located beneath the spade ring 18. Each of the first and second spade access regions 60, 62 have access covers 64 which may be opened by a user.

A spade actuating means 66 in the form of a hydraulic cylinder is located above the first spade access region A spade 67 extends downwardly from the spade actuating means 66. The spade 67 can best be seen in Figure 4.

The spade 67 comprises a substantially rectangular sliding member 68, having two spade rings 18 positioned at opposed ends of the sliding member 68. Each of the spade rings 18 has a coupling means 69 located about the periphery thereof.

The coupling means 69 is arranged to receive a closed spade insert 70 or an open spade insert 71. The open and closed spade inserts 70, 71 each have complementary coupling means to enable coupling of the spade inserts 70, 71 to the spade rings 18.

The closed spade insert 70 acts to provide a seal against a spade ring 18, and so provide a barrier between opposed sides of the spade 67. The open spade insert 71 consists primarily of annular gaskets, which permit communication between opposed sides of the spade 67. The spade 67 of the drawings is arranged with a closed spade insert 70 in an upper spade ring 18 and an open spade insert 71 in a lower spade ring 18.

Spade guides 72 are arranged on either side of the spade 67 adjacent to the first and second pipe portions 16,20 as shown in Figure 3. The spade 67 is slidably received within the spade guides 72, and is thus constrained to move relative to the spade guides 72 in a single direction.

The spade arrangement further includes a plurality of purge valves 74 located above the first spade access region 60. The first access region includes an "open" indicator 76, and the second access region includes a "closed" indicator 78.

In a preferred embodiment of the invention, the valve 10 further includes an emergency release assembly 80 mounted to the outlet flange 22. The emergency release assembly 80 comprises a substantially cylindrical inner annular flange 82, and an outlet weldneck 84 mounted to the inner annular flange 82. The inner annular flange 82 and the outlet weldneck 84 each have a central bore which is substantially equal to the bores of the first and second pipe portions 16, Preferably, the outlet weldneck 84, inner annular flange 82 and outlet flange 22 are connected by connecting bolts 86 passing therebetween.

An annular collar 90 is mounted about the inner annular flange 82 and outlet weldneck 84. The annular collar 90 includes a substantially cylindrical inner portion 92 adjacent the inner annular flange 82 and outlet weldneck 84, and an annular outlet portion 94 extending away from the inner annular flange 82 in a radial direction. The annular collar 90 is located relative to the inner annular flange 82 by means of corresponding shoulders on the outer surface of the inner annular flange and the annular collar 90. The annular collar is connected to the outlet weldneck 84 by means of a plurality of radially aligned bolts 96.

7 The annular collar 90 includes a plurality of cylindrical recesses 98 which extend inwardly of a front surface 100 of the annular outlet portion 94. In a preferred embodiment of the invention there are three recesses 98 located at 1200 intervals about the front surface 100. The recesses 98 are oriented towards the spring housing Each of the recesses 98 is arranged to receive a piston 102.

In use, the valve 10 is moveable between a first position and a second position.

When the valve 10 is in the first position, as shown in the drawings, the bellville springs 56 provide a compressive force between the second pipe portion 20 and the spring housing 50. This force urges the second pipe portion 20 towards the first pipe portion 16.

The force acting on the spring housing 50 is transferred through the spring bolts 52 to the main body 40 and first pipe portion 16, urging the first pipe portion 16 towards the second pipe portion It will be appreciated that the compressive force can be varied by adjustment of the spring bolts 52.

In this way the spade ring 18 is clamped between the first pipe portion 16 and the second pipe portion 20 such that an air tight seal is created about the join between the pipe portions. When the spade ring 18 contains an open insert 71, matter can thus be transported through the valve 10 when in the first position without leakage. When the spade ring 18 contains a closed insert 70, no matter can pass through the valve 10. It will be appreciated that the open and closed inserts 70, 71 may be equipped with resilient sealing means such as gaskets to assist in sealing.

Actuation of the piston 36 causes the valve to move from the first position to the second position. In the second position the piston 36 urges the second pipe portion away from the first pipe portion 16. At the same time the piston 36 urges the ring cylinder 28 and thence the main body 40 and first pipe portion 16 away from the second pipe portion In the second position, therefore, a gap exists between the first pipe portion 16 and the second pipe portion 20. Actuation of the spade actuating means 66 when the valve is in the second position results in movement of the spade 67. In particular, the spade 67 can be moved along the spade guides 72 between an open position wherein the spade ring 18 containing the open insert 71 is between the first and second pipe portions 16, 20 and the closed spade insert 70 is within the first spade access region as shown in figure 2, and a closed position wherein the closed spade insert 70 is between the first and second pipe portions 16, 20 and the open insert 71 is within the second spade access region 62.

When the spade actuating means 66 has moved the spade 67 into the closed position, the valve 10 can then be returned to the first position to provide a seal against the outer rim of the closed spade insert It will be appreciated that the access covers 64 will enable a user to provide maintenance such as changing of inserts 70, 71 for reasons including, but not limited to, replacement of gaskets.

It will further be appreciated that the gas inlets 48 and purge valves 74 may be utilised to completely enclose the spade 67 with an inert gas whilst the valve 10 is in the second position. The pressure of this inert gas will preferably be higher than pressure within the pipes.

In a preferred embodiment of the invention a hydraulic interlock prevents operation of the spade actuating means 66 unless the valve 10 is in the second position.

The valve 10 further includes a spade centring mechanism 80. The spade centring mechanism is shown in detail in Figure 3.

The spade centring mechanism 80 consists of a resilient means such as a coil spring 82, which is connected to a guide pin 84. The guide pin 84 is mounted to the spade guide 72.

The guide pin 84 has a first end 86 which is attached to the coil spring 82, and a second end 88 remote from the coil spring 82. The spade guide 72 is mounted to the guide pin 84 intermediate the first and second ends 86, 88. The guide pin 84 is arranged such that the first end 86 is oriented towards the valve inlet 12.

The guide pin 84 includes a lip portion 90 adjacent the first end 86. The lip portion is constrained to move within a housing 92 from a first position wherein the coil spring is compressed to a second position wherein the lip portion 90 is held against an intermediate lip 94 of the housing 92. The housing 92 is mounted to the main body portion The second end 88 of the guide pin 84 is located within a recess 96 adjacent the pressure sealing bellow 38. When the valve is in the first position the inner wall of the recess 96 acts against the second end 88 of the guide pin 84, applying a force on the guide pin sufficient to compress the coil spring 82, thus maintaining the coil spring in the first position.

When the valve is moved to the second position the recess 96 moves away from the guide pin 84. This releases the compressive force on the coil spring 82, which expands to the second position wherein the lip portion 90 of the guide pin is held against the intermediate lip 94 of the housing 92. This has the effect of positively locating the spade guide 72 between the first pipe portion 16 and the second pipe portion 20. The housing 92 is dimensioned so as to place the spade guide 72 approximately midway between the first pipe portion 16 and the second pipe portion 20 when in the second position.

A gas inlet 98 is provided leading into the housing 92. This permits the housing 92 to be flooded with inert gas prior to operation.

The emergency release assembly 80 enables release of the valve 10 in the event of a failure of the actuating means 36. In this circumstance, the application of a force to the pistons 100 acts to move the valve 10 into the second position without use of the pistons 36.

Modifications and variations as would be apparent to a skilled addressee are deemed to be within the scope of the present invention.

Claims (14)

1. A sealing means having a fluid flow path and a spade having an open portion and a closed portion, the sealing means having an open position whereby the open portion of the spade is within the fluid flow path and a closed position whereby the closed portion of the spade is within the fluid flow path, the sealing means having a first position wherein the spade is prevented from moving between an open position and a closed position, and the sealing means having a second position wherein the spade is permitted to move between an open position and a closed position.

2. A sealing means as claimed in claim 1, wherein the sealing means includes a spring arranged to provide a compressive force to maintain the sealing means in the first position.

3. A sealing means as claimed in claim 2, wherein the compressive force is adjustable.

4. A sealing mains as claimed in any one of the preceding claims wherein the sealing means includes an actuating means, operation of the actuating means moving the sealing means from the first position to the second position.

A sealing means as claimed in claim 4, wherein the actuating means is a hydraulic piston.

6. A sealing means as claimed in claim 4 or claim 5, wherein the actuating means is disposed within a ring cylinder.

7. A sealing means as claim in any one of the preceding claims, wherein the spade is a substantially rectangular sliding member. 12

8. A sealing means as claimed in claim 7, wherein the spade has two spade rings at opposed ends thereof, each of the spade rings being arranged to receive an open spade insert or a closed spade insert.

9. A sealing means as claimed in claim 8, wherein when the sealing means is in the open position access is provided to the closed spade insert.

A sealing means as claimed in claim 8 or claim 9, wherein when the sealing means is in the closed position access is provided to the open spade insert.

11. A sealing means as claimed in any one of claims 7 to 10 wherein the spade is slidable, when the sealing means in the second position, in a direction substantially perpendicular to the fluid flow path.

12. A sealing means as claimed in claim 11, wherein the sealing means includes a spade centring mechanism which positively locates the spade in position.

13. A sealing means as claimed in any one of the preceding claims, wherein the sealing means includes gas inlets to enable flooding of the fluid flow path.

14. A sealing means as claimed in any one of the preceding claims, wherein the sealing means includes an emergency release mechanism whereby the supply of external pressure to the emergency release mechanism urges the sealing means into the second position. A sealing means as described hereinabove with reference to, and as shown in, the accompanying drawings. DATED THIS 2 7 TH DAY OF FEBRUARY 2004. CAMCO DRIECO INDUSTRIAL SERVICES PTY LTD By their Patent Attorneys LORD COMPANY PERTH, WESTERN AUSTRALIA.