GB2464835A

GB2464835A - Bleed valve

Info

Publication number: GB2464835A
Application number: GB0919071A
Authority: GB
Inventors: Kevin Hester
Original assignee: Individual
Current assignee: Individual
Priority date: 2008-11-03
Filing date: 2009-10-30
Publication date: 2010-05-05
Anticipated expiration: 2029-10-30
Also published as: GB0919071D0; GB2464835B; IES20090850A2; IE86453B1; IE20090849A1

Abstract

A bleed valve 1 for engaging a threaded bore 2 of an existing bleed valve 3 of a burner 4 of a boiler/burner unit for bleeding an oil duct 5 comprises a housing 6 terminating in a threaded spigot 7 for engaging the threaded bore 2. A threaded bore 14 extending into the housing 6 terminates in a valve seat 10 from which a communicating bore 11 extends through the spigot 7. An externally threaded carrier plug 15 engageable in the threaded bore 14 terminates at one end in a closure member 16 and at the other end in a spindle 17 with a knob 19. Rotation of the carrier plug 15 urges the closure member 16 between an isolating state abutting the valve seat 10, and a bleed state with the closure member 16 spaced from the valve seat 10 to allow air bled from the oil duct 5 to vent through the communicating bore 11 and outlet port 20.

Description

"A bleed valve" The present invention relates to a bleed valve, and in particular, though not limited to a bleed valve of the type suitable for bleeding air or other gaseous fluids from a device in which a liquid flows, and the invention also relates to a method for bleeding such a device.

Oil fired boiler/burner units are well known for use in central heating systems and air conditioning systems, and such boiler/burner units, in general, are used for heating water or air for subsequent circulation through a building. In the case of boiler/burner units used for heating air, the air, in general, is passed across the boiler of the boiler/burner unit through a duct within which the boiler is located, and in turn is ducted through the building. While in the case of boiler/burner units for heating water, the water heated by the boiler is circulated through the central heating system which comprises a plurality of radiators through which the heated water is circulated from the boiler and returned thereto for reheating. In such systems, and indeed, in any systems through which a liquid flows, air or other gaseous fluids may accumulate, and in general, such gaseous fluids accumulate at high points in the system. When the gaseous fluid is of sufficient volume to fill an entire cross-section of a bore of a pipe at a high point thereof, an airlock results, which, in general, prevents further flow of liquid through the system. In the case of water filled radiators, air commonly accumulates adjacent the top of the radiator, and thus prevents heating of the area of the radiator adjacent the accumulated air.

A further problem with airlocks arises in the case of an oil line from an oil tank to a burner of a boiler/burner unit. Air locking is particularly common when the level of oil in an oil tank drops to a level within the oil tank which permits air to enter the oil line.

Thus, when the oil tank is refilled, air in the oil line tends to accumulate and form an air lock, thereby preventing the flow of oil to the burner. In general, the air lock occurs in the burner, typically adjacent the oil inlet to the burner from the oil line. To overcome this problem, a bleed valve is located in the burner at the highest point of an oil duct therein for facilitating bleeding of air from the oil line.

In the case of radiator central heating systems, a bleed valve is located adjacent the highest point of the radiator. Similarly, in piping systems where air locks are likely to occur, a bleed valve is provided in the piping system at the relevant location.

In general, such bleed valves are provided with a threaded bore which terminates in a valve seat. A bore extends from the valve seat into the oil line, pipe or interior portion of a radiator or other device from which air or other gaseous media is to be bled. A valving element, which, in general, comprises a threaded spindle which terminates at one end in a valving member is engageable in the threaded bore and the valving member is urgeable into and out of engagement with the valve seat by rotating the threaded spindle in the threaded bore. Typically, the threaded spindle terminates at its other end in a key engaging head or a screwdriver slot for facilitating rotation of the spindle in the threaded bore. In order that the valving member at the end of the threaded spindle sealably engages the valve seat, in general, it is necessary to urge the valving member into tight abutting engagement with the valve seat. This in turn requires tightening the threaded spindle in the threaded bore, which after a number of operations of the bleed valve for bleeding the burner, the pipeline, the radiator, or other device tends to wear the threads in the threaded bore. Once the threads are worn in the threaded bore, it is no longer possible to tighten the valve spindle in the threaded bore, thereby preventing sealing of the valving member against the valve seat. At this stage, relatively complex remedial action is required. Such remedial work commonly requires welding an internally threaded sleeve onto the bleed valve and providing a valving member with an extended threaded spindle for engaging the threaded bore of the sleeve, and which extends into the existing bore to engage the valve seat of the existing bleed valve. Alternatively, where welding is not feasible, the existing threaded bore must be enlarged and re-tapped and an oversize threaded spindle provided for engaging the oversize threaded bore.

These measures are complex and cumbersome, and furthermore, are relatively expensive, since in general it is necessary to remove the component, for example the burner from the boiler/burner unit, a radiator or the like to have the necessary remedial work carried out. This further adds to the expense involved.

There is therefore a need for a bleed valve which addresses this problem.

The present invention is directed towards providing such a bleed valve, and the invention is also directed towards providing a device such as a radiator or a burner of a boiler/burner unit and a bleed valve. The invention is also directed towards providing a method for bleeding a device an interior portion of which is to be bled.

According to the invention there is provided a bleed valve comprising a housing defining a hollow interior region, a coupling means extending from the housing and adapted for releasably coupling to a device an interior portion of which is to be bled, a communicating bore extending through the coupling means for accommodating fluid bled from the interior portion of the device, the communicating bore extending from a valve seat within the hollow interior region, a valving means located in the hollow interior region of the housing, the valving means being alternately operable in an isolating state co-operating with the valve seat for sea lably closing the communicating bore, and in a bleed state permitting flow of fluid through the communicating bore to the hollow interior region between the valving means and the valve seat for facilitating bleeding of the interior portion of the device, and an outlet port from the hollow interior region for accommodating fluid therefrom.

Preferably, the valving means comprises a valve member releasably engageable with the valve seat, and ideally, the valving means is carried on a threaded valve carrier engageable with a threaded bore in the hollow interior region. Preferably, the threaded bore defines the hollow interior region.

In one embodiment of the invention the valve carrier extends from the housing for facilitating gripping thereof for rotating the valve carrier. Preferably, the valve carrier comprises a threaded plug portion, one end of which terminates in the valving means, and the other end of which terminates in a spindle extending through the housing from the hollow interior region for gripping thereof. Advantageously, the spindle terminates in a hand grip exteriorly of the housing.

In one embodiment of the invention the outlet port is independent of the threaded bore through the housing, and preferably, the outlet port extends from the hollow interior region adjacent the valve seat.

Alternatively, the outlet port is formed by the threaded bore which extends from the hollow interior region.

In one embodiment of the invention the coupling means comprises a threaded spigot extending from the housing, and preferably, the threaded spigot is adapted for engaging in a threaded bore of an existing bleed valve of the device, the interior portion of which is to be bled.

The invention also provides a device, an interior portion of which is to be bled, comprising the bleed valve according to the invention located in the device and in communication with the interior portion to be bled.

In one embodiment of the invention the device comprises a radiator of a hot water central heating system.

In an alternative embodiment of the invention the device comprises a burner of a boiler/burner unit.

The invention also provides a method for bleeding a device an interior portion of which is to be bled, the method comprising providing a bleed valve with a housing defining a hollow interior region and providing the housing with a coupling means extending therefrom adapted for releasably coupling to the device the interior portion of which is to be bled, providing a communicating bore through the coupling means for accommodating fluid bled from the interior portion of the device and providing a valve seat in the hollow interior region of the housing with the communicating bore extending from the valve seat, providing a valving means in the hollow interior region of the housing whereby the valving means is alternately operable in an isolating state co-operating with the valve seat for sealably closing the communicating bore and in a bleed state permitting flow of fluid through the communicating bore to the hollow interior region, and providing an outlet port from the hollow interior region for accommodating fluid therefrom, the method further comprising coupling the housing by the coupling means to the device the interior portion of which is to be bled with the communicating bore in communication with the interior portion of the device, urging the valving means into the bleed state for permitting fluid flow through the communicating bore to the hollow interior region for bleeding the fluid from the portion of the device.

Preferably, the valving means is operated into the isolating state on completion of bleeding of the fluid from the interior portion of the device.

Advantageously, the bleed valve is coupled to the device, the portion of which is to be bled by coupling the coupling means to an existing bleed valve of the device.

In one embodiment of the invention the coupling means comprises a spigot, and the spigot is engaged in a bore of the bleed valve of the device. Preferably, the spigot of the coupling means of the bleed valve is externally threaded for engaging corresponding threads on a bore of a bleed valve of the device the interior portion of which is to be bled.

The invention will be more clearly understood from the following description of a preferred embodiment thereof, which is given by way of example only, with reference to the accompanying drawings, in which: Fig. I is a side elevational view of a bleed valve according to the invention, Fig. 2 is a transverse cross-sectional side elevational view of the bleed valve of Fig. 1, and Fig. 3 is a transverse cross-sectional view of the bleed valve of Fig. I in use.

Referring to the drawings, there is illustrated a bleed valve according to the invention, indicated generally by the reference numeral 1, for releasably engaging a threaded bore of an existing bleed valve of a device, for example, an existing bleed valve of a burner of a boiler/burner unit, a radiator of a hot water circulating central heating system or the like for bleeding the burner or radiator. In Fig. 3 the bleed valve I is illustrated fitted into a threaded bore 2 of an existing bleed valve 3 of a burner 4 of a boiler/burner unit (not shown). Only a portion of the burner 4 is illustrated in Fig. 3. The bleed valve 3 of the burner 4 is provided for bleeding air from an oil duct 5 extending through the portion of the burner 4.

The bleed valve I according to the invention comprises a cylindrical housing 6 which terminates in a coupling means, namely, a threaded spigot 7 extending from the housing 6 for engaging the threaded bore 2 of the bleed valve 3 of the burner 4. The housing 6 may be of any suitable material, for example, metal, and may be manufactured by machining, casting or fabrication, or by any other suitable method.

The housing 6 defines a cylindrical hollow interior region 8 which defines a tapering valve seat 10 from which a communicating bore 11 extends through the threaded spigot 7 for communicating with the threaded bore 2 of the bleed valve 3, and in turn with the oil duct 5 in the burner 4.

The hollow interior region 8 of the housing 6 defines a bore 14 which is threaded and extends into the housing 6 from one end thereof and terminates in the valve seat 10.

The threaded bore 14 accommodates a valve carrier formed by an externally threaded carrier plug 15, which may be of any suitable material, and typically would be of a material similar to that of the housing 6, and may be manufactured by machining, casting, or fabrication. The carrier plug 15 terminates at one end in a valving means, namely, a tapering valving member 16, and at its other end in a spindle 17.

The spindle 17 extends from the carrier plug 15 through the threaded bore 14 and terminates in a hand grip knob 19 externally of the housing 6, for facilitating gripping and rotating thereof. Rotation of the spindle 17 and in turn the carrier plug 15 urges the carrier plug 15, and in turn the valving member 16 between an isolating state as illustrated in Fig. 2 and a bleed state illustrated in Fig. 3. In the isolating state the valving member 16 sealably engages the valve seat 10 to sealably close the communicating bore 11, and in the bleed state the valving member 16 is spaced apart from the valve seat 10 for accommodating flow of fluid, typically air, through the communicating bore 11 for in turn bleeding air from the oil duct 5 through the bore 2 of the bleed valve 3, and the communicating bore 11 into the hollow interior region 8. The valving member 16 tapers at an angle substantially similar to the tapering angle of the valve seat 10, so that the valving member 16 sealably engages the valve seat 10 when the valving member 16 is in the isolating state.

An outlet port 20 extends through the housing 6 from the hollow interior region 8 adjacent the valve seat 10 for accommodating air and other fluids bled from the oil duct 5 from the hollow interior region 8.

In use, an existing valving member (not shown) of the existing bleed valve 3 in the burner 4 is removed from the threaded bore 2 thereof, and the threaded spigot 7 of the bleed valve I is threaded into the threaded bore 2 of the bleed valve 3 and is sealably secured therein by a suitable sealant, for example, PTFE tape or flax with a sealant wrapped around the threaded spigot 7. With the carrier plug 15 tightened in the threaded bore 14 of the housing 6 with the valving member 16 in the isolating state in sealing engagement with the valve seat 10, the system into which the valve I is secured may be operated normally. When it is desired to bleed air or other gaseous fluid from the oil duct 5, the carrier plug 15 is rotated in the threaded bore 14 of the housing 6 by rotating the spindle 17 by the hand grip knob 19, for urging the valving member 16 from the valve seat 10 into the bleed state. Air or other such gaseous fluid flows from the oil duct 5 through the communicating bore 11, and in turn between the valving member 16 and the valve seat 10 and through the outlet port 20 until all such air or gaseous medium has been discharged through the outlet port 20. The hand grip knob 19 is rotated in the opposite direction for urging the valving member 16 into the isolating state in tight sealing engagement with the valve seat 10.

The advantages of the invention are many. A particularly important advantage of the invention is that the valve I according to the invention can be readily replaced with a new valve I in the event of the threads on either the carrier plug 15 or the threaded bore 14 or both being sheared due to normal wear or over-tightening of the threaded plug 15 in the threaded bore 14, thereby avoiding the need for complex remedial action which would otherwise arise if the threads of the threaded bore 2 of the bleed valve 3 were sheared due to normal wear or over-tightening of a conventional spindle in the threaded bore 2 of the existing bleed valve. Since rotation of the threaded spigot 7 of the bleed valve I in the threaded bore 2 of the existing bleed valve 3 only occurs during replacement of the bleed valve 1, little or no wear occurs in the threads of the threaded bore 2 of the existing bleed valve 3 of the burner 4.

While a particular construction of valve seat and valving member and carrier plug of the bleed valve according to the invention has been described, any other suitable valving arrangements and constructions may be used. Indeed, in certain cases, it is envisaged that instead of providing a separate outlet port from the hollow interior region, the threaded bore 14 could act as the outlet port, since once the carrier plug is loosened in the threaded bore 14, air and other gaseous fluid could pass between the threads of the carrier plug 15 and the threaded bore 14.

While the bleed valve according to the invention has been described for use with a burner of a boiler/burner unit for bleeding an oil duct in the burner, it will be readily apparent to those skilled in the art that the bleed valve according to the invention may be used in any other conventional bleed valve, for example, the bleed valve according to the invention may be used in a bleed valve of a water filled radiator, in a bleed valve of a pipeline through which a liquid flows, or in any other such device or system.

Indeed, it is envisaged, in certain cases, that instead of being provided as a retrofit bleed valve, the bleed valve may be provided as an original bleed valve, and in which case, would be adapted for releasable engagement in a bleed port from the device the interior of which is to be bled. The bleed port of the device may be provided, for example, as a threaded bore without a valve seat.

Needless to say, other coupling means besides a threaded spigot may be used for coupling the housing of the bleed valve according to the invention to the device the interior of which is to be bled.

Claims

Claims 1. A bleed valve comprising a housing defining a hollow interior region, a coupling means extending from the housing and adapted for releasably coupling to a device an interior portion of which is to be bled, a communicating bore extending through the coupling means for accommodating fluid bled from the interior portion of the device, the communicating bore extending from a valve seat within the hollow interior region, a valving means located in the hollow interior region of the housing, the valving means being alternately operable in an isolating state co-operating with the valve seat for sealably closing the communicating bore, and in a bleed state permitting flow of fluid through the communicating bore to the hollow interior region between the valving means and the valve seat for facilitating bleeding of the interior portion of the device, and an outlet port from the hollow interior region for accommodating fluid therefrom.
2. A bleed valve as claimed in Claim I in which the valving means comprises a valve member releasably engageable with the valve seat.
3. A bleed valve as claimed in Claim I or 2 in which the valving means is carried on a threaded valve carrier engageable with a threaded bore in the hollow interior region.
4. A bleed valve as claimed in Claim 3 in which the threaded bore defines the hollow interior region.
5. A bleed valve as claimed in Claim 3 or 4 in which the valve carrier extends from the housing for facilitating gripping thereof for rotating the valve carrier.
6. A bleed valve as claimed in any of Claims 3 to 5 in which the valve carrier comprises a threaded plug portion, one end of which terminates in the valving means, and the other end of which terminates in a spindle extending through the housing from the hollow interior region for gripping thereof.
7. A bleed valve as claimed in Claim 6 in which the spindle terminates in a hand grip exteriorly of the housing.
8. A bleed valve as claimed in any of Claims 3 to 7 in which the outlet port is formed by the threaded bore which extends from the hollow interior region.
9. A bleed valve as claimed in any of Claims 3 to 7 in which the outlet port is independent of the threaded bore through the housing.
10. A bleed valve as claimed in any preceding claim in which the outlet port extends from the hollow interior region adjacent the valve seat.
11. A bleed valve as claimed in any preceding claim in which the coupling means comprises a threaded spigot extending from the housing.
12. A bleed valve as claimed in Claim 11 in which the threaded spigot is adapted for engaging in a threaded bore of an existing bleed valve of the device, the interior portion of which is to be bled.
13. A bleed valve substantially as described herein with reference to and as illustrated in the accompanying drawings.
14. A device, an interior portion of which is to be bled, comprising the bleed valve as claimed in any preceding claim located in the device and in communication with the interior portion to be bled.
15. A device as claimed in Claim 14 in which the device comprises a radiator of a hot water central heating system.
16. A device as claimed in Claim 14 in which the device comprises a burner of a boiler/burner unit.
17. A burner of a boiler/burner unit comprising a bleed valve as claimed in any of Claims I to 13, a portion of the burner being substantially as described herein with reference to and as illustrated in the accompanying drawings.
18. A method for bleeding a device an interior portion of which is to be bled, the method comprising providing a bleed valve with a housing defining a hollow interior region and providing the housing with a coupling means extending therefrom adapted for releasably coupling to the device the interior portion of which is to be bled, providing a communicating bore through the coupling means for accommodating fluid bled from the interior portion of the device and providing a valve seat in the hollow interior region of the housing with the communicating bore extending from the valve seat, providing a valving means in the hollow interior region of the housing whereby the valving means is alternately operable in an isolating state co-operating with the valve seat for sealably closing the communicating bore and in a bleed state permitting flow of fluid through the communicating bore to the hollow interior region, and providing an outlet port from the hollow interior region for accommodating fluid therefrom, the method further comprising coupling the housing by the coupling means to the device the interior portion of which is to be bled with the communicating bore in communication with the interior portion of the device, urging the valving means into the bleed state for permitting fluid flow through the communicating bore to the hollow interior region for bleeding the fluid from the portion of the device.
19. A method as claimed in Claim 18 in which the valving means is operated into the isolating state on completion of bleeding of the fluid from the interior portion of the device.
20. A method as claimed in Claim 18 or 19 in which the bleed valve is coupled to the device, the portion of which is to be bled by coupling the coupling means to an existing bleed valve of the device.
21. A method as claimed in Claim 20 in which the coupling means comprises a spigot, and the spigot is engaged in a bore of the bleed valve of the device.
22. A method as claimed in Claim 21 in which the spigot of the coupling means of the bleed valve is externally threaded for engaging corresponding threads on a bore of a bleed valve of the device the interior portion of which is to be bled.
23. A method for bleeding a device an interior portion of which is to be bled, the method being substantially as described herein with reference to and as illustrated in the accompanying drawings.