Field of the Invention

The present invention relates to fluid treatment, in particular to apparatus for use in straining fluid in fluid piping, for example fluid in fluid circuit piping of a heating system or a cooling system.

Background of the Invention

Known heating and cooling systems comprise a fluid circuit through which a fluid circulates under pressure. An example of this type of system is a closed circuit central heating system, in which system water flows in a loop from a boiler, through a series of radiators or heat emitters, and then back to the boiler.

Systems of this type are typically manufactured from steel and other common metals. In such systems, material surfaces are exposed to the circulated fluid. A problem that is commonly associated that these systems is the corrosion of metal that is in contact with the system fluid.

System corrosion results in contamination of the circulated water with corrosion particles, such as rust, detritus and other undesirable debris. The presence of corrosion particles within the circulated liquid negatively impacts system performance and causes damage. Unless the corrosion particles are captured and removed from the contaminated circulated liquid, system components can become clogged or blocked, leading to a significant loss of system efficiency, further system deterioration from leaks, and eventually total system failure.

When the performance efficiency of a heating or cooling system reduces due to the effects of corrosion contamination, both the amount of energy required to operate the system and the amount of carbon dioxide (C02) emitted by the system increases. It is therefore desirable from economic and environmental perspectives to prevent or inhibit the detrimental effect of corrosion particles within the circulating liquid.

I A known device for use in removing corrosion particles from the circulating fluid is a strainer (also termed a pipeline strainer). The strainer is connected to the fluid circuit piping, directly in-line with the fluid flow, and functions to mechanically remove unwanted solids from the system fluid. When installed, fluid flows through a screen within the strainer, which acts as a physical filter. Particles in the system fluid that are over a certain size are trapped by the screen, and captured particles are retained within the strainer for subsequent removal.

Strainers are typically installed upstream of equipment to be protected. For example, a strainer may be installed upstream of a pump to prevent larger pieces of debris from fouling the impeller, which could result in a blockage or damage. By way of further example, a strainer may be used upstream of a boiler, a heat exchanger, or a large and/or expensive item in a system. A type of prior art strainer is known as a Y-type strainer. The body of a Y-type strainer has first and second branches providing an inlet and an outlet, and a third intermediate branch providing a pocket for a screen that intersects the fluid flow path between the inlet and outlet, such that fluid flowing through the body passes through the screen. The screen is typically provided by a strainer basket, which takes the form of a cylindrical drum made from a metal perforated sheet or mesh. In use, fluid flows into an open end of the cylindrical screen and any particles that are too big to flow through the openings, such as rust and detritus particles, are trapped inside for subsequent removal. In this way, contaminant particles over a certain size are separated from the circulating fluid as it flows through the strainer. Over time, however, the particles captured within the cylindrical screen build up and inhibit throughflow. To prevent problems arising from clogging or blocking of the screen by caught particles, routine maintenance is required to remove the collected detritus from within the strainer. However, unlike some filters, the screen can be cleaned and reused. A typical screen has openings dimensioned to prevent passage therethrough of particles having a particle size equal to or greater than 80 microns. Therefore, particles having a particle size of less than 80 microns are not prevented from flowing through the strainer and back into circulation. It is known for these smaller particles to settle in‘low flow’ areas, for example at the bottom of radiators and pipes of a heating system. Further, it is known for rust particles, which are relatively very small, to combine with scale deposits to form a sludge-like substance (generally termed sludge). This is particularly prevalent in areas of particle settlement. Sludge is a common problem within heating systems, and can block pipework and develop into large clumps in the bottom of radiators. Sludge deposits or clumps at the lower end of a radiator cause a localised reduction in heat transmission (known in the industry as a cold spot). The presence of such cold spots increases energy usage and places the system under operational strain. Summary of the Invention

According to a first aspect there is provided an accessory for use with a pipeline strainer, the pipeline strainer having a body for connection to a fluid piping inflow conduit and to a fluid piping outflow conduit, the body defining an interior chamber within which a screen collector is beatable, a fluid inlet port, and a fluid outlet port, and the body defining a fluid flow path between the fluid inlet port and the fluid outlet port that extends through the interior chamber; the accessory comprising a collar supporting a permanent magnet arrangement comprising at least one permanent magnet, the collar mountable around the body of the pipeline strainer, to position the at least one permanent magnet in the vicinity of a screen collector located within the body of the pipeline strainer.

In an example, the accessory is for use with a Y-type pipeline strainer having a first branch that comprises the fluid inlet port, a second branch that comprises the fluid outlet port, and a third branch that comprises a collector port through which a screen collector is removably beatable within the interior chamber, wherein the collar of the accessory is mountable around the third branch of the body of the Y-type pipeline strainer.

The collar may take the form of a discontinuous substantially circular band that can be snap- fitted around the third branch of the body of the Y-type pipeline strainer. In an example, the collar supports a plurality of permanent magnets.

In an example, the accessory takes the form of a clip. In an example, the accessory is removably fittable to the pipeline strainer.

In an example, the permanent magnet arrangement comprises at least one adjustable permanent magnet that is movably supported within a respective aperture of said collar such that an extent of insertion of the permanent magnet inside the collar is variable.

The or each adjustable permanent magnet may comprise an external screw thread that is co-operable with an internal screw thread of a respective aperture of the collar to movably support the permanent magnet inside the collar, the permanent magnet rotatable within the respective aperture to vary the extent of insertion of the permanent magnet inside the collar.

The or each adjustable permanent magnet may comprise an engagement arrangement co- operable with a tool for facilitating rotation of the permanent magnet within the respective aperture.

The or each adjustable permanent magnet may be removably supported within a respective aperture of the collar. According to a second aspect, there is provided a pipeline strainer provided with an accessory according to the first aspect.

According to a third aspect, there is provided apparatus arranged to be used in the treatment of fluid in a fluid circuit of a heating or a cooling system, said apparatus comprising: (i) a pipeline strainer, the pipeline strainer having a body for connection to a fluid piping inflow conduit and to a fluid piping outflow conduit, the body defining an interior chamber within which a screen collector is beatable, a fluid inlet port, and a fluid outlet port, and the body defining a fluid flow path between the fluid inlet port and the fluid outlet port that extends through the interior chamber; and (ii) an accessory according to the first aspect.

According to a fourth aspect, there is provided a method of treatment of fluid in a fluid circuit of a heating or a cooling system, comprising the steps of: (a) identifying a pipeline strainer installed in the fluid circuit of a heating or cooling system, the pipeline strainer having a body for connection to a fluid piping inflow conduit and to a fluid piping outflow conduit, the body defining an interior chamber within which a screen collector is beatable, a fluid inlet port, and a fluid outlet port, and the body defining a fluid flow path between the fluid inlet port and the fluid outlet port that extends through the interior chamber; (b) receiving an accessory according to the first aspect; and (c) mounting the collar of the accessory around the body of the pipeline strainer, to position the at least one permanent magnet in the vicinity of a screen collector located within the body of the pipeline strainer. Further particular and preferred aspects of the invention are set out in the accompanying dependent claims.

Brief Description of the Drawings

The present invention will now be more particularly described, with reference to the accompanying drawings, in which:

Figures I to 4 show a prior art strainer;

Figure 5 shows an accessory for a pipeline strainer;

Figure 6 shows the accessory of Figure 5 alongside the strainer of Figures I to 4; Figure 7 shows the accessory of Figure 5 arranged for use on the strainer of

Figures I to 4;

Figure 8 shows an accessory for a pipeline strainer, according to an alternative example;

Figure 9 shows the accessory of Figure 8 alongside the strainer of Figures I to 4; Figure 1 0 shows a feature of the accessory of Figure 8; and

Figures I I to 14 show steps in arranging the accessory of Figure 8 for use with the strainer of Figures I to 4.

Description

Illustrative embodiments and examples are described below in sufficient detail to enable those of ordinary skill in the art to embody and implement the apparatus, systems and/or processes described herein. It is to be understood that embodiments and examples can be provided in many alternate forms and the invention should not be construed as limited to the embodiments and examples set forth herein but by the scope of the appended claims.

As will be described in further detail below, an accessory for use with a pipeline strainer is provided, the accessory comprising a collar that supports a permanent magnet arrangement comprising at least one permanent magnet and that is mountable around the body of the pipeline strainer. A pipeline strainer provided with the accessory is also provided. Apparatus arranged to be used in the treatment of fluid in a fluid circuit of a heating or a cooling system, comprising a pipeline strainer and the accessory, is further provided. A method of treatment of fluid in a fluid circuit of a heating or a cooling system, comprising providing an installed pipeline strainer with the accessory, is moreover provided.

A Y-type pipeline strainer 101 is shown in Figures I to 4. The strainer 101 is suitable for use in fluid piping, for example fluid circuit piping of a heating or cooling system.

Strainer 101 comprises a body 102 for connection to a fluid piping inflow conduit and to a fluid piping outflow conduit (not shown).

The body 102 defines an interior chamber 103, a fluid inlet port 104 and a fluid outlet port 105. The body 102 defines a fluid flow path, indicated by arrow 106, between the fluid inlet port 104 and the fluid outlet port 105 that extends through the interior chamber 103. The body 102 is arranged such that fluid, such as circulating liquid of a heating or cooling system, flowing therethrough from the fluid inlet port 104 to the fluid outlet port 105 passes through the interior chamber 103. The strainer 101 may be provided with any suitable arrangement for use in connecting the body 102 to a fluid piping inflow conduit and to a fluid piping outflow conduit.

The strainer 101 comprises a screen collector 201. The screen collector 201 allows fluid to flow therethrough. The screen collector 201 is removably beatable in the body 102.

The body 102 defines a collector port 107 open to the interior chamber 103 through which the screen collector 201 can be removably inserted into the body 102. As illustrated, body 102 has a Y-shape. A first branch 108 of the Y-shape comprises the fluid inlet port 104, a second branch 109 of the Y-shape comprises the fluid outlet port 105 and a third branch I 10 of the Y-shape comprises the collector port 107. According to the illustrated arrangement, the fluid inlet port 104 and the fluid outlet port 105 are aligned, with the first and second branches 108, 109 of the Y-shape being arranged linearly, and the third branch I 10 extends outwardly from a position intermediate the fluid inlet and outlet ports 104, 105. The third branch I 10 has an external diameter I I I .

The screen collector 201 is beatable in the interior chamber 103, within the fluid flow path 106. The screen collector 201 is beatable within the body 102 such that fluid flowing through the strainer 101 from the fluid inlet port 104 to the fluid outlet port 105 passes through the screen collector 201.

The strainer 101 is arranged to mechanically capture particles having a particle size equal or greater than a predetermined size and to magnetically capture magnetic particles having a particle size less than the predetermined size. In an example, the predetermined size is 80 microns and particles having a particle size of equal to or greater than 80 microns are captured by the screen collector 201. It is to be appreciated that the predetermined size may vary between applications. The screen collector 201 can be selected to screen particles of a different particle size, for example depending on the particular intended application of the strainer 101.

In this illustrated example, the screen collector 201 is a strainer basket, which comprises a substantially tubular body 202 having an open fluid inflow end 203.

The screen collector 201 is beatable within the fluid flow path 106 such that fluid flowing from the fluid inlet port 104 towards the fluid outlet port 105 enters the substantially tubular body 202 through the open fluid inflow end 203. In this example, the substantially tubular body 202 is substantially cylindrical, with a substantially circular shaped cross section; however, it is to be appreciated that in alternative examples the substantially tubular body 202 may have any suitable alternative cross-sectional shape. In this example, the screen collector 201 defines a plurality of openings, such as aperture 204, that are each dimensioned to capture particles having a particle size equal to or greater than 80 microns. The screen collector 201 may however be arranged to capture particles of any suitable alternative size. The screen collector 201 is arranged to separate particles of a certain size from fluid flowing through the strainer 101.

In this example, the screen collector 201 comprises a perforated metal sheet screen. It is to be appreciated that the screen collector could comprise any suitable alternative type of screen, for example an expanded metal sheet screen, a welded wire mesh screen, or a woven wire mesh screen. Further, the screen may be made from any suitable material or combination of materials, and is not limited to being made from metal.

The screen collector 201 may define any suitable number of openings 204, which may be any suitable size and shape and which may include openings of different sizes and/or shapes.

The body 102 of the strainer 101 is made from a non-magnetic material or combination of non-magnetic materials. In an example, the body 102 is made from a non-magnetic metal, for example stainless steel or brass. The body 102 may however be made from any suitable non-magnetic material or combination of non-magnetic materials.

Referring to Figure I , body 102 comprises an internal annular shoulder, indicated at 1 12, against which the substantially tubular body 202 of the screen collector 201 abuts when located within the interior chamber 103 for use; the interior chamber 103 is then, in effect, divided into three zones - a first zone upstream of the screen collector 201 , a second zone occupied by the substantially tubular body 202 of the screen collector 201 and a third zone downstream of the screen collector 201.

During use of the strainer 101 , circulating fluid flowing in the fluid piping flows from a fluid piping inflow conduit (not shown), through the fluid inlet port 104 into the interior chamber 103, through the screen collector 201 and through the fluid outlet port 105 to exit the interior chamber 103 into a fluid piping outflow conduit (not shown). As the fluid flows through the strainer 101 , particles in the fluid are captured in the interior chamber 103.

Particles having a particle size that is equal to or greater than a predetermined particle size are collected by the screen collector 201.

The substantially tubular body 202 is beatable within the fluid flow path 106 such that fluid flowing from the fluid inlet port 104 towards the fluid outlet port 105 enters the substantially tubular body 202 through the open fluid inflow end 203. The screen collector 201 and the body 102 are arranged such that all the fluid entering the strainer 101 must enter the substantially tubular body 202 of the screen collector 201. Any particles in the fluid that are too big to pass through the openings 204 are mechanically captured and retained within the substantially tubular body 202 of the screen collector 201. The strainer 101 can be installed between fluid piping inflow and outflow conduits (not shown) such that the first and second branches 108, 109 of the Y-shaped body 102 are in a generally orientation along a virtual horizontal line and the third branch I 10 of the Y- shaped body 102 points downwardly from the virtual horizontal line. With this orientation, gravity assists with the retention of collected particles within the substantially tubular body 202 of the screen collector 201.

The screen collector 201 functions to remove particles, such as corrosion particles, from contaminated fluid flowing through the strainer 101 , such that fluid exits the interior chamber 103 cleaner than when it entered the interior chamber 103. Thus, using the strainer 1 01 upstream of an item of equipment functions to prevent contaminant particles from flowing to that item of equipment.

The strainer 101 may be used in a variety of different applications, for example in fluid circuit piping of a heating or cooling system, in which example the strainer is usable to remove contaminants, such as corrosion particles, from the circulating system liquid, or in fluid circuit piping of a fuel line, in which example the strainer is usable to remove contaminants from a flow of fuel, for example from a flow of petrol. An accessory for a pipeline strainer, in particular a Y-type pipeline strainer, will now be described with reference to Figures 5 to 7.

As will be described in further detail, the accessory is mountable to a strainer to provide the strainer with an additional mode of particle capturing. More specifically, the accessory provides a magnetic mode of capturing particles in addition to the existing mechanical mode of capturing particles of the strainer.

Accessory 501 is usable with strainer 101 of Figures I to 4; however, it is to be appreciated that an accessory for a strainer as described herein may be usable with a different strainer. For example, an accessory for a strainer as described herein may be usable with a strainer having a body that does not have a Y-shape.

Accessory 501 is retrofittable to strainer 101 , and can be fitted to strainer 101 when the strainer 101 is installed for use between fluid piping inflow and outflow conduits (not shown).

Accessory 501 comprises a collar 502, which supports a permanent magnet arrangement comprising at least one permanent magnet 503. The collar 502 is mountable around the body 102 of strainer 101 , to position the at least one permanent magnet 503 in the vicinity of the screen collector 201 located within the body 102.

The collar 502 of the accessory 501 is made from a non-magnetic material or combination of non-magnetic materials. In an example, the collar 502 is made from a plastics material.

In this illustrated example, the collar 502 takes the form of a discontinuous substantially circular band that can be snap-fitted around the third branch I 10 of the Y-shaped body 102 of strainer 1 01. Thus, according to the present embodiment, the accessory 501 takes the form of a clip. In this example, the accessory 501 is removably fittable to the strainer 101. It is to be appreciated that the collar 502 may have any suitable diameter, depending on the diameter of the branch of the strainer to which the accessory 501 is to be fitted. The accessory 501 is shown in Figure 5 clipped around the third branch I 10 of the Y- shaped body 102 of strainer 101 , which houses the screen collector 201 , with the collar 502 extending around, and in contact with, the external circumference of the branch I 10. In this illustrated example, the collar 502 supports first and second permanent magnets 503, 504. In the shown example, the first and second permanent magnets 503, 504 are supported in a diametrically opposed arrangement.

As can be seen in Figures 3 and 4, the collar 502 has an internal surface 505 and an external surface 506, each of the permanent magnets 503, 504 has an obverse face, such as obverse face 507 of permanent magnet 504, and a reverse face, such as reverse surface 508 of permanent magnet 503, and, in this example, the first and second permanent magnets 503, 504 are supported by the collar 502 such that the obverse face 507 of each the first and second permanent magnets 503, 504 is exposed and substantially flush with the internal surface 505 of the collar 502. Thus, when the accessory 501 is fitted directly on the strainer 101 , there is no obstruction between the external surface of the body 102 and the obverse face 507 of each of the first and second permanent magnets 503, 504.

As shown, in this example, the first and second permanent magnets 503, 504 are supported by the collar 502 such that the reverse face 508 of each the first and second permanent magnets 503, 504 is exposed and substantially flush with the external surface 505 of the collar 502. In an alternative example, the reverse faces 508 of the first and second permanent magnets 503, 504 may be covered rather than exposed. In this illustrated example, the obverse and reverse faces 507, 508 of each of the first and second permanent magnets 503, 504 have a substantially circular shape.

In this example, each of the first and second permanent magnets 503, 504 is a rare-earth magnet. However, each permanent magnet may be an alternative type of magnet, for example a ferrite or AINiCo type magnet.

It is to be appreciated that the collar 502 of the accessory 501 may support any suitable number of permanent magnets, each having any suitable shape and dimensions, in any suitable arrangement. The or each permanent magnet may be supported by the collar 502 in any suitable manner. A permanent magnet may be framed by, embedded into or housed within the collar 502. Thus, material of the collar 502 may or may not be present between a permanent magnet of the accessory 501 and a pipeline strainer when the accessory is arranged for use with the pipeline strainer.

The collar 502 of the accessory 501 may be formed from a unitary component or from multiple elements. The clip form of the illustrated accessory 501 enables the collar 502 to be simply pushed onto, and pulled from, the strainer 101.

According to the shown example, the accessory 501 further comprises a manually-grippable element 509 to facilitate convenient handling of the accessory 501. The manually-grippable element 509 can be used during the fitting of the accessory to a strainer and, as appropriate, temporary removal of the accessory 501 from the strainer.

A substantially central axis AA through collar 502 is shown in Figure 3, which provides a reference axis for radial (R) and axial (A) directions of the collar 502. The collar 502 may have any suitable depth dimension in the axial direction and any suitable internal radius dimension in the radial direction.

In the shown arrangement, the manually-grippable element 509 takes the form of a rigid tab that extends radially outwardly from the external surface 506 of the collar 502, and that extends, in the axial direction, between first and second sides 5 10, 5 I I of the collar 502.

In an example, the collar 502 has an internal diameter that is substantially equal to the external diameter of the branch of the strainer on which the accessory 501 is to be used, to ensure a substantially continuous line of contact, in the radial direction, between the internal surface 505 of the collar 502 and the external surface of the branch of the strainer. The accessory 501 fitting tightly around the strainer serves to optimise the application of the magnetic field provided by the magnet or magnets supported by the collar 502 to the interior of the strainer. The collar 502 has opposed ends 5 12, 5 1 3, with a gap G therebetween. Each end 5 12, 5 1 3 may have any suitable shape. The manually-grippable element 509 is diametrically opposed to the gap G. Thus, according to the illustrated example, the collar 502 has a first arm section 5 14 extending in one radial direction from the manually-grippable element 509 and comprising the first permanent magnet 503 and the first end 5 12 and a second arm section 5 15 extending in the opposite radial direction from the manually-grippable element 509 and comprising the second permanent magnet 504 and the second end 5 1 3. It is to be appreciated that the angular extent of the gap G may vary between applications. Thus, the angle through which the collar 502 extends around an external circumference of the strainer 101 may vary between applications.

The thickness of the collar 502, in the radial direction, may also vary between applications. According to this specific example, the collar 502 has an‘at rest’ shape (shown in Figure 5), towards which the collar 502 is biased. As the accessory 501 is clipped onto the strainer 101 , the ends 5 12, 5 1 3 of the collar 502 are pushed apart as the external diameter of the branch I 10 is approached, causing the first and second arm sections 5 14, 5 15 of the collar 502 to open outwards, and as the ends 5 12, 5 1 3 of the collar 502 are moved beyond the position of the external diameter of the branch I 10, the ends 5 12, 5 1 3 of the collar 502 return towards each other and the first and second arm sections 5 14, 5 15 of the collar 502 close inwards.

By virtue of the permanent magnet arrangement comprising at least one permanent magnet 503, the accessory 501 features a magnetic field strength that is sufficiently large enough to, when fitted on the third branch I 10 of the Y-shaped strainer 101 , penetrate the external wall of the body 102 and the screen collector 201 and into the fluid flowing within the interior chamber 103. In use, the accessory 501 functions to attract and separate magnetic particles from fluid flowing through the strainer 101. Referring to Figure 6, when accessory 501 is fitted on strainer 101 , and fluid is flowing through strainer 101 , particles in the fluid can be captured in the interior chamber 103 by each of two different modes of particle capture. Particles having a particle size that is equal to or greater than a predetermined particle size are mechanically collected by the screen collector 201. Magnetic particles are magnetically attracted by the at least one permanent magnet of the accessory 501 and remain in a retained condition while the accessory 501 remains in use with the strainer 101.

Thus, in this specific example, particles having a particle size equal or greater than 80 microns are captured by the screen collector 201 and particles having a particle size of less than 80 microns are captured under the magnetic field applied by the accessory 501. It is to be appreciated however that the accessory 501 may also attract particles having a particle size that is equal to or greater than 80 microns. During normal operation of the strainer 101 , particles having a particle size equal to or greater than a predetermined size that enter into the strainer 101 with the circulating fluid are captured by the screen collector 201. These mechanically captured particles are retained in the interior chamber 103 until subsequently removed. Further, during normal operation of the strainer 101 , magnetic particles are attracted by the accessory 501 and collect within the interior chamber 103. Magnetic particles having a particle size equal to or greater than the predetermined size collect within the screen collector 201 only; magnetic particles having a particle size less than the predetermined size may collect within the screen collector 201 (for example, against the inside wall surface thereof) or against an internal wall surface of the third branch I 10 of the Y-shaped body 102. These captured particles are retained in the interior chamber 103 until subsequently removed.

Routine maintenance of the strainer 101 and accessory 501 combination shown in Figure 7 will now be described. To remove material collected from the circulating fluid by the strainer 101 , the strainer 101 is isolated from the fluid flow to stop circulation of fluid into the strainer 101. Accessory 501 is removed from around the branch I 10 housing the screen collector 201 , to remove the magnetic field previously applied by the permanent magnet arrangement of the accessory 501. The collector port 107 is opened to allow removal of the screen collector 201 from within the body 102. The screen collector 201 is withdrawn through the collector port 107 and rinsed clean of captured magnetic and non-magnetic particles. The internal wall surfaces of the third branch I 10 of the body are rinsed clean of captured magnetic particles. The cleaned screen collector 201 is then replaced in the interior chamber 103. The collector port 107 is then be closed. The accessory 501 is replaced on the body 102. The strainer 1 01 may then be opened back to the system flow. It is to be appreciated that the above-mentioned steps may be performed in any suitable chronological order.

An accessory for a pipeline strainer, in particular a Y-type pipeline strainer, according to a further example will now be described with reference to Figures 8 to 1 4.

Accessory 801 is similar to accessory 501 but features a permanent magnet arrangement that differs from the permanent magnet arrangement of accessory 501.

Accessory 801 comprises a collar 802 that supports a permanent magnet arrangement comprising at least one adjustable permanent magnet 803. In this illustrated example, the collar 802 supports first and second adjustable permanent magnets 803, 804.

As shown, the collar 802 has an internal surface 805 and an external surface 806. Each of the first and second adjustable permanent magnets 803, 804 is movably supported within a respective aperture 807, 808 of the collar 802 such that an extent of insertion of the permanent magnet 803, 804 inside the collar 802 is variable. According to this illustrated example, the apertures 807, 808 extend all the way through the collar 802, from the external surface 806 to the internal surface 805.

Each of the adjustable permanent magnets 803, 804 has a first end, such as first end 809 of adjustable permanent magnet 804, and a second end, opposite the first end, such as second end 810 of adjustable permanent magnet 803. Each of the adjustable permanent magnets 803, 804 is movably supported within a respective aperture 807, 808 of the collar 802 such that the adjustable permanent magnet 803, 804 is movable in each of the opposite radial directions indicated by arrow R. With each of the adjustable permanent magnets 803, 804 being movably supported by the collar 802 in this way, an innermost end thereof, such as the first end 809 of adjustable permanent magnet 804 in the shown arrangement, can be inserted towards and withdrawn away from a centre point C of the accessory 801. According to the present example, each adjustable permanent magnet 803, 804 comprises an external screw thread, such as external screw thread 81 1 of adjustable permanent magnet 804, that is co-operable with an internal screw thread (not shown) of a respective aperture, such as aperture 808, of the collar 802 to movably support the adjustable permanent magnet inside the collar 802, the adjustable permanent magnet 803, 804 rotatable within the respective aperture 807, 808 to vary the extent of insertion of the adjustable permanent magnet 803, 804 inside the collar 802.

In this Figure, the collar 801 is shown in an‘at rest’ condition, in which the collar 802 has an internal diameter 812.

As indicated in Figure 9, collar 801 is usable on pipeline strainer 101.

Referring now to Figure 1 0, each of the adjustable permanent magnets 803, 804 comprises an engagement arrangement, such as engagement arrangement 1001 of adjustable permanent magnet 803, that is co-operable with a tool, such as tool 1002, for facilitating rotation of the permanent magnet 803, 804 within the respective aperture 807, 808. According to this illustrated example, engagement arrangement 1001 comprises a hexagonal socket and tool 1002 is a hex key. It is to be appreciated however that the engagement arrangement and the tool may each be any suitable type.

As indicated in this Figure, according to the shown arrangement, each of the adjustable permanent magnets 803, 804 is removably supported within a respective aperture 807, 808 of collar 802. This feature allows the adjustable permanent magnets 803, 804 to be removed and subsequently replaced or substituted for an alternative permanent magnet. For example, it may be desirable to exchange an adjustable permanent magnet 803, 804 with another having a different magnetic strength and/or length. In this example, the adjustable permanent magnets 803, 804 are each received directly within a respective aperture 807, 808. It is to be appreciated that in an alternative example, an adjustable permanent magnet may be received within a support element that is movable within a respective aperture of the collar to vary the extent of insertion of the adjustable permanent magnet inside the collar.

Steps in a method of mounting the accessory 801 to a pipeline strainer 101 will now be described with reference to Figures I I to 1 4.

In the illustrated scenario of Figure I I , when in the shown‘at rest’ condition, the internal diameter 812 of the collar 802 is greater than the external diameter I I I of the third branch I 10 of the body 102 of pipeline strainer 101 ; however, the gap G between the ends of the collar 802 is less than the external diameter I I I of branch I 10 of the body 102 of pipeline strainer 101. The collar 802 is made from a material, such as a plastics material, that allows the accessory 801 to be mounted onto the body 102 of pipeline strainer 101 with a snap- fit action.

The accessory 801 is shown in this Figure with the adjustable permanent magnets 803, 804 in a withdrawn position, such that the adjustable permanent magnets 803, 804 do not project from the internal surface 805 of the collar 802 towards centre point C.

As indicated by arrow I 103, the accessory 801 can be push-fit onto the pipeline strainer 101. In Figure 1 2, the accessory 801 is shown with collar 802 positioned around the third branch I 10 of the body 102 of the pipeline strainer 101. The adjustable permanent magnets 803, 804 may now be rotated, as illustrated in Figure 1 3, to cause the adjustable permanent magnets 803, 804 to move inwards into respective positions in which the adjustable permanent magnets 803, 804 project from the internal surface 805 of the collar 802, as illustrated in Figure 1 . It is to be appreciated that with the collar 802 in the‘at rest’ condition, positioning the adjustable permanent magnets 803, 804 to extend inwardly from the internal surface 805 of the collar 802 effectively reduces the internal diameter of the collar 802. More specifically, when the adjustable permanent magnets 803, 804 extend inwardly from the internal surface 805 of the collar 802, the distance between the opposed innermost ends of the adjustable permanent magnets 803, 804 is less than the‘at rest’ internal diameter 812.

The ability to vary the extent of insertion of one or more adjustable permanent magnets 803, 804 inside the collar 802 allows the accessory 801 to be used on pipeline strainers having different external diameters. The collar 802 can be used on a pipeline strainer having an external diameter that is less than the‘at rest’ internal diameter 812 of the collar 802 and one or more of the adjustable permanent magnets 803, 804 can be adjusted to extend inwardly of the collar 812 to tighten the accessory 801 onto the pipeline strainer. Preferably, each of the adjustable permanent magnets 803, 804 is moved into a position that is associated with the collar 802 being positioned substantially concentrically around the pipeline strainer. Further, the ability to move one or more adjustable permanent magnets 803, 804 into a position that effectively reduces the‘at rest’ internal diameter 812 of the collar 812 enables the collar 812 to be mounted to a pipeline strainer in a tensioned condition.

By comparison, with the permanent magnets of accessory 801 being adjustable, the permanent magnets of accessory 501 are fixed. At least the following benefits are associated with the present invention:

- When the accessory (magnetic clip) is installed, particles equal to or greater than a predetermined size are removed by the screen collector (strainer basket) and particles less than a predetermined size are removed by the accessory (magnetic clip) - The accessory (magnetic clip) can be installed onto new strainer installations or can be retro-fitted onto existing strainer installations

- The accessory (magnetic clip) can be manufactured in various sizes to suit different sizes of strainers e.g. ½” to 12” in diameter to suit differing pipework requirements - The accessory (magnetic clip) can have a larger number of magnets embedded within it to provide a greater magnetic strength for bigger sized strainers

- Magnetic particles are captured in addition to particles equal to greater than a particular size, which cleans the system flow more quickly

- The capturing of magnetic particles that are smaller in size than the particles captured mechanically reduces the quantity of unwanted particles in the flowing fluid, which provides cleaner fluid flow

- The capturing of smaller particles reduces the number of particles dropping out of suspension within the system flow into low flow areas, which prevents detritus build up and clumping and, in the application of a heating system, reduces the risk of sludge and cold spots

- The capturing of more particles from the system water improves the operational efficiency of the system (helps achieve the original design efficiency) and reduces the risk of component damage and system failure, which reduces energy and maintenance costs and reduces carbon dioxide (C02) emissions

A method of treating fluid of fluid piping in accordance with the present disclosure comprises the step of receiving an accessory for a strainer as described herein and fitting the received accessory to a strainer. The method may involve identifying a strainer installed in fluid piping and fitting the received accessory thereto. The fluid piping may be fluid circuit piping of a heating system or of a cooling system.

The present disclosure provides apparatus for fluid treatment, comprising an accessory for use with a pipeline strainer. The present disclosure also provides a method of fluid treatment, comprising the step of providing a pipeline strainer with the accessory. The present disclosure further provides a pipeline strainer provided with the accessory.

In accordance with the present disclosure, an accessory for use with a Y-type pipeline strainer is provided, the accessory comprising a collar supporting a permanent magnet arrangement comprising at least one permanent magnet, the collar arranged to be clipped onto a branch of a Y-type pipeline strainer, the branch for housing a screen collector, whereby, in use, the accessory attracts magnetic particles in fluid flowing through the screen collector of the Y-type pipeline strainer. Thus, the use of the accessory of the Y-type pipeline strainer provides the Y-type pipeline strainer with a magnetic particle capturing mode (capturing particles using a magnetic field) in addition to the existing mechanical particle capturing mode (capturing particles using a screen). Preferably, the accessory takes the form of a clip that is arranged to be repeatedly snap-fitted around the exterior circumference of the branch of the Y-type pipeline strainer.

The accessory may have any suitable shape and dimensions. The permanent magnet arrangement of the accessory may comprise any suitable number of permanent magnets. The permanent magnet arrangement may comprise a plurality of permanent magnets of the same type or of different types. A plurality of permanent magnets of the permanent magnet arrangement of the accessory may comprise all fixed, all adjustable permanent, or a mix of at least one fixed and at least one adjustable permanent magnet.

Although illustrative embodiments and examples of the invention have been disclosed in detail herein, with reference to the accompanying drawings, it is to be understood that the invention is not limited to the precise embodiment and examples shown and/or described and that various changes and modifications can be effected therein by one skilled in the art without departing from the scope of the invention as defined by the appended claims.