GB2598716A

GB2598716A - Flow meter

Info

Publication number: GB2598716A
Application number: GB2013570.3A
Authority: GB
Inventors: Nicholas Whiteley Paul; Timothy Northcliffe Richard
Original assignee: Aalberts Integrated Piping Systems Ltd
Current assignee: Aalberts Integrated Piping Systems Ltd
Priority date: 2020-08-28
Filing date: 2020-08-28
Publication date: 2022-03-16
Also published as: GB202013570D0

Abstract

A commissioning valve comprises a flowmeter 1 and a control valve 11 releasably coupled together. The flowmeter and control valve are rotatable relative to each other, figs 6-9. Flow meters with male fastenings fig. 5 and female fastenings figs 21-24 are disclosed. The male fastener consists of a securing nut 2, fig. 6, with a screw thread 3 fig. 1 on its outer surface. The flow meter 1 and a pressure independent control valve (PICV) 11 fasten together via a complementary screw thread of the PICV 11 and the screw thread 3. The securing nut 2 and a venturi 6 of the flow meter 1 being secured into a tube of the PICV 11. Since the PICV 11 is fastened to the securing nut 2, which is rotatable within its recess with respect to the rest of the flow meter 1, the rest of the flow meter 1 (and in particular pressure taps 8) can be rotated with respect to the control valve PICV 11 (and the securing nut 2). The securing nut 2 can form part of the flow meter fig. 5 or part of the control valve.

Description

Flow Meter

Technical Field of the Invention

The present invention relates to a flow meter, a control valve, a commissioning valve formed of a flow meter and a control valve and a method of making a commissioning valve.

Background to the Invention

In pipe systems it is necessary to control the flow through the system at particular points, so as to adjust the rate of flow. It is also necessary to measure the flow of a fluid through the pipe system, so a user knows how the rate should be adjusted.

The flow can be controlled via a control valve forming part of the pipe system, while the flow can be measured via a flow meter of the system. Control valves are often pressure independent control valves (PICV). A flow meter can comprise a venturi or an orifice plate.

Often, the flow through the pipe system will need to be adjusted to a particular flow rate. Accordingly, it is advantageous if the flow meter and control valve are built together in the form of a commissioning valve, since then the flow rate can be measured at the point of control and the flow rate can be adjusted more precisely.

A control valve can work across a large range of flow rates. In contrast, a flow meter works across a much smaller range of flow rates. As such, a manufacturer must supply a range of commissioning valves to cover a particular range of flow rates, even if the control valve part of each commissioning valve would work across the entire range. This increases costs for a manufacturer. In addition, a user will need to swap out the commissioning valve if the flow rate of the pipe system changes such that it exceeds the range of the flow meter part (even if it doesn't exceed the range of the control valve part).

Further to the above, most commissioning valves comprise a tube with test points (for the flow meter part) and a control wheel (for the control valve part) projecting perpendicularly from the tube. In pipe systems in confined spaces, it can be difficult to integrate commissioning valves due to these projecting components.

Embodiments of the present invention seek to at least partially overcome the above described disadvantages.

Summary of the Invention

According to a first aspect of the present invention there is provided a flow meter comprising a fastening element operable to releasably fasten into a control valve and thereby connect the flow meter and the control valve together to form a commissioning valve.

By having a flow meter comprising a fastening element which can be releasably fastened to a control valve, a commissioning valve can be built from the most appropriate flow meter and control valve. Accordingly, a manufacturer need only make the flow meter for each smaller range of flow rates rather than a whole commissioning valve. This reduces manufacturing costs. In addition, a user can remove and replace just a flow meter which forms part of a commissioning valve if the range of flow rates for the pipe system changes.

The flow meter may comprise one or more test points through which a flow of a fluid through the flow meter can be measured, wherein the fastening element is rotatable relative the test points. The or each test point may be a pressure tap.

The fastening element being rotatable relative the test points allows the position of the test points to be moved with respect to the rest of the pipe system independently of the control valve and its projections. This makes installation easier, especially in systems in confined spaces.

The fastening clement may be rotatable about a central axis through the fastening clement, the central axis extending along a direction of a flow of a fluid within the fastening element.

Often a test point (or other components of the fastening element) project in a direction perpendicular the flow of a fluid through the flow meter. By rotating about this direction of flow, the projections can take any position in 360 degrees. This feature further eases installation.

The flow meter may comprise a tube along which a fluid can flow, wherein the fastening element is rotatable relative to the tube. Each test point may be connected to the tube to measure the flow of fluid through the tube at the test points.

The fastening element being rotatable relative the tube means the position of elements of the flow meter connected to the tube (such as test points or other projecting components) can be adjusted relative the fastening element and accordingly the control valve to which the fastening element fastens the flow meter. This makes installation easier, especially in systems in confined spaces.

The tube may comprise an outer surface. The test points may extend through and away from the outer surface. The test points may extend in a direction which has at least a component perpendicular a direction of flow of a fluid within the flow meter.

The fastening element may be rotatably fitted to the tube, thereby allowing the fastening element to rotate relative the tube. When the test points are connected to the tube, the (listening element may he rotatably fitted to the tube to allow the (listening clement to rotate relative the test points and the tube. The fastening clement may be a securing nut. The fastening element may comprise a screw thread via which it is operable to fasten to the cooperating element. The fastening element may comprise an outer surface, which comprises the screw thread. Part of the outer surface of the fastening element may consist of the screw thread. The securing nut may have a head and a shank. The shank may comprise the screw thread.

The flow meter may comprise a recess within an outer surface. The securing nut may be rotatably fitted within the recess. The securing nut may be secured in the recess. The flow meter may comprise a venturi. Each test point may connect to and extend from the venturi at different positions along a length of the venturi, the test points being operable to measure a flow of a fluid through the venturi. A first test point may connect at a position along the length of the venturi where the diameter of the venturi is smallest. A second test point may connect at a position along the length of the venturi where the diameter of the venturi is larger than its smallest diameter.

The test points may be fastened to the tube. The test points may be fastened into the tube. The test points may be releasably fastened to the tube. The test points may extend through a part of the tube. The test points may extend away from the tube. Each test point may comprise a fastening element and the tube may comprise respective cooperating elements, wherein the test points are fastened to the tube by fastening each test point fastening element to the respective tube cooperating element. Each test point fastening element may comprise a screw thread, and the respective tube cooperating elements may comprise complementary screw threads.

The tube may comprise a plurality of fittings extending from the circular surface of the cylinder, each fitting comprising a respective tube cooperating element of a test point and the respective test point fastened into the fitting. Each fitting may extend from an axial position along a central axis of the tube. Each fitting may extend from the same radial position around the central axis of the tube. Each fitting may be a socket. Each socket may be cylindrical.

The venturi may be fastened to the tube. The venturi may be fastened into the tube. The venturi may be fastened to a first end of the tube. The venturi may be fastened into the first end of the tube. The venturi may be releasably fastened into the tube. The venturi may comprise a fastening clement and the tube may comprise a respective cooperating element, the venturi fastened to the tube by the venturi fastening element fastening to the respective tube cooperating element. The venturi fastening element may comprise a screw thread, and the respective tube cooperating element may comprise a complementary screw thread.

The tube may comprise a pipe cooperating element operable to receive a pipe and connect the flow meter to the pipe. A second end of the tube may comprise the pipe cooperating element. The second end of the tube may consist of the pipe cooperating element. The pipe cooperating element may be a pipe socket.

The fastening element may be secured in its fitting between the tube and the venturi. The venturi may comprise an outer surface and a protrusion extending from the outer surface, the recess in the pipe formed between the protrusion and the tube. The venturi may be cylindrical and the protrusion may extend from a circular surface of the venturi. The protrusion may extend perpendicular a direction of a flow of fluid through the venturi. The protrusion may extend from an end of the venturi. The other end of the venturi may be fastened to the tube. The protrusion may extend from the entire rim of the end of the venturi. The protrusion may be a head.

The fastening element may be secured against the end of the tube. The screw thread may extend away from the end of the tube.

One or more of the fastening elements may be a male fastener. One or more of the cooperating elements may be a female fastener. One or more of the fastening elements may be a section with a screw thread. One or more of the cooperating elements may be a slot operable to receive the section, the slot having a cooperating screw thread.

The fastening element may be releasably fitted to the rest of the flow meter. The fastening element may be releasably fitted to the tube. The fastening element may be releasably secured in its fitting between the venturi and the tube. The fastening element may comprise a grip via which a user can hold the fastening element and apply force to the flow meter. The head of the securing ring may be non-circular, with a non-circular perimeter surface forming the grip. The head of the securing ring may be a polygon, with a polygon perimeter surface. The head of the securing ring may be hexagonal, with a hexagonal perimeter surface.

The fastening element may he integrally formed with the tube. The tube may comprise an inner body and an outer sleeve, the inner boy within the outer sleeve. The outer sleeve may comprise the test points. The test points may be fastened into the outer sleeve. The outer sleeve may be rotatable relative to and about the inner body. The inner body may comprise the venturi. The venturi may be fastened into the inner body. The inner body may comprise the pipe socket. The fastening element may be integrally formed with the inner body. The inner body and outer sleeve may be cylindrical. The outer sleeve may encircle part of the inner body. The venturi may fasten into part of the pipe socket.

The outer sleeve being rotatable relative to and about the inner body allows the test points to be rotated relative the fastening between the flow meter and a control valve, The flow meter may be arranged to form a respective pathway for a fluid between the or each test point and the centre of the tube. A first pathway may be between a first test point and a narrow section of the venturi. The first pathway may be between the firs( test point and the narrowest section of the venturi. A second pathway may be between a second test point and a wide section of the venturi. A second pathway may be between the second test point and a section adjacent the venturi.

The or each pathway may comprise respective channels, the or each channel extending at least partially around the tube and open to the respective test point. The or each channel may extend wholly around the tube. The or each channel may be formed in an outer surface of inner body. The or each channel may extend around a circumference of the inner body.

The use of channels extending around the tube as part of the pathway means the or each test point remains connected to the centre of the tube regardless of where it is rotated to about the inner body.

The outer sleeve may be fitted to the inner body to prevent axial motion between them. The inner body may comprise one or more grooves and the outer sleeve may comprise one or more projections, each projection within a respective groove, to fit the outer sleeve to the inner body. The or each projection may be formed by an indentation in the outer sleeve. The or each projection may be a wedge. When there is a plurality of wedges, each wedge may be pointed in the same direction.

The fitting of the outer sleeve to the inner body means that rotation motion between the two is less likely to accidentally move the outer sleeve axially relative to the inner body. The or each projection being an indentation means the outer sleeve can easily be slid onto the inner body and then, once in the correct position, the projections can be formed. The or each projection being a wedge means the outer sleeve can be removed and re-fitted to the inner body, by sliding the inner body over the wedge taper.

According to a second aspect of the present invention there is provided a control valve comprising a fastening element operable to releasably fasten into a flow meter and thereby connect the control valve and the flow meter together to form a commissioning valve.

By having a control valve comprising a fastening element which can be 30 releasably fastened to a flow meter, a commissioning valve can be built from the most appropriate flow meter and control valve. Accordingly, a manufacturer need only make the flow meter for each smaller range of flow rates rather than a whole commissioning valve. This reduces manufacturing costs. In addition, a user can remove aml replace just a flow meter which forms part of a commissioning valve if the range of flow rates for the pipe system changes.

The fastening element may be rotatable relative to the rest of the control valve. The fastening element may be rotatably fitted to the rest of the control valve. The fastening element may be rotatable about a central axis through the fastening element, the central axis extending along a direction of a flow of a fluid within the fastening element.

The fastening element being rotatable relative the rest of the control valve allows the position of components of the control valve (especially projections) to be moved with respect to the rest of the pipe system independently of the flow meter and its projections. This makes installation easier, especially in systems in confined spaces.

The control valve may be a pressure independent control valve.

According to a third aspect of the present invention there is provided a commissioning valve comprising a flow meter according to the first aspect and a control valve comprising a cooperating element or a control valve according to the second aspect and a flow meter comprising a cooperating element, the fastening element releasably fastened into the cooperating element and thereby connecting the flow meter and the control valve together to form the commissioning valve.

By having a flow meter or a control valve comprising a fastening element which can be releasably fastened to a cooperating element of a control valve or flow meter, a commissioning valve can be built from the most appropriate flow meter and control valve. Accordingly, a manufacturer need only make the flow meter for each smaller range of flow rates rather than a whole commissioning valve. This reduces manufacturing costs. In addition, a user can remove and replace just a flow meter which forms part of a commissioning valve if the range of flow rates for the pipe system changes.

The commissioning valve may comprise one or more test points through which a flow of a fluid through the commissioning valve can be measured, wherein the fastening element, is rotatable relative to the test points.

The flow meter and/or the control valve may have any or all of the optional features of the first and second aspects, as desired or appropriate.

According to a fourth aspect of the present invention there is provided a method of making a commissioning valve comprising the steps of providing a flow meter according to the first aspect and a control valve comprising a cooperating element or a control valve according to the second aspect and a flow meter comprising a cooperating element, and releasably fastening the fastening element into the cooperating element to connect the flow meter and the control valve together to form the commissioning valve.

By making a commissioning valve from a flow meter or a control valve comprising a fastening element which can be releasably fastened to a cooperating element of a control valve or flow meter, a commissioning valve can he built from the most appropriate flow meter and control valve. Accordingly, a manufacturer need only make the flow meter for each smaller range of flow rates rather than a whole commissioning valve. This reduces manufacturing costs. In addition, a user can remove and replace just a flow meter which forms part of a commissioning valve if the range of flow rates for the pipe system changes.

Detailed Description of the Invention

In order that the invention may be more clearly understood one or more embodiments thereof will now be described, by way of example only. with reference to the accompanying drawings, of which: Figure 1 is a perspective view of a flow meter; Figure 2 is an exploded view of the flow meter of figure 1; Figure 3 is a perspective view of a commissioning valve; Figure 4 is a side view of the commissioning valve of figure 3; Figure 5 is a cross sectional view of the commissioning valve of figure 3; Figure 6 is a second perspective view of the commissioning valve of figure 3; Figure 7 is a third perspective view of the commissioning valve of figure 3; Figure 8 is a fourth perspective view of the commissioning valve of figure 3; Figure 9 is a fifth perspective view of the commissioning valve of figure 3; Figure 10 is a second embodiment of a flow meter; Figure 11 is a third embodiment of a flow meter; Figure 12 is a fourth embodiment of a flow meter; Figure 13 is a cross section of a fifth embodiment of a flow meter; Figure 14 is a perspective view of the flow meter of figure 13; Figure 15 is a cross section of a pressure independent control valve comprising the flow meter of figure 13; Figure 16 is a perspective view of the pressure independent control valve of figure 15; Figure 17 is a cross section of a sixth embodiment of a flow meter; Figure 18 is a perspective view of the flow meter of figure 17; Figure 19 is a cross section of a pressure independent control valve comprising the flow meter of figure 17; Figure 20 is a perspective view of the pressure independent control valve of figure 19; Figure 21 is a cross section of a seventh embodiment of a flow meter; Figure 22 is a perspective view of the flow meter of figure 21; Figure 23 is a cross section of an eighth embodiment of a flow meter; Figure 24 is a perspective view of the flow meter of figure 23; Figure 25 is a close up view of a cross section of the flow meter of figure 13; and Figure 26 is a second perspective view of the flow meter of figure 13.

As shown most clearly in figure 1, the flow meter 1 comprises a male fastener. The male fastener consists of a securing nut 2 with a screw thread 3 on its outer surface. The securing nut 2 consists of a head 10 and a shank. The screw thread 3 extends along a majority of the shank, to an end of the securing nut 2. The screw thread 3 then stops, and at the other end of the securing nut 2 is the circular head 10. The securing nut 2 is secured to a tube 4. The securing nut 2 is secured against one end of the tube 4 such that the screw thread 3 extends along a direction away from the end of the tube 4.

The flow meter 1 also comprises two cylindrical sockets 5, each extending from a different axial position along the central axis through the tube but the same radial position about the central axis through the tube. A respective pressure tap 8 is secured into each socket 5. A first pressure tap 8 extends from the tube 4 perpendicular to the direction of the tube 4. A second pressure tap 8 extends from the tube 4 such that a component of its direction is perpendicular to the direction of the tube 4 and a component is parallel, the second pressure tap 8 extending towards the back of the tube 4.

The flow meter 1 comprises a venturi 6. A first end of the venturi 6 is secured into a first end of the tube 4. The securing nut 2 is fitted on the venturi 6 and secured in place in a recess formed between a ridge 7, extending from the rim of the second end of the venturi 6, and the end of the tube 4. The screw thread 3 of the securing nut 2 faces away from the venturi 6.

As shown most clearly in figure 2, the first end of the venturi 6 comprises a screw thread. The first end of the tube 4 comprises a complementary screw thread, and it is via the screw thread and complementary screw thread that the venturi 6 and the first end of the tube 4 are fastened and secured together. The pressure taps 8 also comprise screw threads and the sockets 5 complementary screw threads, such that they are fastened and secured together in the same manner.

There are sealing rings 9 between and on various components of the flow meter I. The venturi 6 has two sealing rings 9 upon and extending around into outer surface, each residing in a respective recess.

One sealing ring 9 is positioned near the first end of the venturi 6, after the screw thread of the venturi 6, such that it seals the joint between the tube 4 and the venturi 6. Another sealing ring 9 lies near the middle of the venturi, before the screw thread of the venturi 6, such that it seals the joint between the venturi 6 and the securing nut 2.

A further sealing ring 9 resides in a recess in the tube 4, the recess being positioned between the outer and inner surfaces of the tube 4 and at the end of tube 4 into which the venturi 6 is secured, such that the sealing ring 9 seals the joint between the tube 4 and the securing nut 2. Finally, a sealing ring 9 resides on the outer surface of the securing nut 2, between the screw thread 3 and the head 10, to seal the joint between the flow meter 1 and a control valve to which it is connected.

Figures 3-5 show the flow meter 1 connected to a pressure independent control valve (PICV) 11. The PICV 11 comprises a tube with a complementary screw thread within the tube, at one end. The flow meter 1 and PICV fasten together via the complementary screw thread and the screw thread 3, the securing nut 2 and the venturi 6 being secured into the tube of the PICV 11.

As shown in figure 5, at the second end of the tube 4 (the end into which the venturi 6 is not secured) the diameter of the tube expands into a pipe socket 12. The pipe socket 12 comprises a complementary screw thread, via which the flow meter 1 can be secured into a pipe system.

Figure 5 also shows that, when the pressure taps 8 are secured into the sockets and the venturi 6 is also secured in place, the pressure taps 8 are connected to the venturi 6 such that any fluid within the venturi can flow into the pressure taps 8. The first pressure tap 8 connects to the venturi 6 at the narrowest point of its diameter, whereas the second pressure tap 8 connects to the venturi 6 at a position at which the diameter is larger. Accordingly, the flow through the venturi 6 can be measured via the pressure taps 8.

The PICV 11 is fastened to securing nut 2, which is rotatable within its recess with respect to the rest of the flow meter. As such, and as shown in figures 6-9, the rest of the flow meter 1 (and in particular the pressure taps 8) can be rotated with respect to the PICV 11 (and the securing nut 2).

In other embodiments of the invention, the securing nut 2 can form part of the control valve 11 instead of the flow meter 1. In such cases, the flow meter comprises the complementary screw thread to screw thread 3.

As shown in figures 10-12, different embodiments of the flow meter 1 can have differently shaped heads 10. In the embodiment of figure 10 the head 10 is hexagonal.

This allows a user to attach and release the flow meter 1 from the respective control valve, using a spanner or similar tool on the grip formed by the outer surface of the head 10. In the embodiments of figures 11 and 12 the heads 10 remain circular, and as such die flow meter 1 and control valve must be fitted together and/or removed from each other using specialist tools, typically in a factory setting. In the case of the embodiment of figure 11, the outer surface of the head 10 is ridged, the ridges being evenly spaced apart and each running the length if the head 10. In the case of the embodiment of figure 12, the head 10 comprises circle minor sector recesses within the outer surface of the head 10. The arc of each recess extends along the circumference of the head 10.

Figures 13-16 show an alternative embodiment of a flow meter 1. In this embodiment the flow meter 1 comprises a single pressure tap 8, extending from the side outer surface of the tube 4 at an angle, angled towards the back of the tube 4. The male fastener 13 is integrally formed with the tube 4, and cannot rotate with respect to it.

Instead, to facilitate rotation of the pressure tap 8 of the flow meter 1, the tube 4 comprises two parts: an inner body 14 and an outer sleeve 15. The outer sleeve 15 is cylindrical, and encircles part of the inner body 14. The sleeve 15 is rotatable around the inner body. The fastening element is intrinsically formed with the inner body 14, while die pressure tap 8 is screwed into the outer sleeve 15, such that the pressure tap 8 can be rotated about the flow meter 1 with respect to the inner body 14 and male fastener 13.

The inner body 15 comprises the pipe socket 12. The venturi 6 comprises a male screw thread on its outer surface and is screwed into and held within the inner body 13 via this male screw thread complementing the female screw thread of the pipe socket 12. The male screw thread of the venturi 6 is much shorter than the female screw thread of the pipe socket 12, being only one turn in length, leaving space for a pipe to screw into the pipe socket 12 as well behind the venturi 6.

The pressure tap 8 connects to a channel 16 in the outer surface of the inner body 14. The channel 16 has a circular path, extending around the entirety of the circumference of the inner body 14. The channel 16 is connected to the enclosed space at the centre of the inner body 14, in which the venturi 6 is situated, by two shafts 17. The shafts are positioned on opposite sides of the inner body 14, at the top and bottom of the flow meter 1.

The ends of the venturi 6 are snug with the respective parts of the inner surface of the inner body 14, and 0-ring seals are also positioned around the ends of the venturi 6 to seal the enclosed space. Between the ends of the venturi 6 there is a gap between the outer surface of the venturi 6 and the inner surface of the inner body 14. The shafts 17 extend between the channel 16 and this gap, connecting them.

Two shafts 18 extend from the central space of the venturi, where water flows, to the gap as well, connecting them. The venturi shafts 18 are positioned on opposite sides of the venturi 6, at the top and bottom. The venturi shafts 18 connect to the narrowest section in the venturi 6.

The channel 16, shafts 17, 18 and gap form a pathway for water from the venturi's narrowest section to the pressure tap 8, allowing the pressure at the narrowest section to be measured via the pressure lap 8. Due to the circular nature of the channel 16, the pressure tap 8 is always connected to the vcnturi's narrowest section wherever it is rotated to about the inner body 14.As most clearly shown in figures 25 and 26, The inner body 14 has two grooves 19 in its outer surface, each groove 19 positioned on opposite sides of the outer surface. The end of the outer sleeve 15 is adjacent the grooves 19, covering them. There are two recesses 21 in the outer surface of the outer sleeve, each recess 20 over a respective groove 19. The recesses 20 are formed by 90 degrees cut outs of the outer sleeve, leaving a thin section of the outer sleeve 15 covering each groove 19.

Once the outer sleeve 15 is slid into position around the inner body 14, part of each thin section of the outer sleeve 15 is indented to form a wedge 21 within each groove. The thick end of each wedge 21 is towards the back of the tube 4, with the wedge tapering towards the front of the tube 4. The wedges 21 reduce the chances of the outer sleeve 15 accidentally sliding off the inner body 14, keeping the outer sleeve 15 in position as it rotates about the inner body, while still allowing it to be intentionally slid off when desired or required.

As shown in figures 15 and 16, the control valve 11 comprises two female connectors on opposite sides of the valve 11, into either of which the male fastener 13 of the flow meter 1 can fasten to form a PICV with the control valve 11. The control valve 11 comprises two pressure taps 8, each pressure tap 8 is fastened into a slot in the side of a respective female connector of the control valve 11. Each pressure tap 8 extends from the respective female connector at an angle away from the centre of the control valve 11. A respective shaft connects each pressure tap 8 to the flow of fluid through the control valve 11, and can be used to measure pressure at this wide section of the flow.

A further embodiment is shown in figures 17 to 20. the flow meter 1 being similar to the fifth embodiment of the flow meter 1 and the control valve 11 matching the control valve 11 of the first embodiment. The flow meter 1 has two pressure taps 8, rather than just one. The second pressure tap 8 is fastened into and extends from the tube 4 in the same manner as the first pressure tap 8. The second pressure tap 8 connects to a second channel 22 in the outer surface of the inner body 14. The channels 16, 22 are separated by a wall formed by the inner body, an 0-ring seal on the wall to seal the channels 16, 22 from each other. Two second shafts 23 in the inner body 14 connect the second channel 22 to the space enclosed by the inner body 14, at a position in front of the venturi 6. The second shafts 23 are positioned on opposite sides of the inner body 14, at the top and bottom of the inner body 14. The pressure at this wide section of the water flow can therefore be measured via the second pressure lap 8.

In other embodiments of the present invention the control valve 11 can have the male connector and the flow meter 1 can have the corresponding female connector. Embodiments of such flow meters 1 are shown in figures 21-24.

The one or more embodiments are described above by way of example only. Many variations are possible without departing from the scope of protection afforded by the appended claims.

Claims

CLAIMSI. A flow meter comprising a fastening clement operable to relcasably fasten into a control valve and thereby connect the flow meter and the control valve together to form a commissioning valve.
2. A flow meter as claimed in claim 1 comprising one or more test points through which a flow of a fluid through the flow meter can be measured, wherein the fastening element is rotatable relative to the test points.
3. A flow meter as claimed in either of claims 1 or 2 wherein the fastening element is rotatable about a central axis through the fastening element, the central axis extending along a direction of a flow of a fluid within the fastening element.
4. A flow meter as claimed in any preceding claim comprising a tube along which the fluid flows, the tube comprising an inner body within an outer sleeve and the outer sleeve being rotatable around the inner body.
5. A flow meter as claimed in claim 4, wherein the outer sleeve is fitted to the inner body to prevent axial movement of the outer sleeve relative the inner body.
6. A flow meter as claimed in claim 4 or claim 5, when dependent upon claim 2, wherein the tube comprises an outer surface and the test points extend from the outer surface.
7. A flow meter as claimed in either of claims 4 or 5, wherein the outer sleeve comprises the test points.
8. A flow meter as claimed in any of claims 4-7, when dependent upon claim 2, wherein the test points are fastened to the tube.
A flow meter as claimed in claim 8 wherein the test points are fastened into the tube.
10. A flow meter as claimed in either of claims 8 or 9 wherein each test point comprises a fastening element and the body comprises respective cooperating elements, and the test points are fastened to the tube by fastening each test point fastening element to the respective tube cooperating element.
11. A flow meter as claimed in any preceding claim wherein the fastening element comprises a screw thread via which it is operable to fasten to the cooperating element.
12. A flow meter as claimed in any preceding claim wherein the flow meter comprises a recess within its outer surface, and the securing nut is held within the recess.
13. A flow meter as claimed in any preceding claim comprising a venturi.
14. A flow meter as claimed in claim 13 wherein the venturi is fastened to an end of the tube.
15. A flow meter as claimed in claim 14 wherein the venturi is fastened into the end of the tube.
16. A flow meter as claimed in either of claims 14 or 15 wherein the venturi comprises a fastening element and the tube comprises a respective cooperating element, and the venturi is fastened to the tube by the venturi fastening element fastening to the respective tube cooperating element.
17. A flow meter as claimed in any of claims 13-16, when dependent upon claim 12, wherein the venturi comprises an outer surface and a protrusion extending from the outer surface, the recess in the flow meter formed between the protrusion and the tube.
18. A control valve comprising a fastening element operable to releasably fasten into a flow meter and thereby connect the control valve and the flow meter together to form a commissioning valve.
19. A control valve as claimed in claim 18 wherein the fastening element is rotatable with respect to the rest of the control valve.
20. A control valve as claimed in claim 19 comprising a tube along which the fluid flows, the tube comprising an inner body within an outer sleeve and the outer sleeve being rotatable around the inner body..
21. A control valve as claimed in either of claims 19 or 20 wherein the fastening element is rotatable about a central axis through the fastening element, the central axis extending along a direction of a flow of a fluid within the fastening element.
22. A commissioning valve comprising a flow meter according to any of claims 1- 17 and a control valve comprising a cooperating element or a control valve according to any of claims 18-21 and a flow meter comprising a cooperating element, the fastening element releasably fastened into the cooperating element and thereby connecting the flow meter and the control valve together to form the commissioning valve.A commissioning valve as claimed in claim 22 comprising one or more test points through which a flow of a fluid through the commissioning valve can be measured, wherein the fastening element is rotatable relative to the test points.A commissioning valve as claimed in either of claims 22 or 23, wherein the control valve is a pressure independent control valve.A method of making a commissioning valve comprising the steps of providing a flow meter according to any of claims 1-17 and a control valve comprising a cooperating element or a control valve according to any of claims 18-21 and a flow meter comprising a cooperating element, and releasably fastening the fastening element into the cooperating element to connect the flow meter and the control valve together to form the commissioning valve. 23. 24. 25.