GB2039655A - Branch connections to pipes - Google Patents

Abstract

A branch connection to a main service pipe for water and other fluids such as gas, especially those under pressure, uses a valve 1 with an inlet opening 4 and coaxial outlet opening 5. An externally screw threaded spigot 6 around the inlet opening 4 engages a tapped hole in the main pipe 2 of metal or, in the case of a pipe of plastics or asbestos cement, a threaded socket in a saddle clamped to the main. The valve has a valve member 8 rotatable about an axis 15 with a spherical sealing surface 9 engaging a complementary seating 10 around the inlet opening 4 to close a flow path between the inlet and outlet openings. The valve member has a diametral through passage 11 which in the valve-open position is aligned with the inlet opening 4 which and the passage 11 are smooth walled and of the same diameter. The ball valve 1 can be fitted to main pipes under pressure using existing single and double spindle drilling and tapping machines. Coupling means for connecting the branch pipe to the outlet comprises an external screw thread 22 around the outlet, a union collar 24 on the branch pipe and a union nut 23. A drilling machine can be mounted on the outlet 5 to drill plastics or asbestos cement main pipes through the open valve after the valve has been mounted on a saddle clamped to the main pipe. <IMAGE>

Description

SPECIFICATION Branch connections to pipes This invention relates to the making of branch connections to pipes, especially main water pipes in order to take off water supplies, but is also applicable to main pipes carrying other fluids under pressure, gas mains and oil pipe lines for example.

An essential requirement of a connection to a main pipe is that it should incorporate a valve, called a ferrule, so as to allow the supply to be cut-off for repairs or if it becomes redundant. Conventionally, connections are made to main water pipes of metal by using a ferrule, comprising a tubular body which is threaded externally at one end for engagement in a tapped hole in the water pipe and which is threaded internally at its other end to receive a plug that controls opening and closing of a side opening outlet which is adapted for connection to a water supply pipe. Swivel ferrules are also used in which the fixed outlet of the ferrule is replaced by an outlet that is rotatably mounted on the tubular body by a banjo joint, whereby the water supply pipe can be taken off in any direction.

These ferrules are connected to water pipes, containing water under pressure, using specially designed tapping machines. One type of machine comprises a tubular housing having an open lower end for engagement with the main water pipe, a gate valve within the housing to close the lower end, and an upper end that rotatably supports a removable spindle which can carry either a drilling and tapping tool or a ferrule. In use, the machine is clamped to the water pipe, the tool is connected to the spindle, the gate valve is opened and a hole is drilled and tapped in the water pipe. The tool is then withdrawn from the tapped hole and the gate valve closed so that the spindle can be removed, the tool replaced by the ferrule, and the spindle reinserted. The gate valve is then opened and the ferrule screwed into the tapped hole in the water pipe.In another type of machine, the gate valve is omitted and two spindles are provided instead of one, one spindle carrying the tool and the other the ferrule, and the two spindles being interchangeable within the housing so that the one can be used to drill and tap a hole and the other can be used subsequently to insert the ferrule.

It is also known to make connections to water pipes composed of plastics or asbestos cement, using a saddle that is secured to the pipe and which has a threaded collar that supports a ferrule. A special machine is provided comprising a tubular housing having an open lower end that is engaged with the collar, a valve within the housing to control communication between its upper and lower ends, and a removable spindle that can be inserted into the top of the housing and is adapted to carry a drilling tool or a ferrule plug. In use, the valve is opened and the spindle with the tool connected to it is inserted through the valve and collar and rotated to cut a hole in the pipe. The spindle is then partially withdrawn through the valve and the valve closed so that the spindle can be fully removed, the tool replaced by the plug, and the spindle re-inserted.The valve is then opened and the plug screwed into the collar to close the hole in the pipe. The machine is then removed and the ferrule body connected to the collar to complete the connection. In this state the plug valve is closed, but when it is desired to turn on the water supply the plug is screwed back out of the collar into the ferrule body.

A disadvantage with all of these known ferrules is that the provision of a plug valve therein reduces the water flow rate by virtue of the resistance caused by the internal screw thread and the sharp 900 turn into the water outlet. A further disadvantage of the penny ferrule is that the water outlet cannot be taken off in any selected direction, and although this disadvantage has been overcome with the swivel ferrule, this is only achieved by increased complexity and cost.

An object of the present invention is to provide improved means for making a connection to main pipes. The present invention consists in a branch connection to a main pipe, which connection employs a valve comprising a valve body with coaxial inlet and outlet openings, the inlet opening extending through an externally screwthreaded spigot by which the valve is mounted on the main water pipe and the valve further comprising a valve member which is rotatably mounted in the valve body and has a sealing surface to close a flow path between said openings when the valve member is in a closed position, and the valve member being shaped so as to open said flow path without intruding therein when in an open position, thereby to allow the maximum unrestricted flow through said openings.

The sealing surface of the valve member preferably lies on a sphere.

Typically, the valve is a ball valve, that is to say a valve having a ball-shaped valve member, with a diametrical bore that is aligned with said inlet and outlet openings in the open position. This flow path, at least within the inlet opening and the valve member, may be of substantially constant crosssectional area and may, again at least within the inlet opening and the valve member, be smooth-walled so that it does not reduce the water flow rate.

Further, the flow path through the valve does not turn through 90 , and although a further connection to the outlet of the valve may include an elbow or bend, this need not greatly affect the flow rate.

in particular, the flow rate improvement that can be achieved is such that a ball-valve connection having a 3/4 inch water flow path has comparable performance to that of the conventional ferrule with a 1 inch water flow path, and thus the invention allows the conventional range of 1/2 inch, 3/4 inch and 1 inch ferrules to be replaced by a single 3/4 inch ball valve connection, with consequentional savings due to rationalisation.

The reduction in diameter of the inlet opening, as compared with the 1 inch ferrule, leads to a number of different advantages related to the corresponding reduction in the diameter of the hole that has to be drilled in the main water pipe for the connection. The smaller the diameter of this hole, the less the main water pipe will be weakened and the greater will be the effective wall thickness in which the connection is threaded. Also, it has been noted that 3/4 inch holes can be formed more easily with less damage to tools than is the case with either 1/2 inch or 1 inch holes.

Afurther advantage of the ball-valve connection is that it is less prone to furring-up and is more easily cleaned than the conventional ferrule because of the lack of an internal screw thread.

Yet another advantage is that coupling means to the outlet of the ball-valve may include an elbow or bend so as to allow the water supply to be taken off in any direction perpendicular to the water flow path through the valve, this being achieved without the complexity of a swivel ferrule.

Yet another advantage is that the ball-valve can be turned on simply by rotating the valve member through 90 whereas opening of the conventional ferrule involves many turns of the plug using a special tool and means to restrain unscrewing of the ferrule from the tapped hole in which it is fitted.

The invention will now be described, byway of example only, with reference to the accompanying diagrammatic drawings in which: Figure 1 is a section on line I-I of Figure 2 of one form of branch connection to a main water pipe in accordance with the invention and employing a ball valve.

Figure 2 is a fragmentary front view in the direction of the arrow il in Figure 1.

Figure 3 is a side view on a small scale of a combined drill and tap suitable for use in making the branch connection of Figures 1 and 2.

Figure 4 is a view, partly in section, of an adaptor for holding the ball valve of Figures 1 and 2 during the making of the connection and suitable for use with a known single spindle ferrule fitting machine.

Figure 5 is a view similar to Figure 4 of an adaptor suitable for a known two-spindle ferrule fitting machine.

Figure 6 is a perspective view of a key for use with the ball valve of Figures 1 and 2.

Figures 7 and 8 are fragmentary front views of the key of Figure 6 in two positions of use.

Figure 9 is a front view of a locking member for use with the ball valve of Figures 1 and 2.

Figure 10 is a fragmentary view, partly in section, as on line X-X of Figure 2, showing the locking member in use.

Figures 11 and 12 are fragmentary views of modifications of the connection shown in Figures 1 and 2 on a section line similar to that of Figure 1.

Figure 13 is a fragmentary sectional view similar to Figures 11 and 12 of a further modification.

Figure 14 is an underside plan view of a component in Figure 13.

Figure 15 is a section on line XV-XV in Figure 16 of a drilling machine suitable for use with the ball valve of Figures 1 and 2 in making anotherform of connection according to the invention.

Figure 16 is a view in the direction of the arrow XVI in Figure 15.

The branch connection shown in Figures 1 and 2 includes a ball valve 1 screwed into a tapped hole in a main water pipe 2. The ball valve 1 has a body 3 with co-axial inlet and outlet openings 4 and 5. The inlet opening 4 extends through a spigot 6 which has a tapered, external screw-thread 7 by which it is screwed into the tapped hole in the main water pipe 2. The ball valve 1 has a valve member 8 with a spherical sealing surface 9 which is received in a part-spherical seating 10 in the part, adjacent the inlet opening 4, of a valve chamber connecting the inlet and outlet openings 4 and 5. The valve member 8 has a diametral through passage 11 equal in diameter to the inlet opening 4. Both the inlet opening 4 and the passage 11 are smoothwalled.

An O-ring seal 12 is fitted in a groove in the seating 10 around the inlet opening 4 and engages the sealing surface 9 of the valve member 8. The outlet opening 5 has an internal screw thread 13 into which is screwed a retaining ring 14 having a part-spherical surface complementary to the sealing surface 9 to engage and hold the valve member 8 on the seating 10. A seal may also be provided around the outlet opening 5 between the opening and the valve member 8. For example an O-ring may be fitted in a groove in the part-spherical surface of the retaining ring 14 to engage the sealing surface 9 of the valve member 8.

The valve member 8 is rotatably mounted in the chamber about an axis 15 and is shown in Figure 1 in the open position with its passage 11 aligned with the inlet and outlet openings 4 and 5. There is a chordal groove cut in the sealing surface 9 which is engaged by a diametral rib 16 on the end face of a drive member 17 rotatably mounted in a cylindrical hole 18 through the wall of the valve body 3. The hole 18 is counterbored where it enters the valve chamber to receive a flange 19 on the drive member 17 which is fitted into the hole 18 from inside the valve chamber before insertion of the valve member 8. The flange 19 prevents internal pressure from forcing the drive member 17 out through the hole 18.

An O-ring seal 20 prevents water leakage. At the outer end of the drive member 17 is a socket 21 of square cross-section to enable the drive member 17, and through it the valve member 8, to be turned through 90 from the position shown in Figure 1 so that the passage 11 is at right angles to the axis of the inlet 4 which in this new position is closed by the sealing surface 9.

Coupling means is required to connect the outlet 5 of the valve to the branch pipe, the part of which between the valve 1 and the underground stop-cock for the premises is known to water supply authorities as the communication pipe and the part between the stop-cock and the premises as the service pipe.

In Figure 1 the coupling means comprises an external screw-thread 22 on the body of the valve around the outlet 5, a union nut 23 to be screwed onto the thread 22 and a union collar 24 which has an external annularflange 25 to be engaged by an internal annular flange 26 on the union nut 23. The union collar 24, which is shown in half section in Figure 1, may be provided with any of a variety of internal screw-threads 27 to suit the external thread of the pipe 28 to be connected by the coupling means. Instead of the pipe 28 an elbow or bend may be screwed into the inner collar and instead of the union collar 24 some other form of known coupling component may be provided on the end of the branch pipe to be engaged by the flange 26 of the union nut.An O-ring 29 or other suitable sealing washer is interposed between the union collar 24, or its equivalent, and a recess 30 surrounding the outlet opening Sin order to seal the joint.

Alternatively, the union nut may be formed integrally with the valve body, in which case the pipe 28 or elbow or bend is screwed into the thread of the fixed union nut; or the pipe 28 or elbow or bend may be screwed direct into the internal screw thread 13.

The branch pipe connection of Figures 1 and 2 could be fitted to the main water pipe using the known types of single and double spindle machine described above, the ball-valve 1 replacing the ferrule in the second stage of the fitting operation.

Figure 3 shows a conventional combined drill and tap 31 as used with known machines to drill and tap the hole in the water main. The drill and tap 31 has a taper shank 32 to suit the socket of the drive spindle 33 (Figure 4) of the machine. When the tapped hole has been made the drill and tap 31 is replaced by an adaptor 34 (Figure 4) which has a shank 35 similar to the shank 32 and an externally screw-threaded nose 36 which screws into the internal thread 13 to hold the ball-valve 1 and enable it to be screwed by the machine into the tapped hole made in the main water pipe.

The valve-holding spindle of the previouslydescribed double spindle machine has an internally screw threaded socket. Figure 5 shows a suitable adaptor 37 for the spindle, shown at 38, of a double spindle machine. One end of the adaptor 37 is threaded to suit the socket of the spindle 38 and the other end to screw into the thread 13 of the ball-valve 1.

The ball-valve 1 is fitted to the water main with the valve member in the closed position. After its outlet 5 has been connected to the communication pipe, stock-cock and service pipe and the supply is to be turned on a key, for example, 39 as shown in Figure 6, is used to open the ball valve. The key 39 has a body 40 with, at one end, a radial arm 41 for turning the key. From the other end projects a square spigot 42 to suit the socket 21, (Figures 1 and 2) of the ball valve. A curved wall 43 co-axial with the spigot 42 has an end face 44 which, when the spigot 42 is inserted in the socket 21 engages a face 45 (Figures 2) of a boss 46 through which the hole 18 opens. A stop 47 projects from the face 45 and enters a gap 48 (Figure 6) in the wall 44 when the spigot 42 is inserted in the socket 21.The stop 47 and gap 48 co-operate to limit the rotation of the ball valve to 900 so that it can be put accurately into the "On" and Off" positions as indicated in Figures 7 and 8 respectively. It will be understood that such a provision is desirable as the valve member 8 cannot be observed directly and accurate positioning is necessary, particularly in the "On" condition, to align the through passage 11 with the inlet opening 4 so as not to impede the flow of water.

Once the ball valve has been opened it is desirable that it be locked in that condition. A suitable locking device, which also prevents ingress of soil into the socket 21, is illustrated in Figure 9 and comprises a flexible plastics strap 50 long enough to encircle the valve body 3 at the level of the boss 46. One end 51 of the strap 50 is fitted with a square section peg 52 which projects on both sides of the strap 50. The other end 53 of the strap 50 has a square hole 54.

One end of the peg 52 is inserted into the socket 21, the strap bent round the valve body 3 and the outer end of the peg 52 engaged with the hole 54. To reduce the risk of the strap 50 being dislodged, it may be made wider as indicated by the broken line 55 in Figure 9 so as to fill the gap between the underside of the union nut 23 and the top of the water main 2.

Instead of a thick-walled spherical valve member 8 with a cylindrical through passage 11 as shown in Figures 1 and 2, the valve member may be made of sheet material with a hollow interior of spherical shape forming a hollow ball with walls of substantially uniform thickness. Diametrically opposed circular holes through the wall equal in diameter to the diameter of the inlet opening 4 enable the hollow interior of the ball to serve as a fluid passage though its changes of cross-section through the valve member do not provide as good a flow characteristic as the cylindrical passage 8. For turning the hollow ball an arcuate slot is provided through the wall, equivalent to the chordal groove of Figure 1, to receive the rib 16 of the drive member 17.

Instead of a separate device member 17 connected to the valve member by the engagement of the rib 16 in a groove or slot in the wall of the valve member 8, a drive member could be provided integrally with the spherical valve member, in the form of a trunnion or spigot in the end of which is a socket equivalent to the socket 21. To enable the valve member to be inserted into the valve chamber a groove may be provided in the wall of the outlet opening and leading into the valve chamber in line with the lateral hole in the wall of the valve chamber for the drive member. Alternatively or in addition, a lateral hole may be provided of larger diameter than the integral drive member. The valve member is inserted into the valve chamber, drive member first.

The drive member enters the lateral hole obliquely but can be brought coaxial with it when the valve member is seated. A bush is screwed or otherwise inserted in the lateral hole to serve as a bearing for the drive member. An O-ring seal, like the seal 20, may be provided between the integral drive member and the bush or the lateral hole whichever it is that affords the bearing.

The ball-valve illustrated in Figures 1 and 2 could also be replaced by a valve having a lenticular or shell-like valve member, for example shaped like the segment of a sphere, offset from its axis of rotation transverse to the flow path, as is the axis 15, so that the valve member rotates from a closed position over an opening, preferably the inlet opening, to an open position on one side of the flow path.

Figure 11 shows a modified form bf coupling means for a valve which can also be fitted by the previously described known single and double spindle machines. Instead of having the external thread 22 a collar 56 is provided which has an externally threaded spigot 57 to engage the thread 13 in the outlet opening 5 and an annular flange 58 which extends beyond the wall of the valve body 3 to be engaged by a union nut 59 assembled around the body after the fitting of the valve to the main pipe but before the collar 56 is fitted to the valve body. The union nut 59 is screwed onto a complementarily threaded portion of a suitable coupling on a pipe, bend or elbow or of the pipe, bend or elbow itself.

Figure 12 shows another modified form of coupling means for a valve which can be fitted by the known machines. After the valve has been fitted to the main water pipe, a collar 60 is connected to the valve outlet, for example, by capilliary soldering. A union nut 61 to engage the external thread on the collar 60 is provided on the pipe, bend or elbow represented at 62. Figure 12 also illustrates another feature equally applicable to any of the other forms of coupling means described. This is that the outlet opening 5 has a counterbore 63 to receive the end of the pipe bend or elbow 62 to align it with the outlet and so make it easier to engage the union nut 61 with the thread of the collar 60.

Figures 13 and 14 illustrate a further modification of the coupling means. At the upper end of the valve body 3 is provided an external annular collar 64 surrounding the outlet opening for engagement by an annular flange 65 of an upwardly facing union nut 66. A normal union nut would have to be fitted to the valve before the valve was mounted on the water main and is then likely to be too big to be fitted by the known machines particularly by the double spindle machines: To enable the union nut 65 to be fitted after the mounting of the valve on the main water pipe, the annular flange 66 is provided with two diametrically opposed notches 67 that open radially inwards into the central opening so that the annular collar 64 around the valve outlet can be inserted through the notches when the union nut 65 is angled relative to the valve.

A ball-valve can also be used to make a connection to a plastics or asbestos cement main water pipe.

Figures 15 and 16 illustrate such an arrangement in which a ball valve 1 as shown in Figure 1 and 2 is supported on a saddle 68 having a split clamp 69 around the main water pipe 2. Alternative means of securing the clamp 69 are shown in Figure 15. On the right-hand side of the figure a nut and bolt 70 are shown. On the left-hand side of Figure 15 and also in Figure 16 a clip 71, slidable longitudinally of the pipe 2, has an internal taper groove which co-operates with wedgeshaped lugs 72 on the separable parts of the split clamp 69 to form a dovetail joint. When the clip 71 is slid in the direction to engage its groove with the lugs 72 it tightens the clamp around the main water pipe.

The saddle has a screw-threaded taper socket 73 to receive the inlet spigot 6 of the valve 1 and around the socket 73 is a ring seal 82 between the saddle and the main water pipe 2. In making this type of connection the saddle 68 and valve 2 is mounted on the pipe and a special machine 74, provided with an internal screw thread 75 to engage the external screw thread 22 of the valve outlet, is mounted on top of the valve to drill a hole through the pipe 2 with the valve 1 open.

The machine 74 comprises a body 76 in the top of which is a journal bearing and gland 77 for a drill spindle 78 rotatable by an arm 79 connected to the spindle by a ratchet mechanism. A mushroom head 80 enables the user to apply axial pressure to the spindle during drilling. A tubular drill bit 81 is detachably mounted on the lower end of the spindle 78. After the hole has been drilled in the main water pipe the drill bit is retracted from its position in Figure 15 to that of Figure 16 above the valve member 8 which is then closed. The drilling machine 74 is then dismounted from the valve 1 to which the communication pipe can be connected in any of the ways previously described. In drilling a plastics or asbestos cement main water pipe the centre of the drill bit may become blocked by a plug of pipe material.As the drill bit is detachable it can be removed from the spindle after the machine has been taken off the valve and the plug driven out of the tubular bit by the use of a suitable punch.

Instead of the ferrule and saddle being separate components the body of the ferrule and the saddle could be made in one, for example as a unitary casting.

The main components of the valve 1 may be made of any suitable material including bronze, gunmetal and plastics.

Although a valve with a part spherical seating 10 is preferred, a connection according to the invention could also be made using a valve having a part cylindrical seating and a cylindrical valve member with a diametral flow passage, or a valve member of part cylindrical form mounted in a similar way to the lenticular valve member previously described. A cylindrical valve member may be rotated by a separate drive member similar to 17 in Figures 1 and 2 or by an integral spigot smaller in diameter than the valve member and similar to that previously described for a spigot integral with a spherical valve member.

In addition to its primary function as a connection for water supply purposes to premises, a connection according to the invention is also suitable for use as an air valve for bleeding air from high points in main water pipes. it is particularly suitable for such use when an air valve is needed at a road bridge and the covering by the road surface in which the main is laid is relatively thin. After uncovering the valve a hose may be connected to the valve outlet opening and the main water pipe flushed, the flush water being drained to waste through the hose.

A connection according to the invention can also be fitted to a main pipe at points at which pressure or flow readings are required, the straight through flow path of the ferrule enabling a manometer or pitot tube or other device to be inserted into the bore of the main pipe.

Claims (30)

1. A branch connection to a main pipe, which connection employs a valve comprising a valve body with coaxial inlet and outlet openings, the inlet opening extending through an externally screwthreaded spigot by which the valve is mounted on the main water pipe and the valve further comprising a valve member which is rotatably mounted in the valve body and has a sealing surface to close a flow path between said openings when the valve member is in a closed position, and the valve member being shaped so as to open said flow path without intruding therein when in an open position, thereby to allow the maximum unrestricted flow through said openings.

2. A branch connection to a main pipe as claimed in claim 1 wherein the sealing surface of the valve member lies on a sphere.

3. A branch connection to a main pipe as claimed in claim 2 wherein the valve has a ball-shaped valve member with a diametral bore that is aligned with said inlet and outlet openings in the open position.

4. A branch connection to a main pipe as claimed in any one of the preceding claims wherein the flow path through at least the inlet opening and the valve member is of substantially constant cross-sectional area.

5. A branch connection to a main pipe as claimed in any one of the preceding claims wherein the flow path through at least the inlet opening and the valve member is smooth walled.

6. A branch connection to a main pipe as claimed in any one of the preceding claims wherein the outlet opening of the valve is provided with coupling means for making a screw-threaded connection to a branch pipe.

7. A branch connection to a main pipe as claimed in claim 6 wherein the coupling means is co-axial with the outlet opening.

8. A branch connection to a main pipe as claimed in claim 6 or claim 7 where an elbow or bend is interposed between the coupling means and the branch pipe.

9. A branch connection to a main pipe as cliamed in any one of preceding claims 6 to 8 wherein the coupling means comprises a union nut on the valve.

10. A branch connection to a main pipe as claimed in any one of preceding claims 6 to 8 wherein the coupling means comprises an internal screw-thread in the valve body and surrounding the outlet opening.

11. A branch connection to a main pipe as claimed in any one of preceding claims 6to 8 wherein the coupling means comprises an external screw-thread on the valve body and surrounding the outlet opening.

12. A branch connection to a main pipe as claimed in any one of preceding claims 6 to 11 wherein the coupling means comprises a component separable from the valve during the fitting of the valve to a main water pipe.

13. A branch connection to a main pipe as claimed in claim 12 wherein the separable component is a flanged collar that engages an internal screw-thread in the valve outlet.

14. A branch connection to a main pipe as claimed in claim 12 wherein the separable compo nent is an externally screw-threaded collar around and connected to the outlet opening.

15. A branch connection to a main pipe as claimed in claim 14 wherein the externally screwthreaded collar is secured around the outlet opening by capillary soldering.

16. A branch connection to a main pipe as claimed in claim 12 wherein the valve body has an external annular flange around the outlet opening and the separable component is a union nut having in its annular shoulder two diametrically opposed notches that open radially inwards into the central opening, the annular flange being insertable through the notches when the nut is angled relative to the valve, thereby to assembly the nut on the valve.

17. A branch connection to a main pipe as claimed in claim 10 wherein the coupling means further comprises a screw-threaded bush received in the said internal screw thread surrounding the outlet opening and also adapted threadedly to engage a branch pipe.

18. A branch connection to a main pipe as claimed in any preceding claim wherein the branch connection further comprises a saddle by which the valve is supported on the main pipe.

19. A branch connection to a main pipe as claimed in claim 18 wherein the saddle comprises a girth strap by which the saddle is clamped to the main pipe.

20. A branch connection to a main pipe as claimed in claim 18 or claim 19 wherein the saddle is provided with an internally screw-threaded socket in which is received an external screw-thread around the inlet opening of the valve body.

21. A branch connection to a main pipe as claimed in any one of preceding claims 18 to 20 wherein the saddle is clamped to the main pipe, a sealing member being interposed between the saddle and the main pipe around an opening through the saddle aligned with the inlet opening of the valve.

22. A method of making a branch connection to a main pipe according to any preceding claim while the main pipe is under pressure, wherein the valve has a straight through flow path the method comprising the steps of mounting the valve on the main pipe, piercing a hole through the wall of the main pipe by drilling apparatus mounted on the valve, the hole being drilled through the valve in the open position, withdrawing the drill from the valve member and closing the valve member before the drilling apparatus is dismounted from the valve.

23. A branch connection made by the method of claim 22.

24. A branch connection to a main pipe substantially as described herein with reference to and as illustrated by Figures 1 and 2 of the accompanying drawings.

25. A branch connection to a main pipe substantially as described herein with reference to and as illustrated by Figures 1 and 2 as modified by Figure 11 of the accompanying drawings.

26. A branch connection to a main pipe substantially as described herein with reference to and as illustrated by Figures 1 and 2 as modified by Figure 12 of the accompanying drawings.

27. A branch connection to a main pipe substantially as described herein with reference to and as illustrated by Figures 1 and 2 as modified by Figure 13 of the accompanying drawings.

28. A branch connection to a main pipe substantially as described herein with reference to and as illustrated by Figures 1 and 2 as modified by Figures 13 and 14 of the accompanying drawings.

29. A branch connection to a main pipe substantially as described herein with reference to and as illustrated by Figures 15 and 16 of the accompanying drawings.

30. A branch connection to a main pipe made by the use of a machine substantially as described with reference to and as illustrated by Figures 15 and 16 of the accompanying drawings.