GB2330635A

GB2330635A - Procedure for tapping into fluid pipeline under pressure

Info

Publication number: GB2330635A
Application number: GB9722369A
Authority: GB
Inventors: Abbad Marcelo Hombravella; Vive Daniel Guillo
Original assignee: Individual
Current assignee: Individual
Priority date: 1997-10-24
Filing date: 1997-10-24
Publication date: 1999-04-28
Anticipated expiration: 2017-10-24
Also published as: GB9722369D0; GB2330635B

Abstract

The procedure utilises a collar (22) fixed onto the mains pipe with one half having a slot (22b) through which a bore blocking device may be inserted, the collar being so shaped inside as to fit around a shaped seal or seal combination (1) that makes a leakproof joint with the mains pipe and the blocking device; the collar retains a seal, e.g. an O-ring (2), for an inserted branch pipe (13), and a seal, e.g. an O-ring (3), the branch pipe. A clamp (4), a washer (5) separating the O-ring (3) and the clamp, a nut (6), and a seal, e.g. an O-ring (7), seal and retain the branch pipe (13) after a cutter has been inserted to provide an aperture in the mains pipe.

Description

PROCEDURE FOR TAPPING INTO FLUID PIPELINES UNDER PRESSURE DESCRIPTION OBJECT OF THE INVENTION The object of this Patent Application is a procedure for tapping into fluid pipelines under pressure which displays noteworthy advantages and innovations in comparison with current procedures used for the same or similar purposes.

More precisely, in this invention a procedure has been devised that allows the branch pipe to be connected directly to the mains pipe without the need to use intermediary accessories, so that both the branch accessory and the thread between the collar and this accessory are eliminated, resulting in a saving in material, easier assembly and a more reliable joint without the thread between the collar and the accessory, since this thread must be leaktight once installation is complete.

BACKGROUND TO THE INVENTION With regard to the current state of technical knowledge, a known system for tapping into mains pipes under pressure consists of a collar fitted with the sealing elements needed for tapping under pressure, the end of which has a female thread for screwing in an elbow or other type of accessory, to which the branch pipe is connected.

Another known system uses a collar of the type described in the previous paragraph, but one which ends in a tube to which an accessory for connecting to the branch must be fitted.

Yet another known system consists of a collar without any sealing elements, to which is fitted a device allowing the connection to be made under pressure, to which in turn is fitted an accessory for making the connection to the branch pipe.

DESCRIPTION OF THE INVENTION The procedure for tapping into fluid pipelines under pressure, the object of this invention, consists of a collar fixed onto the mains pipe by some traditional means.

The upper half of this collar has a slot through which a spatula may be inserted, the collar being suitably shaped inside to house a multiple seal that makes a leakproof joint with the mains pipe and the spatula, together with an O-ring seal which kes a leakproof joint with the branch pipe.

In addition, placed on top of the collar there is an O-ring seal which will make a leakproof joint with the branch pipe; a clamp which will hold the branch pipe and prevent it from coming out once assembled, there being a gripping system on the inside of the clamp and a conical surface on the outside, the whole clamp being split axially so that it can easily deform and adjust to the pipe; and a washer separating the O-ring and the clamp.

Fitted outside the collar there is a nut which screws onto the outer surface of the collar, the nut having inside it a conical surface that coincides with that of the clamp and an Oring seal to give an extra guarantee against leakage once the assembly is installed; and a further O-ring seal for the same purpose.

The installation process consists first of fixing the collar onto the pipe to be tapped. Then, the O-ring, washer, clamp and nut are removed from the collar, and by means of a threaded adapter a suitable pipe drill is installed on top of the collar. This drill must have the sealing elements needed to prevent leakage once the pipe is pierced.

When the pipe has been drilled and the drill bit is withdrawn, the spatula is inserted by sliding it over the multiple seal, thus allowing the drill to be removed without leakage. The parts previously removed from the collar, i.e. the O-ring, washer, clamp and nut, are replaced, the nut being screwed down until it touches the spatula but without pressing on it, and the branch pipe is inserted until it butts against either a shoulder inside the collar or the spatula itself.

Once the other end of the branch pipe has been closed by means of a valve or other type of closure, the spatula is removed, so that the pressure entering the branch pipe pushes the pipe outwards. But it is held in by the clamp, which closes onto it because of its conical surfaces, with the detail that the assembly remains leakproof thanks to the O-ring seal located inside the collar.

Finally the nut is screwed right down, drawing the pipe inwards as far as it will go, and the clamp closes even more, gripping the pipe tighter until installation is complete.

This arrangement means that later, if necessary, this collar can be used as a shut-off valve by unscrewing the nut just enough and inserting the spatula.

A set of plans accompanies this application to complement the description that follows and to aid in understanding its characteristics. These figures, which are non-restrictive and for illustration only, show the major details of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS Figures 1 to 7 show views in vertical section of the successive stages in the process of installing the invention.

Figures 8 to 12 show views in vertical section of various ways in which certain elements of the invention may be implemented.

DESCRIPTION OF A PREFERENTIAL IMPLEMENTATION With reference to the above-mentioned figures and in accordance with the numbering adopted, in this implementation a collar 22 is shown, which is fixed onto the mains pipe by some traditional means.

The upper half of this collar has a slot 22b through which a spatula 12 may be inserted, the collar being suitably shaped inside to house: - A multiple seal 1 making a leakproof joint with the mains pipe and the spatula 12.

- An O-ring seal 2 making a leakproof joint with the branch pipe 13.

Placed outside the collar there is: - An O-ring seal 3 to make a leakproof joint with the branch pipe 13; - A clamp 4 to hold the branch pipe and prevent it from coming out once assembled. The clamp has a gripping system 4a on the inside and a conical surface 4b on the outside. The clamp is split axially so that it can easily deform and adjust to the pipe.

- A washer 5 separating the O-ring and the clamp.

- A nut 6 screwed onto the outside of the collar; inside the nut is a conical surface 6a that coincides with that of the clamp.

- An O-ring seal 7 to give an extra guarantee against leakage once the assembly is installed. Inside the nut there is a further O-ring seal 8 for the same purpose.

The installation process is as follows: The collar is firmly fixed onto the pipe to be tapped (figure 1).

The O-ring 3, washer 5, clamp 4 and nut 6 are removed from the collar, and by means of a threaded adapter 9 a suitable pipe drill 10 is installed on top of the collar. This drill must have the sealing elements needed to prevent leakage once the pipe is pierced (figure 2).

When the pipe has been drilled and the drill bit 11 is withdrawn, the spatula 12 is inserted by sliding it over the multiple seal 1, thus allowing the drill 10 to be removed without leakage (figures 3 and 4).

The parts previously removed from the collar (O-ring 3, washer 5, clamp 4 and nut 6) are then replaced, the nut 6 being screwed down until it touches the spatula 12 but without pressing on it, and the branch pipe 13 is inserted until it butts against either a shoulder 14 inside the collar 22 or the spatula 12 itself (figure 5).

Once the other end of the branch pipe 13 has been closed by means of a valve or other type of closure, the spatula 12 is removed, and the pressure entering the branch pipe 13 pushes the pipe outwards. But it is held in by the clamp 4, which closes onto it because of its conical surfaces 4b, 6a, so that the assembly remains leakproof thanks to the inner O-ring seal 2 (figure 6).

The nut is screwed right down, drawing the pipe inwards as far as it will go, and the clamp closes even more, gripping the pipe tighter until installation is complete (figure 7).

Later, if necessary, this collar can be used as a shut-off salve by unscrewing the nut just enough and inserting the spatula.

In a preferential implementation of the invention, the collar is composed of two half-collars fixed together by screws or other fasteners. The upper half-collar 24 is fitted with the tapping elements described above (figure 8).

In another form of implementation, the collar is made of two totally different parts: an upper seating 15 that bears the tapping system, and a lower deformable clamp 16 which adjusts to the girth of the pipe and fixes the seating to the pipe. The seating and clamp may be joined together by screws 17 or other fasteners (figure 9).

Another form of implementation is envisaged in which the upper part of the collar, in either the half-collar version or the seating version, is made up of two parts: one is the halfcollar or seating itself 18, housing the multiple seal, and the other is a body 19 with all the tapping elements described above. Between the body and the multiple seal some system is envisaged to prevent turning, whether through friction, a twistproof lug, or some other system (figure 10). In addition, one of the parts that make up the collar may be coated with some insulating material in order to prevent galvanic corrosion.

In one variant implementation, the multiple seal is replaced with two independent seals: one 20 to make a leakproof seal with the mains pipe, and the other 21 to make a leakproof seal with the spatula and slot (figure 11).

In another variant implementation, the nut is ribbed 14 to enable it to be tightened by hand or with a hook spanner (figure 8).

In yet another variant the open clamp is replaced with a closed clamp 23 or ring, which can be factory fitted on a branch pipe of the required length (figure 12).

Furthermore, the outer shape of the collar allows a version of the adapter 9 to be attached which has a groove 9a inside, with an O-ring 9b that slides over the outer surface of the collar 22a (figures 2 and 3).

This allows the adapter to be raised to uncover the slot 22b without leakage. The advantage of this system is that when the pipe is being drilled the adapter reinforces the upper part of the collar, which otherwise would be weakened by the slot.

Claims

CLAIMS 1.-PROCEDURE FOR TAPPING INTO FLUID PIPELINES UNDEF PRESSURE, by means of which the branch pipe can be connectec directly to the mains pipe without the need to use intermediarb accessories, characterized because it comprises a collar (22) fixed onto the mains pipe by some traditional means, with the peculiarity that the upper half of this collar has a slot (22b) through which a spatula (12) may be inserted, the collar beinc so shaped inside as to fit around a multiple seal (1) that makes a leakproof joint with the mains pipe and the spatula (12), together with a seal, preferably an O-ring (2), which makes c leakproof joint with the branch pipe (13), there being on the outside of the above-mentioned collar a seal, preferably an Oring (3), that can make a leakproof joint with the branch pipe, a clamp (4), a washer (5) separating the O-ring and the clamp, ; nut (6), and an O-ring seal (7) to give an extra guarantee against leakage once the assembly is installed; the abovementioned clamp (4) holds the branch pipe to keep it in place and has a gripping system (4a) on the inside and a conical surface (4b) on the outside, the clamp being split axially enabling it to deform and adjust to the pipe; the nut (6) screwy onto the outside of the collar and has inside it a conical surface (6a) , coinciding with that of the clamp, and a seal, preferably an O-ring (8), to give an extra guarantee against leakage when the assembly is installed.
2.- PROCEDURE FOR TAPPING INTO FLUID PIPELINES UNDEF PRESSURE, according to claim 1, characterized because in e preferential installation process the collar is firmly fixec onto the pipe to be tapped, the O-ring (3), washer (5), clam (4) and nut (6) are removed from the collar, and by means of c threaded adapter (9) a suitable pipe drill (10) is installed or top of the collar with the sealing elements needed to drill thc pipe, and when the pipe has been drilled and the drill bit (11) is withdrawn, the spatula (12) is inserted by sliding it ovei the multiple seal (1), thus allowing the drill (10) to be removed without leakage, after which the parts previously removed from the collar (3, 5, 4 and 6) are replaced, the nut ing screwed down until it touches the spatula (12) but without pressing on it, the branch pipe (13) then being inserted until it butts against either a shoulder (14) inside the collar or the spatula (12) itself, the other end of the branch pipe then being closed by means of a valve or other type of closure, so that when the spatula (12) is removed, the pressure entering the branch pipe (13) pushes the pipe outwards, but it is held in by the clamp (4), which closes onto it because of its conical surfaces (4b), (6a), the assembly remaining leakproof thanks to the inner O-ring seal, the nut then being screwed right down, drawing the pipe inwards as far as it will go, while the clamp closes even more, gripping the pipe tighter until installation is complete.
3.- PROCEDURE FOR TAPPING INTO FLUID PIPELINES UNDER PRESSURE, according to claims 1 and 2, characterized because in a preferential form of implementation the collar is composed of two half-collars held together by screws or other fasteners, the upper half-collar (24) being fitted with the tapping elements described above.
4.- PROCEDURE FOR TAPPING INTO FLUID PIPELINES UNDER PRESSURE, according to claims 1 to 3, characterized because in a preferential form of implementation the collar is composed of two different parts: an upper seating (15) with the tapping system, and a lower deformable clamp (16) which adjusts to the girth of the pipe and fixes the seating to the pipe, the seating and clamp being joined together by screws (17) or other fasteners.
5.- PROCEDURE FOR TAPPING INTO FLUID PIPELINES UNDER PRESSURE, according to claims 1 to 4, characterized because in a preferential form of implementation the upper part of the collar, in either the half-collar version or the seating version, is made up of two parts corresponding to a half-collar (18) housing the multiple seal, and a body (19) with all the tapping elements, some system being envisaged between the body and the multiple seal to prevent turning, for instance through friction or a twist-proof lug, one of the parts that make up the collar possibly being coated with some insulating material that prevents galvanic corrosion.
6.- PROCEDURE FOR TAPPING INTO FLUID PIPELINES UNDER PRESSURE, according to claims 1 to 5, characterized because the outer shape of the collar allows a version of the adapter (9) to be attached which has a groove (9a) inside, with an O-ring (9b) that slides over the outer surface of the collar (22a), allowing the adapter (9) to be raised to uncover the slot (22b) without risk of leakage.
7.- PROCEDURE FOR TAPPING INTO FLUID PIPELINES UNDER PRESSURE, according to claims 1 to 6, characterized because in one variant implementation of the invention the multiple seal (1) is replaced with two independent seals: one (20) making a leakproof seal with the mains pipe, and the other (21) making a leakproof seal with the spatula and slot.
8.- PROCEDURE FOR TAPPING INTO FLUID PIPELINES UNDER PRESSURE, according to claims 1 to 7, characterized because in a variant implementation of the invention the nut (6) is ribbed (14) to enable it to be tightened by hand or with a hook spanner.
9.- PROCEDURE FOR TAPPING INTO FLUID PIPELINES UNDER PRESSURE, according to claims 1 to 8, characterized because in a variant implementation of the invention the open clamp (4) is replaced with a closed clamp (23) or ring, which may be fitted in advance on a branch pipe of the required length.

As is described and claimed in this application, which consists of 27 numbered pages.

In Madrid, on 12 February 1996