Device and process for perforating a duct fitted with a connector seat

A perforating device capable of perforating a process for perforating a fluid duct having a connector seat with a tapped barrel. The device generally includes a hollow cylindrical body, a cutting apparatus, a fluid passage and a valve. The cylindrical body has an internal volume, a longitudinal axis, a first open end, a second end opposite the first, and a threaded external surface. The cylindrical body can be threadingly received or retracted within the barrel such that the cylindrical body moves along the barrel toward or away from the fluid duct. The cutting apparatus is operably coupled to an end of the cylindrical body and is adapted to cut the duct by screwing the body into the barrel. The valve seals the internal volume of the cylindrical body in response to a differential pressure between the interior of the duct and the ambient atmosphere to prevent leakage from the duct.

RELATED APPLICATIONS

This application claims priority to PCT Application No. PCT/FR2006/002587 filed Nov. 24, 2006, French Application No. 0607361, filed Aug. 17, 2006, and French Application No. 0512184, filed Nov. 30, 2005, the disclosures of which are hereby incorporated by reference in their entireties.

TECHNICAL FIELD

The invention relates, in general, to the techniques related to the design and operation of fluid systems, especially gas.

More precisely, the invention relates, in a first aspect, to a perforating device capable of perforating a fluid duct having a connector seat with a tapped barrel.

BACKGROUND OF THE INVENTION

The use and laying of ducts for the distribution of gas implies the use of specific accessories, such as, for example, connector seats, also referred to as “connector sockets”, which permit a duct of a smaller diameter to be connected to a main duct.

These seats or “connector sockets” allow two operations to be carried out: firstly, the impervious welding of the smaller diameter duct onto the main duct, and secondly, the perforation of this main duct to supply the smaller diameter duct with gas.

Today, gas ducts are generally made of polyethylene, and may therefore be thermal welded, but must be fitted with automatically actuated valves that are sensitive to a differential pressure to avoid any untimely gas leaks in the event of an accidental rupture of the smaller diameter duct, downstream of the connector seat.

A device of the above-mentioned type is described in U.S. Pat. No. 3,692,044.

This known device, which has complex geometry, is large and is quite expensive, and furthermore has the disadvantage of not offering both vertical perforation and a vertical outlet barrel.

SUMMARY OF THE INVENTION

The present invention provides a perforating device that does not have at least one of the above described limits and which further enables a loaded duct to be fitted with an automatically actuated valve.

To this end, the device of the invention, generally includes a hollow cylindrical body, a cutting appartus, a fluid passage and a valve. The cylindrical body has a free internal volume, an axis, a first open end via which this body may be driven in rotation around its axis, a second end opposite the first, and a threaded external face such that the cylindraical body may be threadingly received or removed with respect to this barrel The cutting apparatus is held, at least in a first configuration of the device, by the second end of the cylindrical body and is suited for cutting the duct at a level of the barrel of the seat by screwing in the body. The fluid passage is defined, at least in a second configuration of the device, between the cutting appartus and the first end of the cylindrical body that communicates with the inside of the duct after the latter has been cut. The valve is sensitive to a differential pressure and capable of selectively sealing the internal volume of the cylindrical body so that there are no leaks.

In a first embodiment of the device, the first and second configurations are identical, wherein the cutting apparatus is formed on the front edge of the second end of the cylindrical body, the fluid passage comprises at least one lateral orifice which passes through the cylindrical body and is positioned between the first and second ends of this body, and the valve is fitted inside the free volume of the cylindrical body between the fluid passage and the first end of the body.

The lateral orifice may then be fitted closer to the second end of the cylindrical body than to the first end.

In a second embodiment of the invention, the device can comprise a reversible connection assembly and elastic solicitation assembly. The reversible connection assembly is operably coupled to the cutting apparatus at least in rotation to the second end of the cylindrical body in the first configuration of the device and frees the cutting apparatus, at least in translation, from the second end of the cylindrical body in the second configuration of the device. The fluid passage is formed in the second configuration of the device, between the second end of the cylindrical body and the cutting apparatus, of which one forms a seal and the other a seat for the valve. The elastic solicitation assembly is part of the valve and manipulates the cutting apparatus in a direction which moves it away from the second end of the cylindrical body.

In this case, the reversible connection assembly comprises at least one pair of complementary contoured parts, wherein each pair comprises first and second contoured parts of which one is part of the cylindrical body and the other is part of the cutting apparatus.

For example, the complementary contoured parts have convex and concave frontal contours which interpenetrate one another, or have a bayonet connection solicited in the locking direction by screwing the cylindrical body into the barrel.

The device of the invention can further comprise at least one annular seal carried by the cylindrical body and capable of imperviously sealing the barrel of the seat.

The tapped barrel can include, on the side opposite the duct, an internal annular lip which acts as a stop for the first end of the cylindrical body. The annular seal is interposed between this internal lip and the first end of the cylindrical body and is axially compressed for an unscrewed position of the cylindrical body inside the threaded barrel.

Furthermore, the threaded barrel can include, on the side of the duct, a base with a diameter that is greater than the diameter of the cutting apparatus, wherein the latter comprises a hole saw, for example.

The invention also is directed to a process for perforating a loaded fluid duct, including screwing a device as previously defined into the tapped barrel of the connector seat fitted to this duct until the cutting apparatus cuts the duct, and of unscrewing this device from the barrel until the cutting apparatus is cleared and is distant from the cut-out made in the duct.

DETAILED DESCRIPTION OF THE DRAWINGS

As previously mentioned, and as depicted inFIGS. 6,8, and10, the invention relates to a perforating device capable of perforating a fluid duct1, for example made of polyethylene, having a connector seat2which itself has a tapped barrel21.

According to the invention, this device comprises a hollow cylindrical body3with an axis X, a cutting apparatus4, such as, for example a hole saw, a fluid passage5, and a valve6.

As depicted inFIGS. 4 and 5, a holder34, fitted inside a free internal volume30of cylindrical body3and for example in the form of a cross, supports the sliding action of an axis64of valve6.

Cylindrical body3is open at at least one of these ends, wherein end31is fitted with suitable drive contours which permit cylindrical body3to be driven in rotation around its axis X.

Other end32of cylindrical body3is designed to be inserted first into tapped barrel21of connector seat2, except in the embodiment ofFIG. 10, in which cylindrical body3is inserted into tapped barrel21by end31before connector seat2is fitted onto duct1.

Furthermore, the cylindrical body3has a screw thread on external face33, so that it may be threadingly received and threadingly removed as required with respect to barrel21of seat2by rotating end31.

Cutting apparatus4, is adapted to cut duct1in line with barrel21by screwing in body3, and is at least temporarily carried by end32of body3.

Fluid passage5, which communicates with the inside of duct1after the latter has been cut, is temporarily defined between cutting apparatus4and end31of cylindrical body3.

Finally, valve6is sensitive to a differential pressure and suited to imperviously seal, if required, internal volume30of cylindrical body3.

Valve6typically comprises a seal cover61, a seal cover seat62, a return spring63and an axis64, which is mounted so that it slides in carrier34.

In a first embodiment of the invention, illustrated inFIGS. 1A,1B,4and6to7D, cutting apparatus4is, for example, directly formed by the front edge of end32of cylindrical body3.

Fluid passage5defines one or several lateral orifices50passing through cylindrical body3and positioned between ends31and32of this body3, typically closer to end32of the latter than to drive end31.

In a second embodiment of the invention, illustrated inFIGS. 2A,2B,3A to3C,5and8to9D, the device can have at least two different configurations, for example, as illustrated inFIGS. 8 and 9D, and further comprises reversible connection assembly7and elastic solicitation assembly63.

Reversible connection assembly7operably couples cutting apparatus4, at least in rotation, to the end of cylindrical body3in the first configuration of the device illustrated inFIGS. 8,9A and9B, and frees cutting apparatus4, at least in translation, in the second configuration of the device illustrated inFIGS. 2A,2B,9C and9D.

In the second configuration of the device, fluid passage5is thus formed between end32of cylindrical body3and cutting apparatus4, wherein one of either end32or cutting apparatus4forms a seal cover61for valve6, and the other forms a seat62for valve6.

Even though it is part of valve6, elastic solicitation assembly63, which can comprise, for example, a helicoidal spring, includes the function of manipulating cutting apparatus4in a direction which moves them away from end32of cylindrical body3and therefore of defining fluid passage5, at least in the absence of any differential pressure likely to close valve6.

As shown in particular byFIGS. 3A to 3C, reversible connection assembly7typically can include one or several pairs of complementary contoured parts71and72.

One of the contoured parts, for example71, is part of cylindrical body3, while the other is part of cutting apparatus4.

Contoured part71may define a tab and contoured part72define a square groove, as illustrated inFIGS. 3A and 3B, wherein reversible connection assembly7thus form one or more bayonet connections.

In this case, this connection can be manipulated in the locking direction by screwing cylindrical body3into barrel21, and in the release direction by unscrewing cylindrical body3from barrel21.

As depicted inFIGS. 2A,2B, and3C, complementary contoured parts71and72may also comprise convex and concave frontal contours which inter-penetrate one another.

One or more annular seals, such as330and331, are provided, for example on cylindrical body3to seal barrel21of the seat imperviously.

In AN embodiment illustrated inFIG. 10, tapped barrel21includes, on the side opposite duct1, an internal annular lip210which acts as a stop for first end31of cylindrical body3, which permits annular seal331to be interposed between this internal lip210and first end31of cylindrical body3.

Annular seal331can, for example, be housed in a peripheral groove on the frontal profile of cylindrical body3, but may also be housed in an internal groove on lip210of barrel21.

Annular seal331may be effectively axially compressed by threadingly removing cylindrical body3from inside threaded barrel21, and does not run the risk of being damaged by rubbing against the screw thread of barrel21and only suffers a moderate shear stress to reach its impervious position.

Furthermore, referring toFIGS. 6 to 9D), tapped barrel21presents, on the side of duct1, a base20with a diameter that is greater than the diameter of cutting apparatus4, when cutting apparatus4comprises a hole saw.

The use of the device in accordance with a first embodiment of the invention is illustrated inFIGS. 6 to 7D.

This device is firstly introduced into tapped barrel21.

Regardless of the embodiment, the device may be introduced before seat2is mounted onto duct1, but may also be carried out afterwards, except for the embodiment depicted inFIG. 10.

Once the screw thread of external face33of body3is engaged into the screw thread of barrel1and seat2is in place on duct1, a rotational movement is applied to body3, referring toFIG. 6, to screw the device into barrel21using an appropriate tool introduced into end31of body3and operating together with contoured parts36.

When the device comes into contact with duct1, as illustrated inFIG. 7A, cutting apparatus4, by the application of the rotational movement, cuts the wall of this duct1.

The cut out, such as, for example, a disc, of this wall is conserved inside cutting apparatus4, as depicted inFIG. 7B.

The device is then unscrewed from barrel21by reversing the direction of rotation, as depicted inFIG. 7C.

Unscrewing it permits the device to be freed from hole10cut into the wall, as depicted inFIG. 7D.

The pressurized fluid from the perforated duct then enters orifices50of passage5and, in the absence of counter-pressure applied to open end31of body3, causes the closure of valve6, thus sealing the assembly with respect to the fluid circulating in duct1.

Once barrel21is connected to an impervious installation, applying a counter-pressure permits valve6to be opened and thus to connect this installation to duct1.

The use of the device in accordance with a second embodiment of the invention is illustrated inFIGS. 8 to 9D.

FIG. 8shows the hypothesis that reversible connection assembly7comprises a bayonet connection.

The device is first introduced into tapped barrel21in the same way as the device according to the first embodiment.

Using a suitable tool introduced into end31of body3and operating together with contoured parts36, a rotational movement is applied to body3, as depicted inFIG. 8,FIG. 8) to screw the device into barrel21, wherein the bayonet connection is then manipulated in the locking direction.

When the device comes into contact with duct1, as depicted inFIG.9A, cutting apparatus4, by the application of the rotational movement, cuts the wall of duct1.

The cut out, such as a disc, of this wall is conserved inside cutting apparatus4, as depicted inFIG. 9B.

The device is then unscrewed from barrel21by reversing the direction of rotation, as depicted inFIG. 9C. The bayonet connection is then manipulated in the release direction, wherein cutting apparatus4is moved away from end32of body3under the action of spring63.

Unscrewing the device permits the device to be freed from hole10cut into the wall, illustrated inFIG. 9D.

The pressurized fluid from the perforated duct then enters passage5created between cutting apparatus4and end32of body3.

In the absence of counter-pressure applied to open end31of body3, the pressurized fluid causes the closure of valve6, thus sealing the assembly with respect to the fluid circulating in duct1.

Once barrel21is connected to an impervious installation, applying a counter-pressure permits valve6to be opened and thus to connect this installation to duct1.