PIPE REPAIR AND THE METHODS FOR OPERATIONAL FIXING AND DEFINITIVE WELDING THEREOF

Abstract

The present invention relates to the repair of pipes, comprising a two-part ring fixed initially by a compression unit which allows the execution of longitudinal welding in order definitively to fix the two-part ring, via apertures, before the compression unit is removed. The two-part ring will be completely welded to the pipe, especially in regions close to connections, but it is necessary for the two-part ring to be fixed initially by the compression unit for the purpose of shaping and definitive geometry of the ring relative to the pipe, normalization of fluid conveyance and in order that it is possible for welding to be planned for the opportune moment.

Claims

1. Pipe repair system by compression of split sleeves with sealant against the outer surface of the pipe, comprising a split ring (1) with total thickness corresponding to the sum of the thickness of the channel (2) of accommodation of the sealant (8), plus the thickness of the back (3), which is equivalent to the back plate, and plus the extension (19) with the thickness for welding (4) and total width (5) of the split ring (1), which is the sum of the width of the channel (6) to accommodating the sealant (8) and the two lateral widths (7), being the portions of the split ring initially attached to the pipe by the compression unit (9), made by two hollow rectangular pieces, forming apertures (10), built to allow the welding areas, which correspond to the fitting region (15) of the parts of the split ring (1), can be accessible to the welding, interconnected by chains (12), the compression being made by a connector which will approximate the chains (12) of the compression unit (9) with a single screw (11) with the aid of guide pins (20) so that the compressive force exerted by the screw (11) is only in the direction of the tightening, preventing the screw (11) from damaging.

2. Pipe repair system according to claim 1, wherein the extension (19) with thickness for welding (4) can be either in the two ends of a single part of the split ring (1) or at one of the ends of the two parts of the split ring (1).

3. Pipe repair system according to claims 1 and 2, wherein the thickness required for welding (4), the lateral widths (7) and the thickness of the backing strip (3), which equals the back plate, should be greater than or equal to the thickness of the pipe or tube to be repaired.

4. Pipe repair system according to claim 1 wherein the minimum total width (5) of the split ring (1) required to form the channel (6) to accommodating the sealant (8) is 20 millimeters.

5. Method of fixing the pipe repair system in the pipelines while in operation wherein the fitting region (15) of the parts of the split ring (1) is in condition to be filled with solder, via apertures (10), before the compression unit (9) is removed.

6. Method of fixing the pipe repair system in the pipelines while in operation according to claim 5 wherein the compression of the split ring (1) either on the pipe or on the connection will cease leakage by contact of the sealant (8) with the surface of the pipe or connection and, the split ring (1) assembly and compression unit (9) will act as reinforcement of the mechanical resistance of the pipe in the site of damage, preventing the cracking, crevice corrosion and embrittlement of the pipe.

7. Methods of fixing the pipe repair system in the pipelines while in operation, according to claim 6 wherein the sealant (8) is chosen from composites, polymers, gaskets or graphite gasket.

8. Methods of fixing the pipe repair system in the pipelines while in operation, according to claim 5 wherein the welding is performed prior to the removal of the compression unit (9), performing the longitudinal welding (16) via apertures (10) and carrying out the circumferential welding (17) in the region of the hollow rectangular parts (18).

9. Methods of fixing the pipe repair system in the pipelines while in operation, according to claim 8, wherein the circumferential welding (17) is finalized in the region of the hollow rectangular part (18).

10. Methods of fixing the pipe repair system in the pipelines while in operation, according to claims 8 and 9, characterized by using welding with heat input control.

Description

DESCRIPTION OF DRAWINGS

[0018] The disclosed invention will be described with reference to the accompanying drawings, which show important sample embodiments of the invention and which are incorporated in the specification. A more complete understanding of the invention may be had by reference to the detailed description when taken in conjunction with the accompanying drawings, wherein:

[0019] FIG. 1 is a transverse cross section of the fitting region (15) of the parts of the split ring (1) in the pipe repair system.

[0020] FIG. 2 is an enlarged perspective view of one of split ring (1)′ end.

[0021] FIG. 3 is a perspective view of the compression unit (9).

[0022] FIG. 4 is a perspective view of compressed split rings (14) or welded (13) in a pipe and connections.

[0023] FIG. 5 is an enlarged perspective view of the split ring's welding or fitting region (15) and its details.

[0024] FIG. 6 is an enlarged perspective view of welding longitudinal (16) and circumferential (17) of the split ring (1).

DETAILED DESCRIPTION

[0025] One or more exemplary embodiments of the present invention will be described below. In an effort to provide a concise description of these embodiments, not all features of an actual implementation are described in the specification. The present invention discloses a system for repairment of pipes as well as methods of fixing the pipes using such system while in operation and a later definitive welding of the repair in an opportune moment. The invention comprises a split ring (1) with total thickness corresponding to the sum of the thickness of the channel (2) of accommodation of the sealant (8), plus the thickness of the backing strip (3), which is equivalent to the back plate, and plus the thickness for the welding (4). The thickness for the welding (4) must be greater than or equal to the thickness of the pipe to be repaired, as shown in the FIG. 1.

[0026] FIG. 1 also shows the two possible embodiments of machining or casting the ends of the split ring parts (1). For these embodiments, the extension (19) with the thickness for the welding (4) can be either in the two ends of a single part as in the left side ring, or at one of the ends of the two parts as in the right side ring.

[0027] The total width (5) of the split ring (1) corresponds to the sum of the width of the channel (6) and the two lateral widths (7) for heat dissipation during the welding. The minimum total width is 20 millimeters, allowing the generation of the channel for the sealant (8) inside the split ring (1), as shown in FIG. 2.

[0028] The thickness of the back (3), the width of the channel and the lateral widths (7) for heat dissipation while welding are calculated as a function of the sealant (8) chosen, and the thermal input during the welding. The expected thickness of the back (3) is at the minimum the pipe thickness and the lateral widths (7). In this way, the heat dissipation while welding is at a minimum equal to the thickness of the pipe.

[0029] The initial correction of the repair is made without welding, i.e., using a compression unit (9) that will attach the parts of the split ring to the pipe surface or connection, allowing a later weld to be carried out in the opportune moment.

[0030] FIG. 3 presents the compression unit (9) with two hollow rectangular pieces, forming apertures (10). The apertures allow accessibility of the welding area of the split ring (1)'s parts to the welding with the unit, exerting the compression on the split ring (1) to keep it fixed to the pipe or connection. FIG. 3 shows also that the compression is done by a connector as a single screw (11) that will get the chains (12) near to the compression unit (9), with the aid of guide pins (20) so that the compressive force exerted by the screw (11) is only in the direction of the tightening, preventing the screw (11) from damages.

[0031] The compression of the split ring (1) on the pipe or connection will stop the leakage by the contact of the sealant (8) with the surface of the pipe or connection. The split ring (1) assembly and compression unit (9) will act as reinforcement of the mechanical resistance of the pipe in the site of damage, preventing crack propagation or crevice corrosion and pipe rupture.

[0032] The sealant (8) must be chosen for its capability to adapt to the pipe surface's irregularities. The sealant (8) is selected among composites, polymers and gaskets, as, for example, but not limited to, Graphite Gasket.

[0033] FIG. 4 illustrates the situation when the split ring can receive a definite welding (13). In this scenario, the split ring becomes definite part of pipeline or is provisionally fixed (14), using the compression unit (9).

[0034] FIG. 5 shows in detail the fitting region (15) of the parts of the split ring (1) in condition to be filled with solder, through the apertures (10), before the compression unit (9) is removed.

[0035] Once joined to the parts of the split ring (1), carrying out the longitudinal welding (16), the welding can be made along the circumference of the pipe or connection. The circumferential welding (17) can start with the compression unit (9), which must be removed only for the completion of the circumferential welding (17) in the region of the hollow rectangular parts (18), as shown in FIG. 5.

[0036] Welding with heat input control prevents high temperatures in the welding process. The uncontrolled rise of temperatures during the welding can damage the seal and the pipe, already weakened by flaws.

[0037] The present invention has been described by its features understood as more expressive. However, certain variations and modifications will become apparent to one skilled in the art after the present description. Such variations and modifications are not in any way limiting and are included in the scope of the present invention.