THREADED INSERT FOR CONNECTIONS OF TUBES AND ACCESSORIES FOR LIQUID AND GASEOUS FLUIDS IN GENERAL

Abstract

The present invention relates to a threaded insert for the connection of tubes and accessories, such as fittings for liquid and gaseous fluids in general, directed to the tube male/female connections of the type that are connected together from one of its ends by thermo fusion, cold welding, with rubber ring, among other possible forms of connection, that prevent the leakage through the male/female connection of the pieces. That includes a tubular metallic body, which includes a first male segment tightly coupled to the end of a pipe or the fitting, and a second male segment including an outer coating of elastomeric material which defines a thread sealant between the parts to be connected. The first male segment includes a cross-section larger than the diameter of the second male segment, thus forming a step between both segments. Preferably, the elastomeric material is PTFE (polytetrafluoroethylene), even though in practice can also use other materials that perform the sealing function efficiently.

Claims

1. A threaded insert for connecting tubes and fittings for liquid and gaseous fluids comprising: a tubular body including: a first male segment adapted to be tightly coupled to an end of a pipe or a fitting; a second male segment having a coating made of an elastomeric material including threads.

2. The insert according to claim 1, wherein the elastomeric material is polytetrafluoroethylene.

3. The insert according to claim 1, wherein the elastomeric material is thermoplastic material.

4. The insert according to claim 2, wherein the elastomeric material coating is arranged in the form bands wounded along the second male segment of the tubular body.

5. The insert according to claim 1, wherein the elastomeric material is applied to the second male segment as a paint bath.

6. The insert according to claim 1, wherein the first male segment and the second segment of the insert are shaped by a single metal piece.

7. The insert according to claim 6, wherein the metal piece is made of brass, copper, iron, stainless steel, or zinc.

8. The insert according to claim 1, wherein the first male segment has a diameter larger than a diameter of the second segment forming a step.

9. The insert according to claim 1, wherein the elastomeric material extends over the step.

Description

BRIEF DESCRIPTION OF DRAWINGS

[0009] For greater clarity and understanding of the object of the present invention, it has illustrated in several figures that represent it in one of the preferred ways of preparation, all for example, where:

[0010] FIG. 1 is a perspective view of the insert according to an embodiment of the present invention;

[0011] FIGS. 2A and 2B are cross sectional views of the insert of FIG. 1 showing two possible forms of implementation; and

[0012] FIG. 3 is a perspective view of the insert of FIG. 1 showing the insert having an elbow shape.

DETAILED DESCRIPTION OF THE INVENTION

[0013] FIGS. 1 and 2 show the insert 1 of the present invention having a tubular body that includes a first male segment 2 from which tightly fits to the end of a tube (pipe) or a fitting, and a second male segment 3 coated by a layer of an elastomeric polymer 4 which includes an external thread 5. This polymeric layer 4 defines the element that seals the union between the pieces to be connected.

[0014] The first male segment 2 insert has a diameter larger than the diameter of the second male segment 3, forming in this way an annular step 6 having a front face 7 that, once placed the insert in the tube or the fitting, is aligned with the plane of the front wall of the end of the tube or corresponding accessory. Preferably, the polymer layer 4 extends covering the front face 7 of said step 6 and the front face 8 of the segment 3 of the insert 1.

[0015] Example of application of FIG. 3, which shows the insert 1 placed in a connecting accessory 9, where it can clearly see the union among the front face 7 of the step 6, formed by the difference of diameters from the first male segment 2 and the second male segment 3 of the insert 1, and the front face 10 of the tubular section of the accessories 9 in which the insert is placed.

[0016] In practice, the elastomeric polymer used for the layer 4 is thermoplastic, and preferably PTFE (polytetrafluoroethylene) that includes various properties appropriate to the purpose of the insert for being practicable, almost inert, does not react with other chemical substances except in very special situations, has very low friction coefficient and great impermeability, is an electrical insulator, extremely flexible, is not altered by the action of the light, and is resistant to extreme temperatures. In addition, it is prevented the possibility of forming a polymer coating as a painting bath that will reach a sufficient thickness to ensure its sealing function of the connections. In addition, the sealing element defined by the layer 4 can be a coverage that later may require a curing, as also an electrolytic bath, or treatment of similar characteristics. Irrespective of the material used, the layer 4 can cover partially or totally the insert 1.

[0017] Meanwhile, in an embodiment, the main body of the insert, i.e. the first male segment 2 and the second segment 3 without the layer 4, are formed by a single metal piece, and the material to use may be, for example, brass, copper, iron, stainless steel, among other possibilities.