MX2009010612A

MX2009010612A - Connector for tubing, containing a plastic insert.

Info

Publication number: MX2009010612A
Application number: MX2009010612A
Authority: MX
Inventors: Eduardo Santos Burgoa Marquez
Original assignee: Grupo Rotoplas S A De C V
Priority date: 2009-10-01
Filing date: 2009-10-01
Publication date: 2011-04-19
Also published as: GT201200018U; UY32907A; WO2011039623A2; PE20131154Z; CR20120165A; PE20131155Z; BR212012007531U2; MX337447B; ECSP12011797A; PE20120890Z; AR078484A1; WO2011039623A3

Abstract

The invention relates to a connector for tubing, consisting of a body and a screw insert, the material forming the insert being a plastic material with high mechanical resistance and the material forming the body being a thermoplastic resin. The insert is partially or completely housed in the body of the connector, tightly coupled thereto by means of an anchoring system consisting of at least one circular or polygonal ridge formed on the outer face of the insert, the ridge(s) peripherally surrounding the cylindrical wall of the insert. The separation between the ridges creates at least one groove into which the thermoplastic material forming the body of the connector penetrates, enabling the long-term tightness of the connection. The structure of the connection can include a reinforcement ring which provides the connector with a resistance higher than that provided solely by the insert material.

Description

CONNECTOR FOR PIPE CONTAINING A PLASTIC INSERT FIELD OF THE INVENTION The illustrated embodiments of the present invention relate in general to connectors for tubing and, more particularly, to plastic connectors of the type having a threaded plastic insert.

BACKGROUND OF THE INVENTION Plastic pipes for transporting fluids are increasingly used, because they are easier to handle than metal pipes, are resistant to corrosion, have light weight, are easy to mold and have a low cost. To join the components of the pipe it is common to use connectors, preferably made of a material compatible with the plastic of the pipe. The most commonly used plastic materials for this purpose are thermoplastic polymers, such as polypropylene or other polyolefins, capable of making extremely reliable connections through a thermofusion bonding process.

The connections that are joined by thermofusion usually require the integration of the thermoplastic material with a threaded metal insert, since the metal component has high resistance to the action of torque when connecting with threaded fittings, and can withstand pressures and temperatures of work elevated. However, the selection of the metal and its coating, where appropriate, the high weight and difficulty for molding the metal inserts, are important disadvantages that can be overcome by replacing the metal insert with a plastic insert. The latter must obviously have properties of resistance to the action of torque when connecting with other threaded fittings, must be compatible with the external plastic material that forms the body of the connector and be resistant to the chemical agents that may be driving. Likewise, the coupling between the insert and the body of the connector must be highly reliable in order to avoid liquid leakage when working under elevated conditions of temperature and pressure.

There are currently several proposals for connectors with plastic inserts. For example, U.S. Patent No. 7,469,935 describes a pipe connection formed by two layers of different materials. The inner layer is in contact with the liquid that is transported, and is made of a plastic material that withstands high temperatures. Although the connector integrates two types of plastic with different properties, it does not include threaded means in the insert for coupling to threaded pipe, nor reliable means of coupling between the insert and the body of the connector.

US 2003/0184085 patent application relates to an adapter for connecting two pipe segments. The adapter includes: a) an insert made of a rigid material, such as bronze or other metallic material, or even a rigid plastic material; and b) a receiving body made of a soft plastic material, such as CPVC. The insert has a female internal thread to receive a thread from a pipe. Advantageously, the connector has coupling means between the insert and the receiving body, consisting of a plurality of projections formed on the external part of the insert, which when coupled with the receiving body, are housed in a series of grooves formed in the receiving body. To help the insert remain in a fixed position during engagement with other threaded fittings, it is proposed that the protrusions of the insert have a polygonal shape, for example, hexagonal.

A disadvantage of the connector described in the application US 2003/0184085 is that the securing between the insert and the receiving body is done mechanically, by means of a complex system of projections and annular grooves, which makes both its manufacture and its installation difficult. It also has an aesthetic disadvantage, since the insert is not completely embedded in the receiver body, but a part of the insert is unprotected and would be visible in the connection. Evidently, the insert will be exposed to environmental conditions that can shorten its useful life. In particular, one of the embodiments of this patent application describes an insert that is completely imbedded in the recipient body. However, in this mode, the internal thread to receive the pipe is actually in the insert and in the same connector. Consequently, the thread of the pipe would necessarily have to be coupled to two pieces, sacrificing the tightness of the connection. Moreover, it is known that the material of the receiving body is not sufficiently resistant to the action of the torque, so that the threading will be susceptible to being swept, at least in the threaded portion that corresponds to the receiving body.

The patent 7,234,906 protects an insert with internal thread, the insert is designed to be housed in a wrapping material. The insert has male-type cords on the outer surface, to be attached to the surrounding material. It also includes projections that secure the insert inside the enclosing material and prevent the relative rotation of the insert when it receives another threaded accessory. In this case, the insert only imparts a thread resistant to the wrapping material, but said wrapping material is not a thermofusable body.

U.S. Patent No. 5,879,115 discloses a method for attaching a plastic insert to a plastic base having a recess formed in said base. The insert has projections in circular arrangement, separated from each other, said projections are adjusted under pressure within the plastic base. When the two plastics melt, the plastic of the projections flows into the spaces, and the plastic of the base flows into the spaces. This causes the securing of the two components, preventing the relative rotation of one with respect to the other. However, this assurance would not be sufficient to resist torque when the insert engages with other threaded fittings, in fact, the patent does not mention or suggest the existence of a threaded insert.

None of the documents describes a connector in which the means of connection between the insert and the body are strong enough to resist torque and also an anchoring system between both parts effective to prevent sliding. There is, therefore, a need for a pipe connector that overcomes all the drawbacks of connectors developed in the past.

SUMMARY OF THE INVENTION In accordance with the present invention, a connector device for pipe is presented, suitable for use under extreme conditions of temperature and pressure. The connector is constituted by a body of the connector and an insert, wherein the body constitutes a housing for the insert. The body is formed in a thermoplastic material, while the insert is made of a material with high mechanical strength and also able to withstand high temperatures, so that the combination of the two types of plastics gives this connector properties superior to those of that would be achieved by using each plastic separately. The connector is formed by overinjection of the thermoplastic material on the insert, which allows to achieve a tightness of the connection in the long term. In addition, the two components forming the connector are secured together by a highly effective anchoring system, formed by a plurality of ridges on the outer wall of the insert, which engage with a corresponding plurality of grooves in the inner wall of the connector body. .

A type of male connector is shown, and a second type of female connector, the latter includes within its structure a reinforcing ring that gives the connector a resistance to torque greater than that offered by the insert material alone, without need to use a large amount of material in the insert, which saves manufacturing costs.

Provide a pipe connector made of a corrosion resistant material, lightweight, low cost, and that has resistance to high pressures and temperatures.

Provide a connector for tubing in a plastic material, which is resistant to the action of torque when screwing with other threaded fittings.

Provide a connector made of a thermoplastic material to be joined with pipe of the same material by thermofusion and thus achieve an extremely reliable coupling between the pieces.

Provide a pipe connector formed by two components, one internal and one external, where both components are joined by a highly effective anchoring system to prevent the internal component from being swept or slid with respect to the external component.

Provide a connector for pipes with plastic insert, resistant to leakage when transporting fluids at high pressures and temperatures.

BRIEF DESCRIPTION OF THE DRAWINGS OR FIGURES The above aspects and many of the concomitant advantages to this invention will be better understood when the following detailed description is consulted and considered in conjunction with the accompanying drawings, in which.

Figure 1 is a perspective view of the male type connector of the present invention.

Figure 2 shows a perspective view of the female type connector of the present invention.

Figure 3 shows a longitudinal section of the male connector of the present invention.

Figure 4 shows a side perspective view of the insert of the male connector.

Figure 5 shows a longitudinal section of the female type connector of the present invention.

Figure 6 shows a perspective view of the insert of the female connector.

Figures 7 and 8 represent partial cuts of the female connector that allow to observe alternative reinforcement modalities in the female insert.

Figure 9 represents a rear perspective view of an alternative embodiment of the anchoring system in the female insert.

Figure 10 shows a rear perspective view of another alternative embodiment of the anchoring system in the female insert.

DETAILED DESCRIPTION OF THE PREFERRED MODALITIES Figures 1 and 2 show, respectively, a perspective view of male type connector (1) and female type connector (2). Both connectors are constituted by a body (3) of the connector and a threaded insert (4).

The insert (4) and the body (3) are formed of different plastic materials. The material that forms the insert (4) is a plastic with high mechanical strength and capable of long-term high temperatures of approximately 95 ° C. The plastic that forms the body (3) is a thermoplastic resin that allows the union by thermal means to a pipe made of a compatible material.

The plastic that forms the body of the connector is selected, without being limited to, the following materials: PE, PP, PPR or other polyolefins; PVC, CPVC and engineering plastics, or any other thermoplastic or thermosetting resin.

The plastic that forms the insert is selected, without being limited to, the following materials: Noryl (mixture of polyphenylene oxide (PPO) and polystyrene (PS), owned by the company SABIC), polyphenylene oxides, polysulfones, acetals, polycarbonates or any other engineering plastic, Noryl being the material used in the preferred embodiment.

Firstly, the male type connector (1) will be described based on figures 3 and 4, which show, respectively, a longitudinal section of the connector and a side perspective view of the insert. It can be seen that this connector has a male insert (4) with a front portion (5) projecting from the body (3), said front portion having an external thread for coupling to connections and / or accessories with internal thread. The male insert (4) also has a back portion (6), which will be embedded in the body (3) of the connector, in close coupling with it.

The anchoring system between the body (3) and the back portion (6) of the male insert (4) will be explained below: The insert (4) has one or more ridges (7) formed on the back portion (6), specifically on the external face of the insert, said ridges (7) preferably circumferentially surrounding the cylindrical wall of the insert (4). The separation between the crests (7) gives rise to a plurality of circular grooves or grooves (9) for insertion. The pattern of crests and grooves mentioned above gives rise to a highly effective anchoring system at high temperatures and pressures.

Additionally, the base (10) of the insert, located at the rear end of said piece, may include one or more ridges (11) and grooves (12) oriented perpendicularly in relation to the crests (7) of the cylindrical wall of the insert ( 4) . These crests (11) and grooves (12) constitute a posterior anchoring system that reinforces the coupling between the pieces.

Additionally, each of the crests (7) can have a plurality of grooves (13) formed, preferably, in all the periphery of the crest (s) (7), said grooves (13) are oriented in the longitudinal axis. The grooves (13) allow a better resistance to the action of the torque, preventing the insert from sliding with respect to the body of the connector when connecting with threaded fittings.

The body (3) of the male connector houses only the back portion of the insert, and is made of a plastic material, so that upon overinjection over the insert, the plastic material of the body flows into the grooves (9) and (12) of the body. insert, and towards the grooves (13) of the insert, achieving a hermetic coupling.

Next, the female type connector based on FIGS. 5 and 6 will be described.

In the case of the female type connector, the insert (4) is completely housed in the body (3) of the connector. The insert (4) has an internal threading (14) and on the external face has a pattern of ridges (7) and grooves (9) similar to that described for the insert (4) of the male connector mode. The crests (7) are on the outer wall of the insert, and each ridge (7) may include a plurality of ridges (13) at the periphery of the ridge (s). One or more crests (11) and one or more grooves (12) may also be present in the base (10) of the insert.

In the preferred embodiment, the female insert (4) has a ridge-free portion (15), adjacent to the front end of the part, and of smaller thickness to the rest of the insert, said portion constituting a recess for a reinforcing ring (16). ). The ring (16) surrounds the front portion of the insert, without protruding from the body (3) of the connector, as seen in figure 5. Preferably, the outer face of the ring (16) has at least one ridge formed, and grooves adjacent to the ridge (s), to achieve effective anchoring between the ring (16) and the body (3) of the connector.

As an alternative, instead of the reinforcing ring (16) being in the front part of the insert, it is embedded in the same insert (see figure 7). As another alternative, the reinforcing ring (16) is embedded in the body of the connector (see figure 8). The advantage of having the ring completely covered is that you get a greater contact surface between the two plastic materials, improving the tightness in the connector.

The reinforcement ring (16) gives the insert a torque resistance even greater than that which would be achieved by using only the plastic material. Obviously, the resistance to torque is also a function of the thickness of the material that forms the connector, but as the reinforcement ring exists, superior strength is achieved without the need to increase the amount of material either in the insert or in the body. The result is a saving of plastic material and therefore a lower cost of the product.

The reinforcement ring (16) can be made of a material such as stainless steel, nickel-plated brass, bronze, carbon steel, aluminum, duralumin, or any other corrosion-resistant metal material that is compatible with both plastics .

The body (3) of the female connector is made of a plastic material, so that when overinjected into the insert, the plastic material of the body flows into the grooves (9) and (12) of the insert, and towards the grooves (13) of the insert, achieving a hermetic coupling.

In the two embodiments of the connector, the pattern of grooves and ridges described above offers an additional advantage: the resulting structure is highly resistant to leakage, since the water or any fluid that is transported through the pipeline, before leaving through the union between the insert and the body, would have to follow a long path given by the set of ridges and grooves.

To reinforce the anchoring system, both the male insert and the female insert may include at the rear end one or more protuberances (17), such as those seen in figures 9 and 10. In the embodiment of figure 9, the insert includes eight protuberances ( 17) spaced apart equidistantly around the circumference of the base of the insert. In the embodiment of Figure 10, the insert includes four protrusions (17) spaced apart at about ninety degrees around the circumference of the base of the insert.

The modalities described above for the anchoring system of circular ridges and grooves, can be replaced with other types of anchoring. For example, the crests of the plastic insert can have a polygonal shape, for example octagonal, hexagonal, pentagonal, square, among others. The fact of having different faces prevents the insert from rotating with respect to the body and "barges" when the piece is screwed with other accessories, even without the presence of grooves.

The resulting connector of the present invention is capable of withstanding working temperatures from 5 ° C to 95 ° C, and working pressures up to 20 kg / cm2, which makes it suitable for use in piping systems for the conduction of fluids liquid or gaseous in residential, commercial and industrial facilities.

While preferred embodiments of the invention have been illustrated and described, it will be appreciated that various changes may be made therein without deviating from the spirit and scope of the invention. For example, the male-type connector may also include a reinforcing ring surrounding the insert, either embedded in the insert or in the same body of the connector, similar to the female-type connector. Moreover, the ring may have ridges on the inner face, or on both faces. The present invention is applicable to a wide range of connectors, for example, connectors type male, female type, male-female, female-female, male-male, elbow 90 °, elbow 45 °, connection "T", connection "Y" and straight connector.

Claims

CLAIMS;

1. A connector for tubing constituted by a body of the connector and a threaded male insert, wherein the insert and the body are formed of different plastic materials, characterized in that the material forming the insert is a plastic with high mechanical strength and the material that forms the body is a thermoplastic resin, the insert has a front portion with an external thread, and a rear portion that is housed in the body of the connector, in close coupling therewith by an anchoring system consisting of one or more ridges circular or polygonal formed on the outer face of the back portion of the insert, the crest (s) circumferentially surrounds the cylindrical wall of the insert and the spacing between the ridges results in one or more circular insertion grooves or grooves.

2. The pipe connector according to claim 1, wherein the ridge (s) surrounding the cylindrical wall of the body has a plurality of grooves oriented on the longitudinal axis.

3. The pipe connector according to claim 2, wherein the grooves are formed on the entire periphery of the crests of the cylindrical wall of the insert.

4. The pipe connector according to claim 1, wherein the base of the insert includes a back anchoring system consisting of one or more circular ridges and circular grooves oriented perpendicularly to the crests of the cylindrical wall of the insert.

5. The pipe connector according to claim 4, wherein the circular ridge (s) of the base of the insert have one or more protuberances.

6. A connector for tubing constituted by a body of the connector and a female-type insert with internal thread, wherein the insert and the body are formed of different plastic materials, characterized in that the material forming the insert is a plastic with high mechanical strength and the material forming the body is a thermoplastic resin, the insert is completely housed in the body of the connector, in close coupling with it by an anchoring system consisting of one or more circular or polygonal ridges formed on the outer face of the rear portion of the insert, the ridge (s) circumferentially surrounds the cylindrical wall of the insert and the spacing between the crests results in one or more circular insertion grooves.

7. The pipe connector according to claim 6, wherein the ridge (s) surrounding the cylindrical wall of the body has a plurality of grooves oriented on the longitudinal axis.

8. The pipe connector according to claim 7, wherein the grooves are formed on the entire periphery of the crests of the cylindrical wall of the insert.

9. The pipe connector according to claim 6, wherein the base of the insert includes a back anchoring system consisting of one or more circular ridges and circular grooves oriented perpendicularly to the crests of the cylindrical wall of the insert.

10. The pipe connector according to claim 9, wherein the circular ridge (s) of the base of the insert have one or more protuberances.

11. The pipe connector according to claim 1, wherein the connector further has a reinforcing ring concentric to the same connector and which is surrounding the insert, either embedded in the insert or in the same body of the connector.

12. The pipe connector according to claim 6, wherein the connector further has a reinforcing ring concentric to the same connector, on the front thereof.

13. The pipe connector according to claim 12, wherein the reinforcing ring is coupled to the female insert in a recess located on the outer face of the insert, adjacent to the front end of the part, and of less thickness to the rest of the insert, so that the ring surrounds the front portion of the insert, without protruding from the body of the connector.

14. The pipe connector according to claim 12, wherein the reinforcement ring is embedded in the same insert.

15. The pipe connector according to claim 12, wherein the reinforcing ring is embedded in the body of the connector.

16. The pipe connector according to claim 11 or 12, wherein the ring has formed at least one circular ridge, and grooves adjacent to the ridge (s) of the ring,

17. The pipe connector according to claim 16, wherein the circular ridge (s) of the ring are on the outer face thereof.

18. The pipe connector according to claim 11 or 12, wherein the reinforcing ring is made of a corrosion-resistant metal material.

19. The pipe connector according to any of claims 1 and 6, wherein the thermoplastic resin forming the connector body is selected from the following materials: PE, PP, PPR or other polyolefins; PVC, CPVC and engineering plastics, or any other thermoplastic or thermoplastic resin.

20. The pipe connector according to any of claims 1 and 6, wherein the plastic forming the insert is selected from the following materials: Noryl, polyphenylene oxides, polysulfones, acetals, polycarbonates or any other engineering plastic.

21. The pipe connector according to the claim 18, where the metallic material of the ring is selected from stainless steel, brass with nickel coating, bronze, carbon steel, aluminum and duralumin.

22. The pipe connector according to any of claims 5 and 10, wherein the insert includes four protrusions spaced apart at about ninety degrees around the circumference of the base of the insert.

23. The pipe connector according to any of claims 5 and 10, wherein the insert includes eight protrusions spaced apart equidistantly from one another around the circumference of the base of the insert.

24. The pipe connector according to any of claims 1 and 6, wherein the ridges on the outer face of the insert have an octagonal, hexagonal, pentagonal or square shape.

25. The pipe connector according to claim 1, wherein the connector is part of a connection device that is selected from the following types: male-female, male-male, 90 ° elbow, 45 ° elbow, "T" connection , "Y" connection and straight connector.

26. The pipe connector according to claim 6, wherein the connector is part of a connection device that is selected from the following types: female-female, male-female, 90 ° elbow, 45 ° elbow, "T" connection , "Y" connection and straight connector.