MXPA06007947A - Structured foam pig - Google Patents

Abstract

The present invention relates to a device intended to be passed through a pipeline of variable diameter, propelled by a liquid flowing inside said pipeline. The device has an elongated cylindrical body (2) made of polymer foam, with a number of deep channels (5) equally spaced from each other, coiled around the length of the cylindrical body (2) of the pig (1), beginning close to one end of the body (2) and ending close to the other end. These ends have a basically bulled-nosed shape, conferring a symmetrical aspect. Structural cleaning elements (6), not interconnected, are inserted inside the cylindrical body (2) of the pig. They are made of elastomeric material and have a central core (7) with spiral scraping extensions (8) of the same number as the deep channels (5) in the body (2) of the pig (1). The spiral scraping extensions (8) are at an angle to the axis of the cylindrical body (2) of the pig (1) as well as to the scraping extensions (8) of the adjacent modules, inasmuch as they follow the configuration of the spiral channel (5).

Description

STRUCTURED FOAM SCRAPER FIELD OF THE INVENTION The field of the present invention relates to a device designed to be passed through a pipe of variable diameter, driven by a liquid flowing into the pipe.

. TECHNICAL BACKGROUND All major industries use pipes to transport a wide range of liquids. The use of devices that can be driven by a liquid flowing inside a pipe is well known, with such devices frequently described by the. English term for 'pipe scraper'. The term "pipe scraper", or simply "scraper", is commonly used in industry. Scrapers are used when a pipe is constructed, as well as during the working life of such pipe. The scrapers are typically comprised of a rigid metal body that serves as a support for at least two discs and / or flexible scraper containers, which They work to drive the scrapers, or they help scrape. The scrapers can also be spherical. The scrapers can be used to fill or empty pipes, or to separate different products that flow in a pipe, simple. A frequent event, depending on the flow inside the pipe, which can complicate situations of operation, or even lead to risks, is the formation of deposits on the internal wall of the pipe. In some cases, these deposits can form very slowly, and can be adhered gently and loosely. In such cases, these can be easily removed after they are presented. In other cases, the encrustation may be more extensive, and even occasionally obstruct the flow of liquid completely. In both cases, a scraper is used to remove the material deposited inside the pipe, to clean it. The scrapers are passed through the interior of the pipe using a standard program used by operators in the industry. This program varies according to the severity of the deposit process. The aforementioned scrapers have been used for a long time, and are efficient when the internal diameter of the pipe is constant. However, a conventional scraper may have certain drawbacks. An example is when the body Scraper metal breaks inside the pipe. The pieces of the broken body can be dispersed inside the pipe, or in the joints of the pipes, or even in the valves. Another possible example involves the ability of the scraper to pass through very narrow bends in the pipe, which can cause a scraper with a rigid body to get stuck. Scrapers made of non-rigid components are not subject to the above drawbacks. In the case of a structural failure, since the building material is usually elastomeric, a second scraper can always pass to dislodge the elastomer pieces that may be floating freely within the pipe and whose evacuation has not controlled the flow of liquid. Meanwhile, pipelines that transport liquids have recently become in use with variable nominal diameter pipe. In these cases, the scrapers used so far have proved inadequate, since a scraper can be built with a sufficient diameter for a specific internal diameter for a section of the pipe, but can be stuck in another section with a smaller internal diameter , or the scraper may lose its thrust if the inner diameter It is larger, so the liquid flows through the annular space between the container and the pipe. A typical example of a situation involving the above cases would be an elastomeric scraper with cleaning vessels of limited flexibility. As soon as the diameter of the pipe is reduced to a size consistent with the flexibility of the scraper containers, there will be no problems. However, if the diameter is considerably smaller, the flexibility of the containers will not allow them to change size sufficiently, and the scraper will get stuck. Therefore, the need has arisen to develop scrapers capable of cleaning pipes of variable diameters. Most innovations focus on containers adapted to the scraper, in terms of the physical characteristics of the material from which they are made, as well as of the new configurations capable of responding to changes in diameter. Among the specialists, these scrapers are known as scrapers of multiple sizes. A very common and disadvantageous phenomenon involving scrapers with so-called multi-size sealers is that the sealants may become misaligned with respect to the pipeline ("nose"). "below"), due to the excessive flexibility of the sealants Another type of scraper within the current technique is known as a "foam scraper", giving it this name because it is produced from a polymeric foam, for example polyurethane foam. Compared to the types of scrapers described above, a foam scraper is characterized by its reasonable strength and the ease of changing its shape.The conventional "foam scrapers" are shaped with a concave hollow at one end, with In order to act as a surface to concentrate the pressure caused by the propellant liquid, and with the other end have a regularly convex projection.A feature of this type of scraper is that it can change shape widely.This change in shape makes it less efficient to remove hard deposits, and splinter more easily due to the lower resistance of the material from which it is made, what can or Do not cause it to get stuck inside the pipe. These drawbacks may be acceptable in the case of removable deposits smoothly and easily, and thanks to the low cost of manufacturing these scrapers.

The search for a more efficient cleaning of the interior of the pipes has progressed using scrapers made of this material. Purposes focused on increasing the abrasivity where the scraper comes into contact with the inner wall of the pipe include modification of the surface texture of the scraper body, creation of inserts of outer bristles around the scraper body, or a rough surface with various configurations, such as diamond shapes, for example, in U.S. Patent 3,602,934 (Acushnet Company) and U.S. Patent 4,242,771 (Kenneth M. Knapp), or by overlapping different materials in other formats such as in U.S. Patent 5,895,619 (Knapp), or even by coating the entire scraper with a layer of tiny bristles, metal or other material, as shown in U.S. Patent 4,016,620 ( Pipeline Dehydrators, Inc.). With respect to the increase in cleaning efficiency, abrasiveness can have risks for the internal wall of the pipe, especially in the case of flexible pipes with a thin inner layer of stainless steel. The objectives related to the ways of increasing the scraping capacity that have pointed to the bristles or to the change of the surface texture, imply only certain thin strips, wound around the length of the outer part of the cylindrical body of the scraper. Examples of this type of scraper are: U.S. Patent 4,720,884 (T. D. Williamson, Inc.) U.S. Patent 5,384,929 (TD Delaware, Inc.) and U.S. Patent 5,533,224 (Kenneth M. Knapp). Therefore, the need arose for a scraper that could move back and forth within the pipe, with scraper components capable of producing high contact stress with the inner wall of the pipe, responding to changes in the direction of the scraper without import the reason, and without damaging the inner part of the pipe.

BRIEF DESCRIPTION OF THE INVENTION The present invention relates to a device that can be passed through the interior of a pipe of variable diameter, driven by a liquid flowing inside the pipe. The device, hereinafter referred to as the "scraper", has an elongated cylindrical body, made of polymeric foam, with ends that are tipped like bullet, resulting in a shape symmetric The symmetry facilitates the trip back and forth within the pipe. Several deep channels, equally spaced from each other, are created in the cylindrical body of the scraper. Each of these deep channels is wound around the entire length of the cylindrical body of the scraper, start near its end and end near the other end. The spiral curve of each channel allows the entire internal perimeter of the pipe through which the scraper passes to be covered. The structural cleaning elements are inserted in the cylindrical body of the scraper, which are not interconnected. Because these elements are separated, the scraper can be lengthened when it passes from a larger diameter tube to one with a smaller diameter. These are made of elastomeric material and have a central core with spiral scraping extensions that are also counted as the deep channels in the body of the scraper. These spiral scraping extensions are of a length almost equal to the radius of the cylindrical body of the scraper, and they move angularly with respect to the axis of the cylindrical body of the scraper as well as with respect to the scraping extensions of the adjacent modules, since they follow the configuration of the spiral channel.

BRIEF DESCRIPTION OF THE DRAWINGS The characteristics of the structured foam scraper of the present invention will be apparent from the following detailed description, only as an example thereof, which should be read in conjunction with the accompanying drawings which form an integral part of this document. Figure 1 is a side view of the body of a scraper, according to the present invention. Figure 1A is a perspective view of the scraper body of Figure 1. Figure 2 is a front view of a structural cleaning unit, according to the present invention. Figure 2A is a side view of the structural cleaning unit of Figure 2. Figure 2B is a perspective view of the structural cleaning unit of Figure 2. Figure 3 is a side view of the complete scraper, in accordance with FIG. with the present invention. Figure 3A is a perspective view of the complete scraper of Figure 3.

DETAILED DESCRIPTION OF THE INVENTION The detailed description of the structured foam scraper of the present invention will be given according to the identification of the components of the invention, based on the figures described above. The present invention relates to a structured foam scraper capable of: operating on pipes formed of sections of tubes, which may be flexible and / or may have variable diameters; travel back and forth within the previous pipes; Efficiently scrape the deposits from inside the pipe. Figure 1 is a side view of the scraper body of the present invention, generally indicated by (1). This has a cylindrical body (2) elongated and substantially cylindrical, with two ends of the same configuration, formed of a bullet-shaped surface (3) leading to the cylindrical surface of the body (2) and a conical surface (4) that follows the bullet-shaped surface (3). The union of the bullet-shaped surface (3) and the conical surface (4) forms a nose on each end of the cylindrical body (2). This configuration facilitates the trip back and forth of the scraper inside the pipe. The details described above may also be associated with Figure 1A, which is a perspective view of the scraper of the present invention. The cylindrical body (2) of the scraper (1) has various channels (5), at a right angle to the axis of the cylindrical body (2) and equally spaced from each other. The present embodiment shows four channels (5), each of which is wound around the length of the cylindrical body (2) of the scraper (1), which starts near one end of the body and ends near the other end. The channels (5) have a spiral, or helical, spaced so that they are distributed on the cylindrical body (2) so that they cover 'at least the internal circumference of a pipe, ie 360 °. Figures 2, 2A and 2B show only one of the various structural cleaning elements, generally indicated by reference (6). Made of polyurethane elastomer, for example, these are located inside the cylindrical body (2) of the scraper (1). Each of the structural cleaning elements (6) comprises a central cylindrical structural element (7), located in the core of the cylindrical body (2) and aligned with "the longitudinal axis of this body." The essentially rectangular scraping extensions (8) are wound around the central structural element (7), counting them as the channels (5) on the cylindrical body (2) of the scraper (1) The scraping extensions (8) are not joined to the polyurethane foam of the body (2), a construction feature that minimizes chipping of the scraper body (2) (1). 8) is separated by an angle (a) between them, as shown in figure 2. In the present embodiment, since there are four channels (5), the angle (.) Is at least 90 °. the scraping extensions (8) is also separated by an angle (ß) as shown in figure 2A, with respect to the cylindrical body axis (2), in order that the shorter longitudinal sides of the extension (8). ) are at right angles to the sides of the spiral channels (5).

In the present embodiment, the angle (ß) is at least 60 °. The structural cleaning elements (6) are not interconnected, which allows the scraper (1) to be extended without allowing the body (2) of the scraper (1) to be chipped by the pressure of the liquid provided that the internal diameter of the pipeline is reduced. On the other hand, the fact that the structural cleaning elements (6) are not interconnected allows the scraper (1) to travel through curved pipes with short radius flexures, and also allows the body (2) of the scraper (1) to elongate when traveling through pipes with variable diameters, more specifically when the diameter of the pipe decreases, for example, from 15.2 cm to 10.1 cm (6 inches to 4 inches). The structural cleaning elements (6) are first adjusted and aligned within a mold of the cylindrical body (2) of the scraper (1), and thereafter they are encapsulated by injection of polymeric foam. Because the scraping extensions (8) of the structural cleaning elements (6) are made of elastomeric material, they are flexible with respect to their longitudinal axis. This flexibility is essential if the direction of travel changes, or if there is a displacement caused by blocking. Since the diameter of a scraper (1) is normally slightly smaller than that of the pipe to be cleaned, when the scraper (1) travels within a pipe, all the scraping extensions (8) during the movement are flexed in the same direction with respect to the direction of movement. Each time the direction changes, all the scraping extensions (8) are flexed in the new direction without losing their cleaning effectiveness and without causing blockage.

Figures 3 and 4 show the final appearance of the scraper (1) of the present invention, with the structural cleaning elements (6) in place within the cylindrical body (2) of the scraper (1). Heretofore the description of the structured foam scraper of the present invention should be considered only as a possible embodiment thereof, and any specific feature introduced therein, should be understood only as something described in order to make understanding easier. Accordingly, such features should not be construed in any way as strictly restrictive to the present invention, with any limitation to it falling within the scope of the following claims.

Claims (12)

1. Structured foam scraper, designed to be passed through the interior of a pipe in order to facilitate the scraping of the internal part of the pipe when it is driven by a liquid flowing inside the pipe, which comprises: a foam body polymer, elongate and substantially cylindrical including a plurality of channels extending at right angles to a longitudinal axis of the cylindrical body, the channels are equally spaced around the cylindrical body and are wound around the cylindrical body; and two ends, each end includes a bullet tip surface, connected to the cylindrical body and a conical surface provided from the bullet-shaped surface, each of the cylindrical body channels beginning near one of the two ends and ends near the other end, of the two ends; and a plurality of elastomeric cleaning structural elements, located within the cylindrical body, each of the plurality of elastomeric structural cleaning elements, including a central, cylindrical structural element and scraping extensions wound around the cylindrical structural element, the plurality of elastomeric cleaning structural elements are not interconnected with each other.

2. Structured foam scraper according to claim 1, wherein the channels have a spiral-spaced shape and are located in positions on the cylindrical body such that the channels combine to cover at least the entire internal circumference of the pipe.

3. Structured foam scraper according to claim 1, wherein the central structural element is located in a core of the cylindrical body.

. Structured foam scraper according to claim 1, wherein each of the scraping extensions is located within the channels.

5. Structured foam scraper according to claim 1, wherein each of the scraping extensions is capable of flexing in the same direction relative to the longitudinal axis of the scraping extensions when the scraper travels inside the pipe.

6. Structured foam scraper according to claim 1, wherein the number of scraping extensions of the structural cleaning elements is the same as the number of the channels of the cylindrical body.

7. Structured foam scraper according to claim 1, wherein the scraping extensions are provided with the same angle (a) between each of the scraping extensions and an adjacent scraping extension, wherein the angle is with respect to a circumference of the scraper. central cylindrical structural element.

8. Structured foam scraper according to claim 1, wherein each of the scraping extensions is provided at a same angle (ß) with respect to the longitudinal axis of the cylindrical body, so that the shorter longitudinal sides of the extensions are placed at right angles to the lengths of the spiral channels.

9. Structured foam scraper according to claim 1, wherein the scraper travel through curved tubes with short radius elbows and pipes with variable diameters, is facilitated because the structural cleaning elements are not interconnected.

10. Structured foam scraper according to claim 1, wherein the scraper is manufactured by hardening and aligning the structural cleaning elements within a mold, and then injecting polymeric foam into the mold.

11. Structured foam scraper according to claim 1, wherein the polymeric foam is polyurethane foam.

12. Structured foam scraper according to claim 1, wherein the elastomeric material is elastomeric polyurethane.