TECHNICAL FIELD

The subject matter described herein relates to multilayer pipes for transporting liquids, gases, and the like and more particular to multilayer pipes which comprises individual layers structured of polyethylene.

BACKGROUND

Generally, pipes are used to transport a wide variety of substances such as liquid, gases, or the like to a wide variety of locations. Conventional pipes which were made of steel or cast iron are now being replaced by plastic pipes. These pipes are manufactured of single layer film. With the advancement in technologies, the pipes are manufactured of various materials that exhibit better mechanical properties. Such pipes are capable of joints according to the requirements.

However, such pipes, being structured of single layer film, are less capable to mechanically withstand the stress exerted by the pressurized water or gases. Additionally, the single layer pipes are heavy and thus difficult to handle too. Further, the presence of only single layer makes the pipes prone to damage by aggressive chemicals such as ozone and chlorinated derivatives. Moreover, the single layer film lacks mechanical strength which reduces the overall efficiency of the pipes. Therefore, there is a need for pipes that overcome the above and other shortcomings present in conventional technologies. SUMMARY

The subject matter described herein relates to multilayer pipes for transporting liquids, gases, and the like and more particular to multilayer pipes which comprises individual layers structured of polyethylene.

In an embodiment of the present subject matter, the multilayer pipes are provided with at least three concentric layers.

In an embodiment of the present subject matter, the three concentric layers of the multi layered pipe includes upper, middle and lower layer. In an embodiment of the present subject matter, the layers (upper, middle and lower) use different grades of polyethylene.

In an embodiment of the present subject matter, the upper layer and lower layer are made of linear low density polyethylene (L.L.D.P.E.) and low density polyethylene (L.D.P.E.)

In an embodiment of the present subject matter, the middle layer is made of high density polyethylene (H.D.P.E.) wherein the middle layer is fabricated in warp and weft fashion.

In another embodiment of the present subject matter, the multilayer pipes are provided with at least five concentric layers.

In an embodiment of the present subject matter, the layers (five layers) use different grades of polyethylene designed in an alternate arrangement. In an embodiment of the present subject matter, the five layers are structured with alternate application of linear low density polyethylene (L.L.D.P.E.) & low density polyethylene (L.D.P.E.) and high density polyethylene (H.D.P.E.). In an embodiment of the present subject matter, the middle layer is woven with fabrics (in warp and weft fashion) on a circular loom.

In an embodiment of the present subject matter, the lower and upper layers are pasted to the middle layer by a pasting machine.

In an embodiment of the present subject matter, the layers are sealed together by a sealing machine.

In an embodiment of the present subject matter, the sealed layers are folded to result in pipes.

In an embodiment of the present subject matter, the objective of the present invention is to provide mechanically strong, lighter and efficient pipes for various applications.

BRIEF DESCRIPTION OF ACCOMPANYING DRAWINGS

The aforementioned aspects and other features of the present disclosure will be explained in the following description, taken in conjunction with the accompanying drawing, wherein:

FIG.l illustrates a cross sectional view of multi-layered pipe, according to one embodiment of the present subject matter.

FIG.2 illustrates a front view of a three layered pipe, according to one embodiment of the present subject matter.

FIG.3 illustrates a front view of a five layered pipe, according to one embodiment of the present subject matter. DETAILED DESCRIPTION

The embodiments of the present subject matter are described in detail with reference to the accompanying drawings. However, the present subject matter is not limited to these embodiments which are only provided to explain more clearly the present subject matter to the ordinarily skilled in the art of the present disclosure. In the accompanying drawings, like reference numerals are used to indicate like components.

Extruded pipes made of thermoplastic polymers are well known in variety of applications such as in the building industry for domestic water pipes, radiator pipes, floor heating pipes, in ship buildings, and the like. FIG.l illustrates a cross sectional view of a multi-layered pipe 100, according to one embodiment of the present subject matter. The term "multi-layered pipe" refers to structures defining a cavity there through for conducting a fluid, including, without limitation, any liquid, gas, finely divided solid, or the like. The wall of the multi-layered pipe 100 is structured with at least three concentric layers, in a preferred embodiment of the present subject matter. The shape of the pipe 100 is not restricted to any limited geometry until they define a passageway there through.

As illustrated in FIG.l, the multi-layered pipe 100 according to the present subject matter is provided with at least three concentric layers. The layers further include upper 102, middle 104 and lower layer 106. In a preferred embodiment of the present subject matter, these layers (upper, middle and lower) use different grades of polyethylene. In an embodiment of the present subject matter, the upper layer 102 and lower layer 106 are made of linear low density polyethylene (L.L.D.P.E.) and low density polyethylene (L.D.P.E.). The middle layer 104 fabricated in warp and weft fashion 108 is composed of high density polyethylene (H.D.P.E.), in an embodiment of the present subject matter. The high density polyethylene is defined by a density of greater or equal to 0.941 g/cm . The presence of high density polyethylene in the middle layer 104 strengthens the multi-layered pipes 100.

During manufacturing of the pipes 100, the high density polyethylene is used to manufacture tape by using extrusion machine, in an embodiment of the present subject matter. The tape is subsequently used to weave to make fabric. The weaving of fabric is done on a circular loom (not shown). The circular loom can be equipped with the electronic control systems to achieve high performances of the layers. The electronic control systems may include sensors, microcontrollers, and the like. In an embodiment of the present subject matter, the lower layer 106 and upper layer 102 are laminated on a lamination machine (not shown). The laminated lower layer 106 and upper layer 102 are pasted with the middle layer 104 woven with fabric to enfold the middle layer 104 with the upper layer 102 and the lower layer 106 (shown in FIG.2 also). The layers are pasted by a pasting machine (not shown), in an embodiment of the present subject matter. The pasted layers are folded and sealed by a sealing machine (not shown) in various shapes as per requirements, which subsequently results in pipes. The pipes 100 manufactured with such design are less heavy as the layers in the pipes 100 are woven with fabric and various grades of polyethylene. The multi-layered pipe 100, according to the present subject matter, facilitates easy handling with the pipes 100.

In another embodiment of the present subject matter, the multilayered pipe 100 includes five layers of different grades of polyethylene, as shown in FIG.3. The five layers are structured with alternate arrangement of linear low density polyethylene (L.L.D.P.E.) & low density polyethylene (L.D.P.E.) and high density polyethylene (H.D.P.E.). In the present embodiment of the present subject matter, the second and fourth layer of the five layered pipe is fabricated in warp and weft fashion. The first, third and fifth layers are subsequently laminated by the lamination machine thereafter which the first, third and fifth layers are subsequently pasted with the second and fourth layers woven with warp and weft fashion to finally results in pipes 100. The presence of five layers in the multilayered pipes 100 facilitates safe transmission of highly pressurized flow of water.

The multi-layered pipes 100 according to the present subject matter advantageously provide a pipe 100 capable of strongly withstanding the mechanical stress exerted by the pressurized water or gases. Secondly, the presence of at least three layers in the pipe 100 helps in protecting the pipe 100 against aggressive chemicals such as ozone and chlorinated derivatives. Additionally, the alternate layers may be provided with various additives which protect the layers from ultraviolet radiations. Further, the presence of woven fabric in middle layer makes the pipe 100 lighter in weight which provides easy handling of the pipes 100. Moreover, the advantage of multi layers (three or five layers) over single layer, as compared to prior technologies, boosts mechanical strength of the pipes 100 which increases the overall efficiency and life of the pipes 100 also.

Although the subject matter has been described with reference to specific embodiments, this description is not meant to be construed in a limiting sense. Various modifications of the disclosed embodiments, as well as alternate embodiments of the subject matter, will become apparent to persons skilled in the art upon reference to the description of the subject matter. It is therefore contemplated that such modifications can be made without departing from the spirit or scope of the present subject matter as defined.