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AssigneeSekisui Chemical Co., Ltd.
InventorsKoji Yamaguchi, Mitsuhide Nogami, Yasuo Yamabe, Masanori Nakamura, Katsuo Matsuzaka, Takehiro Yamada, Satoshi Koma, Kenji Mizukawa, Hideki Sakakihara, Toshihide Nonaka
Estimating the term…
A high-pressure composite pipe includes a pipe-shaped inner layer made of a synthetic resin, and a reinforcing layer made of a stretched polyolefin resin sheet and wound on an external circumferential surface of the inner layer, with a winding direction of the reinforcing layer being oriented at a predetermined angle relative to an axis of the pipe, and a method for joining high-pressure composite pipes each including a pipe-shaped inner layer made of a synthetic resin, a reinforcing layer made of a stretched polyolefin resin sheet and wound on an external circumferential surface of the inner layer, and an outer layer made of a synthetic resin and laminated on the reinforcing layer. A method for joining high-pressure composite pipes includes the steps of: heating and melting an end of each high-pressure composite pipe, flaring the melted end of each high-pressure composite pipe, with a diameter thereof gradually enlarging toward an end face thereof, and butting the flared ends of both flared high-pressure composite pipes together and fusing internal circumferential surfaces of their inner layers, with their reinforcing layers being turned outwardly.
A method for joining high-pressure composite pipes each comprising a pipe-shaped inner layer made of a synthetic resin, a reinforcing layer made of a crosslinked stretched polyolefin resin sheet and wound on an external circumferential surface of the inner layer, and an outer layer made of a synthetic resin and laminated on the reinforcing layer, which method comprises the steps of:
Dependencies are inferred from the claim text.
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From the US filing history. Foreign family members aren’t listed.
Layered products having a non-planar shape: tubular products
Using heated tools: with direct contact, e.g. using "mirror"
Joining or sealing of preformed parts , e.g. welding of plastics materials; Apparatus therefor: using mechanical means or mechanical connections,…
Using mechanical means or mechanical connections, e.g. form-fits: using extra joining elements, i.e. which are not integral with the parts to be…
Term ended 7 Sep 2021 (estimated)
The present invention relates to high-pressure composite pipes to be used as high-pressure-resistant pipes or hoses which require a high internal pressure resistance strength.
The present invention also relates to a method for joining a pair of high-pressure composite pipes.
With regard to pipes for transporting a medium like water and gas, steel pipes are conventionally employed as such. While steel pipes exhibit a high internal pressure resistance strength and an excellent creep resistance, they are poorly quakeproof and develop rust and corrosion. In these days, therefore, synthetic resin pipes such as unplasticized polyvinyl chloride (PVC) pipes and polyethylene pipes are frequently employed.
FIG. 1 schematically shows the structure of the apparatus used in Example 2 for manufacturing the high-pressure composite pipe according to the present invention.
FIG. 2 is a perspective view showing the structure of the high-pressure composite pipe manufactured in Example 2.
FIG. 3 is a perspective view showing the structure of the high-pressure composite pipe manufactured in Example 3.
Hereinafter, the present invention is specifically described by means of non-limitative Examples of the present invention.
Manufacture of a Reinforcing Layer Sheet
A high-density polyethylene (melting point 135° C., melt index MI=1 g/10 mins.) was used as the polyolefin. While the high-density polyethylene was kneaded at 200° C. in a co-rotating twin-screw extruder, 3 parts by weight (relative to the high-density polyethylene) of triallyl cyanurate as a cross-linking auxiliary and 3 parts by weight of benzophenone as a photo-polymerization initiator were added and evenly kneaded into the high-density polyethylene. The mixture was extruded from a T-die to give a 3-mm-thick polyolefin sheet.