The invention relates to production of long spiral-welded large polymer products, as required for pipelines production, chemical, oil and gas and petrochemical industries, agricultural complex and utility services. The object of the invention is to create variants of spiral-welded polymer product with a cellular wall, having the internal or external, or internal and external uniform smooth walls with little material consumption, weight and cost. It should allow making products on site due the use of a thin-walled, lightweight, flexible profile. The object is solved owing to fact that a long hollow thermoplastic profile is used in spiral-welded polymer products, wherein the cross-section of the profile has a form of a closed geometric figure with a convex part having essentially the semi-ring shape and flat part that are connected each other, forming the convex and flat parts of the external surface of the profile, respectively.

The invention relates to production of long spiral-welded large polymer products, as required for pipelines production, chemical, oil and gas and petrochemical industries, agricultural complex and utility services. The object of the invention is to create variants of spiral-welded polymer product with a cellular wall, having the internal or external, or internal and external uniform smooth walls with little material consumption, weight and cost. It should allow making products on site due the use of a thin-walled, lightweight, flexible profile. The object is solved owing to fact that a long hollow thermoplastic profile is used in spiral-welded polymer products, wherein the cross-section of the profile has a form of a closed geometric figure with a convex part having essentially the semi-ring shape and flat part that are connected each other, forming the convex and flat parts of the external surface of the profile, respectively.

A method and composition of making polymer products from thermoplastic polymers by melt processing. Cross-linked polyethylene are mixed with at least one thermoplastic matrix polymer to form a polymer composition which is melt-processed. The cross-linked polyethylene is formed by a finely divided powder with particles having a screened size of less than 600 μm and a D.sub.50 of 200 to 400 μm. Cross-linked polyolefin can be used in a cost-effective and simple manner so that products generally considered a waste, such as scrapped cross-linked polyethylene pipes or unused cross-linked polyethylene discarded in e.g. pipe making processes, can be recycled and used as a starting material for polymer products.

A method and composition of making polymer products from thermoplastic polymers by melt processing. Cross-linked polyethylene are mixed with at least one thermoplastic matrix polymer to form a polymer composition which is melt-processed. The cross-linked polyethylene is formed by a finely divided powder with particles having a screened size of less than 600 μm and a D.sub.50 of 200 to 400 μm. Cross-linked polyolefin can be used in a cost-effective and simple manner so that products generally considered a waste, such as scrapped cross-linked polyethylene pipes or unused cross-linked polyethylene discarded in e.g. pipe making processes, can be recycled and used as a starting material for polymer products.

This steel sheet includes a first coated portion in which an intermetallic compound layer and an aluminum coating layer are provided on a surface of a base steel sheet in order from the base steel sheet side, a first exposed portion in which the base steel sheet is exposed, and a second coated portion in which the intermetallic compound layer and the aluminum coating layer are provided on the surface of the base steel sheet in order from the base steel sheet side, in which in a first direction which is perpendicular to a thickness direction of the steel sheet and is directed from the first coated portion to one end edge of the steel sheet, the first coated portion, the first exposed portion, the second coated portion, and the end edge of the steel sheet are disposed in this order on one surface of the base steel sheet, at least the first coated portion, the first exposed portion, and the end edge of the steel sheet are disposed in this order on the other surface of the base steel sheet in the first direction, and when viewing a cross section parallel to each of the first direction and the thickness direction of the steel sheet, the second coated portion is provided in a lower region which is located on the surface of the base steel sheet and on an inner side of the base steel sheet in the thickness direction of the steel sheet from a virtual line extending in the first direction from a boundary between the first exposed portion and the second coated portion.

Tubular structures, systems, and methods are generally directed to support structures having structural properties similar to thick-walled structures while being formed using materials having thickness amendable to rolling and welding and, thus, useful for rapid and cost-effective fabrication.

Tubular structures, systems, and methods are generally directed to support structures having structural properties similar to thick-walled structures while being formed using materials having thickness amendable to rolling and welding and, thus, useful for rapid and cost-effective fabrication.

A method for manufacturing an electric resistance welded steel pipe having an identifiable seam portion. The method includes electric resistance welding a steel pipe, cutting an inner surface bead and an outer surface bead of the steel pipe in such a manner so as to cut: (i) a whole the outer surface bead and a part of the inner surface bead to leave an uncut portion in the inner surface bead, or (ii) a whole of the inner surface bead and a part of the outer surface bead to leave an uncut portion in the outer surface bead, coating the steel pipe with zinc phosphate, and cold drawing the steel pipe using a plug and a die to make the seam portion of the steel pipe identifiable.

An intelligent module pipeline, an intelligent module helical pipeline winding machine and a winding method thereof. In the cross section of the pipeline, a plurality of intelligent modules (1) are clamped and helically wound end to end to form a circular pipeline; each of the intelligent module units is an arch-shaped module which is formed by injection molding or compression molding; the each intelligent module unit is provided a reinforcing rib structure inside, a fixing device for fixing and clamping from left to right on the side surfaces, and a clamping device for fixing and clamping end to end at the edges. An arc-shaped chute rail is provided on the front surface of a working panel of the winding machine; the arc-shaped chute rail is provided with at least one pair of feed rollers (107), and is further provided with a locking device (108) and a parallel twisting device (106); the same intelligent module units are arranged end to end on the arc-shaped chute rail, and then are locked by means of the locking device, to form a semicircular pipe diameter by means of the feed rollers; then the parallel twisting device twists the semicircular pipe diameter in parallel to change the winding rail; and the intelligent module units are wound in a staggered arrangement to form helical winding pipelines.

A non-metallic cabling continuous oil pipe, relating to the technical field of oil mining in oil fields, is disclosed. Said oil pipe includes an inner liner tube, the inner liner tube which is used to form a passageway for medium transportation. An outer wall of the inner liner tube is provided with a cable embedded layer and a protection sleeve in sequence, the cable embedded layer including cables and a plurality of reinforcement belts. The reinforcement belts are used to resist torsional deformation and to bear an axial tension. The protection sleeve is used to prevent the cables from being worn.