Abstract: A process for the coating of metal tubes by the application of polyethylene to the preheated tubes, a polyethylene with a melt index of over 1 g/10 minutes being applied first to the pre-heated metal tube and a polyethylene with a low melt index being applied thereupon, the process comprising a first step of applying a polyethylene with a melt index of 1.2 to 70 g/10 minutes (190.degree. C./2.16 kg) to the metal tube which has been pre-heated to a temperature of at least 200.degree. C., a second step in which the coating is cooled to a temperature of about 110.degree. to 170.degree. C. and a third step of applying a self-supporting film of polyethylene with a melt index of 0.1 to 7 g/10 minutes at this temperature so that the total coating has a minimum layer thickness of 1.5 to 4 mm and a coated article coated according to said process.

Abstract: A spacer is coiled about a drawn, seamless copper tube, and a metal foil or metallized paper ribbon is folded around the coiled spacer. A blend for foaming is injected into the unoccupied space between the folded foil or ribbon and the inner tube, to generate a cyanurate-modified polyurethane foam network in which phosphorous or halogen molecules are embedded by chemical bond. A flame-resistant ribbon is folded about the metal tube. The resulting product and further details of the process are described.

Abstract: A composite flexible tube is disclosed. The central portion of the core of the tube is formed of a plurality of hollow elements dipsosed concentrically about the longitudinal axis of the tube.

Abstract: A flue stack maintenance system particularly for those flues through which grease laden air passes such as for example exist in commercial restaurant kitchens and the like (FIG. 1), which utilizes an expandible, elongated metal foil liner bag which forms a closed interior system except for an air inlet conduit provided for the application into the interior of the bag an air pressure greater than the ambient to balloon out the bag into facing engagement with the interior of the flue stack (FIG. 3B). After the bag is ballooned out, the upper and lower ends are opened and folded over and around the ends of the flue for attaching the foil liner to the flue (FIG. 3C).

Abstract: A helical circular wave guide which reduces loss around curves. It includes contiguous turns of copper wire coated with a thermoplastic material, said helical turns being surrounded by a first tube made of aluminium in contact with the helix and by a second tube made of steel held centered in relation to said first tube by supports made of plastic material.

Abstract: A flexible hose comprising a lining layer of substantially impermeable material, a reinforcement structure comprising at least one balanced pair of helically extending reinforcement members embedded in elastomeric material to withstand internal pressure and axial tensile loadings, and radially inwards of at least the reinforcement structure a crush resisting armouring layer comprising at least two helical reinforcing elements nested together and shaped such that contacting surfaces of the elements between the successive turns of the helices are of a substantially frusto-conical shape.

Abstract: Vibration absorbing connector for use in high pressure fluid piping systems such as the refrigerant lines in an automotive air conditioning system incorporates a thin bellows member whose ends are restrained against axial movement by a restraining means such as a plurality of axially extending flexible cables or a braided metal sleeve which surrounds the bellows member. A molded-in-place elastomeric layer fills in the external bellows corrugations to prevent their deformation under load and encapsulates the restraining means. The design permits a 3 inch long bellows having a 0.005" wall thickness to perform as well as a 7 inch long bellows having a 0.020" wall which has a conventional configuration under internal fluid pressures that would collapse the thin wall bellows corrugations in the absence of the elastomeric layer.

Abstract: A metal, convoluted tube with integral, extending end connectors, with the inwardly extending convolutes of the tube exterior filled with and bonded to a non-porous elastomer, and the elastomer extends a substantial distance onto the extending end connectors and outwardly beyond the metal convolutes.

Abstract: A composition especially useful as a primer coating having improved hot line adhesion and cathodic disbonding resistance comprises a solution of chlorinated rubber and aromatic petroleum pitch in a solvent.

Abstract: A coated hollow metal tube being processable by bending, pressing or punching without the cracking or peeling of the coating; said tube comprising a hollow metal tube and a coating, in tight adhesion thereto, of a thermoplastic crystalline copolyester having a second order transition point of at least 50.degree. C and a degree of crystallization of not more than 15%. A coated hollow metal tube processed by bending, pressing or punching is produced by coating the hollow metal tube with the thermoplastic crystalline copolyester, cooling the coating, and then subjecting the coated hollow metal tube to bending, pressing or punching. The product has utility in furniture, conduits for municipal gas and water supplying facilities, automobile parts, and other indoor or outdoor articles and building materials.

Abstract: A waveguide element is formed of a body of plastics resin, such as, acrylonitrile-butadiene-styrene resin, having a tubular portion open at its opposite ends and flanges directed outwardly at such ends, and a conductive layer, for example, of an electroless plated metal such as tin-cobalt alloy, covering the inner surface of the tubular portion and the surfaces of the flanges which face axially in the directions that the respective ends open. For ease of molding or forming the body of plastics resin, such body may be comprised of a pair of complementary parts divided at a plane extending longitudinally in respect to the tubular portion, with such parts having mating flanges directed outwardly along their longitudinal edges and with the conductive layer also covering the confronting surfaces of the mating flanges.

Abstract: A heat recoverable article for shielding junctions in cables or conduits comprising a corrugated sheath in part capable of radial deformation disposed within a member of heat-recoverable material part of the sheath having transverse corrugations that resist deformation. A sheath made of conductive material may function to protect the junction from radio frequency interference. The ends of the member may be provided with adhesive to render the junction impermeable to water, gases, etc.

Abstract: Combined strengthening and corrosion protection of a ferrous metal pipeline is obtained by means of a wrap of ferrous metal strip, the strip being coated with a less noble metal, such as zinc or aluminum or a zinc alloy or an aluminum alloy, and the strip being under sufficient tension to strengthen and reinforce the pipe or to arrest fracture propagation. The less noble metal coating of the strip is electrically connected to the pipe to provide cathodic protection for the pipe. A coating of electrically insulating material may be interposed between the pipe and the wrap. An external power source may be utilized for primary cathodic protection in which case the coated strip is relied upon as a secondary or back-up system.