Oy Kwh Pipe Ab

Oy Wiik & Hoglund Ab

Uponor Infra Oy

Gunnar Blomqvist

Stefan Slotte

Anders Andtbacka

Jarl-Erik Jofs

Jonas Holmlund

Hans Hede

Henry Södergård

Ted Taylor

Ari Sillanpää

Kristian Sundqvist

Ari Sillanpaa

Henry Sodergard

A method of producing a plate-like construction having a double-wall structure and its use. According to the present invention, several elongated profiles which have essentially straight central axes are arranged against each other in such a way that adjacent hollow profiles abut each other and together form, in general terms, a flat stack having two opposite sides. The hollow profiles are welded together in order to join them with welded seams, in which case the welding is essentially carried out simultaneously from both sides of the stack. Besides good flexural strength and the opportunity to recycle, thermoplastic plates which are produced by means of the present method exhibit resistance to corrosion, decay and mould.

Method of producing a plate-like construction with a double-wall structure

The invention relates to a method and a device for cooling an extruded thermoplastics pipe () by directing a gaseous cooling medium tangentially towards the inner surface of the thermoplastics pipe () along its whole periphery, whereby the interior of the thermoplastics pipe () is divided by means of a protecting pipe () into an outer ring-shaped flow channel () for the cooling medium along the inner surface of the thermoplastics pipe (), and a central return channel () through which a part of the cooling medium is intended to be sucked back influenced by the flow of cooling medium in the outer ring-shaped flow channel (), and to be redirected towards the inner surface of the thermoplastics pipe (). The invention is characterized in that the cooling medium is air, and that there is a cooling equipment () mounted in the return channel (), whereby temperature and flow rate at least of the cooling water led to the cooling equipment () and possibly also of the cooling air which is fed into the thermoplastics pipe () are adjusted and controlled based on dimension and extrusion rate of the thermoplastics pipe () being manufactured.

Device for internal cooling of extruded thermoplastics pipes

A method for preparing an end of a thermoplastics tube ( ) is provided, wherein the tube is manufactured by spirally winding and welding together of a hollow profile ( ) having a substantially rectangular cross section. The method includes the following steps: cutting the end of the tube by a planar transversal section; extruding a second hollow profile ( ) having a rectangular cross section and an outer shape essentially similar to Fat of the hollow profile ( ) from which the tube ( ) is manufactured; spirally winding the extruded second hollow profile ( ) around a drum having a diameter corresponding to inner diameter of the tube ( ); cutting a loop ( ) from the second hollow profile ( ) in a length corresponding to circumference of the tube end; joining the ends of the loop ( ) to each other, whereby a ring ( ) is formed having the same inner and outer diameters as the spirally wound tube ( ); placing the ring ( ) against the cut tube end; and welding the ring ( ) to the tube end.

Preparation of an end of a thermoplastics tube manufactured by spirally winding a hollow profile

A method for joining thermoplastic pipes made by spiral winding a hollow profile with mainly rectangular cross section. The method includes: cutting an end of the pipe along an inside of a profile side wall fastened to a nearest preceding wound round of said profile and with a section cutting an outermost end of the profile in a right or obtuse angle, or equal size for all pipe ends to be joined together; closing hole in such cut profile ends, and preparing end surfaces of the pipes along their entire peripheries; positioning two pipes in alignment with each other; inserting a welding ring, having dimensions matching with the inner and outer diameters of the pipes, between the two pipes; the welding ring comprising at least one loop of a resistance wire covered by a thermoplastic sleeve, aligning the two pipes with an inner root support and an outer root support, pressing the pipe ends together against each other; connecting the resistance wire of the welding ring to a current source to heat the thermoplastic materials in the welding ring and in the pipe ends so that the thermoplastic materials melt and form a welding seam, cooling the welding seam; removing the root supports and other accessories from the pipe welded together, and cutting off the connecting wires of the welding ring.

Method for joining spiral wound pipes

Welding method in the manufacture of a spirally wound tube and a welding

Method for joining spirally wound thermoplastic pipes together

Method for manufacturing a joint pipe

Plastic tube formed by spiral winding of hollow section

The invention provides a method of forming composite products of two incompatible plastics or other materials by extruding a first stream of plastic through a die to form a profile and coextruding another stream on the surface thereof which is fusible with the first plastic and is impregnated with foreign matter and causing, by means of high heat, pressure drop or shear stress, a rupture of the layer to form a pattern of irregular cavities and projections to which a coating can be applied which will invade the cavities and surround the projections to bond with the extruded profile.

Method of fabricating composite products

Growing community of inventors

Helsingby, Finland

Gunnar Blomqvist