IL33183A - Method of manufacturing tubes - Google Patents

Description

33 Method of manufacturing tubes MARCEL AHLQVIST 31461 A 2 Invention r elates to tubes and methods of manufacturing According to one aspect of the present there is provided method of manufacturing a ing in first producing a wall element the form of a tube part and a fastening part manufactured all in one which fastening part has a portion with a contour which corresponds to the contour of at least one portion of the tube and then winding the wall element helically with the tube part turn in the fastening part of an adjacent turn and making an adhesive joint between adjacent turns of the helically wound tube in which during the production of the wall foamable plastics material is introduced into the tube part of the wall which plastics material is allowed to stiffen after the wall element helically According to a further aspect of the present there is provided a tube manufactured in ance with the method as defined in the preceding For a better understanding of the invention and to sho how the same may be carried into reference will now be made to the accompanying in 1 is a perspective view of a wall 2 is a transverse section of a part of a 3 is a longitudinal section of a part of a and 4 shows in principle a part of a machine manufacturing the wall he wall element shown in 1 takes the form of a tube part 10 and a fastening part 11 all in one This fastening part 11 has a portion with an inner contour which corresponds to the outer contour of one portion of the tube part From the it will be seen that the left lower portion of the tube part 10 has an outer contour which corresponds to the inner contour of the fastening part The tube is manufactured in the following Whilst making the wall element a foamable thermoplastic or thermosetting or a mixture of components which react in situ to form polyurethane is introduced into the tube part 10 of the wall element bein After the wall element has been wound helically with the tube part 10 of one turn inserted in the part 11 of an adjacent the resin is accompanied by curing as the case may or of components is caused react to produce the polyurethane An adhesive is inserted between the tube part 10 and the fastening part 11 so that a helical joint established consisting of the tube part the adhesive and the fastening part Excluding the a helical between the tube part 10 and the fastening part 11 may be obtained by by bringing the helically wound wall element to pass between two heating 4 B introducing the foamable material in the tube part 10 of the wall element immediately after the wall element has left the extruder arranged for forming the wall it is possible to carry through the facture of the tube part 10 in a single In the machine shown in the wall element is manufactured by kneading plastics material and porting the material by a screw the material then being pressed through an ectruder head 41 so that an element with a tube part 10 is see for example The plastics material fed through a feeding tube which is brought through the extruder head 41 and thus ends beyond that side of the head which is remote from the screw As indicated the foamed plastics material can be formed in the tube part 10 in a of different A foamable thermosetting such as a phenolic can be introduced into the tube part 10 and subsequently simultaneously cured and a plastic for containing a ing agent can be introduced and expanded to form a foam by the wall element after the wall element has been helically wound and thus vapou the blowing a mixture of reactants can be introduced into the tube part 10 which react in situ to produce a polyurethane foam which can be either thermoplastic or thermosetting and can optionally have an integral In the case of a thermosetting the helical winding must take place before the reviousl foamed foamed in insufficientOCRQuality

Claims (6)

1. A method of manufacturing a tube, consisting in first producing a wall elemen in the form of a tube part and a fastening part manufactured all in one piece, which fastening part has a portion with a contour which corresponds to the contour of at least one portion of the tube part, and then winding the wall element helically with the tube part of one turn inserted in the fastening part of an adjacent turn and making an adhesive joint between adjacent turns of the helically wound tube; in which method, during the production of the wall element, foamable plastics material is introduced into the tube part of the' wall element, which plastics material is allowed to stiffen (solidify) after the wall element is helically wound.

2. A method as claimed in Claim 1, wherein the foamable plastics material is introduced in the tube portion of the wall element immediately after the wall element has left an extruder head forming the wall element.

3* A method as claimed in Clai 1 or 2, wherein a foamable thermosetting resin is introduced in the tube part of the wall element, and wherein immediately after this the wall element is helically wound.

4* A method as claimed in Claim 1 or 2, wherein a foamable thermoplast is introduced in the tube part of the wall element, and wherein after the wall element has been helically wound, the wall element is heated to the necessary hardening temperature. - 6 - 33183/2

5. A method of manufacturing a tube substantially as hereinbefore described with reference to the accompanying drawing.

6. A tube, manufactured according to the method of any one of Claims 1 to 5. For the Applicants T-SEES EHA/rb