Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
  • F16L59/00—Thermal insulation in general
  • F16L59/04—Arrangements using dry fillers, e.g. using slag wool which is added to the object to be insulated by pouring, spreading, spraying or the like
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
  • F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
  • F16L59/00—Thermal insulation in general
  • F16L59/14—Arrangements for the insulation of pipes or pipe systems

Definitions

• the present invention relates to a method for isolating a spirally wound pipe of a thermoplast hole profile, which is joined together by extruder welding or gluing.
• An advantage of a spirally wound pipe with a hole profile is that a desired ring stiffness is achieved with a con ⁇ siderably lower material thickness than for a single- walled pipe.
• isolation of the pipe ⁇ lines is required.
• also pipelines of such spirally wound pipes are furnished with an outer isolation layer, which may be encased by an outer protective sheath.
• Such an arrange ⁇ ment is relatively curbersome and significantly increases the material consumption.
• the purpose of the present invention is to eliminate this problem, which is achieved by means of an arrangement characterized in that
• the spirally wound pipe is maintained in a horizontal position and rotated around its longitudinal axis, until such a row of holes is located uppermost in the pipe,
• a foaming lance is led into said or another row of holes up to the closed side wall, after which a foaming isolating mass is dosed by turns into each segment of the spirally wound pipe as the lance is stepwise drawn back out of the hole,
• Fig. 1 shows an end of a spirally wound pipe, in which holes are arranged for feeding the isolating mass according to the invention
• Fig. 2 shows a section along line A-A of Fig. 1, in which a foaming lance is introduced into a row of boring holes lowermost in the spirally wound pipe.
• the isolation of the spirally wound pipe of a thermoplastic hole profile 1 of a mainly rectangular cross-section is performed as follows:
• At least one radially directed hole 3, 3a is made so that a row of holes 3, 3a located in line with each other is formed through the entire pipe up to said end surface. Both end surfaces of the hole profile are chamfered and closed in a suitable manner in this or other previous step.
• a foaming lance 4 is introduced either into said row of holes 3a or another row of holes 3, which is located on a lower level, to a hollow space, which is limited by the closed side wall 2a.
• the foaming isolating mass 5 is dosed through the foaming lance 4 by turns into each segment of the spirally wound pipe as the foaming lance 4 is stepwise drawn back out of the holes 3, 3a, until all segments of the spirally wound pipe are fed with a dosed amount of the isolating mass.
• the boring holes 3, 3a may either be made subsequently as a new turn of the hole profile has coincided with the spirally wound pipe or after the entire pipe is joined together.
• the equipment In the first case, the equipment must be arranged to sense when the pipe, which during the joining-together process is continuosly in a slow rotation, reaches a position, in which a hole 3, 3a should be made.
• This may be arranged in such a way that the spindle, around which the hole profile is wound up in connection with the manufacturing of the spirally wound pipe, has stop or sensing means, which give a starting impulse to a boring or milling device each time the pipe comes in the correct working position.
• one or two rows of holes 3, 3a may be received.
• an isolating mass of a low viscosity and a relatively long foaming time as well as good dosing properties only one row of boring holes 3a is needed, since then the liquid isolating mass has time to run down into the bottom section of the pipe before the foaming starts.
• two rows of boring holes 3, 3a are preferable, which are totally diagonally positioned in relation to each other, whereby the isolating mass does not have to be transferred before the foaming begins, which possibilitates the utilization of an isolatating mass with a very rapid foaming.
• a bowing distance of ca. 90° between the two rows of boring holes 3, 3a may be preferable, especially if the isolating mass is lightly flowing, before a time after the foaming has started, whereby the leakage of the isolating mass through the below boring hole 3 on the end surface of the pipe is avoided.
• small evacuation holes 6 for air may be received in the radially directed side walls 2 of the profile. These evacuation holes 6 are preferably made uniformly distributed along the centre line of the radially directed side walls 2.
• a suitable isolating mass is a polyurethane foam, which has reached a very wide use as an isolating material around the world.
• the foaming may be either performed directly on the product after the manufacturing of the spirally wound pipe itself or on site in connection with the installation of the pipelines.

Landscapes

• Engineering & Computer Science (AREA)
• General Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Thermal Insulation (AREA)
• Shaping Of Tube Ends By Bending Or Straightening (AREA)
• Extrusion Moulding Of Plastics Or The Like (AREA)
• Manufacture Of Motors, Generators (AREA)
• Molding Of Porous Articles (AREA)

Priority Applications (3)

Applications Claiming Priority (2)

Publications (1)

Family

ID=8532423

Family Applications (1)

Country Status (8)

Citations (5)

• 1991
  • 1991-04-30 FI FI912100A patent/FI94982C/sv not_active IP Right Cessation
• 1992
  • 1992-04-29 AT AT92909233T patent/ATE139318T1/de not_active IP Right Cessation
  • 1992-04-29 ES ES92909233T patent/ES2090634T3/es not_active Expired - Lifetime
  • 1992-04-29 EP EP92909233A patent/EP0587584B1/en not_active Expired - Lifetime
  • 1992-04-29 DK DK92909233.6T patent/DK0587584T3/da active
  • 1992-04-29 WO PCT/FI1992/000129 patent/WO1992019899A1/en active IP Right Grant
  • 1992-04-29 DE DE69211550T patent/DE69211550T2/de not_active Expired - Fee Related
• 1996
  • 1996-09-13 GR GR960402417T patent/GR3021049T3/el unknown

Patent Citations (5)

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