Claims
- 1. Apparatus for the underground irrigation or watering of soil, comprising:
- a flexible tubing made of a synthetic polymer, having an outside wall surrounding an internal structure, said internal structure being made of a non-expanded porous materials, said flexible tubing being obtained through extrusion of a homogeneous mixture of at least two components, one component being a meltable polymer and the other component being a liquid inert in relation to the polymer, both components forming a binary system displaying in liquid aggregate state a range of complete miscibility and a range with a miscibility gap depending upon varying parameters of temperature and concentration.
- 2. The apparatus according to claim 1 wherein said flexible tubing of synthetic polymer with a non-expanded porous inside structure has an inside wall surface with open pores and an outer wall surface with openings, the degree of openings of which, calculated as a fraction of open area, at least 20% in relation to the open pores of the inside wall surface.
- 3. The apparatus according to claim 1 wherein said tubes which display open pores in the outer wall surface for the most part of a pore diameter of less than about 4 .mu.m.
- 4. The apparatus according to claim 3 wherein said pore diameter is less than about 3 .mu.m.
- 5. The apparatus according to claim 1, wherein said tubes have a pore cavity volume of from about 50-90%.
- 6. The apparatus according to claim 5 wherein said pore cavity volume is from about 70-80%.
- 7. The apparatus according to claim 1, wherein said tubes are made of polypropylene.
- 8. The apparatus according to claim 7 wherein said tubes are of glass fiber-reinforced polypropylene.
- 9. The apparatus according to claim 1 wherein said tubes have a wall thickness of about 0.5 to 2.5 mm and an outer diameter of about 2.5 to 25 mm.
- 10. The apparatus according to claim 9, wherein said wall thickness is from about 1 to 1.5 mm and said outer diameter is from about 7 to 12 mm.
- 11. The apparatus according to claim 1, wherein said tubes are disposed in tubular-shaped sheaths of matted web, which are composed of a plurality of fibers melt-upon from synthetic polymers, crossing over in places and fused together at the places of crossing.
- 12. The apparatus according to claim 11, wherein said sheaths of a matted web have a longitudinal grooved contour.
- 13. The apparatus according to claim 11 wherein said matted web is of polycaprolactam fibers with a diameter of about 0.2 to 1.5 mm.
- 14. The apparatus according to claim 11, further comprising couplings, composed of the same material as the sheaths and which are disposed at intersection of the sheath.
Priority Claims (1)
Number |
Date |
Country |
Kind |
3049558 |
Dec 1980 |
DEX |
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Parent Case Info
This is a continuation of application Ser. No. 638,981, filed Aug. 8, 1984, abandoned, which in turn is a continuation of Ser. No. 335,394, filed Dec. 29, 1981, abandoned.
US Referenced Citations (16)
Continuations (2)
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Number |
Date |
Country |
Parent |
638981 |
Aug 1984 |
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Parent |
335394 |
Dec 1981 |
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