GB884564A - Method and apparatus for land irrigation - Google Patents

Abstract

884,564. Soil irrigation. BLASS, L. Feb. 24, 1958 [Feb. 22, 1957], No. 39135/56. Class 33 [Also in Group XXIX] In a method of irrigating land water is passed through a primary tube 3 to which secondary tubes 5 with spaced terminal outlets 6 are attached, the pressure drop between the primary tube 3 and a secondary tube 5 bearing a ratio to the pressure drop across the outlets 6 greater than two. In apparatus therefor the flow resistance to the water between the tube 3 and each secondary tube 5 bears a ratio to the total effective flow resistance of the outlets 6 in the tube 5 acting in parallel greater than two. The ratio may be at least ten, or at least twenty or even fifty. The primary tube 3 (and the tubes 5) may be rigid or of rubber or like flexible material and connectors 4 having a resistive passage may connect the tubes 5 to it. A connector 4 has a flange 7 and a neck 8 which are inserted into a hole in the tube 3 for retention and may have a conical outlet hole 10 with a tube 5 therein, and the resistive passage may offer a tortuous water path. The connector 4 may comprise two parts, one, 12, with a male and the other with a female screw-thread, one of the threads being truncated to form a helical path for the water therebetween. Each outlet hole 6 may be in a groove and may have a cover 16 over it, a drainage channel 17 being thus provided, Fig. 4, from the hole 6 into the open. The cover 16 may be a split ring partially around the tube 5.