Abstract: A method of rehabilitating underground pipes which comprises the steps of: (a) forming a liner pipe (5) by winding a strip (4) made of a synthetic resin into a helical shape so that the side edges of the convolutions of the wound strip (4) are interengaged with each other; (b) continuously introducing the liner pipe (5) into an underground pipe (1) while the liner pipe (5) is being advanced inside the underground pipe (1); inserting a slip restraining member in the form of a wire rod (6) continuously to the interconnected edges of the convolutions of the said strip (4), and then removing the said strip (4) when the diameter of said liner pipe (5) is to be increased at the same rate as said strip (4) for forming said helical liner pipe (5) is conveyed.

Abstract: This invention relates to a method of drilling apertures for branch lines (A) blocked by renovation lining of a main pipeline (B) which comprises setting a water plug (1) in the opening of each branch line (A) prior to lining, said water plug (1) carrying a position marker (14) comprising an antenna coil and a resonator adapted to be excited by a driving signal and, after stoppage of the driving signal, release a resonance signal remaining in the resonator from the antenna coil and said position marker being situated in a position which, upon setting of the water plug (1) in position, is substantially concentric with the axis of the branch line (A), causing an antenna assembly for detecting the resonance signal to travel within the main pipeline (B) to detect the position of the marker (14) and driving a drilling means (24) using the thus-detected marker position as a target from within the main pipeline.

Abstract: A soil amendment matter is provided which is effective for preventing soils from suffering from injuries due to continuous cropping. This matter is obtained by adding a soil to a medium containing 2-oxo-4-methyl-6-ureidohexahydropyrimidine (OMPU) as nutrient and subjecting the mixture to an aerobic cultivation treatment. Further the matter can contain OMUP as an additional effective component. These matters can be adsorbed on an adsorbent and used.

Abstract: A method for continuously producing a reinforced plastic pipe includes helically winding an endless belt on a rotating mandrel, continuously winding a molding material impregnated with a thermosetting resin on the endless belt, continuously moving the molding material toward the tip of the mandrel together with the endless belt by the rotation of the mandrel, passing the moving molding material through a curing zone to cure the thermosetting resin, and then removing the molding material from the endless belt at the tip portion of the mandrel. Prior to the introduction of the molding material into the curing zone, a split ring mold having an inside surface of a desired shape is mounted around the molding material so as to clamp the molding material tightly, thereby to convert the shape of the outside surface of the molding material into one corresponding to the shape of the inside surface of the split ring mold.