| 摘要 |
<p>PROBLEM TO BE SOLVED: To obtain a master conduit into which a cable protection sheath is inserted and pipe smoothly and in a short time and whose operability is enhanced sharply, by a method wherein a pipe wall is formed in an uneven wave shape and a plurality of stages of partition walls which are connected up and down by vertical walls are fitted internally into its internal space in a nearly horizontal posture. SOLUTION: In a pipe body, small-diameter walls 2 in which the shape of every pipe wall is made cross-sectionally circular and large-diameter walls 3 which are square-shaped by rounding respective corners of their cross-sectional shapes and every side 3a of which is larger than the small-diameter walls 2 are arranged alternately in the axial direction of the pipe body so as to be formed integrally. Then, partition walls (d) which are composed of three upper, middle and lower transversely sheetlike partition walls and of vertical walls (w) which connect their central parts up and down are inserted into the internal 4 of the pipe body. At this time, the respective partition walls (d) and upper sides and lower sides of the large-diameter walls 3 are made parallel. When the pipe body is buried underground, it is laid in such a way that the upper sides and the lower sides of the large-diameter walls 3 become a horizontal state, i.e., the partition walls (d) become a horizontal state. Then, cable protective sheaths (s) are inserted into a master conduit P in such a way that their number can be increased up to the number capable of being inserted on one partition wall (d) in a row transversely.</p> |
