Ahead non widening joint structure of the placing tube which is used for receiving construction method

摘要

Topic When digging thinning the terminal tube which is withdrawn, ahead non widening receiving construction method it decreases cost.Solutions The head tube 1 where each major diameter is the same diameter and intermediate tube it is the structure which joints 2 and terminal tube 3 mutually with the screw. The screw of the rear end of head tube 1 makes male screw 1a, as for the screw of the toe of switch of intermediate tube 2 male screw 1a and makes the female screw 2a which spiral shellfish conjunction is produced, the screw of the rear end of intermediate tube 2 makes male screw 2b, as for the screw of the toe of switch of terminal tube 3 male screw 2b and makes the female screw 3a which spiral shellfish conjunction is produced, also the screw of the rear end of terminal tube 3 makes female screw 3b same as the toe of switch. As for the screw of the ended cap it makes the male screw which spiral shellfish conjunction is produced in female screw 3b of terminal tube 3. By the fact that the screw of front and back of terminal tube 3 is designated as the female screw, be able to form the wall thickness which is necessary in order to form the male screw and the female screw respectively in thickness of approximately 2/3, when digging reducing the material of the terminal tube 3 which is withdrawn, ahead non widening receiving construction method it reaches the point where it can decrease cost. Choice figure Drawing 1