| 摘要 |
<p>PROBLEM TO BE SOLVED: To specify the range of frictional force increase of a propulsion pipe and to reduce friction as well. SOLUTION: Couplings are provided between propulsion pipes 12. To these couplings, expansion and shrinkage detecting sensors 20 are fitted making it possible to detect the variations of the relative positions between the propulsion pipes 12 adjoining. To a measuring means 32 the expansion and shrinkage detecting sensors 20 are connected, and along with it a console is connected. In the measuring means 32, distances from propulsion jacks in individual expansion and shrinkage detecting sensors 20 are stored beforehand, and the values of the initial pushing thrusts of the propulsion jacks are taken in from the above-mentioned console with value variations from individual expansion and shrinkage detecting sensors 20 used as trigger signals, and the relation with the distance from the propulsion jack of an expansion and shrinkage detecting sensor 20 whose value varied is displayed. By constituting a measuring apparatus 10 for frictional forces on the peripheries of the propulsion pipes in this way, it becomes possible to specify the range of increase of a peripheral frictional force on each propulsion pipe 12, and it becomes possible to reduce the peripheral frictional force by impregnating a part of the pipe being in the range of increase with lubricant.</p> |
