| 摘要 |
<p>PROBLEM TO BE SOLVED: To obtain a pipe for inserting optical fibers which is prevented from collapse by side pressure, and has excellent feedability of optical fiber unit, by specifying the modulus of elasticity in bending of the products obtd. by molding a high-density polyethylene(HDPE) to a specific range. SOLUTION: The pipe for inserting optical fibers for inserting the optical fiber unit by compressed air is constituted by specifying the modulus of elasticity in bending of the products obtd. by molding from the HDPE to 9,000 to 17,000kg/cm<2> . If the modulus of elasticity in bending is below 9,000kg/cm<2> , the distortion quantity of the pipe exceeds 1.5mm when the side pressure of about 1.5kg/mm<2> is exerted thereon. The impairment of the feedability of the optical fiber unit is then resulted. On the other hand, if the modulus of elasticity in bending of the pipe for inserting optical fiber exceeds 1,700kg/cm<2> , the rigidity of the pipe is too high that the pipe is hardly bendable and the intertwining of the pipe is difficult. Then, the modulus of elasticity in bending of the resulted pipe for inserting the optical fibers is specified to 9,000 to 17,000kg/cm<2> .</p> |
