| 摘要 |
A boring plug provided with a mandrel and at least one diametrically expandable annular rubber member and at least one slip placed on the outer circumferential surface of said mandrel; wherein, in the boring plug formed from a degradable rubber material: (i) the mandrel is formed from a degradable material; and (ii) the at least one diametrically expandable annular rubber member has a rate of decrease in 50% strain compressive stress of 5% or more after being immersed in water having a temperature of 150°C for 24 hours, with respect to the compressive stress before immersion, and/or a decrease in mass of 5-100% after being immersed in water having a temperature of 150°C for 72 hours, with respect to the mass before immersion. A method for boring in which the boring plug is used to fill a borehole, after which part or all of the plug decomposes. |
