Abstract: A plug which does not cause an adverse effect such as failure of a member constituting the plug when a wellbore is plugged. The downhole plug (10) includes a mandrel (1) having a hollow structure, a sealing member (2) attached to an outer circumferential surface of the mandrel (1) and being deformable by exerted pressure, and a socket (3) attached, adjacent to the sealing member (2), onto the outer circumferential surface of the mandrel (1), downstream of where the pressure is exerted on the sealing member (2). An inner circumferential edge (31a) of the socket (3) which comes in contact with the mandrel (1) protrudes toward the sealing member (2).

Abstract: A plug which does not cause an adverse effect such as failure of a member constituting the plug when a wellbore is plugged. A downhole plug (10) includes a mandrel (1) having a hollow structure, an annular sealing member (2) attached to an outer circumferential surface of the mandrel (1) and being deformable by exerted pressure, and an annular socket (3) attached, adjacent to the annular sealing member (2), onto the outer circumferential surface of the mandrel (1), downstream of where a pressure is exerted on the sealing member (2). The annular socket (3) is configured to include a socket-inner portion (31) which comes into contact with the outer circumferential surface of the mandrel (1), and a socket-outer portion (32) in an annular shape having an inner diameter equivalent to or larger than that of the socket-inner portion (31) and movably attached to the socket-inner portion (31). The socket-outer portion (32) includes a face facing the sealing member (2).

Abstract: A plug which does not cause an adverse effect such as failure of a member constituting the plug when a wellbore is plugged. A downhole plug (10) includes a mandrel (1) having a hollow structure, an annular sealing member (2) attached to an outer circumferential surface of the mandrel (1) and being deformable by exerted pressure, and an annular socket (3) attached, adjacent to the annular sealing member (2), onto the outer circumferential surface of the mandrel (1), downstream of where a pressure is exerted on the sealing member (2). The annular socket (3) is configured to include a socket-inner portion (31) which comes into contact with the outer circumferential surface of the mandrel (1), and a socket-outer portion (32) in an annular shape having an inner diameter equivalent to or larger than that of the socket-inner portion (31) and movably attached to the socket-inner portion (31). The socket-outer portion (32) includes a face facing the sealing member (2).

Abstract: A plug which does not cause an adverse effect such as failure of a member constituting the plug when a wellbore is plugged. A downhole plug (10) includes a mandrel (1) having a hollow structure, an annular sealing member (2) attached to an outer circumferential surface of the mandrel (1) and being deformable by exerted pressure, and an annular socket (3) attached, adjacent to the annular sealing member (2), onto the outer circumferential surface of the mandrel (1), downstream of where a pressure is exerted on the sealing member (2). The annular socket (3) is configured to include a socket-inner portion (31) which comes into contact with the outer circumferential surface of the mandrel (1), and a socket-outer portion (32) in an annular shape having an inner diameter equivalent to or larger than that of the socket-inner portion (31) and movably attached to the socket-inner portion (31). The socket-outer portion (32) includes a face facing the sealing member (2).

Abstract: A plug which does not cause an adverse effect such as failure of a member constituting the plug when a wellbore is plugged. The downhole plug (10) includes a mandrel (1) having a hollow structure, a sealing member (2) attached to an outer circumferential surface of the mandrel (1) and being deformable by exerted pressure, and a socket (3) attached, adjacent to the sealing member (2), onto the outer circumferential surface of the mandrel (1), downstream of where the pressure is exerted on the sealing member (2).

Abstract: To provide a temperature measuring apparatus making it possible to automatically calculate a correction multiplier by assuming the data measured by a contact-type thermometer as a true value and always accurately measure temperature by the noncontact method in accordance with the correction multiplier. The temperature measuring apparatus comprises noncontact- and contact-type thermometers for measuring the temperature of a temperature measurement object, arithmetic means for calculating a correction multiplier for correcting an error of data measured by the noncontact-type thermometer in accordance with the data measured by the noncontact-type thermometer and a value measured by the contact-type thermometer and moreover calculating a correction value by correcting the data measured by the noncontact-type thermometer in accordance with the correction multiplier, and display means for displaying the measured value and the correction value.