Sumitomo Metal Industries, Inc.

Vallourec & Mannesmann Oil & Gas France

Nippon Steel Sumitomo Metal Corporation

Ikuji Hoshino

Masaki Yamano

Shigeo Nagasaku

Keiichi Nakamura

Makoto Sakamoto

Kenta Sakai

Jun Masubuchi

The present invention provides a method which allows simply, easily and accurately evaluating the fastening state of shoulder parts of a threaded joint for use as a joint of pipes or tubes, such as OCTG, during fastening or after fastening. The fastening state evaluation method for a threaded jointof pipes or tubes according to the present invention is characterized in that it transmits ultrasonic surface waves from the internal surface of either one of the pinand the boxtoward the internal surface of the other one of the pinand the boxthrough the shoulder partsof the pinand the box, and on the basis of the transmitted wave intensity or the reflected wave intensity thereof, determines whether or not the fastening state of the threaded jointis satisfactory.

Method of evaluating fastening state of threaded joint of pipes or tubes, method for fastening threaded joint of pipes or tubes, and apparatus for evaluating fastening state of threaded joint of pipes or tubes

There is provided a method capable of evaluating a fastening state of a threaded joint that is used as a joint of pipes or tubes such as OCTG with a high degree of accuracy even after being fastened and a method for fastening a threaded joint of pipes or tubes using the evaluating method. The present invention provides a method for evaluating a fastening state of a threaded joint of pipes or tubes including a pin having an external thread part, a metal seal part, and a shoulder part on an outer peripheral surface, and a box having an internal thread part, a metal seal part, and a shoulder part corresponding to each part of the pin on an inner peripheral surface and being fastened with the pin. The evaluating method according to the present invention is characterized by transmitting and receiving an ultrasonic wave to and from a plurality of locations along an axial direction of the threaded joint in at least one of the internal thread part, the metal seal part, and the shoulder part of the box; detecting echo intensities for the plurality of locations; and comparing the echo intensities detected for the plurality of locations to determine whether the fastening state of the threaded joint is good or bad.

Method for evaluating fastening state of threaded joint of pipes or tubes and method for fastening threaded joint of pipes or tubes using the method

An ultrasonic testing method relates to a threaded joint of pipes including a pin having an external thread part, a metal seal part, and a shoulder part on an outer peripheral surface, and a box having an internal thread part, a metal seal part, and a shoulder part with the box and pin being fastened together using a lubricant. The method includes transmitting and receiving ultrasonic waves to and from a plurality of locations along an axial direction of the threaded joint in at least one of the internal thread part, the metal seal part, and the shoulder part of the box; detecting echo intensities and reception times of echoes for the plurality of locations; and detecting an abnormal portion in the threaded joint based on a longitudinal axial directional distribution of the echo intensities and longitudinal axial directional distribution of reception times of the echoes.

Ultrasonic testing method of threaded joint of pipes or tubes

Growing community of inventors

Osaka, Japan

Ikuji Hoshino