Abstract: A first thread feature is measured by detecting with an optical sensor 2 light that reaches from a light source 21 located on the opposite side of a pipe axis and runs substantially in parallel to thread grooves A4. A contact probe 31 of a contact sensor 3 is contacted with a thread flank surface A8 to detect the space coordinates of the contact probe 31 at the time of contact, so that a second thread feature is measured. The first and second thread features thus detected are combined with each other by a processor 4, and thread features of the thread provided as a measurement object are thereby calculated.

Abstract: A dimension measuring device 100 in accordance with the present invention includes an end face following mechanism 1 that butts against an end face E of a long material, a dimension measuring mechanism 2 for measuring the dimensions of the long material, and a pushingly moving mechanism 3 for pushingly moving the end face following mechanism toward the end face of the long material. The end face following mechanism includes a plurality of contact sensors for detecting a contact state, and is turnable around two axes intersecting at right angles with each other. The pushingly moving mechanism pushingly moves the end face following mechanism into the state in which the plurality of contact sensors detect that the end face following mechanism butts against the end face of the long material.

Abstract: A first thread feature is measured by detecting with an optical sensor 2 light that reaches from a light source 21 located on the opposite side of a pipe axis and runs substantially in parallel to thread grooves A4. A contact probe 31 of a contact sensor 3 is contacted with a thread flank surface A8 to detect the space coordinates of the contact probe 31 at the time of contact, so that a second thread feature is measured. The first and second thread features thus detected are combined with each other by a processor 4, and thread features of the thread provided as a measurement object are thereby calculated.

Abstract: A dimension measuring device 100 in accordance with the present invention includes an end face following mechanism 1 that butts against an end face E of a long material, a dimension measuring mechanism 2 for measuring the dimensions of the long material, and a pushingly moving mechanism 3 for pushingly moving the end face following mechanism toward the end face of the long material. The end face following mechanism includes a plurality of contact sensors for detecting a contact state, and is turnable around two axes intersecting at right angles with each other. The pushingly moving mechanism pushingly moves the end face following mechanism into the state in which the plurality of contact sensors detect that the end face following mechanism butts against the end face of the long material.

Abstract: A plug member can be mounted to the end of a pipe and removed therefrom by automated operation. A mounting and dismounting device 21 for mounting and dismounting a plug member 11 with respect to an oil country tubular good P. The plug member 11 comprises an outer tube 12 having seal portions 16a and 16b and a circumferential groove 12a, a shuttle 13, a cap 14, and a shuttle biasing spring 15 secured to the cap 14 and the shuttle 13. The mounting and dismounting device 21 comprises a tubular holding body 22, a rod 23 which has a conical end portion 23a and which is disposed so as to move inside the tubular holding body 22, and moving means 24 and 25 which allow the tubular holding body 22 and the rod 23 to independently move. The tubular holding body 22 has ball-receiving holes 22a into which fit balls 26 which engage with the circumferential groove 12a.