Patent ID: 8804104

Claim:
An apparatus for measuring thread features of a threaded pipe or tube end, comprising: an optical sensor that measures a first thread feature, which does not relate to measurement of a thread flank surface, by detecting light that reaches from a light source located on the opposite side of the pipe or tube axis and runs substantially in parallel to the thread grooves; a contact sensor that measures a second thread feature, which relates to measurement of the thread flank surface, by contacting a contact probe onto the thread flank surface and detecting the space coordinates of the contact probe at a time of contact; and a processor that calculates thread features from the combination of the first thread feature and the second thread feature, wherein the contact sensor measures a profile of the thread flank surface by contacting the contact probe onto measuring points of the thread flank surface, the measuring points being spaced each other at different distances to the pipe or tube axis, wherein the processor combines a profile of an area other than the thread flank surface measured by the optical sensor with the profile of the thread flank surface measured by the contact sensor to calculate a thread profile, and wherein the thread flank surface includes a hooked frank surface having a hook shape.