A
system for measuring
diameter (inner and / or outer) of a tubular, the
system in at least certain aspects including at least one
linear distance measuring device with respect to which a tubular to be measured is movable, the at least one
linear distance measuring device including a
detector for detecting a surface of the tubular, the
detector movably mounted to
mount apparatus, the
detector movable longitudinally along the surface of the tubular and movable axially in response to variation in
diameter of the tubular, a rotatable head rotatable with respect to the tubular either outside of it or within it, the
mount apparatus secured to the rotatable head, at least one
signal production apparatus secured to the
mount apparatus or head, and in communication with the
linear distance measuring device, the at least one
signal production apparatus for producing a
signal indicative of distance between said detector and a known point, and transmitting apparatus for transmitting said signals to
processing equipment for determining
diameter of the tubular; and in certain aspects the linear distance measuring device is a
laser device, electronic
measurement device, acoustic
measurement device,
infrared measurement device, or
linear variable differential transformer device.