Threaded bolt having measurement planes for use in ultrasonic length measurements

Threaded bolt, for use in ultrasonic measurement for determining the tension in the threaded bolt after it has been used in a connection, said bolt being formed as a unitary single unitary piece of material piece having a proximal head end and a distal insertion end extended about a shank having a substantially cylindrical body and a longitudinal axis,

• the proximal head end and the distal insertion end are each provided with only a single, planar surface which is perpendicular to the longitudinal axis wherein the planer surfaces from radial measurement planes which are exposed in opposite axial directions, the radial measurement plane at the insertion end being formed by a freely exposed, flat bottom of a recess at the distal insertion end,
• wherein the recess is bounded by a first circumferential plane or surface which at a point of change transitions into a second circumferential plane or surface of the distal insertion end at an outermost portion of the distal insertion end, said outermost portion of the distal insertion end being formed by a circular line in a plane perpendicular to the longitudinal axis, and
• wherein the proximal head end is structured and arranged to detachably receive a sensor for measuring a distance between the measurement planes, wherein the proximal head end has an outermost proximal end plane oriented perpendicular to the longitudinal axis, wherein the measurement plane at the proximal head end is located on and formed by the outermost proximal end plane.

Threaded bolt having a proximal head end and a distal insertion end, said bolt being formed as a single unitary piece of material and having a longitudinal axis extending between both said ends,

• wherein the head end and the insertion end have each been provided with only a single, freely planer surface which is perpendicular to the longitudinal axis, wherein the planer surfaces from radial measurement planes which are exposed in opposite axial directions for use in ultrasonic length measurement for determining the tension in the threaded bolt after it has been placed in a connection,
• wherein the measurement plane at the insertion end has a flat bottom of a recess at the insertion end, wherein the recess is bounded by a circumferential wall, which seen in cross-section at the outermost distal end of the bolt changes direction at a substantially V-shaped portion into a flank of the insertion end,
• wherein the proximal head end has an outermost proximal end plane, wherein the measurement plane at the proximal head end is located on the outermost proximal end plane, wherein both measurement planes are perpendicular to the longitudinal axis, and
• wherein said proximal head end is adapted to removably receive a sensor for measuring a distance between the measurement planes.