A thermally stabilized fastener system and method is disclosed. The disclosed system/method integrates a fastener (FAS) incorporating a faster retention head (FRH), fastener retention body (FRB), and fastener retention tip (FRT) to couple a mechanical member stack (MMS) in a thermally stabilized fashion using a fastener retention receiver (FRR). The MMS includes a temperature compensating member (TCM), a first retention member (FRM), and an optional second retention member (SRM). The TCM is constructed using a tailored thermal expansion coefficient (TTC) that permits the TCM to compensate for the thermal expansion characteristics of the FAS, FRM, and SRM such that the force applied by the FRH and FRR portions of the FAS to the MMS is tailored to a specific temperature force profile (TFP) over changes in MMS/FAS temperature. The TCM may be selected with a TTC to achieve a uniform TFP over changes in MMS/FAS temperature.

A weld stud including a shank that has a reduced diameter portion, and a larger diameter portion. A weld base is defined on the reduced diameter portion and a flange is positioned on the larger diameter portion. A bore wall extends axially through a face of the flange and into the larger diameter portion. The bore wall has a threaded portion that has a threaded diameter for receiving a fastener. A base diameter of the weld base is smaller than a larger diameter of the larger diameter portion and substantially equal to, or smaller than the threaded diameter. The threaded portion is axially spaced from the face of the flange by a first unthreaded portion, which defines a first unthreaded diameter that is larger than the threaded diameter. These features limit the loads transmitted to the fastener, thus allowing the weld stud to withstand shock loads to prevent fastener failures.

A weld stud including a shank that has a reduced diameter portion, and a larger diameter portion. A weld base is defined on the reduced diameter portion and a flange is positioned on the larger diameter portion. A bore wall extends axially through a face of the flange and into the larger diameter portion. The bore wall has a threaded portion that has a threaded diameter for receiving a fastener. A base diameter of the weld base is smaller than a larger diameter of the larger diameter portion and substantially equal to, or smaller than the threaded diameter. The threaded portion is axially spaced from the face of the flange by a first unthreaded portion, which defines a first unthreaded diameter that is larger than the threaded diameter. These features limit the loads transmitted to the fastener, thus allowing the weld stud to withstand shock loads to prevent fastener failures.

The invention relates to a monitoring attachment for monitoring a nut (9) of a screw connection for cracking, deformation and/or breakage, wherein the monitoring attachment has a conductor loop which is guided around an outer periphery of the nut (9) and which is interrupted in the event of deformation, cracking and/or breakage of the nut (9). The monitoring attachment is characterised by at least two segments (1, 1, 1, 1) which together enclose the periphery of the nut (9) and are held together frictionally at at least one radial connection point, wherein the conductor loop is guided over contacts at the connection point.

A component, provided with a thread has increased play in the axial direction in comparison with a standard thread, which allows nuts to be screwed on, even in the case of highly preloaded bolts, and also enables a highly loadable threaded connection. For this purpose, the play is monotonically increasing in the axial direction.

A component, provided with a thread has increased play in the axial direction in comparison with a standard thread, which allows nuts to be screwed on, even in the case of highly preloaded bolts, and also enables a highly loadable threaded connection. For this purpose, the play is monotonically increasing in the axial direction.

A lock-washer of conical, annular or other shapes capable of elastic flattening when the threaded connection, of which it is a part, is tightened and having tabs along the perimeter of the central hole. For most embodiments the tabs' tips form a circle of a diameter slightly larger than that of a threaded part which is to pass through the central hole. When during tightening the axial force acting on the lock-washer reaches a pre-determined level and the lock-washer flattens, its central hole diameter decreases and the tab tips enter the thread channel, which will cause the thread to jam, thus preventing further tightening, thereby limiting the axial load in the threaded connection to a pre-determined level. Another embodiment provides a lock-washer which compresses and expands radially during tightening providing a visual and/or audible signal for the worker when said expansion and a corresponding axial load reach the designated level.

A lock-washer of conical, annular or other shapes capable of elastic flattening when the threaded connection, of which it is a part, is tightened and having tabs along the perimeter of the central hole. For most embodiments the tabs' tips form a circle of a diameter slightly larger than that of a threaded part which is to pass through the central hole. When during tightening the axial force acting on the lock-washer reaches a pre-determined level and the lock-washer flattens, its central hole diameter decreases and the tab tips enter the thread channel, which will cause the thread to jam, thus preventing further tightening, thereby limiting the axial load in the threaded connection to a pre-determined level. Another embodiment provides a lock-washer which compresses and expands radially during tightening providing a visual and/or audible signal for the worker when said expansion and a corresponding axial load reach the designated level.

To provide a steel for high-strength bolts, which can exhibit the sufficient delayed fracture resistance under the severe environment, and also has excellent bolt formability. The steel for high-strength bolts of the present invention includes C: 0.10 to 0.30%; and Ni: 0.4 to 0.7%, with the chemical composition being appropriately adjust, and satisfies the following formulas (1) and (2):
0.85[C]+[Si]/7+[Mn]/5+[Ni]/20+[Cr]/9+[Mo]/21.3(1)
[C](0.07[Mo]+0.20[V])0.20(2).

To provide a steel for high-strength bolts, which can exhibit the sufficient delayed fracture resistance under the severe environment, and also has excellent bolt formability. The steel for high-strength bolts of the present invention includes C: 0.10 to 0.30%; and Ni: 0.4 to 0.7%, with the chemical composition being appropriately adjust, and satisfies the following formulas (1) and (2):
0.85[C]+[Si]/7+[Mn]/5+[Ni]/20+[Cr]/9+[Mo]/21.3(1)
[C](0.07[Mo]+0.20[V])0.20(2).