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 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 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 fastening device for fastening a bolt to a fastening target object, wherein the bolt has a bolt head female screw section in an inner circumferential surface of a recess provided in an upper surface of a bolt head section. The fastening device includes a tension rod having a rod male screw section engaging the bolt head female screw section; a drive socket circumferentially surrounding the tension rod and having a lower end section with a grasper for laterally grasping the bolt head section; a supporter circumferentially surrounding the drive socket and having a lower end section protruding downward beyond a lower end section of the drive socket; a sensor for sensing compression force acting on the supporter in the upward/downward direction; a first motor for rotating the tension rod around an axis extending in the upward/downward direction; and a second motor for rotating the drive socket around the axis.

An expansion bolt comprises a bolt having an end-face anchoring means for the tension-resistant anchoring of the bolt on or in a first assembly part, which bolt has a truncated-cone-shaped cone section and a bolt threaded section in its end section opposite to the anchoring means with a nut screwed thereon, an expansion sleeve having a cylindrical lateral surface and an inner cone contour interacting with the cone section of the bolt, and a clamping device supported on a second assembly part for widening the expansion sleeve and applying an axial clamping force to the assembly parts to be connected together. The cone section of the bolt is tapered in the direction toward its anchoring means and the inner cone contour of the expansion sleeve is tapered in the same direction. The expansion sleeve bears a clamping flange protruding outward in the radial direction on its end opposite to the inner cone contour. The clamping device comprises a clamping ring having an axial passage opening. The expansion sleeve engages through this passage opening, permitting an adjustability of the expansion sleeve in relation to the clamping ring in the axial direction, and protrudes with its clamping flange beyond a peripheral region of the clamping device enclosing the passage opening. The clamping ring also comprises multiple pressure bolts arranged circumferentially distributed, which mesh with their thread in internally threaded holes extending through the clamping ring in the axial direction and act with their bases indirectly or directly against the second assembly part to widen the expansion sleeve and apply an axial clamping force to the assembly parts. Furthermore, a connection assembly having such an expansion bolt is described.

An expansion bolt comprises a bolt having an end-face anchoring means for the tension-resistant anchoring of the bolt on or in a first assembly part, which bolt has a truncated-cone-shaped cone section and a bolt threaded section in its end section opposite to the anchoring means with a nut screwed thereon, an expansion sleeve having a cylindrical lateral surface and an inner cone contour interacting with the cone section of the bolt, and a clamping device supported on a second assembly part for widening the expansion sleeve and applying an axial clamping force to the assembly parts to be connected together. The cone section of the bolt is tapered in the direction toward its anchoring means and the inner cone contour of the expansion sleeve is tapered in the same direction. The expansion sleeve bears a clamping flange protruding outward in the radial direction on its end opposite to the inner cone contour. The clamping device comprises a clamping ring having an axial passage opening. The expansion sleeve engages through this passage opening, permitting an adjustability of the expansion sleeve in relation to the clamping ring in the axial direction, and protrudes with its clamping flange beyond a peripheral region of the clamping device enclosing the passage opening. The clamping ring also comprises multiple pressure bolts arranged circumferentially distributed, which mesh with their thread in internally threaded holes extending through the clamping ring in the axial direction and act with their bases indirectly or directly against the second assembly part to widen the expansion sleeve and apply an axial clamping force to the assembly parts. Furthermore, a connection assembly having such an expansion bolt is described.

A method of fastening gearbox housing components together, comprising: selecting a gearbox housing fastener comprising a straight shaft having a longitudinal axis, a first threaded portion, a single cylindrical central portion, and a second threaded portion, wherein the first and second threaded portions are separated by the cylindrical portion, wherein the cylindrical portion comprises a single reduced diameter that is less than first and second minor diameters of the first and second threaded portions, the first and second threaded portions are chamfered, and the fastener comprises a material having a tensile strength along the longitudinal axis that is greater than a sheer strength at the cylindrical portion; and fastening the gearbox housing components together with the fastener, wherein the first and third gearbox housing components are fastened with the first and second threaded portions, and the second gearbox housing component is positioned around the single cylindrical central portion.

A method of fastening gearbox housing components together, comprising: selecting a gearbox housing fastener comprising a straight shaft having a longitudinal axis, a first threaded portion, a single cylindrical central portion, and a second threaded portion, wherein the first and second threaded portions are separated by the cylindrical portion, wherein the cylindrical portion comprises a single reduced diameter that is less than first and second minor diameters of the first and second threaded portions, the first and second threaded portions are chamfered, and the fastener comprises a material having a tensile strength along the longitudinal axis that is greater than a sheer strength at the cylindrical portion; and fastening the gearbox housing components together with the fastener, wherein the first and third gearbox housing components are fastened with the first and second threaded portions, and the second gearbox housing component is positioned around the single cylindrical central portion.

The present invention discloses methods and systems for detecting the health status of a bolt which fastens a rotor blade of a wind turbine. Values of the axial stress/strain of the bolt and motion and orientation data are acquired in different aerial orientations. Values of the prestress/strain and load-stress/strain are obtained using the values of the axial stress/strain and the motion and orientation data. Values of the prestress/strain and load-stress/strain are compared with the reference values. The health status of the bolt, rotor blade, and the wind turbine system is determined based on the comparison results. The method is noninvasive and doesn't affect the function and performance of the bolt and the turbine system.

Systems and methods can include applying, using a nut assembly including a first nut and a plurality of fasteners provided in respective threaded holes of the first nut, a first tensioning force for a stud of a hammer assembly. The systems and methods can also include applying, using the nut assembly, a second tensioning force for the stud of the hammer assembly. The first tensioning force can be applied with the first nut in a first orientation whereby a first end surface of the first nut faces a first direction and a second end surface of the first nut faces a second direction opposite the first direction. The second tensioning force can be applied with the first nut in a second orientation whereby the first end surface of the first nut faces the second direction and the second end surface of the first nut faces the first direction. The second tensioning force can be greater than the first tensioning force.