Fastening art with double nuts for a dual-threaded screw structure is provided, in which loosening is not created even if the structure is subjected to vibration. A spring washer is caused to intervene between the nuts, when double nuts of an inner nut and an outer nut are screwed onto a thread portion on which dual-threaded screw is formed. Only by tightening the outer nut, also the inner nut is tightened and the spring washer is compressed. Both axial force for clamping the fastened member and axial force between the nuts can be secured with the spring washer, so that loosening does not occur easily.

A washer is provided. The washer includes a first material and a second material. The first material surrounds the second material. The first material is harder than the second material. The second material has a threaded hole in its center. The washer may be part of a system comprising a nut, a bolt with a bolt head and a threaded bolt screw, and a substrate. The washer is first fixed over the threaded the bolt screw, a nut is then fixed over the washer on the threaded bolt screw, such that a pressure formed to inflate and squeeze the threads of the threaded hole in the second material of the washer to mate better with the threads of the threaded bold screw, thus providing an anti-loosing effect.

A method for preloading a bearing includes releasably, threadably, and directly attaching an attaching member to a circumferential outside surface of an exposed end of a threaded shaft of an axle or spindle. A frame is axially separated from, and coupled to, the attaching member. A plurality of extensions extends from the frame axially past the attaching member toward the wheel hub assembly. An adjustment mechanism moves the frame and the plurality of extensions axially towards the wheel hub assembly to contact the wheel hub assembly and/or the bearing to apply a preload to the bearing within the wheel hub assembly.

A bolt includes a main-bolt head, a threaded shaft, and a deformable-bolt head component. The main-bolt head has a recess. The threaded shaft extends from the main-bolt head. The threaded shaft has an external thread wrapped therearound. The deformable-bolt head component has an outer flange and an interior threaded bore. The outer flange of the deformable-bolt head component is coupled to the main-bolt head such that a relief space is formed between the deformable-bolt head component and the recess.

A method for preloading a bearing includes releasably, threadably, and directly attaching an attaching member to a circumferential outside surface of an exposed end of a threaded shaft of an axle or spindle. A frame is axially separated from, and coupled to, the attaching member. A plurality of extensions extends from the frame axially past the attaching member toward the wheel hub assembly. An adjustment mechanism moves the frame and the plurality of extensions axially towards the wheel hub assembly to contact the wheel hub assembly and/or the bearing to apply a preload to the bearing within the wheel hub assembly.

A method for preloading a bearing includes releasably, threadably, and directly attaching an attaching member to a circumferential outside surface of an exposed end of a threaded shaft of an axle or spindle. A plurality of extensions extends from a frame and is moved axially toward a wheel hub assembly to apply the preload to the bearing in a distal direction past the attaching member toward the wheel hub assembly. The extensions are configured to contact at least one of a wheel hub or a bearing of the wheel hub assembly when the attaching member is directly attached to the threaded shaft. An automated adjustment mechanism is configured to move the frame and the plurality of extensions axially towards the wheel hub assembly to apply a preload to the bearing within the wheel hub assembly.

Methods and apparatus for preloading a bearing are provided. These methods and apparatus include preload monitoring devices whereby the mechanic can accurately monitor and regulate the preload on a bearing or bearing assembly. Aspects of the invention may also be used to adjust the endplay on a bearing or a bearing assembly. In one aspect, the preload on the bearing is transmitted through a housing having a fluid pressure that can be detected and monitored. An apparatus for precisely rotating a nut and a tool for precisely rotating a nut are also provided. A bearing retaining nut arrangement that permits the loading or evaluating of a bearing inner race is also provided. The bearing retaining nut arrangement includes a first load-setting nut, a lock washer, and a second jam nut that secures the arrangement to a shaft.

Methods and apparatus for preloading a bearing are provided. These methods and apparatus include preload monitoring devices whereby the mechanic can accurately monitor and regulate the preload on a bearing or bearing assembly. Aspects of the invention may also be used to adjust the endplay on a bearing or a bearing assembly. In one aspect, the preload on the bearing is transmitted through a housing having a fluid pressure that can be detected and monitored. An apparatus for precisely rotating a nut and a tool for precisely rotating a nut are also provided. A bearing retaining nut arrangement that permits the loading or evaluating of a bearing inner race is also provided. The bearing retaining nut arrangement includes a first load-setting nut, a lock washer, and a second jam nut that secures the arrangement to a shaft.

An apparatus for preloading a bearing includes an attaching member, a frame, a plurality of extensions, and an adjustment mechanism. The attaching member is releasably attachable to a threaded shaft of an axle or spindle of a wheel hub assembly. The frame is axially separated from, and coupled to, the attaching member to allow the frame to move relative to the attaching member in an axial direction along the longitudinal axis. The plurality of extensions is configured to contact at least one of a wheel hub or a bearing of the wheel hub assembly when the attaching member is attached to the threaded shaft. The adjustment mechanism is configured to move the frame and the plurality of extensions axially towards the wheel hub assembly to apply a preload to a bearing within the wheel hub assembly.

Methods and apparatus for preloading a bearing are provided. These methods and apparatus include preload monitoring devices whereby the mechanic can accurately monitor and regulate the preload on a bearing or bearing assembly. Aspects of the invention may also be used to adjust the endplay on a bearing or a bearing assembly. In one aspect, the preload on the bearing is transmitted through a housing having a fluid pressure that can be detected and monitored. An apparatus for precisely rotating a nut and a tool for precisely rotating a nut are also provided. A bearing retaining nut arrangement that permits the loading or evaluating of a bearing inner race is also provided. The bearing retaining nut arrangement includes a first load-setting nut, a lock washer, and a second jam nut that secures the arrangement to a shaft.