Abstract: A method for measuring shear load of a fastening tool, which comprises the steps of: positioning an optical fiber sensor on a surface of a fastening tool to be subjected to a measurement, or within the tool but near the surface thereof, so that the optical fiber sensor is positioned along a direction of an axis the fastening tool; and measuring the shear load acting on the fastening tool on the basis of a change in an optical characteristic of the optical fiber sensor that directly corresponds to a deformation of the fastening tool when the shear load is applied to the fastening tool.

Abstract: A configuration for use with a processor that incorporates a suite of agents in a “flat” hardware architecture and superimposes thereon a self-forming, self-healing, hierarchical architecture implemented in software. Embodiments may be employed in various applications, such as maintaining network integrity. In one embodiment a building security monitoring network provides for automated network agents to each be capable of communication with any other automated agents on a network at network startup. Shortly after network initialization, the software architecture is superimposed on the flat hardware architecture, re-arranging communication links to provide an efficient hierarchy of control and substituting working agents for compromised agents as necessary in the network. All of this is done in a “live” network, not requiring shutdown, or even reduced operation to accomplish.

Abstract: A system is provided for both reading an optical identification mark, such as a bar code, on a fastener and for making ultrasonic load measurements in the fastener using a single probe for use during fastener installation with assembly tools and for the inspection of load in preinstalled fasteners. The probe includes both a fiber optic imaging cable and at least one electrical conductor. The fiber optic imaging cable is optically coupled to an imaging device such as a bar code reader allowing the bar code reader to be located remote from the fastener. The electrical conductor provides an electrical connection from the ultrasonic transducer on the fastener to load measurement instrumentation. The probe is further capable of providing illumination of the bar code to facilitate reading of the bar code.

Abstract: A fixing element and inspection system for examining the status of the fixing element are provided in the present invention. The fixing has a sensing material disposed therein for transforming the force acting on the fixing element into an electrical signal. A signal processing unit, powered by a radio frequency circuit, is coupled to the sensing material for transforming the electrical signal into a readable signal and then transmitting the readable signal to the inspection system through radio frequency so as to monitor the status of the fixing element. By means of the present invention, it is capable of inspecting and monitoring the status of a great amount of fixing elements rapidly and precisely, especially in occasion that extreme safety should be highly concerned, for example, fixing elements secured to the airplane.

Abstract: A load indicating insert visually displays fastener loading during tightening and use of a fastener. First and second levers are positioned by a connective cartridge substantially within a fastener bore to provide a compound. amplified indication of loading as a function of the elongation or deformation of the fastener. The first lever is connected at an internal pivot point of a cartridge with a lower end resting on an abutment within the fastener bore. As the abutment moves the first lever during elongation, the second lever moves relative to a visual loading scale. As the fastener is loaded and unloaded, varying elongation of the fastener causes displacement of the abutment and movement of the indicator back and forth along the load indicating scale.

Abstract: A target pressure value is determined during the learning mode. Subsequent pressure values are then compared to the target value. For example, a first connection is tightened in a conventional manner, while its pressure is monitored during the learning mode. If the tightening process went well, then an operator pushes a button that tells the monitor to remember how much pressure was used on the tongs to tighten the first connection. The pressure value of that first joint then becomes the target pressure value for any subsequent joints. As additional joints are tightened, the pressure applied to the tongs is monitored and compared to the first one to ensure that all the joints are as good as the first one within an allowable tolerance.

Abstract: A load indicating member is provided with an identifying element which can be accessed and used to determine ultrasonic measurement parameters specific to the load indicating member to provide more precise and more reliable load measurements by compensating for differences resulting from manufacturing variations in individual load indicating members. The parameters specific to the load indicating member can be stored in coding applied to the load indicating member or in a database that can be accessed remotely, for example, using the Internet.

Abstract: An ultrasonic load measurement transducer is mated with a thread-forming fastener to provide a load indicating thread-forming fastener that can be used for the precise and reliable assembly of critical bolted joints, such as those in the automobile and aerospace industries, among others. Steps can then be taken to accurately measure and control the load in the thread-forming fastener during tightening, and to inspect the load in the thread-forming fastener after assembly. A similar result can be achieved for a thread-locking fastener by mating an ultrasonic transducer with the thread-locking fastener assembly.

Abstract: The apparatus of the present invention comprises a tool having a threaded member which is characterized by a cylindrical shaft or spindle with a surrounding body or handle. The shaft and body are operably engaged by means of a series of magnets in the spindle and the body, and the operable engagement releases once the torque force on the threaded member exceeds the magnetic force between the body and the spindle. In the method of the present invention, the user can calibrate and adjust the torque limit of the assembly by attaching a calibration bar of predetermined length to the threaded member and then rotating the tool over a scale such that the calibration bar contacts the surface of the scale. The user can then adjust a set screw which alters the length of the shaft and alters the magnetic force between the body and the spindle and correspondingly alters the torque limit of the tool to a desired level.

Abstract: A fastener assembly and method are provided. In one embodiment, the fastener assembly comprises a nut compatible with a threaded shaft. A rotation indicator having at least one indicator extension is attached to the nut. At least one protruding structure extends from the nut. The protruding structure interferes with the indicator extension when the nut is rotated on the threaded shaft and the rotation indicator is compressed between the nut and a surface.

Abstract: A mechanical-quantity measuring device capable of measuring a strain component of structure deformation for an object to be measured in a particular desired direction with long life, high reliability and high precision. A strain sensor is formed on a semiconductor substrate. Impurity-diffused layers considering the crystal orientation of the semiconductor single crystalline substrate are used to form a Wheatstone bridge circuit on the substrate. The Wheatstone bridge circuit can operate on one substrate since the semiconductor single crystal has the anisotropy of piezoresistance effect.

Abstract: A hydraulic threaded bolt clamping device for tightening and releasing threaded bolts has a pressure medium supply connected to a pressure medium connector. A cylinder rests against a machine part that is to be clamped and a periodically pressure-loaded piston is guided seal-tightly in the cylinder and rests against a threaded bushing screwed onto the threaded bolt. A control device actuates the pressure medium supply for supplying pressure medium to the bolt clamping device. After a nominal value corresponding to a nominal prestressing force has been reached the pressure medium supply is switched off. The nominal screw prestressing force or a corresponding nominal pressure of the pressure medium supply is preset by an input device. A measuring device measures relative displacement of the threaded end of the bolt relative to the cylinder. An evaluation device determines residual actual screw prestress after pressure relief of the bolt clamping device.

Abstract: A tightening method yielding a precise control of the resulting clamping force, in which the tightening operation is performed in two steps, and the stress level is always kept within the limits of the elastic portion of the stress×strain curve. The method employs a single or multi-spindle power wrench controlled by a computer, provided with measuring means for the precise sensing of applied torque and turn angle in real time. The method comprises in a preferred embodiment a first and a second tightening operations, the data collected during the first operation being inputted to the computer which calculates the amount of torque to be applied to the fastener in the second and final tightening operation according to an algorithm which also comprises checking steps to ascertain that the results fall within the preset values, tolerances and scatter limits.

Abstract: An ultrasonic load measurement transducer is mated with a thread-forming fastener to provide a load indicating thread-forming fastener that can be used for the precise and reliable assembly of critical bolted joints, such as those in the automobile and aerospace industries, among others. Steps can then be taken to accurately measure and control the load in the thread-forming fastener during tightening, and to inspect the load in the thread-forming fastener after assembly. A similar result can be achieved for a thread-locking fastener by mating an ultrasonic transducer with the thread-locking fastener assembly.

Abstract: A load indicating member is provided with an identifying element which can be accessed and used to determine ultrasonic measurement parameters specific to the load indicating member to provide more precise and more reliable load measurements by compensating for differences resulting from manufacturing variations in individual load indicating members. The parameters specific to the load indicating member can be stored in coding applied to the load indicating member or in a database that can be accessed remotely, for example, using the Internet.

Abstract: For limiting twist of a measurement transmitter housing relative to a sensor element, onto which the measurement transmitter housing is screwed, axial barriers are provided, so that the axial position of the measurement transmitter housing relative to the sensor element is limited to a range between two extreme positions defined by the axial barriers. The axial barriers are preferably formed by a ring, which engages both an annular groove in an outer, lateral surface of the sensor element and an annular groove in a cylindrical duct of the transmitter housing.

Abstract: A safety device (10) comprises a plurality of wheel nut position indicators (30) captively but rotatably mounted in a holder (12). The position indicators are attachable to respective wheel nuts (40) by means of fastener covers (50). When attached, the fastener covers (50) act to secure the device to a wheel and to transfer any rotational movement, i.e. loosening, of a wheel nut (40) to an associated position indicator (30). The indicators (30) each have an indicator portion, e.g. a triangular pointer (34) and are so arranged that this portion emerges from the holder and hence becomes visible when any such rotation occurs. By removing a fastener cover (50) an indicator (30) is disengaged from a wheel nut (40) and the individual wheel nut can be tightened without having to remove the entire device (10).

Abstract: A fastener or other structural component for wireless sensing of applied tensile load. The fastener includes an elongate body with a bore that extends within the body. A grounding pin is positioned within the bore and attached to the body within the bore. The fastener includes a wireless transponder, such as a radio frequency identification (RFID) transponder or tag, that is mounted on a head provided at the end of the body and exposed to the bore, such as by positioning the RFID tag in a recessed surface of the head or extending the bore through the head. The transponder generates a response signal with a unique identifier in response to a radio frequency signal from a transmitter. The grounding pin contacts and grounds the transponder to block transmittal of the response signal when a tensile load applied to the fastener is less than a minimum tensile load value.

Abstract: An apparatus for securing a measuring sensor on a pipeline. The mounting-housing is positionable on the pipeline, with the mounting-housing being embodied, and coordinated with the measuring sensor, in such a manner that a force, which acts on the mounting-housing in the direction of the pipeline, acts at least partly on the on the measuring sensor in the direction of the pipeline; and that at least one screw unit is provided, via which an adjustable force can be exerted on the mounting-housing in the direction of the pipeline.

Abstract: The present invention provides a strain detector improved in output characteristic, in which no internal stress is generated in strain resistance elements even with it fixed on a fixing member. The strain detector is configured in that a detection hole is provided nearly at the center of a insulating substrate, a fixing hole is formed at the position of peripheral end, a portion around the detection hole is pressed by a pressing member, one holding member and the other holding member are provided with fixing holes opposing to the fixing holes of the insulating substrate, and the peripheral end of the insulating substrate is fixed by the fixing member inserted. Accordingly, the detection hole in the insulating substrate is peripherally displaceable in a vertical direction with respect to one holding member and the other holding member.

Abstract: A wireless-enabled tightening system for fasteners is disclosed. The system includes a visual designator configured to project an indicator onto a workpiece. The system also includes a torque wrench comprising a wireless transmitter and a means for identifying whether the correct torque has been applied to a fastener on the workpiece and configured to provide a feedback for a user. The system also includes a camera configured to capture an image of the workpiece when an appropriate amount of torque has been applied to the fastener. The system further includes a microprocessor for determining sequence of the fastener and identifying the tightened fastener.

Abstract: This load cell attachment structure includes a male screw which is formed on a load sensing part of the load cell, a nut which attaches the load cell to the attachment plate by engaging with the male screw, and a wave washer which is disposed between the attachment plate and the nut.

Abstract: Tightening of a bolt is controlled by monitoring the change in round trip time of propagating longitudinal ultrasonic waves through the bolt and the reflection of these waves at the end of the bolt. The round trip time of the longitudinal waves through bolt is continuously measured and monitored in real-time. Elongation of the bolt as it is being tightened is determined based on the change in the round trip time of the longitudinal waves, which provides the level of bolt tension and joint clamp load. In determining the bolt elongation, an elongation-dependent wave speed has been formulated and used in-real time. When the elongation of the bolt reaches a predetermined level, tightening is automatically stopped.

Abstract: A reusable washer assembly apparatus includes a generally ring-shaped flexible inner member, a generally ring-shaped outer member, a distal washer member, and a proximate washer member. The outer member is disposed around the inner member and is adapted for at least partial rotation about the inner member. The flexible inner member and outer member define a first gap between each other. The distal washer member communicates with a first surface of the inner member and the proximate washer member communicates with a second surface of the inner member. An applied force to at least one of the proximate washer member and the distal washer member causes the flexible inner member to deform and at least partially fill the first gap thereby preventing rotation of the outer member when the applied force reaches a threshold value.

Abstract: A device for measuring pre-stressing force in a bolt/nut connection, comprising a screw nut that is provided with a sensor means for sensing the pre-stressing force. The nut (1) is of standard design, and the nut itself constitutes a sensor body in that, in the outer peripheral surface (2) of the nut, there is machined at least one recess (3) in which there is placed a sensor (4) that is adapted for sensing mechanical stress in the nut, and for providing a signal representing the stress, for transmission to an external recording device.

Abstract: The invention relates to a control device for non-positive connections, especially screw connections. The device includes two force application elements and a measuring element arranged therebetween. The measuring element is at least partially provided with a layer having a force sensory effect. The surface of the layer is provided with elevations for receiving a force applied by the force application elements.

Abstract: A test device comprises a base and a first fixture coupled to the base. The first fixture holds a first portion of an electronic device mounted in the test device. The test device includes a second fixture rotatably coupled to the base and a lever coupled to the second fixture. The second fixture holds a second portion of the electronic device mounted in the test device. The test device also includes an actuator that forcibly moves the lever to rotate the second fixture and apply a torsion stress on the electronic device mounted in the test device. The test device may be used to test the functionality of electronic devices, such as small form-factor disc drives, while under torsion stresses.

Abstract: The present invention provides an innovative method and apparatus for determining continuous, visual clamp load status during tightening and throughout the life of a fastener. The present invention provides a pair of levers suitably configured and positioned within a fastener to provide an amplified indication of the deformation of the fastener as a load is applied to the fastener. In accordance with one aspect of the invention, a first lever is connected at an internal pivot point of a cartridge with the lower end of the first lever resting upon an abutment within the fastener, while the upper end displaces the lower end of a second lever such that movement of the upper end of the second lever is amplified with respect to movement of the lower end of the first lever. As the fastener is tightened, the fastener will elongate causing the abutment to move away from the lower end of the first lever.

Abstract: A robust, easy to mount probe sensor includes an elongated body enclosing a sensor element and an integral flange extending away from the body. The body and flange are formed of material having a relatively low characteristic yield point. First and second generally parallel closely spaced through passages extend through the flange. An insert formed of material having a relatively high characteristic yield point is disposed in one of the passages. A fastener including a shank portion which extends through the other passageway includes an enlarged head which overlays the insert containing passageway and engages an attachment structure to effect directed compressive loading of the probe sensor flange.

Abstract: A bolt with a function of measuring strain, comprising a Wheatstone bridge circuit comprising a strain sensor and a dummy resistor, a translate circuit that amplifies a signal from the Wheatstone bridge circuit to convert the same into a digital signal, a transmitting circuit that transmits the digital signal outside the bolt, and a power circuit, by which electromagnetic wave energy received from outside the bolt is supplied as a power source for at least any one of the circuits.

Abstract: An object comprising a body part having an electrically insulating outer surface part, and a first layer arranged on the outer surface part. The first layer is formed by one or more electrically conducting materials and defines one or more conducting paths between a first area of the outer surface part and a second area of the outer surface part. Thereby electrical signals may be transferred between the first and second area parts. The layer further defines a sensing device, which is thereby embedded into the object. The object is provided with a threaded portion defining an outer thread. Thereby the object may easily be fitted into an opening having a mating inner thread. The object may be in the form of an ordinary bolt with a sensing device embedded in a surface part thereof.

Abstract: A method and an apparatus serve for determining the deflection of a fastener, especially a screw.

Abstract: A structural bolt security apparatus includes a security nut forming a threaded central hole for a bolt; the security nut has a groove in an upper surface and/or a side surface. At least one groove is at least partially separated from the threaded central hole by the upper surface. In one embodiment, a security nut has a plurality of electrical contacts, logic electronics configured for monitoring electrical resistance across the electrical contacts, and a transmitter for broadcasting security data generated by the logic electronics. In one embodiment, a structural bolt security apparatus includes a security nut and an outer sleeve. Structural bolt security systems described herein include a security nut, a security socket, and a security wrench. The systems may be equipped with RFID chips for recognition of matched security nuts and security sockets, and/or with GPS transceivers for broadcasting security wrench position information.

Abstract: A fluid pressure sensor (1) for measuring the pressure of a fluid comprises a diaphragm portion (12) which is a strain generating body, a silicon oxide film (21) as an insulating film, and a strain gauge (20) made of crystalline silicon, and austenitic precipitation hardening type Fe—Ni heat-resisting steel excellent in mechanical strength and corrosion resistance is used for the diaphragm portion (12). The silicon oxide film (21) is formed with the internal stress thereof adjusted to the range from ?150 to 130 MPa. With this feature, the fluid pressure sensor (1) ensures high precision and reliability, and may be used even for measurement of a highly corrosive fluid.

Abstract: Apparatuses and methods for structurally testing fasteners are described herein. A fastener test apparatus configured in accordance with one aspect of the invention includes a first support member configured to support a head portion of a fastener, and a second support member configured to support a locking feature on a shaft portion of the fastener. The test apparatus can also include a force measurement device configured to be operably sandwiched between the first support member and the second support member. The force measurement device can be used to measure fastener preload. The test apparatus can further include first and second fixtures for performing an ultimate tensile test of the fastener. In this regard, the first fixture can be configured to exert a first force against the first support member in a first direction, and the second fixture can be configured to exert a second force against the second support member in a second direction opposite the first direction.

Abstract: The invention relates to a device for adjusting and/or verifying the axial force in screwed connections. The inventive device contains a control device for limiting an axial force acting between two force application elements of the screwed connection. To this end, the invention provides that the control device will record signal values from a measuring element whose electrical resistance varies according to the acting axial force.

Abstract: A force sensor assembly includes a force sensor, a first support member, a threaded portion, an opening made in the first support member, a nut, a restricting member and a spacer. The nut is screwed onto the threaded portion which is inserted through the opening. The restricting member is provided between the force sensor and the nut. The spacer, which is provided between the force sensor and the nut, is deformable in a direction of its thickness. The shape of the spacer is adapted to avoid interference with the restricting member. Before the nut is tightened onto the threaded portion, a summation of thickness for the first support member and the spacer is adapted to be not less than a height of the restricting member. The nut is tightened up with a predetermined fastening torque until the spacer deforms so that the nut strikes the restricting member.

Abstract: A metal cap 12 is fitted over a vessel (vial 2), into which a rubber plug 4 is driven, and using a pressure block 10, a load is applied to the cap 12 through the top surface 12b thereof to maintain the rubber plug 4 compressed. Under this condition, a tightening roller 14 folds a skirt (lower end 12c of a cylindrical portion 12a) of the cap 12 inwardly to perform a tightening operation. Subsequently, the load applied to the top surface 12b of the cap is once released, and then a load is applied again starting from a value FB which is less than the load FA applied during the tightening operation, gradually increasing to a higher value. In the course of increasing the load, a load FC at the instant when a displacement in the elevation of the top surface of the cap is detected, and this load FC is determined to be a seal load upon completion of the tightening operation. By detecting the load FC upon completion of the tightening operation, a seal capacity of the rubber plug 14 can be confirmed.

Abstract: The present invention provides an axial bolt force measuring instrument for measuring an axial force of a bolt for a hub that couples a wheel and an axle of a vehicle, where the instrument is provided with a setting portion that sets a predetermined axial force of the bolt, a tapping portion that taps the bolt, a sound collecting portion that collects tap sound generated by tapping the bolt with the tapping portion, a frequency measuring portion that measures a frequency of the tap sound collected by the sound collecting portion, an axial force converting portion that converts the frequency of the tap sound measured by the frequency measuring portion into an axial force of the bolt, a comparing portion that compares the set axial force set in the setting portion with the converted axial force converted in the axial force converting portion from the frequency of the tap sound, and a display portion that displays a result of comparison in the comparing portion.

Abstract: A component positioning device including a first support device, the first support device having a first upper structure and a first lower structure, the first upper structure including a first inner wall disposed at a first predetermined angle and defining a first component structure, and the first lower structure defining a first arbor cavity and a first fastening cavity, the first fastening cavity being communicated with the first arbor cavity. A second support device is provided having a second upper structure and a second lower structure, the second upper structure including a second inner wall disposed at a second predetermined angle and defining a second component structure, and the second lower structure defining a second arbor cavity and including at least one protruding member and an adapter device having an adapter wall, wherein the adapter wall defines an adapter cavity, an adapter fastening cavity and an adapter notch cavity.

Abstract: A preload indicating washer assembly that operates in the elastic region for a rated compression is disclosed. Because it operates in the elastic region, the preload indicating washer assembly resumes its original shape when the compression is decreased or removed. The washer assembly elastically deforms again to the same extent as its original deformation when the predetermined compression is restored. Thus the washer assembly will indicate the proper fastener preload when used for multiple loading cycles or in multiple locations.

Abstract: A method of controlling a motor (106) used to drive a screwdriver bit (105) such that screws (107) are seated to the optimum point of grip between the screw (107) and the work piece material. An electronic control circuit controls the speed and output torque of the motor (106). The control system utilizes pulse width modulation (PWM) to control motor (106) speed and torque. The PWM signal controls the duty cycle of the transistors that supply current to the motor (106). The amount of current flowing through the motor (106) coils is proportional to the amount of torque the motor (106) is producing. Motor (106) current is measured as voltage produced across a precision resistor that is in series with the motor (106) coils. As the current in the motor (106) increases, the voltage across the resistor increases (V=IR).

Abstract: An apparatus and method for measuring the tension in bolts, screws, rivets, and other fasteners, is disclosed wherein the deformation of the fastener head is measured (or the end of fastener in such cases as there is not a distinct formed head, for example stud bolts). The deformation generally is an analytic function of the tension in the fastener. The deformation is a continuous two-dimensional distribution over the surface of the fastener head, which allows redundant measurement and therefore more reliable measurement of fastener total axial tension, and also allows in some instances an evaluation of the bending stresses in the fastener from the distortion of the deformation pattern on the head. An advantage of the invention is that the length of the fastener or its temperature need not be known. The measurements can be determined by optical, capacitance, optical imaging, air gauging and piezoresistive techniques.

Abstract: A measuring device (1; 21; 33) for controlling an installation torque of a fastening element (4; 32) and securable to engagement means (3; 35) of the fastening element (4; 32), includes an indicator (5; 24) for a visual display of the installation torque, a plurality of microcapsules filled with a dispersible color die and supported on the indicator (5; 24), and a transparent, at least regionwise, covering (7.1; 7.2; 22) provided on an outer surface of the indicator (5; 24); and an opening (27) through which a fastening element (4; 32) can extend.

Abstract: The invention relates to a threaded bolt provided with measurement planes for use in ultrasonic length measurement. After the threaded bolt has been fixed in a connection, such measurement is performed to determine the length change of the threaded bolt, in order to find out the tension within the threaded bolt in that way.

Abstract: A load indicating member is provided with a permanent identifying mark which can be read and used to determine ultrasonic measurement parameters specific to the load indicating member to provide more precise and more reliable load measurements by compensating for differences resulting from manufacturing variations in individual load indicating members. The parameters specific to the load indicating member can be stored in coding applied to the load indicating member or in a database that can be accessed remotely, for example, using the Internet.

Abstract: A test method for determining, quantifying, and qualifying the stress-relaxation characteristics of a sealant material compound comprising applying a sealant material layer between a first plate and a second plate, disposing a fastener assembly through the plates, and providing tension preload upon the fastener assembly so as to compress the plates together. The elongation of the fastener assembly is measured and the test assembly is heated and cooled under controlled parameters and the elongation of the fastener assembly is again measured. The stress-relaxation of the sealant material compound is correlated to the corresponding change in fastener assembly elongation for the purposes of measuring, quantifying, and qualifying the sealant material compound.

Abstract: An instrument pin member is provided that is capable of measuring bending moments and optionally of measuring bending and axial strain in real or near real time. The instrumented pin member includes a pin member body disposed about a pin member axis, wherein the pin member body includes a bending portion. A sensing device is positioned at the pin member body within the bending portion for sensing a bending strain in the bending portion exclusive of a net axial strain, and for outputting a sensor measurement signal representative of the bending strain. A sensor measurement signal output device is provided for outputting the sensor measurement signal from the sensing device. A related system includes a plurality of pin members, among other things. Related methods also are disclosed.

Abstract: A delashing assembly includes a tightening device for tightening a nut in relation to a main shaft supported on bearings and a wireless interface, wherein torque information is received by the tightening device over the wireless interface. A main shaft and main nut assembly, as well as a steering system, may include the delashing assembly. A method of delashing the main shaft and main nut assembly includes providing a tightening device on a first end of the main shaft and sending torque information from a second end of the main shaft to the tightening device over the wireless interface.

Abstract: A variably amplified load indicating fastener includes a fastener (100) detachably secured to a load indicator via a base member. The fastener (100) has an abutment which is moved by a change in length under an applied load. The load indicator includes a dial plate (16), a needle (24) pivotally supported by the plate (16), a compensating slot (36), a driving slot, an elongated U-shaped element (50) disposed in the direction in which the load is applied when the fastener (100) is in use, and a first reference mark (40a). One side of the U is rigidly attached to the fastener. The closed end of the U is proximate to and movable by the abutment. The other side of the U extends through the compensating slot (36) and the driving slot (26). The needle (24) is operatively coupled to the outer end of said second side. A sleeve with a second reference mark fits over the outer circumference of both the load indicator and the base member.