Abstract: Disclosed is an anti-buckling jig of a fracture toughness test. The anti-buckling jig includes: a first jig unit provided in a form of surrounding one side surface of a specimen; a second jig unit provided in a form of surrounding the other side surface of the specimen; and a screw provided to allow the first jig unit and the second jig unit to be coupled to each other. During the fracture toughness test of the specimen, the first jig unit and the second jig unit simultaneously support both sides of the specimen, so that the specimen is cracked in a single direction.

Abstract: A material testing system that uses at least one hydraulic grip is improved with cable clips that are attachable to a respective lateral side of each hydraulic grip wedge. Each cable clip has another end that extends to engage a cable(s) extending from a corresponding wedge retention spring hole. The cable(s) enable manual extension of a wedge retention spring for engagement and disengagement from the hydraulic grip wedge. The cable clip maintains the cable in a noninterfering position during operational use of the material testing system.

Abstract: An assembly for shock testing a specimen, the assembly including first and second opposing brackets and opposing lower and upper caps. The opposing brackets include lower and upper angled surfaces. The lower cap includes lower angled surfaces configured to engage the lower angled surfaces of the left and right brackets. The upper cap includes upper angled surfaces configured to engage the upper angled surfaces of the left and right brackets. The first and second brackets are configured to be drawn toward each other via fasteners, thereby wedging the lower and upper caps toward each other against the specimen.

Abstract: A tree stand for removably supporting a tree includes a base having a water basin. A plurality of spaced apart jaws are biased upwardly and inwardly of an axis of the base to form an expandable clamp. An end of a trunk of the tree forcibly expands the jaws against their bias as the trunk is inserted into the water basin. The jaws of the clamp engage an outer surface of the trunk as they are biased towards their closed position to hold the tree vertically upright and stable.

Abstract: A method and system is disclosed for determining upper strain limits for materials, and designing devices or components based on determined strain limits.

Abstract: Provided are universal grip systems and method of using universal grip systems to test coupons. According to various examples, a universal grip system includes two grips and two guide posts for supporting the two grips and allowing the two grips to move with respect to each other. Each grip may include one or two wedges. The wedges are used to engage the coupons during testing and provide anti-buckling support and/or anti-rotation support. The wedges are slidably coupled within corresponding grips, which allows the universal grip system to engage and disengage the coupons by moving one grip with respect to another. The grips may be constructed from thermally neutral materials, such as invar 36. The grips may thermally isolated from the guide posts by, for example, a set of spacers disposed between the grips and linear bearing slidably coupled to the guide posts.

Abstract: When a crosshead descends after a specimen is loaded, pins attached to link members contact seat surfaces formed on seat members, and then contact side walls of the seat surfaces. As the crosshead descends further, the pins contacting the seat surfaces press the seat members 31. This pressing force moves a pair of first slide members away from each other as guided by a first rail, and moves a pair of second slide members away from each other as guided by a second rail 24. Consequently, tension loads in biaxial directions perpendicular to each other are applied to the specimen gripped by four chucks 25.

Abstract: A clamping device for clamping a flat material test sample while a material test is carried out is provided. The clamping device includes a substantially cylindrical clamping part, from the free end of which there extends a receiving slot for receiving the material test sample, a pressure ring surrounding the clamping part in the region of the receiving slot, and a pressure sleeve provided between the clamping part and the pressure ring, the pressure sleeve is formed and actuable such that, under radial expansion, it connects the clamping part and the pressure ring together and clamps the material test sample held in the receiving slot.

Abstract: A device and method for treating all types of parts, in particular bones, organs, etc. of the human/animal body, which includes a housing (3), a tool (1) associated with the housing (3), and an actuation unit causing a relative movement between the housing and the tool. The device is designed and constructed to permit process control by the user, while utilizing the specific possibilities of robotics and computer-assisted navigation in such a manner that the position of the tool can be detected, and that the position of the body part being treated can be detected or predetermined, with the actuation unit being activatable in such a manner that it moves the tool within a predetermined work area to a predetermined relative position with respect to the body part being treated.

Abstract: A gravity center neutral eccentric is provided. The gravity-center-neutral eccentric includes an axis of rotation and an eccentric region, wherein the center of mass of the eccentric lies on the axis of rotation. In another embodiment, a center of mass of the eccentric region also lies on the axis of rotation. A measurement device including a gravity center neutral eccentric is also provided.

Abstract: The test fixture includes a housing, a first grip, and a second grip. The first grip and the second grip are each configured to clamp onto an upper surface and lower surface of a material coupon. The test fixture also includes an upper input jaw and a lower input jaw each configured to clamp onto the material coupon near a center of the upper surface and the lower surface of the material coupon. The test fixture is configured to load the material coupon in a first direction and a second direction. The first grip and the second grip are each configured to clamp onto the material coupon at a location which accordingly results in a desired testing ratio regardless of a variation in thickness of the material coupon.

Abstract: An apparatus for testing an angle between first and second legs of a torsion spring includes a board, a limiting block and a pin sandwiching the first leg, a positioning member positioning a main body of the torsion spring with the limiting block, and a test block including a bottom wall slidably contacting the limiting block, and a first sidewall and a second sidewall. Angles between the bottom wall and the first and second sidewalls are respectively minimal and maximal values that equal 180 degrees subtracted by an angle within a qualified range between the first and second legs. The first and second sidewalls is moved toward the second leg in turn. If a bottom end of the first sidewall and a top end of the second sidewall both can contact the second leg, the angle between the first and second legs is qualified. Otherwise, the angle is unqualified.

Abstract: Vibration test arrangements incorporate an isolation device. In order to allow the isolation device to operate on one side only of a component subject to vibration testing a clamp association is provided between isolation elements. An abutment pressure to retain and present the component is generated between the isolation elements utilizing the clamp association and an appropriate displacement mechanism. The displacement mechanism is controlled by a controller in a control loop incorporating a sensor to determine operational characteristics of the arrangement and appropriate drivers for the displacement mechanism.

Abstract: A system for sulfide stress cracking testing comprises an enclosed testing chamber including a fluid bath comprising a liquid saturated with hydrogen sulfide gas. In addition, the system comprises a test fixture disposed in the testing chamber and at least partially submerged in the fluid bath. The test fixture includes a housing having an internal chamber in fluid communication with the fluid bath and a test assembly disposed in the internal chamber. The test assembly comprises a first upper support and a second upper support, a first lower support and a second lower support, and a first platen engaging each of the upper supports and adapted to transfer an applied vertical load to the upper supports. Further, the system comprises a test specimen mounted in the test assembly between the upper supports and the lower supports.

Abstract: A jack assembly, for use in a materials testing system, utilizes both a cam and a resilient push block. The cam, having an progressive eccentric, is situated between the push block and a jaw housing and located partially within a corresponding shallow channel in each such that both channels effectively straddle the cam. The channels accommodate axial rotation of the cam. The push block is formed of a material with an appropriate modulus of elasticity such that bending moments, particularly at ends of the push block and resulting from axial rotation of the eccentric to its top dead-center position, cause the channel in the push block to elastically deform and increasingly and sufficiently deflect against and around the eccentric, thus increasingly pinching the eccentric and securely locking the cam, push block and specimen grip in their proper positions.

Abstract: A creep tester for a precise and accurate creep test includes a movable actuator capable of loading corresponding to change in length of a specimen, a cam actuator operated in association with the movable actuator, and a self weight actuator. The movable actuator includes upper and lower spherical adjusting seats to hold upper and lower portions of the specimen, a spring disposed on the upper spherical adjusting seat to correspond to a minute deformation of the specimen, upper and lower movable tables respectively contacting the spring and the lower spherical adjusting seat, a load cell and a stationary table disposed on the upper movable table, and a movable loading table disposed below the lower movable table to apply a predetermined load to the specimen. The creep tester can perform a precise creep test by continuously applying a constant load without supplementation of hydraulic pressure.

Abstract: A jack assembly, for use in a materials testing system, utilizes both a cam and a resilient push block. The cam, having an progressive eccentric, is situated between the push block and a jaw housing and located partially within a corresponding shallow channel in each such that both channels effectively straddle the cam. The channels accommodate axial rotation of the cam. The push block is formed of a material with an appropriate modulus of elasticity such that bending moments, particularly at ends of the push block and resulting from axial rotation of the eccentric to its top dead-center position, cause the channel in the push block to elastically deform and increasingly and sufficiently deflect against and around the eccentric, thus increasingly pinching the eccentric and securely locking the cam, push block and specimen grip in their proper positions.

Abstract: Positive and negative expansions on the covering surface of essentially cylindrical bodies are measured by mobile measuring pincers which comprise a guiding profile for two adjacently adjustable sliders which are used to clamp the body in a radial direction and to press at least one expansive measuring element on the covering surface by forming a frictional connection. Currently, a first slider, which can be displaced in the direction of clamping on the guide profile by a spindle, preferably comprising integrated torque adjustment, is offset with a centering element on the cylindrical head. Then, a second slider, which can be displaced on the guide profile is arranged with a centering element on the cylindrical body and engaged. The centering elements are clamped on the body between the sliders by pulling the spindle. The measuring element(s) are is/are pressed onto the covering surface of the body in order to form a positive connection.

Abstract: A wedge action grip for tensile or similar testing is provided with a pair of jaws wherein at least one jaw includes a swiveling element with a gripping surface. The jaw and associated swiveling element may have cylindrical swiveling surfaces whereby the swiveling element swivels with a single degree of freedom about a vertical or horizontal axis or may have spherical swiveling surfaces whereby the swiveling element swivels with two degrees of freedom about a point. The two jaws may have different swivel characteristics, and one of the jaws may have a non-swiveling fixed gripping surface.

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: A rheological measurement can be made comprising the steps of disposing a sample to be measured between two opposing surfaces of a fixture; coupling two opposing surfaces of the sample with a corresponding adjacent one of the two opposing surfaces of the fixture to create a secondary sample boundary within the sample; and measuring a rheological parameter of the sample. The two opposing surfaces of the sample are coupled with a corresponding adjacent one of the two opposing surfaces of the fixture by penetrating at least one of the opposing surfaces of the sample with a plurality of protrusions disposed on the corresponding surface of the fixture.

Abstract: A strip ejector removes a longitudinal test strip (12), which has at least one test field for wetting by a fluid, from a measuring device that optically or amperemetrically measures such test strip. The ejector includes a clamping jaw holder (14), and at least two clamping jaws (18) arranged on the clamping jaw holder at a distance from one another. The jaws are moveable relative to one another between a freeing position in which the spacing between their clamping surfaces is larger than the width of a test strip (12), and a clamping position in which their clamping faces respectively engage parallel edges (22) of the test strip (12). An actuating element (24) moveably supported on the clamping jaw holder (14) has at least one control surface 30 arranged at an angle to the movement direction of the actuating element.

Abstract: A method is provided for performing wedge analysis for assessing wedge occurrence and instability in underground openings, such as mines, caves, and the like. The method scales full-span wedge predictions, accounting for both occurrence and instability potential of possible wedge geometries. The method also generates predictions for wedge failure potential and support demand to result in more economical support design for wedges.

Abstract: A holding clamp for use in a testing apparatus for determining tensile and sheer strength characteristics of a reinforcement sheet. The holding clamp defines a channel having at least two adjacent bearing surfaces and an opening to an exterior surface. An elongate clamping bar conforming in cross-sectional shape at least relative to the pair of adjacent bearing surfaces is received within the channel with an end portion of the reinforcement sheet overwrapping the clamping bar and a portion of the reinforcement sheet extends outwardly through the opening for securing in the testing apparatus. A loading mechanism moves the clamp to load the reinforcement sheet, whereby the tensile or sheer strength characteristics can be determined. A method of clamping an end of a reinforcement sheet to be tested for tensile or sheer strength characteristics is disclosed for a testing apparatus.

Abstract: Tensile loading is applied to a notched specimen bar through the base of a fixture grip having a pair of interfitting pieces releasably held assembled in a fixture position in axial abutment with the base and in engagement with the specimen bar by means of a pair of fastener bolts, one of which is loosened so as to act as a hinge accommodating pivotal displacement of the interfitting pieces from the fixture position upon removal of the other fastener bolts.

Abstract: A test device for applying a tensile force to electrical bond sites of a semiconductor device includes jaws (21), adapted to closely engage the surface of the bond site, typically a solder ball (22), while an inner edge portion (23) of each jaw approaches the jaw axis. By closely confining the bond site, the clamping forces exerted can be increased without risk that the bond site will be crushed. In a preferred embodiment the jaws permit slight reshaping of the bond site to increase the area of engagement therewith.

Abstract: The testing apparatus serves to measure the coefficient of friction of a golf ball. The apparatus has a base with a pair of flexure arms which carry inserts between which a golf ball may be pushed under a force in order to flex the flexure arms outwardly. Strain gauges record the flexing of the flexure arms in order to determine the force perpendicular to an insert. A load cell is employed to determine the amount of pushing force on the golf ball in order to determine a force parallel to the surface of the insert. The ratio of the two forces obtained serves as the coefficient of friction of a golf ball.

Abstract: A corrosive environment sensor comprises an elongate metal member having a pair of beam portions, each extending in a length direction between first and second ends of the metal member, and having a crack growth portion formed therein and extending in the length direction of the metal member from a crack starting end toward the second end, wherein the crack starting end is at an intermediate position between the first and second ends of the metal member and is between the pair of beam portions, a changeable load member having an expansible chamber disposed between the beam portion around the first end of the metal member and a means for supplying pressurized fluid to the expansible chamber. The changeable load member applies a load to the crack growth portion and the means for supplying pressurized fluid to the expansible chamber is responsible for ensuring that the displacement of the beam portions is accomplished in such a manner so as to provide a constant stress intensity factor at a crack growing point.

Abstract: A gripping system for use in uniaxial testing of test specimens at elevated temperatures, typically above 900.degree.-1000.degree. F. The uniaxial mechanical testing is typically tensile testing conducted on high temperature engineering materials which operate under severe conditions at elevated temperatures. The gripping system includes a gripping element having a first section adapted to contact the test specimen wherein a heater is received in the second section for heating the gripping surface. The heater is designed to heat the gripping surface and the test specimen to the desired temperature.

Abstract: The ultimate tensile strength of a test sample is tested in a high speed testing machine having a frame (2), a force measuring device (9A), and a load application mechanism (3, 4) for applying a loading stroke to the test sample after a loading piston has passed through a lead stroke to attain the required testing velocity. A force locking, frictionally effective clamping mechanism clamps the test sample for coupling to the machine frame (2) and/or to the load application mechanism (3) when the loading piston has reached the testing velocity.

Abstract: A corrosive environment sensor comprises an elongate member having a pair of elongate beam portions and a crack growth portion formed between the pair of beam portions so as to extend axially, and a wedge inserted between the pair of beam portions, wherein the crack growth portion has width thereof defined by quadratic curves extending axially so as to decrease from an axially intermediate portion of the sensor member to an axially intermediate portion of the crack growth portion and increase from the axially intermediate portion of the crack growth portion toward an end of the sensor member. The quadratic curves each consist of a first circular arc with first radius between the axially intermediate portion of the sensor member and the axially intermediate portion of the crack growth portion and a second circular arc with second radius less than the first radius between the axially intermediate portion of the crack growth portion and around the second end of the sensor member.

Abstract: A test piece subjected to a test is embodied from a pellet in which two half-moon shaped notches are embodied, the test piece taking support on two arc-shaped shoulders situated at the base of a clamping jaw extremity having a ribbed support plate. Two jaw extremities are disposed into a female clamping jaw of the test equipment. The present invention provides elements for measuring the residual resistance of a test piece following an atmospheric re-entry.

Abstract: The present invention describes an improved collet grip for holding tensile bars during testing. The collet includes a 90.degree. concave surface to match the machined tensile bar thereby improving the gripping action. The collet also has a taper on the inside diameter to compensate for any allowable taper in the machining process.

Abstract: Test samples, especially samples made of ceramic materials, are tested under tension and/or compression loads while simultaneously avoiding the application of a bending moment to the test sample. For this purpose, each end of the test sample is held by a holding element having spherical outer surfaces received in spherical segment recesses of clamping jaws. Each test sample end is held by its holding element in a form-locking force-transmitting manner without a direct contact between the clamping jaws and the test sample. The application of bending moments to the test sample is avoided because the cooperating spherical surfaces permit an adjustment of the testing sample into a vertical position without any canting of the test sample.

Abstract: In accordance with the present invention an improved alignment assembly is provided wherein when a threaded fastener is the test specimen, the fastener is gripped by a collet made of two longitudinally split, threaded, and tapered pieces held together with a spring. As a load is applied to the specimen, the two collet pieces are locked together by the tapers, assuring thread alignment. The split collar also preferably has different threads per inch at each end of the collet pieces to adapt to different threads of different specimens. Split collars of different geometry are used to test thin, non-threaded specimens. In a preferred embodiment, a reversible washer in which a first face is used to hold the fastener in place and in alignment in a first test, is also used to test the elongation of the fastener in a separate test, through the use of a second tapered face.

Abstract: Improvements in test specimen grip apparatus for tensile stress testing machines includes replaceable grip inserts that are able to accommodate wider than usual test specimens, particularly textile test specimens. The specimen grip means or grip inserts are threadedly retained on and may be substantially wider than their supporting jaw members. The grip housing, moreover, is provided with apertures for access to the threaded retainers for ease of grip insert removal and replacement. In addition, fluid actuation is preferably provided for the jaw members of the improved grip apparatus and a thumb screw is also disclosed for temporarily locking the jaw members in a selected open position, when mounting test specimens or removing and/or replacing grip inserts.

Abstract: A stabilization and gripping device for use with a compression test machine to measure strain vs load characteristics of, in particular composite material uni-directional ply specimens, includes a guide sleeve, two hollow open ended end-blocks adapted to slidably fit within the guide sleeve and to co-operate with parts of the machine for applying compressive forces to the specimen, and two pairs of collets each pair for gripping a separate one of two ends of the specimen, the collets having a planar gripping inner surface, at least one outer surface tapered with respect to the gripping surface and corresponding to a tapered inner surface of the end blocks, and a planar outer surface for co-operation with a substantially planar inner surface of the end blocks so that the collets may be non-rotatably inserted in the end blocks in a position in which the respective inner surfaces are parallel and pairs of the inner surfaces define a location for the specimen ends.

Abstract: A grip for a material testing load frame including a grip plate for engaging the end of an elongated sample having a longitudinal axis and a grip body having one end for connecting to the grip plate and another end for connecting to a loading component of the frame, a mechanism for adjusting the concentricity of the plate with respect to the body, and a mechanism for adjusting the angle of the plate with respect to the body, so that when the sample end is engaged by the plate, and the grip body is connected to the loading component, the longitudinal axis and the axis of the loading component can be aligned with respect to the concentricity and angle.

Abstract: Grip apparatus for use with tensile stress testing apparatus includes a housing having connecting means on the top of the housing for connecting the grip apparatus to the tensile stress testing apparatus. A first elongated bore extends from the bottom of the housing through a portion of the housing parallel to the longitudinal axis of the housing to form a receptacle for a test piece. A pair of second elongated bores extend from the top surface of the housing, converging toward the bottom surface of the housing, with the lower end of each second bore opening into the first bore. Each of said second bores contains a slidable grip bar extending into the first bore and having a grip insert secured on the lower end of the grip bar. A spring loaded release mechanism normally retains the grip bars and grip inserts in a closed position and can be manually operated to release the inserts and grip bars by sliding the grip bars upwardly through the second bores.

Abstract: A lumber testing apparatus incorporates opposed wedges to simultaneously exert tension and clamp forces on boards being tested. The inclined wedge surfaces utilize bearing materials and wedge angles selected to match the required clamp forces to tension forces on each board, without crushing the boards at high loads. This is accomplished by using bearing materials having a variable coefficient of friction under varying load conditions.

Abstract: The present invention is directed to an apparatus and method for holding one or more test electrodes of precisely known exposed surface area. The present invention is particularly useful in a device for determining the corrosion properties of the materials from which the test electrodes have been formed. The present invention relates to a device and method for holding the described electrodes wherein the exposed surface area of the electrodes is only infinitesimally decreased. Further, in the present invention the exposed, electrically conductive surface area of the contact devices is small relative to the test electrode surface area. The holder of the present invention conveniently comprises a device for contacting and engaging each test electrode at two point contacts infinitesimally small in relation to the exposed surface area of the electrodes.

Abstract: Hydraulically actuated grips are constructed to permit loading of specimens from either side of the grips. The grips are particularly adapted for use with flat specimens, are easily actuated, and are symmetrically designed so that when actuated, the grips do not exert any substantial axial load on the specimen and a uniform clamping force is applied laterally across the specimen. In addition, the grips, which can be used for either tensile or compressive loading, do not exert any bending moment on the specimen during test loading.

Abstract: An assembly as used to test material in a specimen within a high temperat range. The specimen or workpiece is clamped into a clamping mechanism having two clamping heads that are movably disposed with respect to each other. A divided workpiece end holder is disposed within an inwardly enlarged opening form on the facing front walls of each clamping head. A measuring apparatus including two elongation measurement holders are disposed at two laterally displaced locations along the length of the workpiece or specimen. A shoulder configuration is located at the laterally displaced locations on the workpiece. As the specimen is pulled apart by the clamping mechanisms located at each end thereof, the material between the shoulders is elongated. A particular rod and tube arrangement is used to measure the relative movement occurring between the elongation measurement holders disposed at the shoulder locations on the workpiece.

Abstract: A pipe clamp suitable for transmitting a tensile force as well as a compression force to a pipe comprises a housing (18) having a cylindrical inner wall, an opening (19) for passing a pipe to be clamped, two guide blocks (21,22) each having a sliding surface (32,33) running obliquely with respect to the axis of the opening (19), and two clamping blocks (34,35) which may cooperate with the oblique sliding surface of the respective guide block. The axis of the cylindrical inner wall of the housing (18) and of the opening (19) are substantially perpendicular with respect to each other and the guide blocks (21,22) may be rotated over 180.degree.. By rotating the guide blocks the pipe clamp can be switched from the pulling condition to pressing and vice versa.

Abstract: A grip for a materials testing machine comprises a housing, first and second wedge members within the housing, the first wedge member having a gripping surface defining a test-specimen-receiving aperture and the second wedge member having an aperture for receiving the first wedge member, the wedge members being movable with respect to each other, and each of the wedge members having an inclined portion directed oppositely to the inclined portion of the other wedge member, and means for preloading the wedge members to cause them to move with respect to each other, whereby the wedge members interact to exert a gripping force on a test specimen through the first wedge member's gripping surface.

Abstract: Grip apparatus for use with tensile stress testing apparatus includes a housing having connecting means on the top of the housing for connecting the grip apparatus to the tensile stress testing apparatus. A first elongated bore extends from the bottom of the housing through a portion of the housing parallel to the longitudinal axis of the housing to form a receptacle for a test piece. A pair of second elongated bores extend from the top surface of the housing, converging toward the bottom surface of the housing, with the lower end of each second bore opening into the first bore. Each of said second bores contains a slidable grip bar extending into the first bore and having a grip insert secured on the lower end of the grip bar. A spring loaded release mechanism normally retains the grip bars and grip inserts in a closed position and can be manually operated to release the inserts and grip bars by sliding the grip bars upwardly through the second bores.