Abstract: A tensile testing machine has a pair of cross heads relatively movable along an axis, each cross head having a mechanism for fixedly holding one end of an electrically conductive specimen and in at least one of said mechanisms, electrical insulating means electrically isolating the end of the specimen from the mechanism to provide for the specimen to be part of an electrical circuit for determining the time of specimen rupture.

Abstract: In order to determine the fatigue limit of elastic materials, especially rubber, under completely reversed stress by applying a load which alternates between zero and a maximum value and in order to determine the number of load alternations which leads to the breaking of the material, a plurality of strip-shaped rubber samples are clamped between two stationary clamping beams and a rocker. The rocker is approximately parallel to the beams and is moved at one end thereof by means of a crank mechanism. The rubber samples are each positioned parallel to one another in at least one row and are alternately stretched and relaxed to a different extent, depending on their spacing from the fulcrum of the rocker.

Abstract: A fastener tester for testing fasteners for securing a plurality of workpieces together with such fasteners including a pin member having an elongated shank with the fastener tester including a pair of relatively movable members adapted to have a fastener installed thereto and operatively associated with a load cell whereby installation loads and final clamp load or preload can be measured and subsequently the same fastener can be subjected to a tensile test and the resultant tensile loads measured.

Abstract: The present-day devices for automatic determination of the tensile strength properties of a sheet of paper are complicated, inconvenient to operate and incapable of producing immediate test results. According to the invention, the apparatus comprises two operating elements (6, 7) between which a sheet of paper of desired length is adapted to be introduced, the former operating element (6) comprising a fixing block (1) and a pulling block (2) and the latter operating element (7) comprising a fixing head (3) and a pulling head (4), said fixing head being compressible against the fixing block and said pulling head being compressible against the pulling block for fastening a sheet of paper. The other operating element is further fitted with a cutter means (8) which is adapted cut off a sheet of paper a sample of standard width as the sheet is positioned against the fixing block.

Abstract: A method and apparatus for determining the statistical distribution of apparent tensile strength of rock, the size effect with respect to tensile strength, as well as apparent deformation modulus of both intact and fractured or jointed rock. The method is carried out by inserting a plug of deformable material, such as rubber, in an opening of a specimen to be tested. The deformable material is loaded by an upper and lower platen until the specimen ruptures, whereafter the tensile strength is calculated based on the parameters of the test specimen and apparatus.

Abstract: The elongation of a rope or cable under impact stress is measured by attaching a light emitting diode (LED) to a free-falling weight which loads the rope upon impact. The LED is turned on in response to a drive signal indicative of stress of the rope of greater than a given value. The lit LED and an adjacent scale are photographed to provide a record of the distance through which the LED moves, when on, and this indicates the amount of elongation of the rope to failure.