Disclosed is a system capable of simultaneously performing a thermal test, an electrical test, and a mechanical test in an environment similar to the installation environment of a dynamic cable. The system includes a seawater tank module configured to form a seawater environment for a test cable, a mechanical test module configured to perform mechanical aging of the test cable according to an actuator operation, an electrical test module configured to perform electrical aging of the test cable by applying a voltage to each of opposite ends of the test cable, a thermal test module configured to perform thermal aging by applying a current to a dummy cable formed independently of the test cable, and a control module configured to perform data input, control processing, monitoring, and storage of the seawater tank module, the mechanical test module, the thermal test module, and the electrical test module.

Analysis method for minimum necking deformation cross-section center stress and strain comprising: recording values for axial acting force, minimum cross-section radius, maximum limit of cross-section radius, inflection point position tangent slope of a rotational generatrix of a contour, radius of cross-section perpendicular to central axis at the inflection point position, and distance between the cross-section perpendicular to the central axis at the inflection point position and minimum cross-section at a necking bottom; and establishing a rectangular coordinate system by taking a center position of the minimum cross-section at the necking bottom as an origin, and substituting the recorded values into mathematical models of a first, second, and third principal stress at a center position of the minimum cross-section to calculate and obtain three principal stress values at the center position of the minimum cross-section, e.g., to calculate stress components, equivalent stresses (Mises), stress invariants, and equivalent plastic strain.

A method and detectors detect arrow shaft weak spines. A plurality of arrow shafts are positioned about a central axis and compressed in a direction along the central axis to concurrently bend each of the arrow shafts. The plurality of arrow shafts are individually rotated, while compressed, such that each of the plurality of arrow shaft bend the same direction. Each of the plurality arrow shafts is marked based on the bending. In some implementations the detectors comprise a shaft retainer having a spherical surface that engages another spherical surface.

One example of the present disclosure relates to a coupon. The coupon includes a first surface with a first circular channel and a second surface opposite and parallel to the first surface. The second surface is spaced a distance D0 from the first surface and includes a second circular channel concentric with the first circular channel. The coupon also includes a toroidal portion between the first circular channel and the second circular channel. The toroidal portion includes a rectangular sectional portion.

A concrete test cylinder mold formed of expandable polystyrene and which is used to form geometrically uniform concrete test cylinders that accurately reflect the structural properties of the concrete mix used to form the test cylinders despite fluctuations in temperature to which the test cylinder may be exposed during formation within the mold. The mold is constructed and configured such that compression testing of the concrete test cylinder may be conducted while the cylinder is still in the mold. A specially designed heat shield may be used in unison with the concrete test mold to form, at least in part, a system by which heat further may be retained within the system during formation of the concrete test cylinder.

A concrete test cylinder mold formed of expandable polystyrene and which is used to form geometrically uniform concrete test cylinders that accurately reflect the structural properties of the concrete mix used to form the test cylinders despite fluctuations in temperature to which the test cylinder may be exposed during formation within the mold. The mold is constructed and configured such that compression testing of the concrete test cylinder may be conducted while the cylinder is still in the mold. A specially designed heat shield may be used in unison with the concrete test mold to form, at least in part, a system by which heat further may be retained within the system during formation of the concrete test cylinder.

A breaking strength tester includes: a tubular pressure container having opened both ends to house a part of a pillar-shaped honeycomb structure including a partition walls and a circumferential wall; a tubular pressurization elastic body disposed to surround an entire circumference of a pressurized portion having a length equal to or less than of a length in an axial direction of the circumferential wall; a partial pressurization unit which elastically deforms the pressurization elastic body and applies uniform pressure to the entire circumference of the circumferential wall of the pressurized portion of the honeycomb structure housed in the pressure container up to pressure test strength; and a pressure measurement unit which measures a value of the uniform pressure applied to the circumferential wall by the pressurization elastic body.

Resonance test machine for vibration strength testing of a test body which is clamped between a cross member and a vibration head. The vibration head, test body and cross member are part of a second sub-oscillatory system which is vibratable in an axis x, in which the test body and a resonator containing the vibration head, a vibration spring and a vibration body are arranged successively in series along the x axis. A first sub-oscillatory system, which is also vibratable in axis x, is present in series to the second sub-oscillatory system and the resonator, wherein the first sub-oscillatory system contains the vibration body, spring elements, a seismic mass and electromagnetic vibration exciters.

A method for detecting degradation of resin film detects whether a resin coated rope having a circumferential portion coated with resin film has the resin film degraded. The method for detecting degradation of resin film includes: winding a wire on a circumferential portion of the resin coated rope; applying tension to the wire to compress the resin film in a radial direction of the resin coated rope; and comparing a first relationship with a second relationship to determine how the resin film is degraded, the first relationship indicating a relationship between the tension of the wire and how much amount the resin film has compressed, as obtained in the applying, the second relationship indicating a relationship between the tension of the wire and how much amount the resin film has compressed, as predetermined as a reference.

Apparatus and methods related to umbilical bend-testing are described. For example, some embodiments may contain a three-level support structure, umbilical terminal locker, bending machine, compression testing device, and stress-strain collection system, and may be used for the bending fatigue endurance test for umbilical samples.