A method for testing thermal fatigue resistance of a shear cutter includes: engaging the shear cutter with a rotating target cylinder; moving the shear cutter along the rotating target cylinder until the shear cutter is heated to a threshold temperature; cooling the shear cutter in response to heating of the shear cutter to the threshold temperature; and repeating the heating and cooling of the shear cutter.

A method for checking at least one subregion of a component, in particular a component of a turbomachine, including at least the steps of a) providing a blank; b) producing at least the subregion from the blank by machining the blank using at least one tool and using at least one force sensor-to record at least one force curve of at least one force acting during machining on the at least one tool; c) checking whether there is at least one deviation-of the at least one force curve from at least one predetermined target curve-of the at least one force curve, the at least one deviation-characterizing at least one material defect-contained in an unmachined segment of the subregion. A checking device for checking at least a subregion of a component is also provided.

Analysis of residual stress in materials is often done in static conditions in a laboratory. Accurate systems and methods for performing these analyses in a dynamic, non-laboratory environment are notoriously difficult and can be very inaccurate. A method using a portable, field deployable apparatus having greater accuracy than currently available is disclosed whereby accurate and repeatable residual stress analysis may be implemented in non-laboratory environments leading to greatly improved diagnostics, maintenance and life limit prediction.

Analysis of residual stress in materials is often done in static conditions in a laboratory. Accurate systems and methods for performing these analyses in a dynamic, non-laboratory environment are notoriously difficult and can be very inaccurate. A method using a portable, field deployable apparatus having greater accuracy than currently available is disclosed whereby accurate and repeatable residual stress analysis may be implemented in non-laboratory environments leading to greatly improved diagnostics, maintenance and life limit prediction. Especially the analysis of a pipe or channel can be facilitated with this invention.

A method is provided. An actual fatigue curve limit is determined for actual stress of a drilling component based on an actual yield strength of a material of the drilling component. A plurality of drilling parameters is simulated for the drilling component to determine one or more estimated stresses enacted on the drilling component for one or more combinations of the plurality of drilling parameters. A component life cycle of the drilling component is determined based on the actual fatigue curve limit and the plurality of drilling parameters. A consumed component life of the drilling component is determined for an actual drilling step utilizing the drilling component, and a remaining life of the drilling component after the actual drilling step is determined.

The invention discloses a method for obtaining the geometrical and mechanical parameters of rock samples and a holographic scanning system thereof, wherein the system includes an observation mechanism, a multi-scale penetration mechanism, a grinding mechanism, a rock sample installation mechanism arranged on a three-axis precision motion platform, and an industrial computer controlling the operation mode of each mechanism of the platform Indentation/rotary penetration test, pulse echo signal acquisition, three-dimensional surface topography reconstruction, layer by layer grinding and repeated experiments are carried out. The geometric parameters and corresponding mechanical field parameters are obtained by spatial interpolation of the three-dimensional parameter lattice accumulated by several layers of single-layer rock parameters. The holographic scanning system and method can obtain the real spatial distribution of various media in rock samples. Combined with high performance numerical calculation method, it provides a more scientific method for the analysis of rock mechanical properties, failure and instability.

The shear head device includes a monitoring head having geophones and transmitters inside a cylindrical body. A shear head is coupled to the monitoring head from below. The shear head has a tubular structure with a plurality of apertures formed around an outer surface of the tubular structure. A plurality of cones are coupled with modified tips and disposed within the plurality of apertures. A sheet supports the plurality of cones inside the shear head. The sheet is selectively movable between a first radial position and a second radial position for the modified tips to apply radial force to the rock by adjustment of an internal pressure of the shear head. The transmitters transmit the recorded acoustic emission to a computing system for determining properties of the rock while the shear head device is testing the rock in the bore.

This patent studies a scale-span modeling method to simulate the structural mechanical responses and dynamic progressive failure behaviors of carbon fiber reinforced plastics (CFRPs) in drilling. Firstly, considering the different mechanical behaviors of fiber and matrix in micro state, a three-dimensional multi-scale dynamic progressive damage evolution model based on micro failure theory is proposed. Based on the degradation elastic parameters of microcomponent in typical volume element model, a new damage evolution model of fiber and resin matrix and an auxiliary deletion criterion of failure element are proposed. Secondly, the relationship between the macro stress and the micro stress of representative volume element in the composite model is established by using the stress amplification factor. Combined with the bilinear cohesion element model, the damage behavior of the composite in and between layers under the cutting action of dagger drill is simulated.

An apparatus for performing a contact mechanics test in a substrate includes a stylus having at least two contact elements. Each contact element has a contact profile, and the contact elements are disposed in the stylus to define a stretch passage therebetween. The stylus is configured to deform the substrate so as to cause the substrate to flow between the contact elements and induce tension in the substrate in order to generate and preserve micromodifications in the substrate. Methods of performing a contact mechanics test using the apparatus are also provided.

In one embodiment, a concrete strength testing system includes a core drill having a core barrel, a press associated with the core drill that is configured to drive the core barrel into concrete to be tested, a force sensor associated with the core drill that is configured to measure a force with which the core barrel is driven into the concrete by the press, and a depth measurement device configured to measure a depth into the concrete to which the core barrel is driven by the press.