Disclosed example apparatus to align a test specimen in a universal testing system include: a first specimen grip configured to be attached to a universal testing system, to hold a test specimen in a first orientation with respect to the universal testing system, and to move the test specimen toward a test axis of the universal testing system; and a specimen stop configured to be attached to the universal testing system and to set a stop point of the test specimen, the first specimen grip and the specimen stop configured to align the test specimen with the test axis.

Disclosed example grip assemblies, such as for holding a sample for testing in a material testing machine, include: a core member extending along a central axis from a first end portion, configured to releasably mount the grip assembly to a crosshead, to a second end portion, wherein the core member comprises a body portion having a pneumatic cylinder enclosing a pneumatic volume; a pneumatic piston head arranged to be slidably received in the pneumatic cylinder and to be moveable along the pneumatic cylinder in a first direction to expand the pneumatic volume, and in a second, opposing, direction to contract the pneumatic volume; a housing, including a sleeve member coaxially mounted around the body potion; a sample holder disposed at the second end portion, configured to selectively apply a holding force to a sample for testing; and a driving member configured to contactingly engaging the sample holder.

The present disclosure relates to an electronic control system for pneumatic grips, using proportional air pressure control, as employed in the field of materials testing. The disclosed embodiments allow for variable gripping pressure thereby increasing the safety for the user/operator. Additionally, materials testing will not commence until the proper pressure for testing has been achieved.

The present invention relates to a holder having an actuation unit, particularly as a part of a material testing machine for testing specimens, for example metal test-specimens, which are held at high forces that are particularly due to the type of testing. The actuation unit operates with pressure from a pressure source. A bi-stable fluid control valve is temporarily in a first or in a second state, in particular depending on pressures at actuation sides of the valve. Besides a first actuator, which is responsible for the regular clamping force of the clamping face, to a second actuator is provided. The second actuator may also be referred to as motion unit due to its motion force to the clamping piston. The actuators arrange for a certain de-coupling of the different forces when holding and clamping specimens. Such a circuit offers the desired safety degree.

A system for testing or calibrating a part, the system including: a plurality of test stations, each test station including a container and a clamping mechanism, wherein the clamping mechanism includes: a clamp frame including: two clamp plates; a plurality of clamp bars configured to securely hold the clamp plates at a distance relative to each other; a seal manifold provided on one of the two clamp plates; and a clamping module, located opposite the seal manifold on another of the two clamp plates, wherein the clamping module includes: a plurality of pistons to hold the part against the seal manifold for the test operation; and at least one cleaning station comprising a spin mechanism for spinning the part to remove excess fluid; and a robotic system for moving individual parts to and from the plurality of test stations and to and from the at least one cleaning station.

A wide-temperature-range uniaxial and biaxial compression test device in a high-pressure hydrogen environment is provided. An upper computer is interacted with a temperature sensor, a gas pressure sensor, test pressure sensors, displacement sensors, an oxygen/hydrogen concentration monitor, a hydrogen filling system, a vacuum extraction system, a DIC test system, and the other components. The upper computer is used to achieve high-pressure hydrogen environment wide-temperature-range uniaxial and biaxial compression test based on different test modes. Tested engineering stress-strain data is processed to obtain real stress-strain data of rubber, and then the real stress-strain data is processed through a corresponding database to screen out a constitutive model capable of best characterizing the nonlinearity of the rubber specimen. Meanwhile, a strain distribution nephogram generated by a test result of a sample material can be analyzed, thus obtaining a deformation behavior and a failure fracture mechanism of the sample material.

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.

A device for fixing a rock sample, including: a lower clamp and an upper clamp; the lower clamp including a lower connector connected to a loading base at a bottom of a testing machine, a lower end cap for fixing samples, a lower chain connecting the lower connector and the lower end cap, a first spiral spring, a first central position-limit mechanism, a second central position-limit mechanism, and a first hydraulic mechanism; the upper clamp including an upper connector connected to a loading base at a top of the testing machine, an upper end cap for fixing samples, an upper chain connecting the upper connector and the upper end cap, a second spiral spring, a third central position-limit mechanism, a fourth central position-limit mechanism, and a second hydraulic mechanism.

In a material testing machine including a load actuator including a shaft configured to make a linear motion, and configured to apply a load to a test piece through the linear motion of the shaft, the load actuator includes a bearing configured to support the shaft, and the bearing serves as an air bearing.

A heating and cooling device includes a conductive structure, an electric heating pipe and a housing. The housing has a main body and a test space formed in the main body, the electric heating pipe is attached on the main body and used for heating a testing plastic material in the test space, and the housing is covered outside the conductive structure and separated from the main body to form a cooling flow channel. The housing and the main body are separated without contacting each other, so that the dissipation of the heat energy of the electric heating pipe through the housing can be reduced in the heating process, and the function of thermal preservation can be provided. Moreover, the cooling effect can be improved through the larger cooling flow channel during the cooling process. A PVT equipment using the heating and cooling device is further provided.