A method for testing a helmet for effectiveness of user protection includes moving a load along a predetermined path, supporting a target body at an impact location in the predetermined path, the target body including a head model and a helmet disposed on the head model, and impacting the target body with a force generated by the moving of the load. The impacting of the target body entails contacting the target body with an impactor free to move perpendicularly and tangentially relative to a surface of the target body. The supporting of the target body is at least reduced, if not eliminated, before or during the impact of the impactor with the target body at the location. Forces generated are automatically measured or sensed during the impact of the impactor with the target body at the location.

A destructive inspection method of a vitreous silica crucible for pulling a silicon single crystal evaluates a crack state of an inner surface of the vitreous silica crucible supported by a graphite susceptor when a load is instantaneously applied to at least one point on the inner surface via an automatic center punch while pushing the tip portion of the automatic center punch against the inner surface. The destructive inspection method can inspect the vitreous silica crucible under conditions as close to the actual conditions of use as possible.

The present invention is directed to an automatic impact inducing device for inducing an impact on an object wherein, in particular on a machine tool.

An exemplary crash gate to guard against motor vehicles crossing a roadway in a direction from an attack side to a protected side including a buttress post assembly secured below ground in a first concrete foundation on a side of the roadway, the buttress post assembly having two buttress posts forming a barrier passage, a latch post assembly secured below the ground in a second concrete foundation on an opposite side of the roadway, the latch post assembly having two latch posts forming a latch gap, a barrier with a gate beam disposed in the barrier passage and extending from a buttress end to a latch end, and one of a vertical pin or a hook connected to the latch post assembly and positioned in the latch gap and the other one of the vertical pin or the hook located on the latch end, when the barrier is in a closed position the latch end is located in the latch gap and the vertical pin is positioned outside of the hook.

A system for evaluating a bond includes a first electrode and a second electrode that are spaced apart from one another. The system also includes a sacrificial material layer positioned proximate to a surface of a bonded structure that includes the bond. The system also includes a power source configured to cause the first and second electrodes to generate an electrical arc that at least partially ablates the sacrificial material layer as part of a non-destructive inspection of the bond.

The method for evaluating the compactness of a layer of railroad ballast near a railroad tie includes at least one step of taking at least two measurements (11,11a,11b) of the penetration resistance (Qd) of the ballast (13) near one and the same railroad tie (10), and a step of calculating the mean value (Qd.sub.mean) of these measurements (11,11a,11b) of penetration resistance (Qd). Also provided are a device for implementing such a method and a method for predicting the settlement of the ballast of a railroad track including a step of evaluating the compactness of a ballast near a railroad tie.

This disclosure provides methods of predicting the steady state small scale critical temperatures (S4 T.sub.c) of polymer resins and pipes therefrom.

A pre-tension and tensile impact test apparatus capable of simulating a full-sea-depth environment includes a pre-tensioning device, a Hopkinson bar device, a seawater pressure simulation device, a power source group and an acquisition control unit. The Hopkinson bar device includes an input rod, an air compressing device, a test sample and an output rod. The pre-tensioning device, the input rod, the air compressing device, the seawater pressure simulation device, the test sample and the output rod are successively arranged on the same axis. The air compressing device includes an air cylinder, an end cover and an impact piston. Two ends of the air cylinder are each provided with the end cover. The impact piston and the air cylinder are in clearance fit. The input rod is coaxially connected to the impact piston. Two ends of the input rod each extend out of the end cover.

A handheld quality inspection tool for projection welded components and method for utilizing the same is disclosed. The handheld quality inspection tool includes an elongated hollow tube, a spring support, a spring member, a plunger, and a handle. The elongated hollow tube defines a slot. The spring support is connected to an end portion of the elongated tube. The spring member is disposed within the elongated hollow tube and connected to the spring support. The plunger is disposed in the elongated hollow tube and connected to the spring member opposite the spring support. The handle is connected to the plunger and protrudes from the elongated hollow tube through the slot and is translatable along the slot to move the plunger and compress the spring member. Upon release of the handle, the compressed spring member propels the plunger to apply an impact force to a projection welded component.

The present disclosure relates to an apparatus and a method for an impact test, which can easily accelerate an impact body at a desired acceleration using an air pressure and an electromagnetic force. According to an embodiment of the present disclosure, an apparatus for an impact test includes a clamping unit configured to fix a specimen, and an impact unit disposed to be spaced apart from the clamping unit and configured to accelerate and launch an impact body to collide with the specimen by an air pressure and an electromagnetic force.