A new conceptual design of compact fatigue crack arresting device

Fatigue is the major cause of component or structure failure. A novel crack arresting gun providing free operating flexibility to repair/arrest the fatigue crack is designed. It can be automatically operated by PLC control with a robot arm. The nano-material is applied at a certain temperature lower than melting point on local areas of structure or component to repair the crack. The crack arresting gun includes body, handle, camera, nozzle and piston assembly. In this device, the laser is used as heating medium and a temperature sensor enables the material flow after achieving the required temperature. Laser light from a remote source flows through the nozzle central aperture to treat a workpiece. The nozzle central aperture may be surrounded by powder channel outlets aligned upon a working focal point incident after the laser beam. The workpiece is sprayed with powder after heated by laser beam. The shocking pressure may follow the material deposition process. A distance sensor may enable the process of repairing operation according to the presence and detection of a flaw. The crack arresting could be done simply by its compactness and simple mechanism. Conceptual design of the compact crack arresting device gives a high degree of freedom for operating to repair.