METHOD OF DISCRIMINATING DEFECTIVE OR NONDEFECTIVE CUTTING IN METHOD OF ABRASIVE JET CUTTING CONSTRUCTION

摘要

PURPOSE: To discriminate it at a time when a cutting state becomes inferior by detecting a vibration level of a material to be cut by a vibration pickup arranged in a prescribed position of the material to be cut in cutting and by discriminating whether or not it is in the perfect cutting state based on the detection signal. CONSTITUTION: A material B to be cut such as a steel pipe, a Hume pipe, etc., in the underground or underwater is cut by a jet flow from a jet nodule 6 in the prescribed direction. In cutting, the vibration level of the material B to be cut is detected by a vibration pickup 11 arranged in a prescribed position of the material B to be cut. This detection result is compared with one or both of the high frequency level value in perfect cutting and the low vibration level value in uncutting in a discrimination part 12 so that, whether it is at present in the perfect cutting or uncutting state is discriminated. As a result, when it is the perfect cutting, a blue lamp of the information part is lit, while being the imperfect cutting, a red lamp is lit and at the same time, an alarm is sounded so as to inform it to an operator at real time.