Traditional rock cutting, coring, and metal cutting methods have serious technical, environmental, and safety limitations for underwater applications. High-pressure abrasive-waterjet (AWJ) cutting is currently being demonstrated as a revolutionary technique for cutting any material at ocean depths up to 20,000 feet. This method is marginal in performance and operational reliability, however, and further improvements are not expected. This research addresses a novel concept for cutting with high- velocity abrasive particle beams. In this concept, the abrasives are directly pumped through a nozzle, rather than entrained as in an AWJ nozzle, to form a high-pressure abrasive slurry jet (ASJ). QUEST demonstrated that cutting rates (under atmospheric conditions) can be increased fivefold compared to an AWJ using this new method. In this research we will conduct a feasibility study on using ASJs for underwater cutting. A high-pressure (50,000 psi) abrasive slurry pump under development at QUEST will be used in this investigation. Parametric cutting tests will be performed on rocks and metals. Analytical studies will be used to support the experimental work. A conceptual design for an ocean floor cutting system will be prepared.
