Development of branch drilling with waterJets for sub-sea floor Methane hydrate

本文提出了一种带有叶片泵的自旋式水射流喷嘴系统，并研制了喷嘴系统样机。为了阐明喷管系统转速的基本原理，对喷管系统的转速进行了测量。结果表明，采用叶片泵式制动系统的喷嘴系统获得的喷嘴系统转速远小于不带制动系统的喷嘴系统的转速。

In this study, a self-spin waterjet nozzle system that has a vane pump for braking rotational speed of nozzle system was proposed, and a prototype of a nozzle system was developed. To clarify the fundamentals on the rotational speed of the nozzle system, a measurement of the rotational speed of nozzle system was conducted. It was clarified that the rotational speed of nozzle system obtained for the nozzle system with the vane-pump type brake system was much smaller than that obtained for the nozzle system without the brake system.