Domestic Research on the Shark Jaw Device

YANG Song, WANG Huan, LIU Xiang, ZHANG Ming

（ Wuhan Marine Machinery Plant Co., Ltd., Wuhan 430084, China）

Abstract: Shark jaw device is one of the key equipment for modern engineering vessels to perform salvage, deep water anchor handing and offshore platform support operation. Its main function is to grip the anchor or mooring lines to prevent them from slippery. Shark jaw device works along with towing winch, crane, stern-roller and so on. Therefore, it can be divided into two forms of triplex shark jaw device and fork jaw device depending on their structure, And then the triplex shark jaw device can be further divided into the independent shark jaw device and the combined shark jaw device according to the location of shark jaw and towing pin. This paper gives an overview on the structures and research status quo of the shark jaw devices, points out the advantages of both the combined shark jaw device and independent shark jaw device applied to offshore vessels, summarizes the working principle of crank-rocker mechanism of triplex shark jaw device, elaborates the inclined and vertical towing pin structural forms, and explains in detail how to realize the towing pin rotary motion with both cylinder drive method and the geometry spacing method.

Key words: engineering vessel; shark jaw device; status quo