The First Successful Domestic Test Performed by NGC Marine for PTI Clutch of Ocean Surveillance Ship Gearboxes

Nanjing High Accurate Marine Equipment Co., Ltd (NGC Marine) successfully performed benchmark testing for the soft engagement performance of the PTI clutch for the main propulsion gearbox of a large-sized ocean surveillance ship for the State Oceanic Administration (SOA) on April 25, 2014.

The marine main propulsion gearbox with PTI functions, characterized by its fuel savings, higher efficiency and higher navigation safety and reliability etc., can be used for free switching of motor or diesel engine as its power source, showing the advanced vessel propulsion mode. The PTI clutch is engaged at a rated speed (1500rpm for this project) and therefore the conditions are extremely severe. During the engagement, clutch disks can slip for a long period of time and lead to high temperature. This clutch is an important part for ensuring PTI functions. Considering the shock during clutch engagement, NGC Marine has developed 鈥淗ydraulic- electric鈥� control modules, realizing soft engagement and adjustable engagement time.

A high propeller rotary inertia and load under real ship simulations have been adopted for this test. Problems such as test benchmark capacity limits and high-speed data collection etc. have been solved by company management and technical support, and finally the test was successfully performed. During test, detailed dynamic data reading of soft engagement process have been collected; soft engagement functions of the PTI clutch have been verified effectively and out of which, important experiences have been accumulated for future projects with similar functions.

PTI function is currently an important developing direction for vessel propulsion systems. The successful testing has filled the gap in this particular technical field in China. NGC Marine has become the first propulsion manufacturer at home grasping the PTI soft engagement technology, providing powerful technical support for the domestic production of marine main propulsion equipment with similar functions.