CAUSES FOR CRACK APPEARANCE IN THE WELDED JOINT OF THE SHIP WINCH FRAME DURING THE FAT TEST

Abstract

Sip winches are one of the most important parts of the ship equipment. They perform the most responsible tasks on different types of ships. Considering the responsibility of their tasks, ship winches must fulfill the strictest requirements in regards to functionality, reliability and working life span. Ship winches are in the majority of cases welded structures. In order for the high reliability requirements to be fulfilled, integrity of the welded joints of the winch's individual parts have to be investigated prior to their imbedding into the winch. After those tests are performed and the parts are built-in the winch, factory acceptance test (FAT) must be performed. During that type of tests almost all the flaws that can occur during production should be visible. In this paper is described an appearance of a crack in the ship winch frame that occurred during the FAT. The possible causes for such a crack to appear are discussed. In the closing, certain measures were proposed for reducing such cracks to a minimum. Some possible directions for future research oh this problem are proposed, as well.