Design of Turning Fixtures and Handling Frames for Cryogenic Vessel Components

Abstract

The cryogenic vessel is having diameter about 30 meters and weight of around 4000MT. Hence, it is not feasible to transport the entire vessel as a single unit. The assembly is divided into sub assembly of 54 modules, which need to be transported to installation site. It is required to design fixtures for effective transportation of these sub assemblies.

The purpose of the thesis is to design fixtures for handling plates and sectors during various stages of manufacturing, and cradles for transportation of modules to the site. The base frame of the cradles will have provision for mounting welding arrangements to assemble various sections.

Various schemes are conceptualized based on parameters such as welding process and sequence, fixture assembly planning, handling ease, shop floor height, crane capacity, fixture weight, on-road transportation limitation, etc. The fixtures are modeled using CAD software Solid edge ST2 and analysis is carried out using FEA software NX 7.5. The fixtures are investigated for structural analysis. By studying the results, the best possible design is selected.