Overall Stability Calculation And Program Development Of Offshore Mobile Platform

Improving the ability of exploiting resources in ocean is one of the most important content to implement the strategy of building a maritime power.Offshore platforms are the main equipments which exploit offshore oil and gas resources.China has made great progress in the field of marine engineering equipments and products have a certain position in the international market.But their overall technical level is not high,especially the ability of preliminary design is not strong and there is a certain gap between the advanced countries.We must increase R&D investment to enhance competitiveness.Mobile platforms have special advantages when exploiting resources in the open sea and deep water.For the complexity of the working environment,the stability and ability to survive a hostile sea environment are important considerations in the design.Self-elevation platform and semi-submersible are two main types of offshore platforms,their overall stabilities include intact stability and damaged stability which are closely related to the safety of the platforms.The present paper has studied the common requirements to the stability of platforms in domestic and foreign rules in detail,and analyzed the external load conditions that affect stability.In order to improve stability demonstration efficiency in preliminary design and save design cost,based on stability calculation methods for conventional ships,I have summarized the theory system of stability evaluation for the mobile platforms and a set of general calculation standards for wind load,hydrostatic factors,floating condition and overall stability.Then I have used programming language to build computational models which are divided into modules.The program has the functions of modeling,calculation,output and so on.It has proved the program is correct by checking used numerical values of an engineering example.On this basis the program has been upgraded includeredeveloping human-computer interaction interface,adding automatic data reading and graphic output ability and developing a calculation program for freeboard separately as a supplement for checking stability.Practice shows that the program has great practical value,and will be great potentiality by further improving and upgrading,so it is worth continuing R & D investment.