KANTAN3 Offshore Derrick Safety Assessment Based On Vibration Tests

Offshore drilling derrick is an important component of offshore oil equipment.Through research and access to a lot of information at home and abroad,We know that the offshore drilling operations for the derrick is very different from on the land, Mainly due to bad weather at sea,changeable conditions,there is great impact for derrick suffering from work load and wind load etc,After prolonged use as well as the influence of factors such as environmental corrosion,Inevitably exist in one way or another defect,derrick structural changes have taken place in the physical characteristics,it does not possess the characteristics of the original design stage,This will seriously affect the derrick safety bearing capacity.At present,the safety assessment of the offshore derrick still at the exploratory stage,offshore derrick can not be carried out loading during the maintenance period,lack of necessary test data.How effectively to assess the carrying capacity of the offshore derrick with a simple and accurate method is very difficult.To an objective,accurate and comprehensive assessment of offshore derrick safety bearing capacity,based on KANTAN3 offshore derrick example,this paper presents the KANTAN3 offshore derrick safety assessment based on vibration tests. By vibration testing analysis,identified the dynamic parameters(natural frequencies,mode shapes etc),And correct the ideal finite element model with dynamic characteristic parameters,make the derrick model close to the actual structure,then assess the safety bearing capacity of KANTAN3 offshore derrick.This paper is closely integrated with projects,committed to resolve the current offshore derrick field problems that need urgent solution,there will be great significance in the formation and perfection of security assessment theories for the oil derrick based on vibration test.This paper is a part of Shanghai Offshore Oil Bureau KANTAN₃ offshore derrick safety assessment projects.