FEATURES OF THE ELEMENTS OF THE STEEL ENLARGING FRAME FOR THE TRANSPORTATION OF THE OFFSHORE STEEL PLATFORM

Abstract

One of the key regions of oil and gas production growth in the near future for the Russian oil industry is the Northern Caspian. The Caspian Sea shelf is being developed by JSC "Lukoil". The largest of the explored in Russia over the past 20 years, the V. Filanovsky field, it contains the main recoverable oil reserves. A complex of hydraulic structures is being built for the development of the V. Filanovsky field, and one of these structures of the complex is an ice-resistant offshore platform.

Subject of research: The support blocks and the steel deck of the offshore stationary platform are manufactured and equipped at the ship repair plant. To deliver such large-sized and heavy blocks of the offshore platform to the installation site in the sea, a steel enlarging frame is required. The steel enlarging frame is a complex spatial rod engineering structure. The operation of elements and nodes has been little studied and requires clarification.

Materials and methods: The LIRA CAD software package allows you to get a picture of the stress distribution in the elements of rod metal structures. To study the stress-strain state of the elements of the steel enlarging frame and their coupling nodes, two finite element models have been developed taking into account special loads at various stages of transportation.

Results: As a result of studies of static and dynamic effects from external loads, deformed and strength schemes with information about the elements of the steel frame were obtained. According to the results of the analysis of strength calculations, the following data were obtained: - with the load "excitement" up and down on the right, "efforts decrease by 1%; - with the load "excitement", twisting to the left counterclockwise," efforts decrease by 11-20%; - the device of vertical truss belts (VF) in the form of a composite H-shaped profile made of high-strength steel reduces the material consumption by up to 5% compared to alternative sections; the device of a VF lattice of tubular cross-section and connecting elements made of high-strength steel reduces the material consumption by up to 25% for lattice elements and up to 10% for connecting elements.

Conclusions: The steel enlarging frame, which connects the supporting blocks of the offshore steel platform, must be designed in the form of a spatial rod beam consisting of vertical trusses of rectangular shape, with struts in the support panels and a system of vertical and horizontal connections.