SELECTION OF PARAMETERS AND BENDING VIBRATIONS OF DEEPWATER DRILLING ALUMINIUM RISER IN RANDOM WAVES

摘要

Application of aluminium risers for drilling boreholes in deep sea makes it possible to decrease cost of their production and operation. The paper discusses issues of deepwater aluminium riser parameter selection and studies its dynamic characteristics: slope from the vertical and bending stress during exposure to random waves and surge of the drilling vessel. Dynamic analysis is carried out in spectral form using the method of statistical linearization. Numerical calculation of the riser dynamics involves asymptotical method with possibility of its effective use rigorously substantiated. On the basis of the proposed numerical method, program RIBERA has been developed for the calculation of deepwater riser dynamics. Analysis of the aluminium riser for drilling at sea depths of 2700 and 4000 m has shown that this riser meets the requirements imposed by API recommendations.