Design Of Semi-active Heave Compensation System For Hydraulic Drawworks

Deep-sea oil production generally adopt floating drilling ship and semi-submersibledrilling platform，Platform can produce periodical heave movement with the movement ofwaves，Hook on the platform drives the drill string to move together with it，It will result inchanges of bit weight，and it will affect the service life of drill bit，it may even be forced toshutdown，these will lead to increase of the drilling cost. Therefore, installing the heavecompensation system in the ocean drilling platform is crucial to compensate the displacementof hook.At present，commonly used heave compensation system on the platform is the travelingblock compensation system and the crown block compensation system, But the traditionalcompensation system all requires special compensation devices, weight and volume is verylarge, it is very bad for very precious offshore platform. This article analyzes the traditionalheave compensation system, and puts forward the concept of semi active heave compensationsystem of the hydraulic winch.Drilling winch is the necessary lifting equipment of platform, Winch heavecompensation system need not add extra compensation devices, Use hydraulic pump andaccumulator to drive compensation system commonly, finally realize half activecompensation. This way of compensation saves space and reduces the weight of the platformwhich needs to bear. Because the compensation winch power is very large, and the standardwinch has not heave compensation effect, we can’t choose winch according to the standard.This article uses Matlab programming calculation to design and calculate structureparameter of compensation winch and hydraulic system，and configured the power ofcompensation system. On the basis of analyzing the working principle of the hydraulic circuit,designed the hydraulic circuits, and had carried on the selection of main components of hydraulic system.In order to study the compensation effect of compensation system, I made mathematicalmodeling for passive compensation system and the semi-active compensation system, andcompensation system was simulated by using the Simulink software, synthetically consideredthe energy saving and compensation effect of the compensation system, Got the right cylindervolume, and studied the compensation effect of the compensation system in different seacondition.