STUDY OF THE DYNAMICS OF THE TRAVELING BLOCK-CROWN BLOCK MECHANISM OF THE DRILLING RIG WITH TWO ACTIVE DRAWWORKS

"In the hoisting equipment, the hoisting or lowering of the load at the hook is done with the drilling cable that connects the sheaves from the crown-block and those from the travelling-block. Failure of the drilling line can have catastrophic effects, hence it is very important to evaluate as accurately as possible the values of the lines tensions, so that during the drilling operations they do not exceed their tensile limits. The present paper deals with the study regarding the dynamics of the of the travelling block- crown block mechanism with two active drawworks and is establishing the expressions for calculation of the tensions from the drilling lines, depending on the load applied at the hook during both hoisting and lowering operations. The calculation is performed for the case of the travelling block-crown block mechanism provided with 3 respectively 4 sheaves and the values of the lines tensions for a hoisting equipment with two active drawworks are compared with the values for the conventional hoisting equipment. "