METHOD OF MEASURING LENGTH AND DISPLACEMENT SPEED OF PIPE STRING WHILE ITS TRIPPING AND DEVICE FOR IMPLENETING THEREOF Russian patent published in 2008 - IPC E21B44/00 E21B19/00 

FIELD: mining.

SUBSTANCE: invention relates to means of measurement used in the field of drilling and wells operation and may find application in measuring the length and displacement speed of a pipe string while tripping, in particular, for detecting the drilling rate and location of a geophysical equipment being delivered to a survey interval by said pipe string. To this end a string of interconnected pipes is lowered into a well bore by a cable winch provided with a weight measuring device on its hoisting block, idle runs of said hoisting block are detected upon readings of the weight measuring device. Whereby a video camera registers the string displacement in time and space based on the displacement of a target attached to the cable winch hoisting block, said camera is capable to observe the upper and the lower position of the target in the course of the pipe string displacement, the target being alternatively placed in its upper and its lower positions. These positions are registered by said video camera and a produced displacement is measured in measures of length. Then coordinates of the tag centre in its upper and lower positions are found, and a numerical scale between displayed and real sizes is determined. A further measurement of the pipe string displacement is performed on the basis of the measurement of a displacement of the centre of the hoisting block tag on the display with allowance of the numerical scale, after each displacement the sum over all linear displacements is carried out taking into account the idle runs, and finely a current speed is calculated on the basis of the tag linear displacement per unit time.

EFFECT: creation of a method and a device for measuring the length and displacement speed of a pipe casing while tripping in the course of drilling.

2 cl, 2 dwg