METHOD FOR MEASURING THE LENGTH OF A PIPE STRING DURING HOISTING OPERATIONS Russian patent published in 2020 - IPC E21B19/00 G01B11/26 G01C3/00 

FIELD: oil and gas industry.

SUBSTANCE: invention relates to oil and gas industry and can be used for determination of pipe string length by optical methods. Method includes measurement of each pipe and addition of lengths of each of pipes by means of controller, recording length of each pipe. To measure the length of the pipe on the mast of the lifting mechanism, a laser length meter is fixed so that at the vertical position of the lifted pipe the beam of the long-length laser passes inside it along the whole length. Each pipe is equipped from below with a protective cap with material reflecting laser beam inside during measurement, at that, hoist block of pull-lifting mechanism is equipped with electromagnetic starter including length meter at vertical location of the measured pipe. Prior to each setting of hoisting mechanism, control measurements and calibration of controller are performed to obtain maximum accurate results. After measurement of pipe length protective cap is removed before its connection with column of already run-down pipes and / or lowering into well.

EFFECT: design of a method of measuring length of pipes at lifting-lifting operations, which simplifies use due to application for measurements of laser length meter and independent of external factors.

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