Apparatus and method for utilizing reflected waves in a fluid to induce vibrations downhole

• Main Author: William A Hered
• Format: Patent
• Language: English
• Published: 19.05.2021
• Subjects: EARTH DRILLING; EARTH DRILLING, e.g. DEEP DRILLING; FIXED CONSTRUCTIONS; MINING; OBTAINING OIL, GAS, WATER, SOLUBLE OR MELTABLE MATERIALS OR ASLURRY OF MINERALS FROM WELLS

In one aspect, an apparatus for inducing vibrations in an object in a wellbore is disclosed that in one embodiment includes a tubular conveyable in the wellbore and has at its bottom end an engagement tool that is configured to engage with or latch onto the object. A first flow control device, such as a cycling valve, in the tubular cycles (closes and opens) at a selected frequency or rate and generates at each closing a first upward pressure pulse in a fluid flowing through the tubular and a downward pressure pulse in the fluid, which induces a first force in the engagement tool and thus in the fish engaged with the engagement tool. A second flow control device, above the first flow control device in the tubular, closes in response to the first upward pressure pulse during each cycle and generates a second upward pressure pulse in the fluid flowing through the tubular and a second downward pressure in the fluid and a corresponding second force in the object. The selected frequency may be set to match a resonant frequency of the tubular. The first flow control device may be cycled to close on or before arrival of the second downward pulse at the first flow control device to generate a resonance in the tubular.