Abstract

Agile activated circulation sub is presented, with design advantage of being able to open and close numerous times and there is no limitation to the number of tools run in the string. The tools now being field tested are designed to perform complete needed cycles in one trip, with the total number of cycles limited only by the battery life.

The standalone tool system activated by sensing its environment (Flow, Pressure or RPM), working internal logics before being in a position to receive surface signal to operate in desired mode. The tool has application in any well where it operates the first position for partial bottom-hole-assembly (BHA) bypass increasing annular flow and second, full bypass, position for dumping lost-circulation-materials (LCM) or fast wellbore clean up, the final, downhole barrier isolate drill string above the tool from downhole pressure in well control situation.

Restrictive BHA limits the flow rate and annular velocity required to clean the hole during drilling or displacement operations. BHA restrictions can also limit the size and concentration of LCM and wellbore strengthening material needed to seal troublesome zones. The tool helps driller reduce risks associated with hole cleaning by improving annular fluid velocity with the ability of running multiple tools in same BHA in hole cleaning mode. Each tool can be operated independent of all other tools, allowing driller to optimize hole cleaning hydraulics, as well, tools can be configured with suitable side port nozzle to achieve the desired pressure drop and flow split according to well program. The tool presents advantages over the industry's current system is that there are no restricting ball seats, flow chokes or ball catcher subs in the tool. This paper presents the design, engineering, testing, field trial results, application and function of this new circulation valve

The novelty of the tool is in the ability provided for driller to overcome circulating challenges efficiently and effectively irrespective of tool depth or well profile in reasonable time using variation of RPM, or variation of flow rate. When circulation is not possible or when string is stuck, the tool can be operated to assist driller resume circulation using pump pressure without need for flow.

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