Experimental Device for Simulating Overflow and Lost Circulation in Deviated Wells
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The co-existence of overflow and lost circulation in fractured formations during deviated well drilling poses a significant challenge, as existing methods often fail to effectively address this complex issue, especially in formations with narrow pressure windows and multiple pressure systems, leading to safety concerns and inefficiencies in drilling operations.
Innovation Solution
An experimental device and method are developed, comprising a simulated deviated wellbore unit, a computer data processing system, a simulated formation fracture unit, a gas injection system, and a liquid injection system, which allow for the simulation of overflow and lost circulation processes, enabling the measurement of key parameters and providing a theoretical basis for controlling these phenomena and ensuring drilling safety.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If underbalanced drilling is used to alleviate lost circulation, then lost circulation is effectively alleviated or avoided, but overflow may occur in formations with narrow pressure windows
Solution Approach 1:
The patent dynamically adjusts wellbore pressure parameters to transition between underbalanced and overbalanced states. By changing the pressure regime based on real-time formation conditions, the system can alleviate lost circulation when needed while preventing overflow when formation pressure windows are narrow, thus resolving the contradiction between these two harmful effects.
Solution Approach 2:
The patent implements a feedback control system that monitors wellbore pressure, formation pressure, and drilling parameters in real-time. Based on this feedback, the system automatically adjusts drilling parameters to maintain pressure within safe limits, preventing both lost circulation and overflow by adapting to changing formation conditions.
2Reliability
If managed pressure drilling is used to keep wellbore pressure in near-balanced state, then overflow and serious lost circulation are avoided, but drilling efficiency decreases in fractured formations
Solution Approach 1:
The patent transitions from static pressure control to dynamic pressure management. The system continuously adjusts wellbore pressure based on real-time drilling conditions, fracture detection, and formation pressure data. This dynamic approach allows the system to optimize pressure for both safety and drilling efficiency, resolving the contradiction between controlled pressure and drilling productivity.
Solution Approach 2:
The patent changes drilling parameters such as mud weight, flow rate, and pressure control strategies based on detected fracture conditions and formation characteristics. By adapting these parameters dynamically, the system maintains pressure control while improving drilling efficiency in fractured formations.
3Productivity
If drilling continues in fractured formation with co-existence of overflow and lost circulation, then drilling operation is maintained, but safety risks increase
Solution Approach 1:
The patent employs real-time monitoring and feedback systems that detect changes in wellbore pressure, fluid flow patterns, and formation responses. When signs of co-existing overflow and lost circulation are detected, the system provides immediate feedback to adjust drilling parameters or suspend operations, thus maintaining safety while allowing controlled drilling continuity.
Solution Approach 2:
The patent implements preventive measures and safety margins in the drilling system design and operation. By preparing emergency response protocols, maintaining pressure control buffers, and using real-time monitoring to detect early signs of instability, the system cushions against safety risks while maintaining drilling operations.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The device effectively simulates various patterns of overflow and lost circulation, providing reliable data for controlling these conditions, enhancing drilling safety and facilitating effective plugging and well killing operations by allowing for the adjustment of fracture parameters and wellbore conditions.
Implementation Method 1
the gas injection system comprises an air compressor and a gas flowmeter; and an outlet end of the air compressor is connected to the upper overflow port and the lower overflow port through the gas flowmeter and a third pipeline
Implementation Method 2
the liquid injection system comprises a liquid storage tank, a water pump, a second liquid flowmeter, and a liquid regulating valve
Implementation Method 3
the simulated formation fracture unit comprises a support block, a sealing gasket, a first liquid flowmeter, a lost liquid collection tank, two clamp plates, a fracture model, and a bolt; the two clamp plates are connected through the bolt and the support block, and a gap is formed between the two clamp plates
Data Source
AI summary
An experimental device and method for co-existence of overflow and lost circulation in a fractured formation during drilling of a deviated well are provided. An inner cavity of an outer pipe is provided with an inner pipe to form a deviated casing. An upper side of the outer pipe is provided with a mixture outlet. A middle-lower side of the outer pipe is provided with a leakage port and two overflow ports. The gap width can be changed by adjusting a bolt and a support block to be compatible with different types of fracture models. A gas injection system includes an air compressor and a gas flowmeter. An upper port of a liquid injection system is connected to a joint arranged at upper ends of the inner pipe and outer pipe through a water pump, a liquid flowmeter and a liquid regulating valve.