Millable Bit Connector for Wellbore Departure Device Placement
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current wellbore departure methods face challenges in efficiently and predictably placing and anchoring departure devices in openhole wellbores due to variations in formation geometry, strength, and fluid pressures, which complicates the formation of lateral boreholes.
Innovation Solution
A connector system that couples a bit to a departure device, where the connector is designed to be more millable than the departure device, allowing it to be milled away by the bit, facilitating the placement and anchoring of the departure device within the wellbore, and an expandable anchor secures the system in place.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If a connector is made of strong material to withstand push and torque loading, then the connector can transmit forces effectively, but the connector becomes difficult to mill away
Solution Approach 1:
The connector is designed with non-uniform material properties: the body portion has higher yield strength (30-70 ksi) to withstand loading, while the transition zone has lower yield strength (10-30 ksi) to facilitate milling. This local differentiation allows the connector to simultaneously achieve strength where needed and ease of removal where required.
Solution Approach 2:
The connector is segmented into distinct zones with different material properties: a strong body portion for force transmission, a weaker transition zone for controlled failure/milling, and connection areas for interfacing with the departure device and drill string. This segmentation enables each zone to perform its specific function optimally.
2Ease of manufacture
If the connector is designed to be easily milled away, then lateral borehole formation is facilitated, but the connector may fail to transmit sufficient push and torque forces
Solution Approach 1:
The connector is designed with non-uniform material properties: the body portion has higher yield strength (30-70 ksi) to withstand loading, while the transition zone has lower yield strength (10-30 ksi) to facilitate milling. This local differentiation allows the connector to simultaneously achieve strength where needed and ease of removal where required.
3Strength
If the connector material has high yield strength, then the connector can withstand downhole forces, but the connector becomes more difficult to remove by milling
Solution Approach 1:
The connector is designed with non-uniform material properties: the body portion has higher yield strength (30-70 ksi) to withstand loading, while the transition zone has lower yield strength (10-30 ksi) to facilitate milling. This local differentiation allows the connector to simultaneously achieve strength where needed and ease of removal where required.
Solution Approach 2:
The connector is segmented into distinct zones with different material properties: a strong body portion for force transmission, a weaker transition zone for controlled failure/milling, and connection areas for interfacing with the departure device and drill string. This segmentation enables each zone to perform its specific function optimally.
Data Source
AI summary
A departure device couples to a bit using a connector that facilitates release of the bit from the departure device. The connector may be more millable than the departure device and can transmit axial and torque loads between the bit and the departure device. The connector may include a material having lesser strength or hardness than the departure device, and may be millable by the bit. Another example connector may have connection points with the bit, and a movable member of the departure device may a force to the connector and contribute to releasing the connection between the bit and the departure device. A tensile connector between the bit and the movable member may apply a tension force to the movable member, urging the movable member toward an extended position in which the movable member is aligned coherently with a sloped face of the departure device.