Continuous Downhole Choke for Electric Flow Control and Erosion Resistance

The patent replaces the traditional hydraulic actuation system with an electro-mechanical actuator that uses electrical inputs to directly drive the piston. This substitution eliminates the need for complex hydraulic seals, accumulators, and control systems while maintaining sufficient force generation through the electro-mechanical converter, thereby reducing overall device complexity while preserving load capacity.

The patent eliminates hydraulic systems entirely in favor of direct electro-mechanical actuation. The electro-mechanical actuator converts electrical energy directly into mechanical motion to move the piston, removing the intermediary hydraulic fluid system and its associated complexity, while still providing the necessary force for flow control in high-pressure environments.

The patent transitions from a static discrete-position choke system to a dynamic continuous-position system. The piston can move freely along the choke sleeve to any position within the stroke range, enabling continuous adjustment of the flow area. This dynamic positioning capability provides smooth, responsive flow control without the step-like characteristics of discrete positions, while manufacturing precision is maintained through precise machining of the piston and sleeve interfaces.

The patent divides the continuous stroke into numerous potential positions through precise machining of the piston and sleeve, effectively creating a segmented control mechanism that appears continuous but can be positioned at multiple discrete locations if needed. This segmentation approach allows for both continuous flow control and precise positioning capability.

The patent employs tungsten carbide, a composite material with exceptional hardness and erosion resistance, for the piston and choke sleeve components. This material choice provides superior durability in high-flow, high-erosion environments compared to conventional metals or polymers, while remaining manufacturable through established ceramic/composite fabrication processes. The use of tungsten carbide directly addresses the erosion resistance requirement without significantly complicating the manufacturing process.

The patent changes the material parameter of the piston and sleeve from conventional materials to tungsten carbide, which has superior hardness and erosion resistance properties. This material parameter change enables the valve to withstand high-flow conditions and severe erosion while maintaining manufacturing feasibility through appropriate fabrication techniques for hard materials.

The patent uses tungsten carbide material for the piston and sleeve, which provides exceptional erosion and wear resistance. This allows the piston to move at higher speeds for faster response without suffering excessive erosion, as the hard material withstands the increased mechanical stress and fluid impact that would normally cause rapid degradation of softer materials.

The patent incorporates sealing features and proper clearance design that prevent direct metal-to-metal contact and reduce the impact of high-speed piston movement on the sealing surfaces. The sealing system is designed to accommodate the operational forces generated during high-speed movement, cushioning the effects of erosion and wear before they can damage the critical sealing interfaces.