Adjustable Cone Expander for Tubular Elements

The expander employs a dynamic adjustable cone that can change its radial position between expanded and collapsed modes. The cone is biased outward by a spring mechanism but can be pushed inward by thrust forces generated during expansion, allowing it to adapt dynamically to wellbore conditions. This dynamic adjustment enables the expander to maintain reliability by expanding against irregularities while preserving mobility by collapsing when encountering obstructions.

The expander changes the geometric parameter of the cone's radial position based on operating conditions. When the tubular element offers sufficient resistance, the cone maintains its expanded position. When obstructions are encountered and resistance increases abnormally, the cone transitions to a collapsed position with reduced diameter, allowing the expander to pass through. This parameter change resolves the contradiction between maintaining expansion reliability and ensuring operational mobility.

The expander uses a self-service mechanism where the thrust force generated during the expansion process itself is utilized to adjust the cone's position. The spring mechanism provides a simple biasing force that requires no complex control system. The cone automatically transitions between expanded and collapsed modes based on the balance between spring force and thrust force, eliminating the need for complex preload control mechanisms while maintaining sufficient expansion force.

The invention replaces a complex controlled preload system with a simple spring-based mechanical biasing system. Instead of using actuators, sensors, and control algorithms to manage the cone's position, a spring provides continuous outward biasing force that is automatically balanced by the inward thrust force during expansion. This mechanical substitution dramatically reduces device complexity while maintaining the necessary expansion force capability.

The adjustable cone transitions from a static large-diameter design to a dynamic structure that can change its effective diameter. During normal expansion against regular wellbore walls, the cone maintains its expanded position for precise expansion. When encountering obstructions or irregularities, the cone dynamically collapses to a smaller diameter, allowing the expander to navigate through the wellbore. This dynamic behavior provides both expansion precision and adaptability to varying wellbore conditions.

The spring mechanism pre-biases the cone toward the expanded position before expansion begins, ensuring that the expander is ready to exert full expansion force immediately upon contact with the tubular element. This preliminary action eliminates the need for gradual expansion sequences while maintaining the ability to collapse when obstructions are encountered, thus preserving both expansion precision and adaptability.