The TCO Autofill Sub is a downhole completion tool designed to allow the tubing to self-fill with well fluid during run-in-hole (RIH), thereby simplifying operations and eliminating the need for external fluid-filling systems. Installed above a glass plug such as the TDP-PO, the Autofill Sub provides a temporary open flow path between the annulus and the inside of the tubing string. This allows the completion string to fill naturally with well fluid as it is lowered into position.

When the completion reaches depth, hydrostatic and surface pressure activation closes the flow path – creating creating a reliable VO barrier that maintains well integrity and allows activation of the glass plug below under pressure.

The Autofill Sub is designed to operate in high-temperature and pressure environments (up to 5,000 psi) and can be built from material configurations suited for the well conditions to provide durability, corrosion resistance, and performance consistency. Once the sleeve has closed, it provides a permanent seal that isolates the tubing from the annulus pressure.

Designed to integrate directly into the completion string, the Autofill Sub enhances TCO’s portfolio of completion technologies, providing a fully compatible solution that complements our laminated glass plugs. This allows operators to execute safer, faster completions while reducing dependence on third-party autofill systems.