Internal Sleeve Drain

Republic Oil Tools Tubing Internal Sleeve Drain (ISD) is a pressure-actuated sleeve drain designed to allow fluid drainage from the tubing, preventing the need for retrieval while it’s wet. 

Typical applications include Permanent Magnet Motor (PMM) Electric Submersible Pumps (ESP).

In the PMM-ESP configuration, the ISD serves as a path of least resistance for fluid flow, preventing the PMM from spinning. This offers a reliable alternative to perforating the tubing string, which can otherwise damage the motor’s lead extension or power cable. 

The Internal Sleeve Drain differs from the External Sleeve Drain in that it is pressure-balanced, eliminating premature pin shearing. This provides operators with peace of mind, ensuring no premature workover. The positive barrier is only established when the PMM Dart is dropped and lands inside the drain, preventing fluid movement up or down the tubing string. Positive pressure above the dart will shear the pins, opening the drain. Alternatively, the ISD can be actuated with a ball if a dart is undesirable. Additionally, for pressure testing purposes, a dissolvable ball can be landed on the drain as long as the test pressure remains below the shear pin value.