Tubing Plugging Valve

Description

The tubing plugging valve is an internal blowout control tool designed for special needs during well testing and workover. The biggest safety risk is replacing the wellhead without control; this retrievable valve plugs the tubing to eliminate the risk of tubing blowout while the tree and BOP are replaced and installed.

The tool is delivered to the planned setting position by a special running and retrieving device. Rotating the device to the left expands the rubber element and sets the two-way anchors, plugging the tubing. Rotating it to the right unsets the valve so it can be pulled out, restoring full bore. While the tubing is plugged, pressure can be applied in the tubing to knock out the plug for circulation and well killing.

Structure & operation

The tool mainly consists of a top adapter, drag block, slips, rubber element, plugging section and special delivery device.

Run the tool to the setting position with the delivery device and rotate left to open the slips and compress the element, setting the tool in the tubing and isolating the tubing above from below. Pick up and rotate left to remove the delivery device.

Before unsetting, apply tubing pressure to shoot down the plug at the bottom of the tool. Keep the tubing open and observe tubing pressure; if there is pressure, perform a squeeze job and unset only after the pressure has been released. If there is no pressure, observe for 5–10 minutes, then run the delivery device to engage the top adapter, rotate right to retract the element and slips, and pull the tool out.