摘要 |
A ball within a ball valve comprises a ball, an interior fluid passage extending through the ball, a first flow passage disposed in the ball that allows fluid communication between an exterior fluid and the interior fluid passage, a second flow passage disposed in the ball that extends through a wall of the ball to the interior fluid passage, where the first flow passage and the second flow passage are on opposite hemispheres of the ball, and a flow through device. The flow through device comprises a plug disposed in the second flow passage and configured to sealingly engage the ball, and a shear device configured to engage the plug and retain the plug in the second flow passage. |