| 摘要 |
<p>A hydraulically operated decoking tool capable of performing both boring and cutting operations with a simplified changeover between the operations that does not require removal of the tool from a coke bed is disclosed. The tool includes a body fabricated of durable material capable of withstanding the harsh environment in which it is used. Boring nozzles for boring a pilot hole in a coke bed and cutting nozzles for cutting up the coke for removal are provided on the tool. A coke bed is bored and cut by high pressure working fluid directed through the nozzles in a predetermined sequence. In the normal sequence, the boring operation is performed first followed by the cutting operation. The sequence of operations is controlled by a working fluid actuated shuttle sleeve or valve reciprocally mounted in the tool body. The sleeve is reciprocated by working fluid pressure moving from a first position corresponding to the boring operation to a second position corresponding to the cutting operation. In the first position, the sleeve blocks flow of working fluid to the cutting nozzles and opens flow of working fluid to the boring nozzles. Changeover between boring and cutting operations occurs automatically using working fluid pressure without the need to remove the tool from the coke bed and may be accomplished by an operator at a remote location through the use of a pilot valve.</p> |
