| 摘要 |
<p>HIGH SPEED SEAL The high speed seal is an integral metal-to-metal type seal that, in its initial application, acts as a regular resilient O-ring. As the seal begins to operate, a protruding circular resilient lip adjacent the metal sealing ring provides an initial seal and, as the seal continues to function over a length of time, the resilient portion wears away and metal-to-metal . contact begins to be made. Thus the seal gradually converts from-a standard O-ring type of seal to a lapped-in metal-to-metal seal during operation of the bit.</p> |
