| 摘要 |
<p>The high-speed seal is a two-part metal-to-metal type seal that, in its initial application, acts as a conventional resilient O-ring. As the seal begins to operate, a separate O-ring, retained within a seal gland channel formed in the body of a primary metal seal, provides an initial seal. As the seal continues to function over a length of time, the separate O-ring retained within the seal gland in the ring 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> |
