| 摘要 |
<p>This invention relates to the replacement of seals in ram type blow out preventers and is especially useful for replacing such seals where the well head is at a considerable distance from the drill head, for example on the sea bed. The method comprises removing a seal from a first blow out preventer ram in situ at the lower end of the well riser, and inserting a replacement shoe of smaller internal diameter itself fitted with a seal within the seal recess of the first ram. There is disclosed a shoe for a ram type blow out preventer comprising a part annular member having a part cylindrical outer surface provided with a ridge for receipt in a recess in a blow out preventer ram, means for indexing and securing the part annular member relative to the blow out preventer ram, and a seal receiving recess in the radially inner surface of the part annular member.</p> |
