| 摘要 |
<p>RAM BLOCKS FOR HYDROGEN SULFIDE SERVICE Ram blocks for engaging and supporting drill pipe passing through blowout preventers encountering hydrogen sulfide are disclosed. The ram blocks are formed of an alloy having an upper hardness level of about Rc22 and the drill string or pipe engaging surfaces are hardfaced with a layer of nickel-based alloys, cobalt-based alloys, and tungsten-based alloys having a hardness sufficient to engage and support the drill pipe. The layer is thin enough to avoid peeling off in use and warping the ram blocks when being welded to them. A number of embodiments and examples of the invention is disclosed.</p> |
