A wear bushing, or sleeve, is installed in the casing head housing, or indeed in any compact or casing head spool, to protect the hanger landing preparations from damage while the drill string, tools, or other tubulars are run through, or rotated in, the wellhead. .
In some systems, the sleeve is held in place by a set of tie-down bolts contained either in the top flange of the housing or in a separate hold-down flange installed between the housing.
[pdf] The IADC Drilling Manual has recently been updated and is now available in its 13th edition in the IADC Bookstore. This book is the definitive manual for drilling operations, training, maintenance and troubleshooting.
[pdf] Each screw machine must be equipped with a gas storage tank and, if needed, auxiliary equipment such as a cold dryer and a filter. The installation requirements are as follows: A) The installation sequence of supporting equipment is: “air compressor → gas tank → gas-water separator → cold dryer.”
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