Changes

The ''[[derrick]]'' supports the crown block and provides a place to stack pipe that is pulled out of the hole. The depth rating of the derrick is related to the size of the rig. The height of the derrick is commonly referred to in multiples of pipe joints (a joint of pipe is approximately 30 ft long). Rigs that can stack double joints of drill pipe are called ''double derricks'', and those that stack three joints are called ''treble derricks''. Part way up the derrick are the ''monkey board'' (3) and ''[[pipe finger]]s''. The derrickman handles the top end of each stand of pipe from the monkey board during trips. The pipe is racked in the finger boards and tied off to keep it from falling. The derrick ''substructure'' (23), the platform under the derrick, is rated by set back capacity; that is, the weight of the drill string stacked in the derrick plus the weight of [[casing]] that can be lifted. The height of the substructure is dictated by the height of the [[blowout preventer]]s (38). The top of the substructure is called the ''[[derrick floor]]''. This is the primary working area of the rig.

The ''[[derrick]]'' supports the crown block and provides a place to stack pipe that is pulled out of the hole. The depth rating of the derrick is related to the size of the rig. The height of the derrick is commonly referred to in multiples of pipe joints (a joint of pipe is approximately 30 ft long). Rigs that can stack double joints of drill pipe are called ''double derricks'', and those that stack three joints are called ''treble derricks''. Part way up the derrick are the ''monkey board'' (3) and ''[[pipe finger]]s''. The derrickman handles the top end of each stand of pipe from the monkey board during trips. The pipe is racked in the finger boards and tied off to keep it from falling. The derrick ''substructure'' (23), the platform under the derrick, is rated by set back capacity; that is, the weight of the drill string stacked in the derrick plus the weight of [[casing]] that can be lifted. The height of the substructure is dictated by the height of the [[blowout preventer]]s (38). The top of the substructure is called the ''[[derrick floor]]''. This is the primary working area of the rig.

The ''[[catwalk]]'' is the deck located to the side of the derrick floor and between the pipe racks (22). Joints of drill pipe and casing are rolled from the pipe racks where they are stored on the catwalk and hoisted up through the [[slide]] and [[V-door]]. The catwalk is also the primary location to process [[Core handling|core]] and assemble [[Basic tool table|wireline logging tools]].

The ''[[catwalk]]'' is the deck located to the side of the derrick floor and between the pipe racks (22). Joints of drill pipe and casing are rolled from the pipe racks where they are stored on the catwalk and hoisted up through the [[slide]] (21) and [[V-door]]. The catwalk is also the primary location to process [[Core handling|core]] and assemble [[Basic tool table|wireline logging tools]].

[[file:land-rigs_fig2.png|thumb|{{figure number|2}}Circulating system of a rig. (From <ref name=pt03r50>Whittaker, A., ed., 1985, Field geologists training guide: Boston, MA, IHRDC, 291 p.</ref>.)]]

[[file:land-rigs_fig2.png|thumb|{{figure number|2}}Circulating system of a rig. (From <ref name=pt03r50>Whittaker, A., ed., 1985, Field geologists training guide: Boston, MA, IHRDC, 291 p.</ref>.)]]