A rotary drilling rig works by rotating a drill string, which applies downward pressure to a drill bit that grinds the earth. Drilling fluid or air is pumped down the drill string to cool the bit, carry cuttings to the surface, and stabilize the borehole.
[pdf] The hydraulic system is the muscle of the crawler mounted drill rig, and its control is a vital part of the overall control system. Hydraulic valves are used to direct the flow of hydraulic fluid to different actuators, such as cylinders and motors.
[pdf] A flow line, used on a drilling rig, is a large diameter pipe (typically a section of casing) that is connected to the bell nipple (under the drill floor) and extends to the possum belly (on the mud tanks) and acts as a return line (for the drilling fluid as it comes out of the hole), to the mud. .
The is used to slow the flow of returning before it hits the . This enables the shale shaker to clean the. .
A stinger line is similar to a flow line, but unlike a flow line is not used to maintain circulation. The stinger line is attached to the .
Another common add on is the sample box. This is a heavy duty rubber hose that is inserted at the end of the flow line and at the other end emplaced into the sample box itself. The.
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