Rig derrick equipment and operate pumps to circulate mud through drill hole.
<ul><li>Inspect derricks, or order their inspection, prior to being raised or lowered.</li><li>Inspect derricks for flaws, and clean and oil derricks to maintain proper working conditions.</li><li>Control the viscosity and weight of the drilling fluid.</li><li>Repair pumps, mud tanks, and related equipment.</li><li>Set and bolt crown blocks to posts at tops of derricks.</li><li>Listen to mud pumps and check regularly for vibration and other problems to ensure that rig pumps and drilling mud systems are working properly.</li><li>Start pumps that circulate mud through drill pipes and boreholes to cool drill bits and flush out drill cuttings.</li><li>Position and align derrick elements, using harnesses and platform climbing devices.</li><li>Supervise crew members, and provide assistance in training them.</li><li>Guide lengths of pipe into and out of elevators.</li><li>Prepare mud reports, and instruct crews about the handling of any chemical additives.</li><li>Clamp holding fixtures on ends of hoisting cables.</li><li>Weigh clay, and mix with water and chemicals to make drilling mud, using portable mixers.</li><li>String cables through pulleys and blocks.</li><li>Steady pipes during connection to or disconnection from drill or casing strings.</li></ul>