Clamp holding fixtures on ends of hoisting cables.
Control the viscosity and weight of the drilling fluid.
Guide lengths of pipe into and out of elevators.
Inspect derricks for flaws, and clean and oil derricks in order to maintain proper working conditions.
Inspect derricks, or order their inspection, prior to being raised or lowered.
Listen to mud pumps and check regularly for vibration and other problems, in order to ensure that rig pumps and drilling mud systems are working properly.
Position and align derrick elements, using harnesses and platform climbing devices.
Set and bolt crown blocks to posts at tops of derricks.
Start pumps that circulate mud through drill pipes and boreholes to cool drill bits and flush out drill-cuttings.
Steady pipes during connection to or disconnection from drill or casing strings.
String cables through pulleys and blocks.
Prepare mud reports, and instruct crews about the handling of any chemical additives.
Repair pumps, mud tanks, and related equipment.
Supervise crew members, and provide assistance in training them.
Weigh clay, and mix with water and chemicals in order to make drilling mud, using portable mixers.
Mechanical -- Knowledge of machines and tools, including their designs, uses, repair, and maintenance.
Operation and Control -- Controlling operations of equipment or systems.
Repairing -- Repairing machines or systems using the needed tools.
Equipment Maintenance -- Performing routine maintenance on equipment and determining when and what kind of maintenance is needed.
Operation Monitoring -- Watching gauges, dials, or other indicators to make sure a machine is working properly.
Equipment Selection -- Determining the kind of tools and equipment needed to do a job.
Troubleshooting -- Determining causes of operating errors and deciding what to do about it.
Manual Dexterity -- The ability to quickly move your hand, your hand together with your arm, or your two hands to grasp, manipulate, or assemble objects.
Controlling Machines and Processes -- Using either control mechanisms or direct physical activity to operate machines or processes (not including computers or vehicles).
Handling and Moving Objects -- Using hands and arms in handling, installing, positioning, and moving materials, and manipulating things.
Performing General Physical Activities -- Performing physical activities that require considerable use of your arms and legs and moving your whole body, such as climbing, lifting, balancing, walking, stooping, and handling of materials.
Repairing and Maintaining Mechanical Equipment -- Servicing, repairing, adjusting, and testing machines, devices, moving parts, and equipment that operate primarily on the basis of mechanical (not electronic) principles.
Monitor Processes, Materials, or Surroundings -- Monitoring and reviewing information from materials, events, or the environment, to detect or assess problems.
Inspecting Equipment, Structures, or Material -- Inspecting equipment, structures, or materials to identify the cause of errors or other problems or defects.
Getting Information -- Observing, receiving, and otherwise obtaining information from all relevant sources.