NCCCO Drill Rig key terms

The amount of load a drill rig imposes on the soil beneath each outrigger, track, or pad, usually expressed in pounds per square foot and compared against the soil's rated capacity.

A pad or plate placed under an outrigger to spread its load over a wider area, reducing ground bearing pressure and limiting settlement during drilling and lifting.

Timber, steel, or composite pads laid under tracks or outriggers to distribute weight, bridge soft spots, and keep the rig level on unstable or uneven ground.

A person who, by training and experience, can identify existing and predictable hazards and has authority to take prompt corrective action to eliminate them.

A person who, by possession of a recognized degree, certificate, or professional standing, or by extensive experience, has demonstrated ability to solve problems relating to a specific subject.

A documented walk-around and function check of the drill rig, rigging, and safety devices performed before each shift or after any event that could affect safe operation.

A manufacturer-supplied table or graph that gives the maximum permissible load for a given boom length, radius, and configuration, with deductions for attachments and rigging.

An instrument that measures boom angle and load to warn the operator when capacity is approached and to stop functions when the rated capacity is exceeded.

The rated capacity remaining after subtracting the weight of the hook block, slings, shackles, and other rigging from the gross capacity shown on the load chart.

The horizontal distance from the rotation center of the rig to the center line of the load, which directly determines the capacity available on the load chart.

The angle between the boom centerline and horizontal, used with boom length to find radius and capacity and to keep the load within the charted working range.

A sensing device that warns and stops the hoist when the hook block approaches the boom tip too closely, preventing two-blocking, wire rope damage, and load loss.

The angle between a sling leg and the horizontal, which controls the tension in each leg and the resulting load applied to the hook and rigging.

A U-shaped rigging connector closed with a pin or bolt, rated for a specific working load limit and used to join slings to hooks, eyes, or pad eyes.

The maximum load a rigging component, sling, or attachment is rated to carry in a specific configuration, as marked by the manufacturer and never exceeded.

A rope attached to a suspended load so a worker can control rotation and swing from outside the fall zone, keeping hands clear of the load and rigging.

The area swept by the rotating upper structure, counterweight, or suspended load, which must be barricaded or kept clear of personnel during operation.

A marked or barricaded area around the drill rig and rotating equipment where only authorized personnel may enter, protecting workers from swing, auger, and hoist hazards.

Any location where a body part can be caught between moving and stationary parts, such as auger flights, rod joints, or rotating shafts, requiring guarding or distance.

A procedure that isolates hazardous energy, applies a lock and tag, and verifies zero energy before maintenance or repair on the rig or its attachments.

A documented examination of hoist and boom lines for broken wires, corrosion, kinks, crushing, and diameter loss, with removal criteria set by the manufacturer or standard.

The assembled column of drill pipe, collars, and tools that transmits rotation and thrust from the rig to the bit at the bottom of the hole.

A sliding or hexagonal drive bar that transfers rotation from the rotary table to the drill string while allowing the string to move up and down.

The powered deck component that rotates the kelly or drill string and supports the weight of the string during drilling operations.

Rotating and pulling the drill string upward to enlarge or clean the hole while withdrawing, which requires controlled pull force and monitoring of torque and cuttings.

The distance the bit advances per unit of time, affected by thrust, rotation speed, torque, soil or rock type, and fluid or air circulation.

Liquid or air circulated down the hole to cool the bit, remove cuttings, and stabilize the borehole wall, with properties monitored to prevent loss or blowout.

The pump that circulates drilling fluid through the string and back up the annulus, with pressure and flow watched to keep the hole clean and stable.

The excavated soil, rock, or slurry solids removed from the hole and stockpiled, which must be placed to avoid surcharging the hole and blocking access.

The planned arrangement of the drill rig, access roads, spoil areas, utilities, and exclusion zones that supports safe operation and efficient production.

The process of identifying and marking buried lines such as gas, electric, and water before drilling, using records, locating equipment, and visual verification.

A documented plan prepared or approved by a qualified person for critical or non-standard lifts, specifying equipment, rigging, capacity checks, and sequence.

Adjusting outriggers or jacks so the rig deck and mast are within the manufacturer's tolerance, which is required before raising the mast or drilling.

The sequence of unfolding and pinning the mast to its operating position, performed only after leveling, pinning checks, and clearance verification.

A clearly marked control that immediately halts rig functions, used when a person, utility, or load is at risk, followed by shutdown and reporting procedures.

A portable extinguisher of the correct class and size, inspected and accessible on the rig, for use on fuel, hydraulic, or electrical fires during operations.

Standardized visual commands given by a designated signal person to the operator when voice or radio communication is unreliable, understood by all crew members.

The identification of ground conditions by type and behavior, used to select drilling tools, set casing, and judge whether the working surface can carry the rig.