To string a wire rope drilling line through the sheaves of the traveling and crown blocks to the hoisting drum.

A valve that will open automatically when pressure gets too high.

See red-lime mud.

To pass (as a rope) through a hole or opening in a block or similar device.

1.

The ratio of the weight of a given volume of a substance at a given temperature to the weight of an equal volume of a standard substance at the same temperature.

For example, if 1 cubic inch of water at 39 degrees f weighs 1 unit and 1 cubic inch of another solid or liquid at 39 degrees f weight 0.95 unit, then the relative density of the substance is 0.95.

In determining the relative density of gases, the comparison is made with the standard of air or hydrogen.

2.

The ratio of the mass of a given volume of a substance to the mass of a like volume of a standard substance, such as water or air.

3.

The ratio of the density (mass of a unit volume) of a substance to the density of a given reference material.

Specific gravity usually means relative density with respect to water.

The term “relative density” is often preferred in modern scientific usage.

See ram blowout preventer.

Rate (commonly given in rpm) at which an action resulting from applied forces causes or tends to cause two adjacent parts of a body to slide relative to each other in a direction parallel to their plane of contact.

1.

A hole in the rig floor, 30 to 35 feet (9 to 11 meters) deep, which is lined with casing that projects above the floor and into which the kelly and swivel are placed when hoisting operations are in progress.

2.

A hole of a diameter smaller than the main hole and drilled in the bottom of the main hole.

v: to reduce the size of the wellbore and drill ahead.

Two or more atoms behaving as a single chemical unit, i.e., as an atom, e.g., sulfate, phosphate, nitrate.

In sucker rod pumping, the difference between the polished rod peak load on the upstroke and the minimum load on the downstroke.

To enlarge the wellbore by drilling it again with a special bit.

Often a rathole is reamed or opened to the same size as the main wellbore.

See rathole.

Abbreviation: radioactive densiometer; fluid-measuring device to measure density.

After the initial completion of a well, the action and techniques of reentering the well and redoing or repairing the original completion to restore the well’s productivity.

A pump consisting of a piston that moves back and forth or up and down in a cylinder.

The cylinder is equipped with inlet (suction) and outlet (discharge) valves.

On the intake stroke, the suction valves are opened, and fluid is drawn into the cylinder.

On the discharge stroke, the suction valves close, the discharge valves open, and fluid is forced out of the cylinder.

A tool used in drilling to smooth the wall of a well, enlarge the hole to the specified size, help stabilize the bit, straighten the wellbore if kinks or doglegs are encountered, and rill directionally.

See ream.