hang rods v: to suspend sucker rods in a derrick or mast on rod hangers
rather than to place them horizontally on a rack.
hard hat n: a hard helmet worn by oilfield workers
to minimize the danger of being injured by falling objects.
headache n: (slang) the position in which the mast
on a mobile rig is resting horizontally over the driver’s cab.
hex kelly n: see kelly.
hoist n: 1. an arrangement of pulleys and wire rope used for lifting
heavy objects; a winch or similar device. 2. the drawworks. v: to raise or
hoisting components n pl: drawworks, drilling line, and traveling and
crown blocks. Auxiliary hoisting components include catheads, catshaft, and
hoisting drum n: the large, flanged spool in the drawworks on which the
hoisting cable is wound. See drawworks.
line n: a wire rope used in hoisting operations.
hook n: a large, hook-shaped device from which the elevator bails or the swivel is
suspended. It turns on bearings in its supporting housing.
hoisting system n: the system on the rig that
performs all the lifting on the rig, primarily the lifting and lowering of
drill pipe out of and into the hole. It is composed of drilling line,
traveling block, crown block, and drawworks. See also hoisting components.
hook load n: the weight of the drill stem and
associated components that are suspended from the hook.
hopper n: a large funnel- or cone-shaped device into which dry
components (such as powdered clay or cement) can be poured to later mix with
water or other liquids. The dry component is educted through a nozzle at the
bottom of the hopper.
horsehead n: the generally horsehead-shaped steel
piece at the front of the beam of a pumping unit to which the bridle is
attached in sucker rod pumping.
horsepower n: a unit of measure of work done by a
horizontal drilling n: deviation of the borehole
from vertical so that the borehole penetrates a productive formation in a
manner parallel to the formation.
hydraulic adj: 1. of or relating to water or other
liquid in motion. 2. operated, moved, or effected by water or liquid.
hydraulic fluid n: a liquid of low viscosity (such
as light oil) that is used in systems actuated by liquid (such as the brake
system in a car).
hydraulic force n: force resulting from pressure on
water or other hydraulic fluid.
hydraulic fracturing n: an operation in which a specially blended
liquid is pumped down a well and into a formation under pressure high enough
to cause the formation to crack open, forming passages through which oil can
flow into the wellbore.
hydraulic jar n: a type of mechanical jar in which a
fluid moving through a small opening slows the piston stroke while the crew
stretches the work string. After the hydraulic delay, a release mechanism in
the jar trips to allow a mandrel to spring up and deliver a sharp blow.
Compare mechanical jar.
hydraulic pumping n: a method of pumping oil from
wells by using a downhole pump without sucker rods. Subsurface hydraulic pumps
consist of two reciprocating pumps coupled and placed in the well. One pump
functions as an engine and drives the other pump (the production pump). The
downhole engine is usually operated by clean crude oil under under pressure
(power oil) that is drawn from a power-oil settling tank by a triplex plunger
pump on the surface. If a single string of tubing is used, power oil is pumped
down the tubing string to the pump, which is seated in the string, and a
mixture of power oil and produced fluid is returned through the casing-tubing
annulus. If two parallel strings are used, one supplies power oil to the pump
while the other returns the exhaust and produced oil to the surface. A
hydraulic pump may be used to pump several wells from a central source.
hydrocarbons n pl: organic compounds of hydrogen and
carbon whose densities, boiling points, and freezing points increase as their
molecular weights increase. Although composed of only two elements,
hydrocarbons exist in a variety of compounds, because of the strong affinity
of the carbon atom for other atoms and for itself. The smallest molecules of
hydrocarbons are gaseous; the largest are solids. Petroleum is a mixture of
many different hydrocarbons.
hydrogen sulfide cracking n: a type of corrosion
that occurs when metals are exposed to hydrogen sulfide gas; it is
characterized by minute cracks that form just under the metal’s surface.
hydrostatic pressure n: the force exerted by a body
of fluid at rest. It increases directly with the density and the depth of the
fluid and is expressed in many different units, including pounds per square
inch or kilopascals.