critical taper
An equilibrial angle made by the far end of a body of wedge-shaped material being pushed by the near end.
Mechanical engineering
250 entries in this trade.
crosshead
A metal beam that connects a piston to a connecting rod in an engine.
damping
The reduction in the magnitude of oscillations by the dissipation of energy.
dead air
Air that is subject to little or no ventilation, thus, little to no air exchange.
deformation
The act of deforming, or state of being deformed.
detonation
Engine knocking, a type of improper combustion in gasoline piston engines.
diaphragm
A flexible membrane separating two chambers and fixed around its periphery that distends into one or other chamber as the difference in the pressure in the chambers varies.
diesel engine
An internal combustion engine of piston engine type that operates using the Diesel cycle, with diesel fuel being sprayed into the hot, high-pressure air in the combustion chamber at the end of the compression stroke.
diesel-hydraulic
adjectiveMechanical engineering
Powered by a diesel engine via a hydraulic transmission.
differential steering
Steering by means of driving the wheels or treads on one side of a vehicle faster than those on the other side, or driving the wheels or treads on one side in the forward and on the other side in the reverse direction.
dipstick
To measure the level of a fluid using a dipstick.
documentation
Documents that explain the operation of a particular machine or software program.
double-acting
adjectiveMechanical engineering
Applying power in two directions.
drillable
adjectiveMechanical engineering
Having an arm or manipulator that can position the tool or attachment at the end in different orientations.
drivetrain
The mechanical parts of the powertrain, the gears and shafts, that connect the engine to the wheels in a vehicle.
drop hammer
A heavy weight that is raised and then allowed to drop, as used for piledriving and drop-forging.
dropping point
The temperature at which a grease passes from a semi-solid to a liquid state under specific test conditions.
dry heater
A torpedo engine powered by the burning of fuel with compressed air or oxygen, which does not inject water into the combustion chamber for engine cooling and extra power.
ductile fracture
type of fracture with plastic deformation and ductile rupture
ECTS
Initialism of engine coolant temperature sensor.
ejector
A jet jump for lifting water or withdrawing air from a space.
elliptic spring
A curved leaf spring of different styles.
enrichener
The choke of a motor vehicle.
epsilon-machine
A deterministic automaton consisting of a system of causal states and the transitions between them, functioning as the smallest possible maximally predictive model of a stochastic process
equalising beam
A steel beam linking the suspension of two or more adjacent axles of a vehicle with at least two axles, especially on railway locomotive bogies.
escapement
The linkage in a (watch) that gives impulses to the timekeeping element and periodically releases the gear train to move forward, advancing the clock's hands.
face
The width of a pulley, or the length of a cog from end to end.
FEM
Initialism of finite element method.
finger-piece
A mechanical or structural component designed to be touched, held, or guided by the fingers.
fitting
A (generally small) component or part of a device or machine, especially one that is standardized and replaceable; specifically, a standardized part of a piping system used to connect sections of pipe together, such as a coupling.
flange
To make a flange on; to furnish with a flange; to bend (esp. sheet metal) in the form of a flange.
fluid flywheel
A type of coupling for transmitting power from the engine of a vehicle to the transmission, using a torque converter.
fluid mechanics
The branch of mechanics dealing with gases and liquids, either at rest or in motion.
flyweight
A weight that moves outward depending on centrifugal force.
flywheel
A rotating mass used to maintain the speed of a machine within certain limits while the machine receives or releases energy at a varying rate, or as a form of energy storage.
force pair
Two forces acting at the same point with equal magnitude but opposite direction, resulting from Newton's third law ("every action has an equal and opposite reaction").
forced induction
The process of blowing compressed air into the cylinders of an internal combustion piston engine to increase the compression ratio and power of the engine, typically by using a turbocharger or supercharger.
form factor
A factor describing the stress distribution of a body.
four-way cock
A cock connected with four pipes or ports, and having two or more passages in the plug, by which the adjacent pipes or ports may be made to communicate; formerly used as a valve in the steam engine, and for various other purposes.
fox
A wedge driven into the split end of a bolt to tighten it.
free surface effect
The tendency of liquids and liquid-like aggregates to move in response to changes in the attitude of a craft's cargo holds, decks, or liquid tanks in reaction to operator-induced motions (or sea states caused by waves and wind acting upon the craft).
free-fall time
The characteristic amount of time required for a body to collapse under its own gravitational attraction, if no other forces exist to oppose the collapse.
freewheel
Of a gear, to continue spinning after disengagement.
Galilean invariance
The principle that the laws of motion are the same in all inertial frames of reference.
gasket
Any mechanical seal that serves to fill the space between two objects, generally to prevent leakage between the two objects while under compression.
gear train
A system of interconnected gears.
gear wheel
A wheel with a toothed rim, intended to engage with others, or similar equipment, to form a gear.
Geneva mechanism
A mechanism that translates a continuous rotation into an intermittent rotary motion, using an intermittent gear where the drive wheel has a pin that reaches into a slot of the driven wheel and thereby advances it by one step, and having a raised circular blocking disc that locks the driven wheel in position between steps.
Geneva wheel
A mechanism that translates a continuous rotation into an intermittent rotary motion.
gland
A compressable cylindrical case and its contents around a shaft where it passes through a barrier, intended to prevent the passage of a fluid past the barrier, used for example around a ship’s propeller shaft or around a tap, valve or faucet.
gusset
A kind of bracket, or angular part, fastened in the angles of a structure to give strength or stiffness; especially, the part joining the barrel and the fire box of a locomotive boiler.
handbrake
The mechanism, particularly the locking hand-operated lever or foot-operated toggle lever in a motorcar or the hand-operated crank on a railcar, which is used to set and release such a brake.
handwheel
Any wheel worked by hand, whether used to allow leverage, as of a valve or a handbrake, or to allow fine adjustment, as of a set screw.
head gasket
The gasket which seals a cylinder head to an engine block in several types of engine, including steam engines and internal combustion engines.
high-time
adjectiveMechanical engineering
Having been in use for a (relatively) long time or a large number of operating cycles; nearing retirement or replacement age.
hunting cog
A tooth in the larger of a pair gear wheels, which makes its number of teeth prime to the number in the smaller wheel, thus preventing the frequent meeting of the same pairs of teeth and reducing wear.
hydrostatic lock
A condition that arises when a device which compresses gases seizes up because of the infiltration of liquid, which prevents further compression.
IAD
intelligent assist device
idle
The lowest selectable thrust or power setting of an engine.
ignition
A system for activating combustion in a combustion engine.