index

en-verb

index (third-person singular simple present indexes, present participle indexing, simple past and past participle indexed)

indexes (present singular third-person)
indexing (participle present)
indexed (participle past)
indexed (past)

From Latin index (“a discoverer, informer, spy; of things, an indicator, the forefinger, a title, superscription”), from indicō (“point out, show”); see indicate.

der

mechanical engineering
mechanical engineering

(mechanical engineering, transitive) To use a mechanism to move an object to a precise location.


bucket

→ Farefare: bɔgtɛ

→ Japanese: バケツ (baketsu)

→ Maori: pākete

From Middle English buket, boket, partly from Old English bucc ("bucket, pitcher"; mod. dialectal buck), equivalent to bouk + -et; and partly from Anglo-Norman buket, buquet (“tub; pail”) (compare Norman boutchet, Norman bouquet), diminutive of Old French buc (“abdomen; object with a cavity”), from Vulgar Latin *būcus (compare Occitan and Catalan buc, Italian buco, buca (“hole, gap”)), from Frankish *būk (“belly, stomach”). Both the Old English and Frankish terms derive from Proto-Germanic *būkaz (“belly, stomach”). More at bouk.

gloss

"bucket, pitcher"; mod. dialectal <i class="Latn mention" lang="en">buck</i>

der

(aviation, mechanical engineering, uncommon) A turbine blade driven by hot gas or steam.


SI

en-noun

SI (countable and uncountable, plural SIs)

(mechanical engineering) Initialism of spark ignition.


spin

spin (countable and uncountable, plural spins)

From Middle English spinnen, from Old English spinnan, from Proto-Germanic *spinnaną, from Proto-Indo-European *(s)penh₁-. Compare Low German spinnen, Dutch spinnen, German spinnen, Danish spinde, Swedish spinna.

(mechanical engineering) An abnormal condition in journal bearings where the bearing seizes to the rotating shaft and rotates inside the journal, destroying both the shaft and the journal.


shock

shock (countable and uncountable, plural shocks)

shocks (plural)
choque (alternative obsolete)

→ Bulgarian: шок (šok)

→ Chinese: 休克 (xiūkè)

→ Czech: šok

→ Italian: shock

→ Japanese: ショック (shokku)

→ Korean: 쇼크 (syokeu)

→ Macedonian: шок (šok)

→ Polish: szok

→ Russian: шок (šok)

→ Serbo-Croatian:

Cyrillic: шо̏к

Latin: šȍk

→ Slovak: šok

→ Spanish: shock

From Middle Dutch schokken (“to push, jolt, shake, jerk”) or Middle French choquer (“to collide with, clash”), from Old Dutch *skokkan (“to shake up and down, shog”), from Proto-Germanic *skukkaną (“to move, shake, tremble”). Of uncertain origin. Perhaps related to Proto-Germanic *skakaną (“to shake, stir”), from Proto-Indo-European *(s)kek-, *(s)keg- (“to shake, stir”); see shake.
Cognate with Middle Low German schocken (“collide with, deliver a blow to, move back and forth”), Old High German scoc (“a jolt, swing”), Middle High German schocken (“to swing”) (German schaukeln), Old Norse skykkr (“vibration, surging motion”), Icelandic skykkjun (“tremulously”), Middle English schiggen (“to shake”). Doublet of shog.

cog

shark (non-rhotic, father-bother merger)

If your truck's been riding rough, it might need new shocks.

We're bonin' on the dark blocks / Wearin' out the shocks, wettin' up the dashboard clock

1993, “Back Seat (of My Jeep)”, in 14 Shots to the Dome, performed by LL Cool J:

At the rear, you'll find a single, centrally mounted shock, the now-familiar single-sided swingarm and BMW's Paralever shaft-drive system, which does away with most of a shafty's chassis-jacking bugaboos.

1994, Cycle World Magazine, volume 33, number 1, page 49:

(automotive, mechanical engineering) A shock absorber (typically in the suspension of a vehicle).


lash

setting the proper valve lash for solid lifters

excessive lash in the gear train

(machining, mechanical) Looseness between fitted parts, either intentional (as allowance) or unintentional (from error or wear).


damper

en-noun

damper (countable and uncountable, plural dampers)

From damp (verb) + -er.
The name of the type of bread is first attested in 1825, and originally likely refers to damping the appetite.

In general, steel springs were stipulated for primary suspension, although rubber was accepted for auxiliary springing; hydraulic dampers were specified and the use of laminated springs ruled out.

1960 December, “The first hundred 25 kV a.c. electric locomotives for B.R.”, in Trains Illustrated, page 726:

However, complaints quickly surfaced about the ride quality of the SIG BT41 bogies, which was only cured by the fitting of additional dampers to the bogies and couplers.

2022 September 21, Ben Jones, “IC225s: the Electras go gliding on”, in RAIL, number 966, page 40:

(mechanical engineering) A shock absorber.

Something that damps or checks:
A shock absorber.


en-adj

null (comparative more null, superlative most null)

more null (comparative)
most null (superlative)

Borrowed from Middle French nul, from Latin nūllus.

In normal operation, the input cranks to both the MPCU and standby rudder actuator will rotate to provide the servo valve command to the units, and the rudder will be hydraulically moved by the MPCU. The rudder movement is in turn fed back mechanically to both the MPCU and standby actuator systems so that when the rudder surface deflects to the position commanded by the pilot, the input cranks on both of the units will be returned to their null positions. Thus, there is a geometric relationship between the rudder position, the input crank of the MPCU, the torque tube, and the input crank of the standby rudder actuator that is retained during normal operation.

2001 March 27, National Transportation Safety Board, “1.16.3 Detail Examination and Tests of Standby Rudder Actuator Input Shaft and Bearing”, in Aircraft Accident Report: Uncontrolled Descent and Collision With Terrain, United Airlines Flight 585, Boeing 737-200, N999UA, 4 Miles South of Colorado Springs Municipal Airport, Colorado Springs, Colorado, March 3, 1991, archived from the original on 2022-05-08, pages 62–63:

(mechanical engineering, of a position or setting) Neutral.


bolt

→ Irish: bolta

→ Japanese: ボルト (boruto)

→ Maltese: bolt

desctree

→ Russian: болт (bolt)
→ Azerbaijani: bolt
→ Ingrian: boltta

→ Scottish Gaelic: bolta

From Middle English bolt, from Old English bolt, from Proto-West Germanic *bolt, from Proto-Germanic *bultaz, perhaps from Proto-Indo-European *bʰeld- (“to knock, strike”). Compare Lithuanian beldu (“I knock”), baldas (“pole for striking”). Akin to Dutch and West Frisian bout, German Bolz or Bolzen, Danish bolt, Swedish bult, Icelandic bolti.

der

(military, mechanical engineering) A sliding mechanism to chamber and unchamber a cartridge in a firearm.


luff

en-verb

luff (third-person singular simple present luffs, present participle luffing, simple past and past participle luffed)

luffs (present singular third-person)
luffing (participle present)
luffed (participle past)
luffed (past)

From Old French lof. Collins English Dictionary states that this word is ultimately derived from Middle Dutch loef. Ellert Ekwall's Shakspere's Vocabulary: its etymological elements (1903) related this verb and loof instead to the East Frisian verb lofen, lufen, which would make it cognate to the French term lover.

The tower is mounted on a slewing platform, which also carries the power plant and the counterweights, while the jib is supported and luffed by fixed pendant ropes.

1999, Howard I. Shapiro, Jay P. Shapiro, Lawrence K. Shapiro, Cranes and Derricks, →ISBN, page 95:

(mechanical) To alter the vertical angle of the jib of a crane so as to bring it level with the load.


tap

The noun is derived from Middle English tappe (“hollow device for controlling the flow of liquid from a hole, cock, faucet, spigot; hole through which the liquid flows; the liquid which thus flows”), from Old English tæppa, from Proto-West Germanic *tappō, from Proto-Germanic *tappô (“a plug, tap; peg; tapering stick”), from Proto-Indo-European *deh₂p- (“to lose; to sacrifice”). Doublet of tapa.
The verb is derived from Middle English tappen (“to obtain (liquid, chiefly liquor) from a tap; to obtain and sell (liquor)”), from Old English tæppian (“to provide (a container) with a stopper; to obtain (liquid) from a tap”), and then either:
* from Old English tæppa (see above) + -ian (suffix forming verbs); or
* from Proto-Germanic *tappōną, from *tappô (noun) (see above).
Verb sense 1.3.5 (“to turn over (a playing card or playing piece) to remind players that it has already been used in that round”) alludes to the abilities or resources of the card or piece having been drawn on to the point of temporary exhaustion: see verb sense 1.3.2.

inh

The system was barely keeping pressure due to all of the ill-advised taps along its length.

(British, electrical engineering, mechanical engineering) A connection made to an electrical or fluid conductor without breaking it; a tapping.

electrical engineering
electrical engineering


motion

en-noun

motion (countable and uncountable, plural motions)

Inherited from Middle English mocioun, mocion, from Anglo-Norman motion, Middle French motion, and their etymon Latin mōtiō (“movement, motion”), related to movēre, from Proto-Indo-European *m(y)ewh₁- (“to move”).

der

perpetual motion machine of the first kind

perpetual motion machine of the second kind

[...] three 2-4-2 tank engines were secured from the Hunslet Engine Co. of Leeds. As the line began on the Quay in Bideford, the locomotives had their motion encased, as shown in the illustrations on page 414.

1939 June, “Pertinent Paragraphs: The Bideford, Westward Ho! & Appledore Railway”, in Railway Magazine, page 459:

(mechanical engineering) A piece of moving mechanism, such as on a steam locomotive.


rack

From Middle English rakke, rekke, from Middle Dutch rac, recke, rec (Dutch rek), see rekken.

Just beyond that station the first step is encountered and the rack resorted to, taking the line on a gradient of 1 in 9 over a steeply inclined bridge and through a spiral tunnel.

1950 November, H. P. White, “The Furka-Oberalp Railway”, in Railway Magazine, page 767:

The ladder-type Riggenbach rack is the one in use on both systems.

1960 December, 'Voyageur', “The Mountain Railways of the Bernese Oberland”, in Trains Illustrated, page 750:

(mechanical engineering, rail transport) A bar with teeth on its face or edge, to work with those of a gearwheel, pinion, or worm, which is to drive or be driven by it.

(mechanical engineering) A bar with teeth on its face or edge, to work with a pawl as a ratchet allowing movement in one direction only, used for example in a handbrake or crossbow.


butt

From Middle English but, butte (“goal, mark, butt of land”), from Old English byt, bytt (“small piece of land”) and *butt (attested in diminutive Old English buttuc (“end, small piece of land”) > English buttock), from Proto-West Germanic *butt, from Proto-Germanic *buttaz (“end, piece”), from Proto-Indo-European *bʰudʰnós (“bottom”), later thematic variant of Proto-Indo-European *bʰudʰmḗn ~ *bʰudʰn-, perhaps from Proto-Indo-European *dʰewbʰ- (“deep”). Cognate with Norwegian butt (“stump, block”), Icelandic bútur (“piece, fragment”), Low German butt (“blunt, clumsy”). Influenced by Old French but, butte (“but, mark”), ultimately from the same Germanic source. Compare also Albanian bythë (“buttocks”), Ancient Greek πυθμήν (puthmḗn, “bottom of vessel”), Latin fundus (“bottom”) and Sanskrit बुध्न (budhná, “bottom”), from the same Proto-Indo-European root. Related to bottom, boot.
 PIE word
 *bʰudʰmḗn

приклад

larger or thicker end of anything; blunt end

perä

end of something, often distinguished from other end

(countable, generally) An end of something, often distinguished in some way from the other end.

(mechanical) A joint where the ends of two objects come squarely together without scarfing or chamfering.


gusset

From Middle English gusset, gysset, from Old French gosset, gousset (“the hollow of the armpit”), diminutive of gose, gosse (“bean pod, hull, husk”).

(mechanical engineering) 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.

ъглова плоча

machinery: a kind of bracket, or angular piece of iron


sheaf

From Middle English scheef, from Old English sċēaf, from Proto-West Germanic *skaub, from Proto-Germanic *skauba- (“sheaf”).
Cognates
Akin to West Frisian skeaf (“sheaf”), Dutch schoof (“sheaf”), German Schaub, Old Norse skauf (“a fox's tail”). Compare further Gothic 𐍃𐌺𐌿𐍆𐍄 (skuft, “hair of the head”), German Schopf (“tuft”).


gorge

From Middle English gorge (“esophagus, gullet; throat; bird's crop; food in a hawk's crop; food or drink that has been eaten”), a borrowing from Old French gorge (“throat”) (modern French gorge (“throat; breast”)), from Vulgar Latin *gorga, *gurga, from Latin gurges (“eddy, whirlpool; gulf; sea”), possibly from Proto-Indo-European *gʷerh₃- (“to devour, swallow; to eat”). The English word is cognate with Galician gorxa (“throat”), Italian gorga, gorgia (“gorge, ravine; (obsolete) throat”), Occitan gorga, gorja, Portuguese gorja (“gullet, throat; gorge”), Spanish gorja (“gullet, throat; gorge”). Doublet of gour.

cog

LL-Q1860 (eng)-I learned some phrases-gorge.wav

But as the rope muſt lead the pulley, or the pulley the rope, when there is room to apprehend that the rope may not ſlide upon the pulley, the gorge is hollowed in the form of an angle, or ſtuck with points,[…].

1761 May, “Elements of Philosophy, […] Illustrating the Mechanical Powers of Balances, Levers, Pulleys, &c. and Some Observations as to the Center of Gravity and Equilibres. [Of Pulleys and Moufles or Mousled Pulleys.]”, in The Universal Magazine of Knowledge and Pleasure: […], volume CXCV, number XXVIII, London: Published […] [b]y John Hinton […], →OCLC, page 256, column 1:

A cord, in passing round a pulley, lies in a groove, sometimes called the gorge of the pulley; if the object of the pulley is merely to support, guide, or strain the cord, the gorge may be considerably wider than the cord; if the pulley is to drive or to be driven by the cord, so as to transmit motive power, the gorge must in general fit the cord closely, or even be of a triangular shape, so as to hold it tight.

1869, William John Macquorn Rankine, “Of Elementary Combinations in Mechanism”, in A Manual of Machinery and Millwork, London: Charles Griffin and Company, […], →OCLC, part I (Geometry of Machinery), section V (Connection by Bands), paragraph 172, page 187:

(mechanical engineering) The groove of a pulley.


beam

From Middle English beem, from Old English bēam (“tree, cross, gallows, column, pillar, wood, beam, splint, post, stock, rafter, piece of wood”), from Proto-West Germanic *baum, from Proto-Germanic *baumaz (“tree, beam, balk”), from Proto-Indo-European *bʰew- (“to grow, swell”). Cognate with West Frisian beam (“tree”), Saterland Frisian Boom (“tree”), Dutch boom (“tree”), German Low German Boom (“tree”), German Baum (“tree”), Luxembourgish Bam (“tree”), Albanian bimë (“a plant”). Doublet of boom.
The original English meaning of beam ("tree") is preserved in some compound words such as quickbeam.
The verb is from Middle English bemen, from Old English bēamian (“to shine, to cast forth rays or beams of light”), from the noun.

inh

The doubtful beam long nods from side to side.

1714, Alexander Pope, “The Rape of the Lock”, in The Works of Mr. Alexander Pope, volume I, London: […] W[illiam] Bowyer, for Bernard Lintot, […], published 1717, →OCLC, canto V:

(mechanical) The crossbar of a mechanical balance, from the ends of which the scales are suspended.

(mechanical) In steam engines, a heavy iron lever having an oscillating motion on a central axis, one end of which is connected with the piston rod from which it receives motion, and the other with the crank of the wheel shaft.


detonation

en-noun

detonation (countable and uncountable, plural detonations)

From French détonation; equivalent to detonate + -ion.

(mechanical engineering) Engine knocking, a type of improper combustion in gasoline piston engines.

detonáció

mechanical engineering: engine knocking, a type of improper combustion in gasoline piston engines


channel

→ Japanese: チャンネル (channeru)

→ Korean: 채널 (chaeneol)

→ Welsh: sianel

From Middle English chanel (also as canel, cannel, kanel), a borrowing from Old French chanel, canel, from Latin canālis (“groove; canal; channel”). Doublet of canal.

kanal

communication: single path provided by a transmission medium via physical separation

kanal

broadcasting: specific radio frequency or band of frequencies

The channel is not very efficient as a beam or column when used alone, but built-up members may be constructed of channels assembled together with other structural shapes and connected by rivets or welds.

1960, “Structural Shapes”, in Construction Materials, Concrete Construction, and Engineer Computations, U.S. Government Printing Office:

(construction, mechanical engineering) A structural member with a cross section shaped like a squared-off letter C.


swivel

en-noun

swivel (countable and uncountable, plural swivels)

From Middle English swyvel, swivel, from a derivative of Old English swīfan (“to revolve”), + -el, an instrumental suffix, equivalent to swive + -el.

The patter of feet, and clatter of strap and swivel, seemed to swell into a bewildering din, but they were almost upon the fielato offices, where the carretera entered the town, before a rifle flashed.

1907 January, Harold Bindloss, chapter 7, in The Dust of Conflict, 1st Canadian edition, Toronto, Ont.: McLeod & Allen, →OCLC:

(mechanical) A piece, such as a ring or hook, attached to another piece by a pin, in such a manner as to permit rotation about the pin as an axis.


chuck

chuck (countable and uncountable, plural chucks)

1824, Royal Society of Arts (Great Britain), Transactions, Volume 42, page 88,
I have had a chuck of this kind made in brass with the cones of iron, but it is cumbrous and expensive, and does not answer so well, owing to the surface of the iron offering less resistance to the work turning within it. This, perhaps, might be remedied by roughing; but I think the chuck is much better in wood, as it can be made by any common turner at a trifling expense, and possesses more strength than can possibly be required.

Iron and steel in contact with magnets retain some of the magnetism, which is sometimes more or less of a nuisance in getting small work off the chucks.

1912, Fred Herbert Colvin, Frank Arthur Stanley, American Machinist Grinding Book, page 322:

2003, Julie K. Petersen, “chuck”, entry in Fiber Optics Illustrated Dictionary, page 181,
A fiber optic splicing device may be equipped with V-grooves or chucks to hold the two pieces of fiber optic filament to be spliced. If it has chucks, they are typically either clamping chucks or vacuum chucks.

The first step in preparing a test specimen with the FlexPrepᵀᴹ is to secure the gyratory specimen in the chuck of the machine.

2008, Ramon Francis Bonaquist, NHCRP Report 614: Refining the Simple Performance Tester for Use in Routine Practice, page 30:

(mechanical engineering) A mechanical device that holds an object firmly in place, for example holding a drill bit in a high-speed rotating drill or grinder.


idle

From Middle English idel, ydel, from Old English īdel (“idleness”), from the adjective (see above).

a lumpy idle

A slight valve tap was audible at idle but was not noticeable otherwise.

(mechanical engineering) The lowest selectable thrust or power setting of an engine.


bearing

From Middle English bering, beringe, berynge, equivalent to bear + -ing.

(mechanical engineering) A mechanical device that supports another part and/or reduces friction.


journal

journals (plural)
journall (alternative)

From Middle English journal, from Anglo-Norman jurnal (“daily”), from Old French jornel (“day”) (French journal), from Latin diurnālis, from diurnus (“of the day”). Doublet of diurnal and the journal from French.

(mechanical engineering) the part of a rotating shaft that rests on the bearing


top dead center

(mechanical) A position in the cycle of a piston engine wherein the piston is at the topmost point in its stroke. In a four-stroke cycle, TDC occurs twice: at the end of the compression stroke and at the end of the exhaust stroke.

(mechanical) The reference mark on a flywheel (and engine block) indicating the engine is in this position, when aligned.


dipstick

en-verb

dipstick (third-person singular simple present dipsticks, present participle dipsticking, simple past and past participle dipsticked)

dipsticks (present singular third-person)
dipsticking (participle present)
dipsticked (participle past)
dipsticked (past)
dip-stick (alternative)

If one of the fuel gauges is inoperative (flight is not permitted if both have failed), the tanks have to be dipsticked before and after each fueling to confirm the aircraft's fuel status.

(mechanical engineering, transitive) To measure the level of a fluid using a dipstick.


documentation

en-noun

documentation (countable and uncountable, plural documentations)

From document + -ation or Medieval Latin documentātio.

(computing, mechanical engineering) Documents that explain the operation of a particular machine or software program.

dokumentimi

documents that explain the operation of a particular machine or software program


bushing

From bush (“metal lining of the axle hole of a wheel or touch hole of a gun”) + -ing.

suf

(mechanical engineering) A type of bearing, a cylindrical lining designed to reduce friction and wear inside a hole, often used as a casing for a shaft, pin or hinge.

průchodka

mechanical engineering: type of bearing to reduce friction

(mechanical engineering) An elastic bearing used as a type of vibration isolator, commonly made of rubber. An interface between two parts, damping the movement and the energy transmitted.

(mechanical engineering) A threaded bushing: a fastener element that is inserted into an object, usually to add a threaded hole in a softer or thin material.

kierreholkki

mechanical engineering: threaded bushing


shock absorber

LL-Q1860 (eng)-Flame, not lame-shock absorber.wav

Hydraulic shock absorbers are used to damp out vertical and lateral oscillations.

1960 February, “The first of London's new Piccadilly Line trains is delivered”, in Trains Illustrated, page 93:

(mechanical engineering) A mechanical device designed to smooth out or damp any sudden shock impulse and dissipate kinetic energy; usually consists of a combination of a spring and a dashpot.


induction

en-noun

induction (countable and uncountable, plural inductions)

Inherited from Middle English induction, from Old French induction, from Latin inductiō, from indūcō (“I lead”). By surface analysis, induct + -ion or induce + -tion.

(mechanical engineering) The delivery of air to the cylinders of an internal combustion piston engine.


retainer

(rail transport, mechanical engineering) A retaining valve.


mechanical advantage

mechanical advantage (countable and uncountable, plural mechanical advantages)

[…]and it will always be found, that the mechanical advantage of the wedge may be ascertained by comparing its perpendicular elevation with its base.

1825, Maria Edgeworth, Richard Lovell Edgeworth, Works of Maria Edgeworth, Volume 1: Practical Education, Samuel H. Parker, page 304:

In the case of a lever with a mechanical advantage of 10 the effort has to move ten times as far as the load. This is the price which must always be paid for a mechanical advantage. Any machine which is designed to have a high mechanical advantage must also have a high velocity ratio. In fact, 'what is gained in force is lost in speed'.

1965, A. E. E. McKenzie, General Physics, Cambridge University Press, page 76:

Mechanical advantage is a ratio of like quantities and therefore has no units.

2005, Robert Michael Boyce, Arnold Masterman, Plumbing: A Practical Guide for Level 2, Nelson Thornes, page 131:

(mechanical engineering) The ratio of the output force produced by a machine (especially a simple machine) to the applied input force.


overdrive

overdrive (countable and uncountable, plural overdrives)

From over- + drive, originally referring to gear ratios over 1:1.

/ˌəʊvə(ɹ)ˈdɹaɪv/

/ˈəʊvə(ɹ)ˌdɹaɪv/

(engineering, mechanical) A gear ratio higher than 1:1: one in which a single revolution of the driving element corresponds to more than one revolution of the driven element.


planer

Besides the usual run of machines, planers, millers, automatics, centre lathes, cranes, etc., there were several power stations, the rolling mills for strip material and for 60 ft. rails, and all the steel furnaces with their complicated systems of flues. If variety is the spice of life, then there was plenty here.

1944 November and December, A Former Pupil, “Some Memories of Crewe Works—II”, in Railway Magazine, page 341:

(mechanical engineering) A large machine tool in which the workpiece is traversed linearly (by means of a reciprocating bed) beneath a single-point cutting tool. (Analogous to a shaper but larger and with the workpiece moving instead of the tool.) Planers can generate various shapes, but were most especially used to generate large, accurate flat surfaces. The planer is nowadays obsolescent, having been mostly superseded by large milling machines.


ignition

ignition (countable and uncountable, plural ignitions)

(automotive, mechanical engineering) A system for activating combustion in a combustion engine.

запалване

system for activating combustion in an engine


sprocket

sprockets (plural)
splocket (alternative)

Unknown. First attested in the 16th century. Perhaps related to Italian rocchetto (“spool”), spoletta (“spool”), sprone (“spur”), or English spoke, spike, spur.

(mechanical engineering) A toothed wheel that enmeshes with a chain or other perforated band.


braked

On most aircraft, the mainwheels are braked, but the nosewheel or tailwheel is not.

(mechanical engineering, rail transport, aviation, of a wheel) Equipped with brakes (the vehicle-stopping devices).


run-in

en-adj

run-in (not generally comparable, comparative more run-in, superlative most run-in)

more run-in (comparative)
most run-in (superlative)

A well run-in engine is likelier to consume less crankcase oil over the course of its working life.

participial adjective
participial adjective

(participial adjective; mechanical, engineering) (sometimes comparable) Having been run in to seat the parts.


flywheel

They were fitted with flywheels 25 ft. in dia. and weighing 50 tons each. The energy stored in such flywheels is very great, and in this case was of the order of 7,000,000 lb./ft. each.

1955 January, Charles E. Lee, “The Glasgow Underground Railway”, in Railway Magazine, page 24:

As on Nos. 20001-3, the motor and generator armature shafts of the new locomotive each carry a heavy flywheel to provide kinetic energy and help maintain the speed of the motor-generator set during interruptions of supply, as at breaks in the continuity of the conductor rail.

1959 March, “The 2,500 h.p. electric locomotives for the Kent Coast electrification”, in Trains Illustrated, page 123:

(mechanical engineering) 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.


cotter

cotter
cotter (pin)
cotter pin
split pin

The chains are secured to each end of the cast-iron arches by cotters.

1949 November and December, “Notes and News: The High Level Bridge, Newcastle”, in Railway Magazine, page 407:

(mechanical engineering) A pin or wedge inserted through a slot to hold machine parts together.


quill

LL-Q1860 (eng)-Naomi Persephone Amethyst (NaomiAmethyst)-quill.wav

From late Middle English quyl, which is first attested in the early 15th century with the meanings "fragment of reed" and "shaft of a feather", probably from Low German and Middle Low German quiele, possibly ultimately from Proto-Indo-European *gʷelH- (“to pierce, stick”).
Compare Middle High German kil (“large feather, quill”), which is derived from the Low German term.

cog

The motors are attached to the bogie frames so as to be fully springborne, and drive through quills and flexible couplings to the wheels.

1952 September, “A Landmark in French Electrification”, in Railway Magazine, page 593:

(mechanical engineering) A quill drive, having a hollow shaft with another movable shaft inside it.


lockup

(mechanical engineering) A condition in which one or more of a vehicle's wheels suddenly cease to rotate due to the application of excessive brake torque, causing the affected wheel(s) to skid.


runout

en-noun

runout (countable and uncountable, plural runouts)

We determined that inaccuracy was caused by a large amount of tool runout.

(mechanical engineering) Deviation of the axis of rotation of a rotating object (especially a milling cutter or workpiece) relative to that object's centerline; the specific amount of deviation.


gear train

gear trains (plural)
geartrain (alternative)

(mechanical engineering) A system of interconnected gears.


interphase

interphase (countable and uncountable, plural interphases)

Strain transfer will inevitably occur through an interphase between the fibres and the matrix so this region is of obvious importance to the performance of a composite.

2002, M.S. Found, Experimental Techniques and Design in Composite Materials, →ISBN:

This book addresses several aspects and methodologies related to the micromechanics of contact and interphase layers, ranging from the rigorous method of asymptotic expansions to the practical application of the finite element method.

2007, S. Stupkiewicz, Micromechanics of Contact and Interphase Layers, →ISBN, page 171:

The metal part of the interphase probably consists of several layers of ions embedded in the electron "cloud" of the metal.

2012, Ilana Fried, The Chemistry of Electrode Processes, →ISBN, page 66:

(mechanical engineering, countable) An indistinct region in the interface between two substances in composite materials.


pinion

1844, Edgar Allan Poe, The Premature Burial
A certain period elapses, and some unseen mysterious principle again sets in motion the magic pinions and the wizard wheels.

The usual front sprocket has teeth, which which mesh into a pinion on a shaft that carries power to the wheel through a pair of pinions at the rear.

1898, Alexander Schwalbach, Julius Wilcox, “The Chainless Wheel”, in The Modern bicycle and its accessories; a complete reference book for rider, dealer, and maker, New York: The Commercial advertiser association, page 10:

The spiral bevel pinion has 19 teeth, a diametral pitch of 6.940 teeth/inch, a face width of 1.28 inch, a bevel angle of 15 degrees 16 minutes, and a spiral angle of 30 degrees left hand, clockwise.

2003, Spiral Bevel Pinion Crack Detection in a Helicopter Gearbox, page 5:

(mechanical engineering) The smallest gear in a gear train.


run in

en-adj

run in (not generally comparable, comparative more run in, superlative most run in)

more run in (comparative)
most run in (superlative)

The engine should be well run in before its heavy working life begins.

Behaviour patterns now thoroughly "run in", and financial stringencies, appear to impose sharp limits on the prospects of success here.

1978, European Conference of Ministers of Transport, International Symposium on Theory and Practice in Transport Economics The Contribution of Economic Research to Transport Policy Decisions, page 64:

In addition to the above, the systems analyst should go on shift with the users for the first few days or longer until the system is thoroughly run in.

1978, John E. Bingham, Garth W.P. Davies, A Handbook of Systems Analysis, page 35:

Now that the engine is thoroughly run in, our overall fuel economy is creeping toward the high 22-mpg range.

1993 December, T.S., “Long-Term Test cars”, in Popular Mechanics, volume 170, number 12, page 112:

Under no circumstances run a new motor at high speed until it has covered several hundred miles and is thoroughly “run in.”

2012, Victor W. Page, Early Motorcycles: Construction, Operation and Repair, page 487:

Alternative form of run-in (adjective) (styled open when in predicative position)


utters

From utter + -s (suffix forming pluralia tantum, and third-person singular simple present indicative forms of verbs). The noun is imitative of the sound of a tool repeatedly striking the surface of an object.

affix

(mechanical engineering) Unwanted depressions or other marks on the surface of an object caused when a tool is pressed too hard or vibrates against the surface.


brake shoe

brake shoes (plural)
brakeshoe (alternative)

The rotating action of the brake drum tends to pull one brake shoe harder into contact. This is known as self-servo action. It occurs on the brake shoe, which is after the wheel cylinder, in the direction of wheel rotation.

2014, Tom Denton, Automotive Technician Training: Entry Level 3: Introduction to Light Vehicle Technology, Routledge, →ISBN, page 224:

(mechanical engineering) An element of a drum brake into which the friction-producing brake lining is attached.


retarder

LL-Q1860 (eng)-Flame, not lame-retarder.wav

[...] unlike the latest British yards, Gremberg has only primary retarders, manually operated, a method that the hump operators apparently prefer to electro-pneumatic control because they can grade the braking pressure more accurately by feel.

1961 April, G. Freeman Allen, “The "Rheingold" goes via Cologne”, in Trains Illustrated, page 237:

(mechanical engineering) A device for slowing down large trucks, lorries, buses, shunted railway wagons.


RCP

reinforced concrete pipe
w:reinforced concrete pipe

(mechanical engineering) Initialism of reinforced concrete pipe.


drivetrain

drivetrains (plural)
drive train (alternative)

If you wait until later, your drivetrain is liable to misshift under the hard pedaling load.

1990, Joe Kita, Bicycling Magazine's New Bike Owner's Guide, page 28:

(mechanical engineering) The mechanical parts of the powertrain, the gears and shafts, that connect the engine to the wheels in a vehicle.


dropping point

(mechanical engineering) The temperature at which a grease passes from a semi-solid to a liquid state under specific test conditions.

Tropfpunkt

temperature at which a grease becomes liquid


diesel engine

LL-Q1860 (eng)-Flame, not lame-diesel engine.wav

internal combustion engine
internal combustion engine

(mechanical engineering) An internal combustion engine of piston engine type that operates using the Diesel cycle, with fuel being sprayed into the hot, high-pressure air in the combustion chamber at the end of the compression stroke.

(usually automotive, transport) Such an engine that burns diesel (diesel fuel).


handbrake

handbrakes (plural)
hand brake (alternative)

On arrival at Spiez, the locomotive (No. 206) was immediately uncoupled and drew ahead to enable an Italian through coach from Interlaken to Milan to be loose shunted (with passengers aboard and controlled by means of its handbrake) on to the front of the train.

1953 August, J. G. Click, “The Lötschberg Railway”, in Railway Magazine, page 515:

(mechanical engineering, automotive, rail transport) A brake in a vehicle, set by hand, and usually locking on until released by hand, enabling its use when parked.

(mechanical engineering, automotive, rail transport) 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.


broken in

en-adj

broken in (not generally comparable, comparative more broken in, superlative broken in)

more broken in (comparative)
broken in (superlative)

The engine should be well broken in before its heavy working life begins.

(participial adjective; mechanical, engineering) (sometimes comparative) Having been broken in to seat the parts.


wastegate

(mechanical engineering, automotive, aviation) A valve that allows exhaust gases to bypass an engine's turbocharger, in order to keep from overspeeding the turbocharger rotor or driving the boost pressure high enough to risk engine knocking or detonation.


barreling

en-noun

barreling (countable and uncountable, plural barrelings)

barrelings (plural)
barrelling (alternative)

(mechanical engineering) A defect in which a testpiece is deformed into a barrel-like shape.


boat lift

boat lifts (plural)
boatlift (alternative)

(mechanical engineering) A mechanism used for raising and lowering boats on a canal vertically from one water level to another, while keeping them afloat.


pushrod

pushrods (plural)
push rod (alternative)

LL-Q1860 (eng)-Flame, not lame-pushrod.wav

The cam-within-a-cam concept has existed for decades, but perfecting it for production might just add another decade to the life of the pushrod engine.

2007 January 14, Don Sherman, “Making Modern Horsepower the Old-Fashioned Way”, in New York Times:

(mechanical engineering) A rigid reciprocating rod that, by its movement, transmits force to actuate a mechanism.

(automotive) A rod in a piston engine that actuates rocker arms above the cylinder head.

An internal-gear hub with a hollow axle may be re-oiled by removing the pushrod or indicator spindle and squirting oil into the end of the axle.

2000, 2008, “Internal-Gear Hubs”, in Sheldon Brown's Bicycle Technical Info, archived from the original on 2019-08-23:

Push Rod (81.85 mm) for Axle Length 168 mm

2018, “NEXUS 3-SPEED HUB w/Coaster Brake”, in Manuals & Technical Documents:

(cycling) A rod in an internal gear hub that actuates the shifting mechanism.

On 17 August 2005, a Saab 2000, at the ramp, with controls locked, was subjected to jet blast of around 126 kt (233 km/h) from a passing B747. This resulted in the bending of the left aileron control pushrod, causing it to fail at the time of takeoff. The crew had to make an emergency landing.

2013 May 4, Bureau d'Enquêtes et d'Analyses pour la sécurité de l'aviation civile, “1.16.9.5: Known events”, in Report: Accident on 9 August 2007 off the coast of Moorea (French Polynesia) to the DHC6-300 registered F-OIQI operated by Air Moorea, archived from the original on 2021-01-31, page 55:

(aviation) A rod used in the transmission of flight control inputs to an aircraft's control surfaces.


crosshead

All the Connor characteristics are seen in this locomotive: sharply inclined cylinders let into the side framing, which was slotted to expose the crosshead; […].

1945 January and February, “Notes and News: An Early Caledonian 2-4-0”, in Railway Magazine, page 47:

(mechanical engineering) A metal beam that connects a piston to a connecting rod in an engine.


bottom out

en-verb

bottom out (third-person singular simple present bottoms out, present participle bottoming out, simple past and past participle bottomed out)

bottoms out (present singular third-person)
bottoming out (participle present)
bottomed out (participle past)
bottomed out (past)

The hard landing caused the oleos to bottom out and the gear struts collapsed.

(mechanical engineering, of a suspension or similar device) To strike the lower mechanical stop and lose the ability to buffer further downward motion.


inlead

inlead (third-person singular simple present inleads, present participle inleading, simple past and past participle inled)

inleads (present singular third-person)
inleading (participle present)
inled (participle past)
inled (past)

From Middle English inleden (“to lead or bring in, introduce”), from Old English inlǣdan (“to lead in, bring in, introduce, conduct”), equivalent to in- + lead. Cognate with Dutch inleiden (“to initiate; introduce”), German einleiten (“to initiate; introduce”), Danish indlede (“to introduce”), Swedish inleda (“to introduce”).

cog

Helge Lundholm
new afferent or inleading processes might be set up tending, themselves, towards the mathematical point of interaction

(transitive, mechanical and electrical) To lead into; conduct.


inlead

a cathode inlead

inlead tube

(mechanical and electrical) A conduit, channel or wire leading into a container or device.


keyway

Near-synonyms: keyseat, groove

(mechanical) The recessed part of a keyed joint, in which the key resides.


air cell

(mechanical engineering) A prechamber in an indirect injection internal combustion engine.


odontograph

(historical, dentistry, mechanical engineering) An instrument for marking or laying off the outlines of teeth of gear wheels.


bevel gear

Each axle has its own final drive two-step reduction, a bevel gear set and a spur gear set which drives the axle. Of these, the spur gears take most of the stress and the bevel gears provide optimum reduction at high speed and low torque—an arrangement which makes for easier assembly and reduced load for the bevel gears.

1962 June, “Beyond the Channel: U.S.S.R.: A 3,000 h.p. diesel-hydraulic from MaK”, in Modern Railways, page 416:

(mechanical engineering) A kind of gear in which the two wheels working together lie in different planes and have their teeth cut at right angles to the surfaces of two cones whose apices coincide with the point where the axes of the wheels would meet.


milling cutter

(mechanical engineering) A rotary cutting tool typically used in milling machines.


bellcrank

bellcranks (plural)
bell crank (alternative)

From bell + crank, because of its original use in changing the vertical pull on a rope to a horizontal pull on the striker of a bell.

(mechanical engineering) A type of crank that changes motion through an angle, typically 90 or 180 degrees.


four-way cock

(mechanical) 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.


bollarding

An excessive film thickness, on the other hand, produces bollarding in which the diameter of the specimen becomes bigger at the ends than at the middle.

2006, Jagabanduhu Chakrabarty, Theory of Plasticity:

(mechanical engineering) A defect in which a testpiece is deformed into a bollard-like shape.


Vickers hardness

en-noun

Vickers hardness (countable and uncountable, plural Vickers hardnesses)

Developed at Vickers Limited, founded by miller Edward Vickers and his father-in-law George Naylor in 1828.

(mechanical engineering) The hardness of a material according to the Vickers hardness test, based on its ability to resist plastic deformation from a standard source.


backshell

backshells (plural)
back shell (alternative)

(mechanical) Part of an electrical conductor or other electrical device, such as a cable clamp or adapter, that is threaded onto the rear connector accessory threads of plug or receptacle connectors to make up the total connector assembly.


rodding

rodding (countable and uncountable, plural roddings)

Anything that reverses the direction of movement in a length of point rodding will act as a compensator over an equal length on each side of it; […].

1944 July and August, “The Why and the Wherefore: Point-Rod Compensators”, in Railway Magazine, page 256:

(mechanical engineering) A system of rods etc. used for movement.


VSV

VSV (countable and uncountable, plural VSVs)

(aviation, mechanical engineering) Initialism of variable stator vane.


odontometer

(mechanical engineering) An odontograph.


trunk piston

(mechanical engineering) In a single-acting engine, an elongated hollow piston, open at the end, in which the end of the connecting rod is pivoted. The piston rod, crosshead and stuffing box are thus dispensed with.


cotterless

(mechanical engineering) Without a cotter.


blastpipe

blastpipes (plural)
blast-pipe (alternative)
blast pipe (alternative)

From blast (“forcible stream of gas, etc., from an orifice; exhaust steam from an engine”) + pipe.

compound

[W]ith this arrangement the cylinders are cast separately from the saddle, and bolted to the frames on each side with a fabricated stiffener between the frames. This stiffener is carried up to form the saddle for the smokebox, and within it is fitted the exhaust pipes from the cylinders to the blast pipe.

1944 November–December, “Modified G.W.R. ‘Hall’ Class Locomotives”, in The Railway Magazine, London: Tothill Press, →ISSN, →OCLC, page 350:

By this time the "King" had been fitted with four-row superheater, double blastpipe and chimney, and all the later modifications effected by Swindon in these engines, to which they responded so well with the poorer quality of fuel of their last years.

1963 September, Cecil J. Allen, “Locomotive Running Past and Present”, in Modern Railways, Shepperton, Surrey: Ian Allan Publishing, →ISSN, →OCLC, page 186:

(mechanical engineering, rail transport) A pipe forming part of the exhaust system of a steam locomotive that discharges exhaust steam from the cylinders up into the smokebox beneath the chimney in order to increase the draught through the firebox; this speeds up the release of smoke through the chimney.


bottom dead center

(mechanical) A position in the cycle of a piston engine wherein the piston is at the bottommost point in its stroke. In a four-stroke cycle, BDC occurs twice: at the end of the intake stroke and at the end of the power stroke.

(mechanical) The reference mark on a flywheel (and engine block) indicating that the engine is in this position, when aligned.


overshift

/ˈəʊvə(ɹ)ˌʃɪft/

/ˌəʊvə(ɹ)ˈʃɪft/

Back off second speed, overshift stop screw slightly, and determine that speed poppet is seated in notch. Tighten screw to permit a very slight overshift of lever to rear.

1971, Chilton's Auto Repair Manual, 1940-1953, page 624:

One other derailleur problem I should mention is that of chain overshift or overshooting the gear you select.

1982, Eugene A. Sloane, Eugene A. Sloane's bicycle maintenance manual, page 88:

Damaging chain overshifts from misadjusted derailleurs can occur after wheel swaps, but they're avoidable.

2010, Todd Downs, The Bicycling Guide to Complete Bicycle Maintenance & Repair, →ISBN, page 52:

(mechanical engineering) A misalignment resulting from shifting gears too far.


overshift

en-verb

overshift (third-person singular simple present overshifts, present participle overshifting, simple past and past participle overshifted)

overshifts (present singular third-person)
overshifting (participle present)
overshifted (participle past)
overshifted (past)

/ˈəʊvə(ɹ)ˌʃɪft/

/ˌəʊvə(ɹ)ˈʃɪft/

The objects of the invention are to automatically throw off the power and to apply the brake in such a manner that it will have no tendency to produce too sudden a stop or to overshift and release before the car has stopped.

1905, Specifications and Drawings of Patents Issued from the United States Patent Office for January 1905:

Back off second speed, overshift stop screw slightly, and determine that speed poppet is seated in notch.

Shift down rapidly to the smallest rear cog. The chain must not overshift so it rubs on the spokes or on the spoke protector as you shift up

1991, Eugene A. Sloane, Sloane's Complete Book of All-terrain Bicycles, →ISBN, page 39:

(mechanical engineering) To overshoot when changing gears.


undershift

Briefly, in the invention, the shift mechanism is incorporated into the handlebar stem, a positive push-pull type cam mechanism is provided for actuating the rear derailleur, undershift and overshift is prevented to eliminate chain "jump off", and the device can be shifted with the bicycle standing still.

1981, H Ross, Single lever 10-speed bicycle shifter - US Patent 4,279,174:

(mechanical engineering) A misalignment resulting from failure to shift gears far enough.


undershift

undershift (third-person singular simple present undershifts, present participle undershifting, simple past and past participle undershifted)

undershifts (present singular third-person)
undershifting (participle present)
undershifted (participle past)
undershifted (past)

Since it is easy to undershift or overshift, each lever must be adjusted manually to its optimal position on the cog or chainring.

1990, Norman D. Ford, Keep on pedaling: the complete guide to adult bicycling, page 194:

(mechanical engineering) To undershoot when changing gears.


hydrostatic lock

en-noun

hydrostatic lock (countable and uncountable, plural hydrostatic locks)

When hydrostatic lock is suspected or exists, stop cranking immediately and notify unit maintenance.

1992, US Department of the Army, Operator's Manual: Armored Reconnaissance/airborne Assault Vehicle, Full-Tracked 152-mm Gun/Launcher:

If the engine does not rotate, it may be seized due to its being operated with no oil, broken engine components, or hydrostatic lock.

2014, Barry Hollembeak, Today's Technician, →ISBN:

Cavitated liners can also leak combustion gases into the cooling system, but they tend to produce hydrostatic locks after the engine is shut down when hot.

2015, Gus Wright, Fundamentals of Medium/Heavy Duty Diesel Engines, →ISBN, page 328:

(mechanical engineering, usually uncountable) A condition that arises when a device which compresses gases seizes up because of the infiltration of liquid, which prevents further compression.


air hose

air hoses (plural)
airhose (alternative)
air-hose (alternative)

(mechanical engineering) A hose for conveying compressed air within a pneumatic system.


ECTS

(mechanical engineering) Initialism of engine coolant temperature sensor.


torque converter

torque converter (plural torque converters)

The eight-cylinder Rolls-Royce diesel engines drive through "Twin Disc" torque converters up to a speed of some 46 m.p.h., when the drive automatically changes to direct coupling and the torque converter is disengaged.

1959 December, “Diesel multiple-units on the St. Pancras-Bedford service”, in Trains Illustrated, page 588:

(mechanical engineering) A device that converts the rotational output of a prime mover into work by driving a rotational load. A torque converter functions as a clutch and reduction gear to allow loose coupling between the driver and the driven, letting the drive (such as a motor or engine) rotate at different speeds from the load (such as a wheel).


vapor lock

vapor lock (countable and uncountable, plural vapor locks)

vapor locks (plural)
vapour lock (alternative)

(mechanical engineering) A problem mostly affecting gasoline-fueled internal combustion engines, where the liquid fuel changes state from liquid to gas while still in the fuel delivery system, reducing the pump pressure and causing transient power loss or complete stalling.

The Coast Guard Marine Safety Center modeled and analyzed the lube oil levels in the main engine sump in a static condition. The safety center concluded that with 1,226 gallons of oil in the sump, as was likely on the accident voyage, and a 5-foot trim by the stern (0.4°), the bellmouth opening of the line leading from the sump to the lube oil pumps would break the oil's surface at an 18° port list. At that point, the bellmouth would no longer be submerged in the lube oil and air would enter the pumps, causing a vapor lock.

2017 December 12, National Transportation Safety Board, “2.4.1 Loss of Propulsion”, in Marine Accident Report: Sinking of US Cargo Vessel SS El Faro, Atlantic Ocean, Northeast of Acklins and Crooked Island, Bahamas, October 1, 2015, archived from the original on 2022-05-15, page 185:

(especially mechanical engineering) Synonym of air lock.


deadband

deadband (countable and uncountable, plural deadbands)

deadbands (plural)
dead zone (alternative)
neutral zone (alternative)

The steering system has so much backlash that it takes a full rotation of the wheel to exit its deadband and affect the steering.

(mechanical engineering) Backlash in a mechanical system.


shaft horsepower

(mechanical engineering) In an engine, the power measured in horse power delivered to a rotating shaft, which could be in a turbine, or transmission.


blisk

(aviation, mechanical engineering) An aircraft turbine engine rotor that has integral blades.


cambox

André took off the cambox covers on a Chapelon and described in detail the action of the valves and the method of setting.

1961 March, ""Balmore"", “Driving and firing modern French steam locomotives”, in Trains Illustrated, page 149:

(mechanical engineering) A metal "box" that houses cams, in the same manner that a gearbox houses gears.


diesel-hydraulic

In November 1959, a paper entitled "The Swindon-built Diesel-Hydraulic Locomotive" was presented to the Institute of Locomotive Engineers by Mr. G. E. Scholes and it contained some very interesting figures. One set was a comparison between the mileages achieved during a period of the first five months in 1959 by "King" and "Castle" 4-6-0s and "Britannia" 4-6-2s and those of D800 to D805, the first of the Swindon-built 2,000 h.p. diesel-hydraulic locomotives of the "Warship" class, then brand new and subject to the teething troubles of all such complicated units in the earliest stages of their use.

1961 March, Cecil J. Allen, “Locomotive Running Past and Present”, in Trains Illustrated, page 153:

The elimination of vacuum-braked wagons would be slowed down, and the Western Region's flirtation with diesel-hydraulic locomotives was questioned.

2023 March 8, Howard Johnston, “Was Marples the real railway wrecker?”, in RAIL, number 978, page 52:

(mechanical engineering) Powered by a diesel engine via a hydraulic transmission.


cardan shaft

cardan shafts (plural)
Cardan shaft (alternative)

Each axle of every 82ft-long car is powered by a 170kW traction motor with flexible cardan shaft drive.

1963 January, “New in Japan: Tokaido Line trials”, in Modern Railways, page 44:

(mechanical engineering) A driveshaft with a universal joint at one or both ends.


axle-hung

It had been difficult to find space for disc brakes when axle-hung motors were used, but the length of motors was being reduced and one of the advantages of this might be the possibility of fitting disc brakes.

1964 January, “The adhesion problem”, in Modern Railways, page 38:

(mechanical engineering) Of a traction motor, mounted on the axle it drives.


side play

The leading end of the coupling rod is provided with ½-in. side-play and self-aligning bearings to take the sharp curves on the dock sidings, which have a radius of 170 ft. The bogie has a side-play of 5 in.

1939 June, Lieut.-Colonel K. H. Reed, “Locomotives of the B.C.D.R.”, in Railway Magazine, pages 416, 422:

Side play is allowed on the middle driving axle and its motor has freedom to move sideways with the axle, but the motors on the two outer driving axles are resiliently held irrespective of movement of the axles, which have reduced side-play.

1959 June, “The first "Peak" class 2,300 h.p. diesel-electric locomotive for B.R.”, in Trains Illustrated, page 296:

(mechanical engineering) Lateral freedom of movement in moving parts.


drop hammer

On embankments these troughs are supported by piles driven into the ground and recent practice has been to drive them in by a drop hammer, manually operated from a railway wagon, [...].

1961 November, “Talking of Trains: The North Eastern's new rail-mounted piling unit”, in Trains Illustrated, page 646:

(mechanical engineering) A heavy weight that is raised and then allowed to drop, as used for piledriving and drop-forging.


reverse gear

Reverse gear, air-operated, is incorporated in the transmission.

1962 April, “Beyond the Channel: Western Germany: The Henschel 4,000 h.p. V320 diesel”, in Modern Railways, page 274:

It's a chance to get transport investment in this country out of reverse gear - a chance to end paper promises.

2021 October 6, Paul Stephen, “Network News: Labour: build HS2 and NPR and end "paper promises"”, in RAIL, number 941, page 25:

A gear in a vehicle transmission which, when selected, makes the vehicle to move in the direction the driver has the back.

A gear fitted to a machine which allows it to run in the opposite direction to normal.


(mechanical engineering) An internal combustion engine with sixteen cylinders in two banks of eight in a V-formation.


wet heater

(military, mechanical engineering) A torpedo engine where water is injected into the combustion chamber alongside fuel and compressed air or oxygen, cooling the engine and increasing its power through the production and expansion of steam.


dry heater

(military, mechanical engineering) 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.


spur gear

Each axle has its own final drive two-step reduction, a bevel gear set and a spur gear set which drives the axle. Of these, the spur gears take most of the stress and the bevel gears provide optimum reduction at high speed and low torque—an arrangement which makes for easier assembly and reduced load for the bevel gears.

1962 June, “Beyond the Channel: U.S.S.R.: A 3,000 h.p. diesel-hydraulic from MaK”, in Modern Railways, page 416:

(mechanical engineering) The simplest type of gear wheel, with teeth projecting radially, parallel to its axis.


brake fade

To help prevent a runaway caused by brake fade, heavy trucks are required to stop at the top of the downgrade to give their brakes time to cool.

(automotive, rail transport, mechanical engineering) Partial or total loss of braking force with prolonged continuous or repetitive application of a heavy vehicle's brakes, due to the effects on the brake system of the heat generated by heavy braking.


reduction drive

reduction drive (plural reduction drives)

[...] there are also a direct drive to a hydraulic gear pump, and a reduction drive to two pumps in tandem; [...].

1962 December, “Talking of Trains: French track-layers for W.R.”, in Modern Railways, page 369:

(mechanical engineering) A device which reduces the input rotational speed to a lower output speed, and can also increase torque.


elliptic spring

elliptic spring (plural elliptic springs)

The bogie bolster itself is mounted on two double elliptic springs, which are spaced by a channel section spring plank suspended from the bogie frame by swing hangers and knife-edge rockers.

1962 December, “The B.R. standard diesel-electric Type 1 locomotive”, in Modern Railways, page 382:

(mechanical engineering, automotive) A curved leaf spring of different styles.


equalising beam

equalising beam (plural equalising beams)

equalising beams (plural)
equalizing beam (alternative)

Main suspension is by four triple nests of coil springs, which are mounted in spring cups on the forged steel underslung equalising beams. The equalising beam ends fit into stirrups cast integral with the Skefko self-aligning roller-bearing axleboxes. Woodhead-Monroe shock absorbers are fitted between the equalising beams and the bogie frame to damp the recoil of the primary suspension.

1962 December, “The B.R. standard diesel-electric Type ! locomotive”, in Modern Railways, page 382:

(British spelling, mechanical engineering) 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.


radius arm

The axles are guided within the bogie frames by radius arms and are fitted with disc brakes; magnetic rail brakes are also provided.

1963 May, “Europe's latest high-power locomotives”, in Modern Railways, page 298:


radial shaft seal

radial shaft seal (plural radial shaft seals)

(mechanical engineering) A seal for any rotary element.


lip seal

(mechanical engineering) A radial shaft seal.


T-beam

The T-beam is designed to economize in this respect by concentrating the concrete, where it is most effective, near the compressive side of the beam.

1915 April, Jerome Cochran, “Design Methods in Concrete Construction – Analysis of Stresses in T-Beams and Design of Beams in General”, in Concrete-Cement Age:

Similar to doubly reinforced sections, the T-beam detailed in Figure 3.7(6)(a) may be ‘decomposed’ into a web-beam and a flange-beam […]

2010, Yew-Chaye Loo, Sanaul Huq Chowdhury, “Ultimate strength analysis and design for bending”, in Reinforced and Prestressed Concrete:

(construction, mechanical engineering) A structural member with a cross section shaped like the letter T.


retaining valve

retaining valve (plural retaining valves)

(rail transport, mechanical engineering) A device that retains some air pressure in a train's air brake cylinders even when the automatic brake valve is set to the fully-released position, used on steep downgrades to allow a degree of continuous braking effort to be maintained without depleting the pressure in the train's brakepipe (which would result in the loss of nearly all braking ability, causing a runaway).


brakepipe

brakepipes (plural)
brake pipe (alternative)

(rail transport, mechanical engineering) A continuous pipe or hose filled with high-pressure air and running the length of a train, used to recharge the train's brake reservoirs with compressed air and to control the train's air brakes through changes in its internal air pressure.


cannon box

The outermost non-driven axle forms a pony truck within the bogie frame, with its bearings in a cannon box.

(mechanical engineering) A type of enclosure for axle bearings.


blucket

Blend of blade + bucket; the use of bucket here refers to the inner, turbine portion of the blade.

(aviation, mechanical engineering) A type of turbine blade where the inner portion of the blade is driven by expanding exhaust gases from the engine core, while the outer portion extends into the bypass duct and serves as a fan blade; used on a few turbofans with rear-mounted fans.


ship lift

ship lifts (plural)
shiplift (alternative)

(mechanical engineering) A device consisting of a structural platform which can be used to launch ships by lowering them into the water, or to lift them into dry dock.


bunker fuel

bunker fuel (usually uncountable, plural bunker fuels)

(mechanical engineering, petrochemistry, maritime) A type of extremely viscous, heavy fuel oil primarily used by large oceangoing ships.


bunker oil

bunker oil (usually uncountable, plural bunker oils)

bunker fuel
bunker fuel#English:_Q2611902

(mechanical engineering, petrochemistry, maritime) Synonym of bunker fuel.


stub axle

The axles of the Talgo section are U-shaped and the ends form stub-axles on which the wheels revolve freely and independently.

1962 September, P. Ransome-Wallis, “The Talgo trains of Spain”, in Modern Railways, page 177:

(automotive, mechanical engineering) An axle supporting only one wheel of a pair on opposite sides of a vehicle.


forced induction

(mechanical engineering, automotive, aviation) 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.


differential steering

(automotive, mechanical engineering) 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.


high-time

en-adj

high-time (comparative higher-time, superlative highest-time)

higher-time (comparative)
highest-time (superlative)

Boeing and the FAA conducted additional tests and research to further investigate why the rivets failed and what the possible repercussions of such a failure would be, including metallurgical examination of high-time bellcranks, material properties testing on old and new bellcranks, review of bellcrank failure rate data obtained from 767 operators, and examination of maintenance procedures to determine whether changes in procedures and/or intervals were warranted. The Safety Board monitored the FAA's and Boeing's tests and research into the bellcrank shear rivet failures.

2002 March 13, National Transportation Safety Board, “767 Bellcrank Anomalies”, in Aircraft Accident Brief: EgyptAir Flight 990, Boeing 767-366ER, SU-GAP, 60 Miles South of Nantucket, Massachusetts, October 31, 1999, archived from the original on 2022-05-11, page 18:

(mechanical engineering, especially aviation, of a vehicle or mechanical component) Having been in use for a (relatively) long time or a large number of operating cycles; nearing retirement or replacement age.


compressorless

(mechanical engineering) Not having compressors.


core lock

The lack of core rotation on the accident airplane engines was similar to the instances of core lock experienced by CF34 engines during Bombardier’s acceptance testing, except that the accident airplane engines were exposed to more severe thermal distress than the engines on the production airplanes. Specifically, the accident airplane’s engines flamed out from high power and high altitude, whereas the engines installed on the production airplanes were shut down only after their internal temperatures were stabilized.

2007 January 9, National Transportation Safety Board, “2.2.3 Double Engine Failure”, in Aircraft Accident Report: Crash of Pinnacle Airlines Flight 3701, Bombardier CL-600-2B19, N8396A, Jefferson City, Missouri, October 14, 2004, archived from the original on 2022-03-15, page 49:

(aviation, mechanical engineering) Seizure of a turbine engine due to misalignment and loss of clearance between stationary and rotating components, caused by different components cooling and contracting at different rates following engine shutdown or flameout.


core lock

en-verb

core lock (third-person singular simple present core locks, present participle core locking, simple past and past participle core locked)

core locks (present singular third-person)
core locking (participle present)
core locked (participle past)
core locked (past)

As testimony during the Safety Board’s June 2005 public hearing on the Pinnacle Airlines accident indicated, neither Bombardier nor GE considered core lock to be a safety-of-flight issue. The manufacturers claimed that engines that passed the screening procedure, with or without grind-in rework, would not core lock as long as the 240-knot airspeed was maintained.

2007 January 9, National Transportation Safety Board, “1.18.2 Core Lock”, in Aircraft Accident Report: Crash of Pinnacle Airlines Flight 3701, Bombardier CL-600-2B19, N8396A, Jefferson City, Missouri, October 14, 2004, archived from the original on 2022-03-15, page 37:

(aviation, mechanical engineering, of a turbine engine) To experience core lock.


core locked

Engines that are found to be core locked are reworked using an in-flight "grind-in" procedure that was designed to remove seal material at the interference location. Engines that undergo grind-in rework are then rescreened for core lock. The grind-in procedure is as follows [...]

(aviation, mechanical engineering) Affected by core lock.


journal box

(rail transport, mechanical engineering) A box or housing enclosing or supporting a journal, often used in order to retain the lubricant.


unport

unport (third-person singular simple present unports, present participle unporting, simple past and past participle unported)

unports (present singular third-person)
unporting (participle present)
unported (participle past)
unported (past)

(mechanical engineering, of a liquid such as fuel or oil, intransitive) To flow away from, and, thus, fail to enter, its intake or drain port.

Further, the apparent difficulties with the left engine could be explained by unporting of whatever fuel remained in the left tank. Conditions would have been conducive to unporting if, for example, the airplane was in a left bank and in a nose-right sideslip following the loss of the right engine, which is consistent with flying straight while attempting to turn to the left, as indicated by the pilot statement "we're trying" when the controller queried if the airplane was in a left turn. Assuming some usable fuel was in the left tank, it is probable that the flight crew's maneuvering after the right engine stoppage may have intermittently unported it, causing the sequential stoppage and restarting of the left engine. The Safety Board notes that the loss of the right engine occurred while the airplane was in relatively level flight and that the left engine stoppage occurred during attempts to maneuver back to the ILS course after the stoppage of the right engine. Further, the final loss of control may have been precipitated by momentary stopping or starting of the left engine when the airplane was at a reduced airspeed. Impact witness marks and airplane damage were consistent with a loss of control at low altitude.

2002 August 26, National Transportation Safety Board, Crash of Executive Airlines Jetstream 3101, Bear Creek Township, Pennsylvania, May 21, 2000, archived from the original on 2021-08-09, Engine Stoppage Scenarios, page 33:

(mechanical engineering, transitive) To cause (a liquid such as fuel or oil) to flow away from, and, thus, fail to enter, its intake or drain port.


unporting

(mechanical engineering) The action or process of unporting.


wheel lathe

It features inspection roads and pits, a wheel lathe, wash-plant, and storage and office space for training and support functions.

2022 December 14, “News in pictures: £70m Gosforth depot nears completion”, in RAIL, number 972, page 27:

(mechanical engineering, rail transport) A lathe for the manufacture and resurfacing of the wheels for rail vehicles.


chain-driven

No description of the Bulleid patent chain-driven valve-motion for locomotives has yet been made public, and until this happens we are unable to satisfy the interest of many readers in this unique locomotive equipment.

1946 November and December, “The Why and The Wherefore: Chain-Driven Valve-Motion”, in Railway Magazine, page 391:

(mechanical engineering) Referring to the transmission of power by means of a suitable endless chain, such as a bicycle chain.


slidebar

The slidebars are of the three-bar type with underhung crosshead.

1951 March, “British Railways Standard "Britannia" Class 4-6-2 Locomotives”, in Railway Magazine, page 186:

(mechanical engineering, UK) A crosshead guide.


crank axle

Except in the case of the largest 4-6-2, not yet in contemplation, use of two [outside] cylinders only was decided on for the following reasons:— […] 3. The crank axle is expensive in first cost and maintenance.

1951 July, “British Standard Locomotives”, in Railway Magazine, page 441:

internal-combustion engine
internal-combustion engine

(mechanical engineering, of steam locomotives) An axle formed in the manner of a crankshaft in an internal-combustion engine, having one or two cranked sections driven from one or two cylinders inside the main frames.


time history

en-noun

time history (countable and uncountable, plural time histories)

(engineering, mechanical engineering) A technique used in the field of structural dynamics to evaluate the behavior of structures under different loads and conditions, involving simulating the actual loads that a structure will experience over time.


free surface effect

free surface effect (plural free surface effects)

(physics, mechanical engineering) 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).


skew bevel gear

skew bevel gear (plural skew bevel gears)

(mechanical engineering) A bevel gear in which the teeth are slanted, forming a spiral-like shape.


bypass duct

(mechanical engineering) A component used in HVAC systems to manage airflow by providing an alternative path for excess air.


valve gear

valve gear (countable and uncountable, plural valve gears)

Three independent sets of Walschaerts valve gear are provided, those for the outside cylinders being driven by return cranks placed on the driving crankpins, and by crosshead arms attached to the crossheads.

1956 April, “"Merchant Navy" Class Pacific Modified”, in Railway Magazine, page 209:

(mechanical engineering) The mechanism of a steam engine that operates the inlet and exhaust valves to admit steam into the cylinder and allow exhaust steam to escape, respectively, at the correct points in the cycle.