Very bad flat spot

A Flat spot, or Wheel flat, is a fault in railroad wheel shape. A flat spot occurs when a rail vehicle's wheelset is dragged along the rail after the wheel/axle has stopped rotating. Flat spots are usually caused by faulty brakes or wheelset bearings. It can also be caused by use of the emergency brake, or slip and slide conditions that causes wheels to lock up while the train is still moving.

Consequences[link]

If the flat spot is very small, the rail vehicle will be able to continue being used. The fault is removed later in the wheelset turning process, using a wheel lathe. However, because of the heat suffered while being dragged along the rail and the impacts suffered afterward, these wheels are more likely to break due to changes in the alloy structure.

If the flat spot is very large (as in the picture), strands of molten metal may have got stuck on one side of the flat spot, making it impossible for the wheel to turn due to insufficient clearance between the rolling surface and the brake block. In this case, the wheelset must be replaced immediately.

In extreme cases, a wheel with an untreated flat spot can damage the track and cause a derailment.

Automobile use[link]

In automobile parlance, a flat spot occurs when the driver presses the accelerator pedal and there is a delay in the engine's response. This fault was more common before cars had electronic fuel injection.

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Look up flat in Wiktionary, the free dictionary.

Flat, or flatness, describes an object or condition that is very smooth or level.

Flat or flats may also refer to:

Places[link]

• Flat, a residential house or apartment
• Flat, Alaska, United States
• Flat, Missouri, United States
• Flat, Puy-de-Dôme, a commune in région Auvergne, France
• Flat, Texas, United States
• Flat Brook, tributary of the Delaware River in Sussex County, New Jersey
• Flat Island, Hong Kong, People's Republic of China
• Flat River (North Carolina), a river in Southern Person County, North Carolina
• Flats, West Virginia, an unincorporated community in Hardy County, West Virginia, USA

Arts[link]

• Flat (music), a symbol (♭) which denotes a lower pitch
• Flats (comics), the first stage in the comic coloring process
• Flats (theatre), flat pieces of theatrical scenery
• Flats (band), English band
• Flat!, a 2010 Indian film

Footwear[link]

• Flats, footwear which is not high-heeled
• Racing flats, lightweight shoes used primarily for running a race
• Ballet slippers are often referred to as 'flats' or 'flat shoes', as opposed to the Pointe shoes more advanced female dancers wear

Mathematics and geometry[link]

• Flat (geometry), the generalization of lines and planes in an n-dimensional Euclidean space
• Flat (matroids), a further generalization of flats from linear algebra to the context of matroids
• For use of flat sign in mathematics, see musical isomorphism - mapping vectors to covectors
• Flat morphism in algebraic geometry
• Flat module in abstract algebra

Transportation[link]

• Flat, a deflated pneumatic tire
• Flat car, an open container on wheels designed to carry heavy loads
• Flat spot, a fault in the shape of a railroad wheel

Other uses[link]

• Flat, a two-dimensional toy soldier made of tin or plastic
• Flat, a leading type of wordplay predating the invention of crosswords, as identified by the National Puzzlers' League
• Flats or flat butterflies, certain skipper butterfly genera in subfamily Pyrginae:
  • Celaenorrhinus of tribe Celaenorrhini;
  • Calleagris (scarce flats),
  • Eagris, and
  • Tagiades (water flats, snow flats) of tribe Tagiadini
• Flats (USPS), an oversized letter
• Optical flat, an extremely flat piece of glass
• Forest Lake Area Trail System

See also[link]

• All pages beginning with "Flat"
• All pages with titles containing "Flat"
• The Flat (disambiguation page)
• The Flats
• Flatten (disambiguation)
• Flattening
• Mudflat
• Planar (disambiguation)

This disambiguation page lists articles associated with the same title. If an internal link led you here, you may wish to change the link to point directly to the intended article.

Look up spot in Wiktionary, the free dictionary.

The common noun or verb spot has many meanings in English.

Otherwise, Spot or SPOT may refer to:

Advertising[link]

• Radio spot
• TV spot
• Underwriting spot

Fiction[link]

• Spot the Dog, a series of children's books adapted for animation
• Spot (chicken), a character in 101 Dalmatians: The Series
• Spot (comics), a Spider-Man villain
• Spot (Star Trek), a pet cat in Star Trek: The Next Generation
• A character in the cartoon series Hong Kong Phooey
• A pet dragon in the TV series The Munsters
• A pet dog in the Dick and Jane textbook series
• Dairine's sentient computer in the Young Wizards series.
• A deity in a sketch by Canadian comedy troupe The Kids In The Hall, who is initially assumed to be a harmless mistyping of "dog".

Localities[link]

• The Spot, New South Wales, a locality in Sydney, Australia

Music[link]

• Spot (album), by the synthpop band And One
• Spot (music festival), a music festival held in Denmark
• SPOT (producer), the house producer and engineer for the label SST Records
• Spot (rapper/producer)
• Singing Priests of Tagbilaran, a Filipino musical group
• Jerry Chamberlain, the guitarist for the rock group the Swirling Eddies
• An acronym for "Sex Pistols On Tour Secretly", the name the Sex Pistols toured under in the United Kingdom.

Biology[link]

• Spot croaker, a fish (Leiostomus xanthurus)
• SpoT (Biology), a bacterial protein that hydrolizes (p)ppGpp
• Spot (disease), several typically spot-forming fungal or bacterial leaf diseases on plants, caused for example by Diplocarpon variants (Black Spot on roses)
• Pimple, a skin blemish
• Campbell de Morgan spots, small red spots on the skin (usually harmless)
• Metrorrhagia, vaginal bleeding that is not synchronized with a menstrual period.

Other meanings[link]

• Cool Spot, a mascot for 7 Up soft drinks
• Spot (professional wrestling), a pre-planned wrestling move or series of moves
• SPOT (satellites), Satellite Pour l'Observation de la Terre, Earth-observing satellite family
• SPOT Satellite Messenger
• Spot date, a financial term
• Spot Fetcher, a dog owned by U.S. President George W. Bush
• Spot price, a financial term for price of trade done today
• Smart Personal Objects Technology, a Microsoft initiative
• Scott Draves, (known as 'Spot'), digital artist and VJ
• A nickname for a spotlight
• Old Australian and New Zealand slang for one hundred dollars
• "Screening passengers by observation techniques" (SPOT), an airport security technique
• Spots (cannabis) are a method of smoking cannabis. In the United States this is often called hotknifing.
• Single Point of Truth, a principle aimed at reducing duplication in software engineering.
• USS Spot, an American submarine that served during World War II.
• Spot market is a financial market, in which financial instruments or commodities are traded for immediate delivery ("on the spot").

See also[link]

• All pages beginning with "Spot"
• Spotz (disambiguation)

This disambiguation page lists articles associated with the same title. If an internal link led you here, you may wish to change the link to point directly to the intended article.