This HTML5 document contains 87 embedded RDF statements represented using HTML+Microdata notation.

The embedded RDF content will be recognized by any processor of HTML5 Microdata.

Namespace Prefixes

PrefixIRI
dbpedia-dehttp://de.dbpedia.org/resource/
dctermshttp://purl.org/dc/terms/
yago-reshttp://yago-knowledge.org/resource/
dbohttp://dbpedia.org/ontology/
n20http://dbpedia.org/resource/File:
foafhttp://xmlns.com/foaf/0.1/
n11https://global.dbpedia.org/id/
yagohttp://dbpedia.org/class/yago/
rdfshttp://www.w3.org/2000/01/rdf-schema#
freebasehttp://rdf.freebase.com/ns/
dbpedia-pthttp://pt.dbpedia.org/resource/
n15http://commons.wikimedia.org/wiki/Special:FilePath/
rdfhttp://www.w3.org/1999/02/22-rdf-syntax-ns#
owlhttp://www.w3.org/2002/07/owl#
dbpedia-vihttp://vi.dbpedia.org/resource/
wikipedia-enhttp://en.wikipedia.org/wiki/
provhttp://www.w3.org/ns/prov#
dbchttp://dbpedia.org/resource/Category:
n19https://web.archive.org/web/20041224170755/http:/umweltbundesamt.de/umweltvertraegliche-stoffe-e/
xsdhhttp://www.w3.org/2001/XMLSchema#
wikidatahttp://www.wikidata.org/entity/
goldhttp://purl.org/linguistics/gold/
dbrhttp://dbpedia.org/resource/

Statements

Subject Item
dbr:Extreme_pressure_additive
rdf:type
yago:Object100002684 yago:Component103081021 yago:WikicatLubricants yago:PhysicalEntity100001930 yago:Matter100020827 yago:WikicatOilAdditives yago:Substance100020090 yago:Part103892891 yago:Additive102679788 yago:Addition102679415 yago:Lubricant114890659
rdfs:label
Extreme pressure additive Aditivo para extrema pressão EP-Additiv
rdfs:comment
Extreme pressure additives, or EP additives, are additives for lubricants with a role to decrease wear of the parts of the gears exposed to very high pressures. They are also added to cutting fluids for machining of metals. Extreme pressure additives are usually used in applications such as gearboxes, while antiwear additives are used with lighter load applications such as hydraulic and automotive engines. Some of the EP additives are: Polysulfides serve as carriers of inactive and active sulfur. EP-Additive (Extreme-Pressure-Additive) werden Schmierstoffen zugesetzt und verbessern deren tribologische Eigenschaften, d. h., sie verhindern das Verschweißen von zwei aneinander reibenden metallischen Werkstoffen. Aditivos para extrema pressão, citados na literatura inglesa como EP additives (de extreme pressure additives), são aditivos para lubrificantes cujo papel é diminuir o desgaste das peças de engrenagens e outros componentes de máquinas expostas a pressões muito elevadas. Eles são adicionados também a fluidos de corte de metais em usinagem.
foaf:depiction
n15:CH2_dtc_2.svg
dcterms:subject
dbc:Oil_additives
dbo:wikiPageID
3155791
dbo:wikiPageRevisionID
1107091037
dbo:wikiPageWikiLink
dbr:Boron dbr:Fatty_acid dbr:Soap dbr:Petroleum dbr:Molybdenum dbr:Bioaccumulation dbr:Pressure dbr:Machining dbr:Metal dbr:Brass dbr:Dithiocarbamate dbr:Ester dbr:Tricresyl_phosphate dbr:Thiol dbr:Transmission_(mechanics) dbr:Temperature dbr:Carbon dbr:Cutting_fluid dbr:Sulfur dbr:Lubricant dbr:Motor_oil dbr:Antiwear_additives dbr:Zinc_dithiophosphate dbr:Engine dbr:Lead dbr:Haloalkane dbr:Molybdenum_disulfide dbr:Organophosphate dbr:Chlorendic_acid n20:CH2_dtc_2.svg dbc:Oil_additives dbr:Polysulfide dbr:Corrosion dbr:Phosphorus dbr:Bronze dbr:Chemical_reaction dbr:Gasoline_additive dbr:Copper_alloy dbr:Gear_oil dbr:Chlorinated_hydrocarbon dbr:Phosphoric_acid dbr:Oil_additive dbr:Alkane dbr:Gear dbr:Zinc dbr:Zinc_dialkyldithiophosphate dbr:Metalworking dbr:Chlorinated_paraffins dbr:Chlorine dbr:Stainless_steel
dbo:wikiPageExternalLink
n19:pressure.htm
owl:sameAs
freebase:m.08w06t dbpedia-de:EP-Additiv n11:JaBA yago-res:Extreme_pressure_additive wikidata:Q1275603 dbpedia-pt:Aditivo_para_extrema_pressão dbpedia-vi:Phụ_gia_áp_suất_cực_cao
dbo:thumbnail
n15:CH2_dtc_2.svg?width=300
dbo:abstract
Aditivos para extrema pressão, citados na literatura inglesa como EP additives (de extreme pressure additives), são aditivos para lubrificantes cujo papel é diminuir o desgaste das peças de engrenagens e outros componentes de máquinas expostas a pressões muito elevadas. Eles são adicionados também a fluidos de corte de metais em usinagem. Extreme pressure additives, or EP additives, are additives for lubricants with a role to decrease wear of the parts of the gears exposed to very high pressures. They are also added to cutting fluids for machining of metals. Extreme pressure additives are usually used in applications such as gearboxes, while antiwear additives are used with lighter load applications such as hydraulic and automotive engines. Extreme pressure gear oils perform well over a range of temperatures, speeds and gear sizes to help prevent damage to the gears during starting and stopping of the engine. Unlike antiwear additives, extreme pressure additives are rarely used in motor oils. The sulfur or chlorine compounds contained in them can react with water and combustion byproducts, forming acids that facilitate corrosion of the engine parts and bearings. Extreme pressure additives typically contain organic sulfur, phosphorus or chlorine compounds, including sulfur-phosphorus and sulfur-phosphorus-boron compounds, which chemically react with the metal surface under high pressure conditions. Under such conditions, small irregularities on the sliding surfaces cause localized flashes of high temperature (300-1000 °C), without significant increase of the average surface temperature. The chemical reaction between the additives and the surface is confined to this area. The early extreme pressure additives were based on lead salts of fatty acids ("lead soaps"), "active sulfur" compounds (e.g. thiols and elementary sulfur), and chlorinated compounds. During the 1950s the use of lead soaps was eliminated and replaced by zinc and phosphorus compounds such as zinc dithiophosphate. Some of the EP additives are: * Dark inactive sulfurized fat * Dark active sulfurized fat * Dark active sulfur hydrocarbon * Short and medium chain chlorinated alkanes (see chlorinated hydrocarbons and chlorinated paraffins) * Esters of chlorendic acid * Polymer esters * Polysulfides * Molybdenum compounds Aliphatic chlorinated hydrocarbons (chlorinated paraffins) are cheap and efficient, however they persist in environment and have strong tendency for bioaccumulation. Therefore, they are being replaced with alternatives. In cutting fluids, their role is largely confined to formulations for forming complex stainless steel parts. [1] The activity of halogenated hydrocarbons increases with decreasing stability of the carbon-halogen bond. At local contact temperatures ranging between 305-330 °C, the additive thermally decomposes and the reactive halogen atoms form a surface layer of iron halides on the part surface. Eventual failure of the contact point comes when the contact temperature exceeds the melting point of the iron halide layer. Under such conditions, small particles of carbon are generated as well. Some compounds used in lubricant additives are chloroalkanes, trichloromethyl phosphine acids, organic esters of a-acetoxy-b,b,b-trichloroethyl phosphonic acid, trichloromethyl esters of phosphoric acid, trichloromethyl derivates of sulfur, trichloroacetoxy compounds, esters or amine salts of chlorendic acid, 1,2,3,4,7,7-hexachloro-5-dimethylbicyclo[2.2.1]-2-heptene, etc. Oil-soluble organophosphates, with or without zinc, have excellent high-pressure and antiwear properties, and provide corrosion protection especially in presence of chlorinated hydrocarbons. Zinc dialkyldithiophosphates (ZDDP) start decomposing at 130-170 °C, while the activation temperature of tricresyl phosphate (TCP) typically exceeds 200 °C. Their reaction products form a chemically bonded lubricating film on the surfaces. Polysulfides serve as carriers of inactive and active sulfur. Molybdenum compounds decompose under high pressure to form an in-situ deposited layer of molybdenum disulfide. Molybdenum dithiocarbamates are used as additives for greases. Sulfur containing extreme pressure additives can cause corrosion problems in gears with parts made of bronze, brass and other copper alloy when high temperature environments are encountered. EP-Additive (Extreme-Pressure-Additive) werden Schmierstoffen zugesetzt und verbessern deren tribologische Eigenschaften, d. h., sie verhindern das Verschweißen von zwei aneinander reibenden metallischen Werkstoffen.
gold:hypernym
dbr:Additives
prov:wasDerivedFrom
wikipedia-en:Extreme_pressure_additive?oldid=1107091037&ns=0
dbo:wikiPageLength
5526
foaf:isPrimaryTopicOf
wikipedia-en:Extreme_pressure_additive