Vuam arc yog Nqe lus piav qhia thiab yam ntxwv

2024 Tus sau: Howard Calhoun | [email protected]. Kawg hloov kho: 2023-12-17 10:28

Yuav kom ua tiav cov txheej txheem vuam, yuav tsum muaj vuam arc. Qhov no yog ib qho hluav taws xob tawm, uas yog tus cwj pwm los ntawm lub zog siab heev thiab ntev heev. Nws tshwm sim ntawm cov khoom xws li electrodes uas nyob hauv ib puag ncig gaseous. Yuav kom muaj qhov arc tshwm sim, qhov hluav taws xob yuav tsum tau siv rau cov electrodes.

piav qhia dav dav ntawm arc

Lub ntsiab sib txawv ntawm cov vuam arc yog qhov kub thiab txias, nrog rau qhov ceev tam sim no. Ua tsaug rau ob qhov zoo, hauv kev sib xyaw ua ke, lub arc muaj peev xwm yaj cov hlau nrog lub melting point ntawm 3000 degrees Celsius yam tsis muaj teeb meem. Peb tuaj yeem hais tias qhov arc no yog tus neeg xyuas pib, uas muaj cov khoom tsis haum, thiab lub hom phiaj tseem ceeb yog hloov hluav taws xob hluav taws xob mus rau lub zog thermal. Tus nqi hluav taws xob nws tus kheej yog lub sijhawm hluav taws xob tam sim no dhau los ntawm qhov nruab nrab gaseous.

Nyob zoo ib tsoom niam txiv kwv tij neej tsas sawv daws

Lub vuam arc yog qhov tso tawm, thiab vim muaj ntau hom ntawm nws, kuj muaj ntau homarches:

1. thawj ntau yam hu ua glow discharge. Qhov zoo li no tsuas yog tshwm sim nyob rau hauv ib puag ncig uas tsis tshua muaj siab, thiab tsuas yog siv rau hauv cov khoom xws li cov ntxaij lim dej lossis cov teeb fluorescent xwb.
2. hom thib ob yog lub txim taws tawm. Qhov tshwm sim ntawm hom no tshwm sim nyob rau lub sijhawm thaum lub siab yog kwv yees li sib npaug ntawm atmospheric. Nws txawv nyob rau hauv hais tias nws muaj ib tug es intermittent zoo li. Ib qho piv txwv zoo ntawm qhov tso tawm yog xob laim.
3. vuam arc yog ib qho arc tawm. Nws yog hom no uas feem ntau siv thaum vuam. Nws tshwm sim nyob rau hauv lub xub ntiag ntawm atmospheric siab, thiab nws cov duab yog nruam.
4. hom kawg hu ua crown. Feem ntau tshwm sim yog tias lub electrode nto yog ntxhib thiab tsis sib xws.

Ntxim ntawm arc

Nws tsim nyog hais tias qhov hluav taws xob vuam arc tsis yog qhov nyuaj li nws zoo li thaum xub thawj siab ib muag, nws yooj yim heev kom nkag siab txog nws qhov xwm txheej. Nws siv cov hluav taws xob tam sim no uas ntws los ntawm cov khoom xws li cathode. Tom qab ntawd, nws nkag mus rau ib puag ncig nrog cov roj ionized. Lub sijhawm no, qhov tso tawm tshwm sim, uas yog lub teeb ci ntsa iab thiab kub heev. Feem ntau, vuam arc tuaj yeem muaj qhov kub ntawm 7,000 txog 10,000 degrees Celsius. Tom qab dhau los ntawm theem no, tam sim no yuav dhau mus rau cov khoom uas tau welded. Peb tuaj yeem hais tias qhov chaw ntawm qhov vuam arc yog qhov hluav taws xob tam sim no tau hloov pauv.

Vim qhov kub no, lub arc yuav tawm infraredthiab ultraviolet rays, uas yog teeb meem rau tib neeg noj qab haus huv. Nws yog qhov txaus ntshai rau tib neeg lub qhov muag, thiab tseem tuaj yeem tso lub teeb hlawv. Rau cov laj thawj saum toj no, txhua tus welders yuav tsum muaj cov cuab yeej tiv thaiv tus kheej zoo.

Arc structure

Cov qauv (cov qauv) ntawm cov vuam arc suav nrog peb lub ntsiab lus, lossis ntu - ntu anode thiab cathode, nrog rau cov kab arc. Nws yuav tsum tau muab sau tseg tias thaum lub sij hawm hlawv ntawm vuam arc, active me ntsis los yog cov cheeb tsam yuav tsim nyob rau hauv cov cheeb tsam ntawm lub anode thiab cathode, uas yog yus muaj los ntawm qhov kub siab tshaj tus nqi. Los ntawm ob qhov chaw no yuav dhau tag nrho cov hluav taws xob tam sim no uas cov khoom siv hluav taws xob tsim tawm. Nyob rau tib lub sij hawm, qhov loj tshaj plaws voltage poob ntawm vuam arc kuj yuav raug kaw nyob rau hauv ob qhov chaw. Cov kab arc nyob nruab nrab ntawm ob cheeb tsam no, thiab xws li qhov ntsuas qhov ntsuas hluav taws xob poob, qhov no, yuav tsawg heev.

Los ntawm cov lus hais dhau los, peb tuaj yeem xaus tias, ua ntej, lub zog ntawm cov vuam arc tuaj yeem tsim hluav taws xob ncaj ncees thiab siab tam sim no. Qhov thib ob, qhov ntev ntawm lub arc yuav suav nrog tag nrho ntawm cov cheeb tsam uas tau teev tseg saum toj no. Feem ntau, qhov ntev ntawm xws li ib tug arc yog ob peb millimeters, muab hais tias lub anode thiab cathode cheeb tsam yog feem 10-4 thiab 10-5 cm. Qhov zoo tshaj plaws ntev yog ib tug arc ntawm 4-6 hli. Nws yog nrog cov cim qhia tias nws yuav ua tau kom ua tiav kev sib txuas ruaj khov thiab kub siab.

Type of arc

Qhov sib txawv ntawm qhov vuam arc nyob rau hauv txoj kev mus kom ze, nrog rau hauv ib puag ncig uas nws tuaj yeem tshwm sim. Tam sim no, muaj ob hom arc feem ntau:

• Arc of direct action. Nyob rau hauv cov ntaub ntawv no, lub vuam tshuab yuav tsum ua tib yam rau cov khoom yuav tsum tau welded. Ib qho hluav taws xob arc yuav tshwm sim thaum lub kaum sab xis ntawm cov hlau ua haujlwm thiab cov electrode yog 90 degrees.
• Qhov thib ob tseem ceeb ntau yam yog ib qho kev ncaj qha ntawm vuam arc. Nws tshwm sim tsuas yog yog siv ob lub electrodes, thiab lawv nyob ntawm lub kaum sab xis ntawm 40-60 degrees nrog rau qhov chaw ntawm cov hlau. Ib qho arc yuav tsim ntawm ob lub ntsiab lus thiab txuas cov hlau ua ke.

Kev faib tawm

Nws tsim nyog sau cia tias muaj kev faib tawm ntawm lub arc nyob ntawm qhov chaw uas nws yuav tshwm sim. Txog niaj hnub no, peb hom tau paub:

• thawj hom yog qhib arc. Thaum vuam hom no, lub arc yuav hlawv nyob rau hauv qhov qhib cua, thiab ib tug me me roj txheej yuav tsim nyob ib ncig ntawm nws, uas yuav muaj xws li vapors ntawm hlau, electrodes thiab lawv coatings.
• hom kaw. Qhov kub ntawm xws li vuam arc yog tus yam ntxwv ntawm qhov tseeb tias nws yog nqa tawm nyob rau hauv ib txheej ntawm flux.
• Qhov kawg ntau yam yog arc nrog cov khoom siv roj. Hauv qhov no, cov khoom siv xws li helium, argon lossis carbon dioxide tau muab rau nws. Qee lwm hom roj kuj tseem siv tau.

Qhov txawv ntawm hom kawg yog qhov ntawdCov pa roj nkag yuav tiv thaiv qhov tshwm sim ntawm cov hlau oxidation thaum vuam.

Ib qhov sib txawv me ntsis kuj tau pom nyob rau hauv cov nqe lus ntawm lub sij hawm ntawm xws li arc. Raws li nws cov yam ntxwv, qhov vuam arc tuaj yeem nyob ruaj ruaj lossis pulsed. Nyob ruaj ruaj yog siv rau kev nruam vuam ntawm cov hlau, uas yog, nws yog nruam. Pulse arc hom yog ib qho cuam tshuam rau cov hlau, chiseled kov.

Cov khoom ua haujlwm, uas yog, electrodes, tuaj yeem yog carbon lossis tungsten. Cov electrodes no tseem hu ua non-consumable. Cov ntsiab lus hlau kuj tuaj yeem siv tau, tab sis lawv yuav yaj zoo ib yam li cov khoom ua haujlwm. Hom electrode feem ntau yog hlau thaum nws los txog rau hom melting. Txawm li cas los xij, kev siv cov hom tsis melting yog nrov dua niaj hnub no.

Lub sijhawm ntawm qhov tshwm sim

Qhov vuam arc tshwm sim thaum lub sijhawm muaj kev kub ceev tshwm sim. Qhov no tshwm sim thaum lub electrode los rau hauv kev sib cuag nrog ib tug hlau workpiece. Vim lub fact tias qhov kub tsuas yog loj, cov hlau pib yaj, thiab ib tug nyias strip ntawm molten hlau tshwm ntawm lub electrode thiab lub workpiece. Thaum cov electrode thiab cov hlau sib txawv, qhov tom kawg evaporates yuav luag tam sim ntawd, txij li tam sim no qhov ntom ntom heev. Tom ntej no, cov roj yog ionized, uas yog vim li cas qhov vuam arc tshwm.

Arc condition

Raws li tus qauv txheej txheem, uas yog, ntawm qhov nruab nrab kub ntawm 25 degrees thiab siab ntawm 1huab cua, cov pa roj tsis muaj peev xwm ua hluav taws xob. Lub ntsiab yuav tsum tau rau qhov tshwm sim ntawm arc yog ionization ntawm gaseous nruab nrab ntawm cov electrodes. Hauv lwm lo lus, cov roj yuav tsum muaj qee cov khoom siv hluav taws xob, hluav taws xob lossis ions.

Qhov thib ob tseem ceeb uas yuav tsum tau ua yog kev saib xyuas tas li ntawm qhov kub thiab txias ntawm cathode. Qhov kub xav tau yuav nyob ntawm cov yam ntxwv xws li qhov xwm txheej ntawm cathode thiab nws txoj kab uas hla thiab qhov loj me. Qhov kub thiab txias yuav ua lub luag haujlwm tseem ceeb. Lub vuam arc yuav tsum ruaj khov thiab tib lub sijhawm muaj lub zog loj tam sim no, uas yuav muab qhov ntsuas kub siab (7 txhiab degrees Celsius lossis ntau dua). Yog tias tag nrho cov xwm txheej tau ua tiav, ces txhua yam khoom siv tuaj yeem ua tiav nrog cov txiaj ntsig arc. Txhawm rau kom ntseeg tau tias muaj qhov kub thiab txias tsis tu ncua, nws yog ib qho tsim nyog kom lub hwj huam mov ua haujlwm ruaj khov li sai tau. Nws yog vim li no tias lub zog hluav taws xob yog qhov tseem ceeb tshaj plaws thaum xaiv lub tshuab vuam.

Arc nta

Muaj ntau yam uas paub qhov txawv ntawm qhov vuam arc los ntawm lwm yam hluav taws xob tawm.

Thawj yog qhov loj tam sim no ceev, uas tuaj yeem ncav cuag ntau txhiab amperes ib square centimeter. Qhov no muab qhov kub thiab txias thaum lub sijhawm ua haujlwm. Kev faib tawm ntawm cov hluav taws xob hluav taws xob nruab nrab ntawm cov electrodes hauv lawv qhov chaw yog qhov tsis sib xws. Nyob ze cov ntsiab lus no, pom muaj zog voltage poob, thiab ntawm qhov chaw, ntawm qhov tsis sib xws, nws txo qis heev. Nws yog tsis yooj yim sua tsis hais txog qhov dependence ntawm qhov kub thiab txias ntawm qhov ntev ntawm kab. Qhov ntev ntev, qhov cua kub tsis zoo,thiab vice versa. Siv vuam arcs, koj tuaj yeem tau txais qhov sib txawv tam sim no-voltage yam ntxwv (CVC).

Vuam inverter. Lub arc thiab nws cov nta

Nws tsim nyog pib tam sim ntawd nrog qhov sib txawv tseem ceeb ntawm lub zog inverter thiab cov pa, transformer ib qho. Kev siv hluav taws xob hluav taws xob tau raug txo los ntawm yuav luag ib nrab. Cov yam ntxwv ntawm cov tam sim no uas tshwm sim thaum siv lub inverter tso cai rau kom ceev ignition ntawm lub arc, thiab kuj ua kom ruaj khov nyob rau hauv tag nrho cov txheej txheem.

Los ntawm nws tus kheej, lub vuam inverter yog ib qho cuab yeej nyuaj uas ua haujlwm los hloov qhov tam sim no kom ntseeg tau tias kev ua haujlwm ruaj khov tshaj plaws ntawm lub arc. Piv txwv li, cov cuab yeej txuas nrog lub network thiab tau txais kev hloov pauv tam sim no raws li cov tswv yim, uas nws tuaj yeem hloov mus rau tam sim no ncaj qha. Tom ntej no, cov tam sim no ncaj qha nkag mus rau hauv inverter thaiv, qhov twg nws rov hloov dua siab tshiab rau alternating tam sim no, tab sis nyob rau ntawm ib tug ntau zaus dua li nws nyob rau hauv lub network. Qhov tam sim no yog pauv mus rau lub transformer, qhov twg nws voltage yog ho txo, uas tsub kom nws lub zog. Tom qab ntawd, lub rectified thiab tuned alternating tam sim no raug xa mus rau lub rectifier, qhov twg nws yog hloov dua siab tshiab rau tam sim no thiab muab rau kev khiav hauj lwm.