Quality centrifugal castings mumal tak neih theihna tur tips thenkhat
Air-cooled die tawi tak tak atang chuan .
Inhmelhriattirna:
Ni-resist groove insert siam nan chuan a tha ber chu carousel type centrifugal casting machine a ni a, a rei thei ang bera awm a ni a, RPM, temperature leh cycle time te automatic control a awm bawk. Volume lian tak tak siamtu hmingthang tak takte chuan a tlangpuiin 2-meter die an hmang thin. Die chu a tawp atanga a tawp thlenga temperature inang tlanga awm theih nan timed water-cooling hman a ni.
Captive casting siam emaw, low cost supplier-a sawn emaw-ah chuan, centrifugal casting machine hman tlangpuite chu tui-cooling tel lovin 300mm sei, 300mm a sei an nei a ni. Microstructure-a control chu a harsa zual a, a bik takin solidification chak zawk avangin pots hnunglam tawp lamah chuan a harsa zual hle. A hma lam chu a lum rei zawk a, he tawp lamah hian hot metal a rawn luang lut hnai zawk a ni.
Chutiang bêl aṭanga siam chhuah inserts-te microstructure quality sang tak leh a tawp thlenga siam chhuah chu quality sang tak leh a inmil theih nân, a siam chhuahnaah chuan thu bul awlsam ṭhenkhat chu ngun taka zawm a ngai a ni.
Melt buatsaih dan:
Input raw materials:
He material-a nickel percentage sang tak hian furnace, a capacity tling tawk, efficient taka melting leh mixing a mamawh a ni. Chumi atana tha ber chu mains frequency induction furnace a tlem berah 500-kg capacity leh a tha ber chu 1000-kg capacity a ni.
Input raw materials te chu a remchan dan anga thianghlim a ngai a ni. Carbide forming elements Mo, VA, Ti leh W te hi trace-ah dah tur a ni. FIMKHURNA: Sumdawnna atana hman tur pig iron tam takah chuan Mo leh Ti tam tak a awm a. A tawp berah chuan insert hnuhnung berah heng elements te hi a hnuaia tarlan ang hian control tur a ni:
Mo > 0.05% a ni.
Ti > 0.04% a ni.
W > 0.02% a ni.
VA > 0.02% a ni.
Steel scrap hi ni-resist material-a harsatna awm thei tur hriat lawk theih loh thlentu tramp elements a ni. Steel scrap hi a theih ang anga charge 10% max 10% leh a source leh composition hriat tawhah tihtlem tur a ni.
Chips leh borings te pawh a tlem thei ang bera dah tur a ni a, chu chu pumpelh theih loh vek a nih chuan .. Hengte hi 60% max-a tihtlem a duhthusam a, a vawt leh a thianghlim tur a ni.Chip uniform taka melt-a mix chu a harsa hle. Chip atanga element thenkhat hloh chu a sang hle a, chip-ah hian boruak leh hydrogen trapping a awm theihna a awm a, chungte chuan graphite tha lo leh coarse/clustered carbides a tichak a ni.
Sulphur chu melt-ah a awm a, range tawi takah chuan a ngai a ni. Hardness duhthusam hmuh theihna turin 0.06% velin dah tur a ni. Sulfur sang zawk hian microstructure ah harsatna a thlen thin.
Carbon tlukpui:
Carbon equivalent ( CE ) hi cast irons atana parameter pawimawh tak a nih thu hriat a ni. He factor hian casting-a microstructure lo awm chi hrang hrangah hian hmun pawimawh tak a chang a ni. A solidification rate nen hian a inzawm tlat a, chu chu a lehlamah chuan casting leh temperature cross-section te hian a nghawng a ni.
General Convention chu casting pakhata volume/surface (v/s) ratio anga CE value chhiar tur a ni. Cross-section hrang hrang nei 3-dimensional castings tan chuan hei hi a harsa hle. Centrifugal pots te hi 3-dimensional ni mahse, a sei zawng zawngah symmetrical section an ni a, chuvangin hengte tan hian V/S hi a hnuaia formula-a kan hmuh ang hian chhut theih a ni:
Volume / lei chung zau zawng ratio v/s .
V/S = ( D2 - d2 ) H / 4 (DH + DH + ( D 100) a ni.2 - d2 ) / 2 )
khawiah nge, d=pawn lam diameter ( od ) chu centrifugal cast pot .
D=Centrifugal cast pot chhunga a chhung lam diameter ( ID ) .
h=Centrifugal cast pot a san zawng .
Centrifugal cast pot atana thil tha zawk chu saturation℃a ni ang a, chu chu formula hmanga pek a ni:
Saturation℃nei . Sc :
;
khawiah nge, C, Si leh Ni te hi weight-% a value tak tak an ni.
Kan hmanna atan chuan s 1000 man duhthusam chu .c = 0,80 - 0,95
Furnace-a ce meter dah chuan pot-te i paih hmain metal chhunga carbon leh silicon awm zat chu khauh zawk leh rang zawka thunun theih a ni ang.
Inoculation hnua C, SI & MN range rawt a ni:
Carbon: 2.70 – 2.80% a ni.
Silicon: 2.10 – 2.20% a ni.
Manganese: 1.20 – 1.30% a ni.
Melting: 1.1.
Ni-resist material-a nickel leh copper tam tak inzawmkhawmna tur chuan charge loading chu furnace-ah stratify a pawimawh hle. Input material charging sequence duhthusam chu 50% pig iron + scrap thlak hmasak a ni a, a hmin mai chuan nickel, copper, ferro alloys, carbon te dah la, a tawpah chuan balance 50% pig iron nen top up rawh.
Carbon hi a bul tannaah bath-ah 2.75 - 2.80%-ah a awm tur a ni a, Ni chu 14.5 -15%-ah, silicon 1.8 – 1.9%-ah, chromium chu 1.15 –1.2%-ah, 1.2 – 1.25%-ah chromium-ah dah tur a ni.
Silicon carbide hnathawh dan:
Melt-a nucleation site tling tak neih theihna turin SIC hian hmun pawimawh tak a chang a ni. Chuvangin SIC chuan original charge make-up calculation-ah a then a siam tur a ni. Tin, SIC additions dang pawh super-heating the melt hma lawk hian a ngai a, chu chu chemistry check leh approve a nih veleh; Tin, ladles tlemte hnuah pawh tap out a nih hnuah, chutiang chuan carbon depletion chu compensated a ni. Hei hian carbon awm zat tur limit hnai tak a siam theih nan a pui ang a, chuvang chuan CE leh microstructure pawh a inmil zawk ang.
Charge make-up-a SIC awm zat rawt chu charge zawng zawng atanga 0.25% a ni a, chu chu charge-a alloying elements dah belh te nen a ni. He addition hi carbon leh silicon te charge make-up ah chhut a ni. Melt chu 1400C temperature a thlen hnuah chemistry chu check a ni a, a tul chuan siamthat hna thawh a ni a, enfiah leh a ni. Chemistry chu pawm a nih hnuah, 0.1% SIC dang dah belh a ni a, furnace chu full setting-ah dah nghal a ni a, melt chu hnathawh temperature-ah super-heated a ni a (a tlangpuiin 1480 –1500 C a ni a, chu chu ladle tin atanga die-a pouring-in a luh zawh huna a tlahniam beisei a nih dan azirin), a chhuahna tur ladle tan a ni.
SIC dah belh pawh hi pouring cycle chhungin carbon hloh zat tihpun nan regular interval-ah tih tur a ni. Melting set-up leh operating condition pek tawh pakhat tana SIC additions quantity leh timing mamawh dik tak tehna atan chuan hun kal zelah carbon drop atan uluk taka enkawl heat engemaw zat kalpui a tha ber. Continuing production mode-ah chuan ladle tap tina carbon awm zat enfiah chuan carbon chu eng stage-ah nge furnace-ah calculated quantity a dah a, gain a tap chhuah hmain minute engemaw zat ei phalsak a ngai tih hriat theihna tur data tling a pe ang.
Ladle filling leh inoculation:
Ladle eng pawh production area-a dah a nih hma chuan lining chu a vawt vek tur a ni a, torch flame hman nen a lum thei ang bera tihlum tur a ni. Shift tan tirh leh chawlh hnuah furnace atanga molten metal nen relalling hmanga tih tur hnuhnung ber a ni. Ladle chu metal hman tur tap hmain 750C a mamawh tlem berah 750C-a hruai luh theih nan reladling pakhat aia tam a ngai thei. Contact pyrometer hmangin temperature a dik em tih enfiah tur a ni.
Theory-ah chuan NI material sang tak tak te hi mahni invanoculating an ni. Mahse kan section of centrifugal castings leh microstructure-a rigid controls te tan chuan, a theih ang anga ladle-a inoculation siam chu duhthusam leh mamawh a ni. High grade ferro silicon ( 75 % ) hmanga inoculation atana operating range chu 0.20 atanga 0.25 % Si pick- up rawn luh theihna tura chhut a ni. Strontium-in a tihbuai avangin he material-a superseed ang chi cast iron inoculants hmanlai hman loh a tha.
Rare earths rawn luh tir hian kan microstructure a pui ang. Inoculant reseed tha zawk, cerium hmanga hman theih dan tur chu zirchian theih a ni.
Tin, inoculant nena an rawn luh nickel-mag controlled quantity hian chilled graphite pumpelh nan nghawng tha tak a nei thei bawk.
Dies: 100 a ni.
Ruangam siam:
Controlled water-cooling hi a tawp atanga a tawp thlenga die temperature inang tlanga awm theihna turin a tha hle. Mahse, tui cooling rawn luh a harsat chuan a hma lamah inlet awmna jacket remchang hnuaiah die chu air cooling tih theih a ni.
Machinability problem hi a tam zawk chu rear end inserts-ah chauh a awm avangin rear end inserts-a microstructures te zirchian a, microstructure inserts tha tak tak chauh production-a a luh theihna tura cut-off mamawh tlem ber tur hriat a tha. Naturally air-cooled short dies 300mm length tan chuan a tlangpuiin 40-mm tal cut-off a ngai a ni.
Hun rei tak chhung chu rear end plug thar siamin pot sei zawng chu 30 – 35mm in tihpun tur a ni. Hei hian pot tin atanga insert cut zat tihchhiat lohvin cut-off lian zawk pawh a siam thei dawn a ni.
A optimum solution chu heng dies te hi re-designing ah a awm a, 600 mm a sei pot lak a ni a, chutah chuan productive chu a hnung lamah 50mm cut-off pawhin a pung a ni.
Insulation: 1.1.
Thih tawi tam tak chuan dry insulting materials chu ID-ah an hmang a, chu chu insulation leh separator angin an thawk a ni. Wet insulation materials tha zawk a awm a, chu chuan chilling laka invenna tha zawk a pe ang.
Tin, a hma lam leh a theih chuan dies hnung lam flanges te pawh insulate a duhthusam a ni.
Die ID surface chu a siam chhuah theih hun chhung engtik lai pawhin 300C hnuaiah a awm tur a ni lo. Chutiang a nih theih nan chuan die tinah contact pyrometer hman theih a ni tur a ni.
Shift tin tan tirh leh break apiangin id-a die temperature chu 300C aia sang a nih theih nan a tul angin dummy pot 1 emaw a aia tam emaw theh tur a ni.
Production a kal zel chuan die temperature chu a sang chho zel ang a, 450 – 500 C ah a stabilize ang a, hei hi short, naturally cooled dies te tan chuan temperature tha ber a ni.
Records:
Parameter zawng zawng enkawl chhunzawm zel a, record dik leh dik tak vawn reng a pawimawh hle.
Development stages-ah pawh ladle tinte carbon leh silicon records enkawl leh chuta tang chuan SIC addition program siam chu a finthlak hle bawk.
Microstructure control chu a theih ang anga tih fo tur a ni a, a hnuhnung bera insert cut thar ber chu pot hnunglam tawp atanga cut-naah tih fo tur a ni a, chu chu casting leh cut-off atana parameters te chu a fully stabilized thlengin tih tur a ni.
