Centrifugal casting-a thil awm dan leh chhiatna awmte .
Centrifugal casting bimetal composite pipe defects leh control centrifugal casting hmanga control, gravity casting grain structure aiin a tha zawk daih thei, rangkachak pahnih a hmu thei a, metallurgical composite-a tel a ni thei a, metal junction layer hnih chu inner component transition smooth, crossing area-ah a awm thei a, chu chu a tha thei ang bera siam theih a ni a, hei hian alter hrang hrang a awm a, chu chu a danglamna chu a ni. Heat stress stratification a ni. Centrifugal casting-a schematic diagram chu Figure 5-ah hian kan hmu a.
1.1 Pipe blank-a centrifugal casting hnuah, a tehna hmanrua chu: Intercept 12 Sections at both end of the 6 pipe blanks, cross section tin diameter chu vertical direction-ah vawi hnih teh tur a ni a, section tinte ellipticity chu chhut tur a ni. Figure 6-ah hian plot analysis atana section 12 te ellipticity a awm a. Section 12 zingah hian ellipticity maximum 12mm a tling tih hmuh theih a ni a, ellipticity error pakhat zel chu a lian hle a, chuvangin, lining thickness chu a inang lo hle a ni.1.2 Billet base-a cracking defects Centrifugal casting zawhah chuan radial crack chu billet base base level-ah a awm tlangpui a ni. Base level-a base level atanga base level atanga crack te chu base leh lining layer inkar transition area tawp thlengin an inzar pharh a, lining layer ah chuan crack a awm lo thung.
3 Centrifugal Casting Defect Defect Control 3.1 Centrifugal Casting Defect Control Centrifugal Casting speed hniam lutuk hian metal liquid rain phenomenon a rawn lang ang a, pipe pawh a ti tlem ang a, a loose, slag, pipe billet inner surface uneven defects Speed a sang lutuk a, tube hi a chhe thei a, segregation leh defect dang a awm duh a, double metal lining layer thickness inang lo tak tak te pawh hi speed sang tak avanga lo awm a nih avangin pipe thickness venna leh pipe base crack defect te hi control speed lam a ni ber. Tube billet thickness inang lo leh tube billet base crack defect hi rotation speed vang a ni a, thil dang erawh chuan nghawng a nei tlem hle thung. Centrifugal casting hmanga formula tawnhriat nei te:
n 299 G R
chutah chuan r chu casting chhunglam radius a ni a, CM; G chu gravity coefficient a ni a; n chu centrifugal speed a ni a, r / min. Cast steel-a gravity coefficient chu 40~76 a ni a, bimetal composite pipe chhung lam diameter chu 146mm a ni a, centrifugal casting speed chhiar dan chu 699 ~ 964 r/min a ni. Chuvangin, centrifugal casting speed chu a siam dan tak tak angin siamthat a ni. Test zawhah chuan speed chu 950 leh 1050 r / min inkar a control a ni a, pipe thickness inang lo awm theihna chu nasa takin a tlahniam a, crack defects chu a bul berah chuan a bo vek a ni.
Centrifugal casting hian static casting nen hian defect tam tak a nei a, mahse centrifugal casting-ah chuan defect siam duhna a tlem zawk. Casting production-a chhiatna thleng tlangpui chu stoma (pinhole), crack (tear), lap, shrinkage hole, etc., leh ribbon bedding leh ruah sur lohna te hi centrifugal casting-ah chuan a danglam bik a ni. Centrifugal casting-a thick-wall steel pipe siam hi a harsa ber a, a chhan chu thick-wall steel pipe hi hot crack, irregular segregation, lap leh defect dang siam awlsam a ni a, thin-wall steel pipe emaw cast iron pipe emaw chu lap leh crack defect siam awlsam a ni. Centrifugal casting-ah chuan copper alloy solidification mode chu paste solidification a ni a, chuvangin copper alloy centrifugal casting hian a tlangpuiin crack leh tears ang chi defect a siam lo tlangpui a, casting siam chhuah pawh hian defect a nei lo tluk a ni.2 Centrifugal casting-a defects Main defects 2.1 Layered Defects Centrifugal casting defects te pawh hi becabetrif-ah chauh hriat a ni a, becabesting are banded becathed are banded are band becathed, Casting, generally casting wall thickness chu 80mm aia tam a ni a, thin-wall casting erawh a lang tlem hle thung. Ribbon lamination defects chu melting point compound hniam (common crystal phase leh oxide emaw sulfide clamp, debris, ribbon, edge contrast strong contrast line pawn lama awm, centrifugal casting-a a tam zawk chu ribbon bedding defects-in a nghawng ang a, alloy solidification range zau zawk, he thil thleng hian a ti tlem zawk a, chu chu a tlahniam thei a, chu chu a ti tlem a, hei hi a ni a, chu chu a ni a, chu chu a ti tlem a, chu chu a ti tlem thei a, chu chu a fallifus a ni thei a, chu chu a ti thei a ni. A nih loh leh, a rotation speed leh a temperature leh model te chu ribbon ang chi bedding defects chungchangah hian a awm thei a, chu chu cast-a cast dang, a rotation-a a rotation-a a segregation a inthlak danglam vang a ni. Metal chu a vibration vang a ni lo va, metal liquid chu cast-a a luh chuan, tubular cast solidification chu kawng engemaw takin a lo awm chuan, liquid metal dang chuan special position a thlen tlai lutuk chuan, original liquid metal chuan a zawng zawng emaw, a then emaw a thlen tawh chuan, he thil thleng hian, a lap, a vawt emaw, a layered emaw, intermittent strip bedding defects tia koh a ni ang, cast cast too cast-a cast too cast-ah a awm ang. Rast, ruah phenomenon a thleng dawn a, ruah sur chu molten metal anga sawi theih a ni a, cast chung atanga a hnuai lam thlenga ruah sur angin a tla a, Figure 1-a shshown hi ruahsa phenomenon schematic diagram a ni a, he phenomenon hi molten metal fluid chu rotating cast-a a sir lehlamah a rawn luang chhuak a, chu chu molten metal liquid-in a accelerate lo a nih chuan a rotating cast-ah a lo chhuak lo a, chu chu a low a ni. Molten metal wall, molten metal chuan gravity hneh thei tur khawpa rotational speed a thleng dawn lo, rain shower phenomenon dang a awm thei a, chu chu molten metal liquid chu casting temperature-a a sang lutuk a nih chuan, viscosity chu a tlahniam a, chu chu molten speed a ni a, chu chu a harsa hle ang, a nih chuan, a chak tawk ang a, chu chu a ni thei ang. casting to remedy A dang chu casting coating a ni a, a casting a, a casting a rotation speed a sang thei a ni.
2.3 Shrink hole leh cold separation Molten metal liquid chu cast-ah rang taka dah luh a nih chuan cast chhungah overheat a siam ang. Cast pawn lama solidification nen khaikhin chuan cast core solidification hi a slow a, metal temperature sang zawk hian shrink hole siamna tur condition a pe bawk. Molten metal liquid chu zawi zawiin a hnuai lamah an theh chuan, metal liquid chu cast wall-ah grain-ah a lo thang lian a, chu chuan directional solidification chu section pumpuiah a kal zel a, a core bula shrinkage hole chu a tlem berah a thleng ang. Cold separation hi LAP an ti bawk a, chu chu pouring process dik lo hman a nih vang a ni a, chu chu unstable pouring, injection speed te a ni a, chuvangin pouring speed hian a fully ensure a, metal liquid chu casting surface pum puiah a lut chhunzawm zel a, chutah chuan casting tawp a thleng thei a ni. Pouring speed a slow lutuk chuan flow off phenomenon a siam ang a, cold separation phenomenon pawh a rawn lang ang.
2.4 Centrifugal casting-ah hian degregation leh crack-ah chuan section thick casting chu segregation a awm awlsam hle. Casting-ah chuan centrifuge a inher avangin, eng position-ah pawh metal liquid chuan composition casting pawn lam segregation a siam ang. Centrifugal castings thatna pakhat chu compact tissue tam zawk an hmuh theih vang a ni a, mahse casting chu a lum lutuk a, a lum lutuk a nih chuan bawlhhlawh leh gas chu casting-ah a tla ang. Alloy liquid hian phosphorus leh sulfur content a nei sang tawk a nih chuan he phenomenon hi a langsar zawk ang. inthliarna thlentu ber: unbalanced centrifuge system-a vibration thunun theih loh; Ruahsur phenomenon chu molten metal fluid a ni a, a inher chhuak slow vang a ni; a luang tam lutuk chuan; leh slow solidification speed.Crack defects hian centrifugal casting atan form bik a siam lo va, static casting atan pawh centrifugal casting atan pawh fimkhurna ang chiah hi hman theih a ni.
2.5 Needle Orifice Stoma (stoma, eye) Centrifugal casting-ah pawh stomatal defects a awm ve deuh a, liquid metal liquid-ah gas tam tak a awm a, taksa emaw cast-ah emaw tui a awm a, a nih loh leh paint thlan chu a remchang lo a, needle orifice emaw mitdelna emaw a awm ang. Casting-ah chuan, metal casting hian gas tlanchhuahna tur pores a neih loh avangin, leh metal liquid centrifugal casting pawh a rang hle a, chuvangin pinhole chu thin-walled casting-ah a lo chhuak a ni. Pinhole stoma defects hi a hnuaia mi ang hian tih loh theih a ni: cast iron cast aiah steel cast hmang la, type; Casting hmaa preheating; crystalline water awmna coating material hmang suh; Pouring temperature sang lutuk hmang suh. Paint hman hunah chuan bentonite chu tui nen uluk taka inhmeh a nih loh chuan crystalline tui chu dry bentonite-ah a awm thei a, a lumna metal liquid lumna chuan crystalline tui chu a tithianghlim ang a, stomatal defects chu a siam awlsam ang. Cast coating chu thawk theih a nih chuan, a lo awm gas chu molten metal liquid leh cast wall inkarah a darh a, chu chu gas chu a tel lo ang a, chu chu stomatal defects tihbo nan a tha hle ang. Bronze leh iron casting-ah chuan pinhole ang chi pores chu cast pawnah chuan hmun thianghlim leh eng ang maiin, cast chhunga hemp pit ang maiin a lang a, pores diameter pawh a tlem hle. Metal liquid melting-ah pawh, gas dissolution a thlen thei bawk ang, dissolved gas has hydrogen, oxygen and nitrogen, etc., raw materials preheating leh drying hmangin, gas infiltration a tihtlem tha thei a, boiling melting method hmangin gas a paih thei bawk.
2.6 Internal loosening leh central slag defects Casting tissue density enfiah tur chuan casting hian pawn lam atanga chhung lam thlengin sequential solidification a nei tur a ni. Chutiang chuan layer tin solidification leh contraction-ah chuan liquid metal liquid chhung lam layer-in compensation a mamawh a ni. Metal chu rang taka leih a nih chuan a chhung lam ah cooling nasa tak a awm a, casting chhungah hian loosening a awm a, chu chu chhung lam leh pawn lam atanga solidification lo awm avanga lo awm a ni. Sand casting atan chuan pawn lam atanga cooling speed a hniam hle a, a chhung lam atanga leh pawn lam atanga a lumna a lum a, chuvangin solidification front chung lamah a tlahniam a, heng defects te hi pumpelh turin, a chhung lam boruak lumna chu directional solidification control theih tur khawpa sang taka dah tur a ni a, chu chu a chhunga drying chu a inang lo a nih chuan, molten metal liquid chuan pouring, a pouring, a produce thei a ni.
