Qhov tsis zoo ntawm cov txheej txheem ntawm aluminium alloy castings qhia tias cov hlau nyob hauv qab ntawm cov castings solidifies irregularly. Cov laj thawj yog raws li nram no:
1. Thaum cov hlau cam khwb cia hlau uas twb muaj lawm ua ntej ua ntej, cov kab nrib pleb, qhov sib sib zog nqus groove, nyias phab ntsa (txawm tias nyias dua li phab ntsa nruab nrab), cylindrical qhov phab ntsa thiab lwm qhov ntawm aluminium alloy casting yuav raug muab pov tseg.
2. Qhov kub ntawm cov pwm casting yog tsawg dhau;
3. Aluminium alloy casting kub yog tsawg dhau;
4. Lub rooj vag txoj hauj lwm ntawm cov pwm casting tsis zoo, thiab lub zog tsis kam yog loj.
Muaj roj nyob rau hauv pwm kab noj hniav, uas yog yus muaj los ntawm lub lubrication ntawm lub qis nto ntawm lub casting, tab sis cov duab yog tsis xwm yeem. Cov laj thawj yog raws li nram no:
1. Cov txheej txheem dhau los yog qhov nyuaj los kho. qhov twg cov roj sau;
2. Lub vuam hlau yog turbulent, thiab cov roj yog qhwv thaum nws ua haujlwm.
3. Tuag casting residual kab noj hniav.
4. Cov txheej txheej hauv zos ntawm cov pwm yog tshwm sim los ntawm cov txheej txheem tsis tsim nyog lossis cov txheej txheem txau tsis raug.
5. Qhov sib txawv ntawm qhov sib txawv los yog zawv zawg haum qhov sib txawv ntawm aluminium alloy tuag casting yog qhov loj heev, thiab cov hlau sib txuas thaum txhaws. Tom qab cov aluminium alloy yog cam khwb cia, aluminium alloy tsis yog tag nrho rub tawm, tab sis clamped nyob rau hauv qhov chaw.
Nco ntsoov tias thaum lub ncuav ib feem ntawm aluminium alloy casting yog qhov hnyav, nws tuaj yeem txiav txim siab tias cov duab ntawm aluminium alloy tuag casting tsis ua raws li qhov yuav tsum tau ua ntawm daim duab. Kev downcasting feem ntau tsis tso cai.