Chimiro uye Nheyo yeKushanda:
Muchina wekuyedza mwero wekuyerera kwemvura inonyungudika imhando yemuchina wepurasitiki unoyedzwa. Pasi pemamiriro ekupisa akatarwa, sampuro inofanira kuyedzwa inopiswa kusvika yanyungudika nechoto chinodziya zvakanyanya. Sampuro yakanyungudika inozoburitswa neburi diki rine dhayamita yakatarwa pasi pemutoro wehuremu hwakatarwa. Mukugadzirwa kwepurasitiki kwemabhizinesi emaindasitiri uye kutsvagurudza kwemasangano ekutsvagurudza kwesainzi, "mwero wekuyerera kwekunyungudika (huremu)" unowanzo shandiswa kumiririra kuyerera, viscosity uye zvimwe zvinhu zve polymer zviri mumamiriro akanyungudika. Iyo inonzi melt index inoreva avhareji yehuremu hwechikamu chega chega chemuenzaniso wakanyungudika unoshandurwa kuita huwandu hwekubuda mumaminitsi gumi.
Chishandiso chekuyerera kwemvura inonyungudika (hukuru) chinoratidzwa neMFR, iyo unit iri: magiramu pamaminitsi gumi (g/min).
Fomura yacho ndeiyi:
MFR(θ, mnom) = tref . m / t
Kupi: θ —- tembiricha yekuedza
Mnom— - mutoro wezita (Kg)
m —- avhareji yehuremu hwechikamu chakatemwa, g
tref —- nguva yekutarisa (maminetsi gumi), S (masekondi mazana matanhatu)
t ——- nguva yekupera, s
Muenzaniso:
Boka remasampuli epurasitiki rakachekwa masekondi makumi matatu ega ega, uye mhedzisiro yehuremu hwechikamu chimwe nechimwe yaive: 0.0816 magiramu, 0.0862 magiramu, 0.0815 magiramu, 0.0895 magiramu, 0.0825 magiramu.
Avhareji kukosha m = (0.0816 + 0.0862 + 0.0815 + 0.0895 + 0.0825) ÷ 5 = 0.0843 (magiramu)
Tsiva fomura iyi: MFR = 600 × 0.0843 / 30 = 1.686 (magiramu pamaminitsi gumi)