Njira yochiritsira ya thovu ya polyurethane imakhala ndi magawo angapo: kukulitsa koyambirira, kuyanika pamwamba, kuchiritsa mkati, ndi kuumitsa kwathunthu.
Choyamba, kukulitsa kumayamba mkati mwa masekondi 5-15 a kupopera mbewu mankhwalawa, kuchulukirachulukira kuchuluka kwake. Gawoli limakhudzidwa kwambiri ndi chinyezi chozungulira; Kuchuluka kwa chinyezi kumabweretsa kuchitapo kanthu mwachangu.
Chotsatira ndi siteji yowumitsa pamwamba, yomwe imakhala pafupifupi mphindi 10 (pa kutentha kwa madigiri 20 ndi chinyezi cha 50%). Panthawiyi, filimu yopyapyala imapanga pamwamba pa chithovu, zomwe zimapangitsa kuti zisakhalenso zomata, koma mkati mwake zimakhala zofewa. Ino ndi nthawi yoyenera kusintha mawonekedwe.
Gawo lochizira lamkati limafuna nthawi yayitali. M'chilimwe (kutentha kwa 25-30 digiri), kuchiritsa kwathunthu kumatenga pafupifupi maola 4-6; m'nyengo yozizira (kutentha kwa 0-10 digiri), imatha kupitilira maola 24 kapena kupitilira apo. Nthawi ya gel osakaniza, kuyambira kupopera mbewu mankhwalawa mpaka kutaya kwa fluidity, nthawi zambiri ndi mphindi 5-10, kutengera chothandizira ndi kutentha.
Zomwe zimakhudza nthawi yochiritsa ndi kutentha, chinyezi, ndi makulidwe a thovu. Pakuwonjezeka kwa kutentha kwa madigiri 10 aliwonse, zomwe zimachitika zimachulukanso. Chinyezi chochepa chimachedwa kuchira; Choncho, kupopera madzi kumathandiza kumalo owuma. Pamene makulidwe a colloid apitilira 5cm, kutentha kwamkati kumatha kufulumizitsa kuchiritsa komanso kumawonjezera chiopsezo cha voids.
M'madera akum'mwera kwachinyontho, nthawi yochiritsa imakhala yaifupi, zomwe zimathandizira kugwiritsa ntchito. M'madera owuma, ozizira kumpoto, njira zotetezera ndizofunikira. Muzogwiritsira ntchito, tikulimbikitsidwa kuti tidikire maola 24 musanayambe ntchito, monga kudula kapena kujambula, kuti mutsimikizire mphamvu.
Pansi pamikhalidwe yapadera, monga kugwiritsa ntchito pansi pamadzi, nthawi yochiritsa ikhoza kufupikitsidwa chifukwa madzi amatenga nawo mbali pakuchitapo kanthu. Komabe, ziyenera kukumbukiridwa kuti kuchiritsa kofulumira kwambiri kungakhudze kufanana.
Kumvetsetsa njirazi kungathandize ogwiritsa ntchito kukonza bwino ntchito ndikupewa zolakwika za pulogalamu.