Itọju iṣaju ti a bo pẹlu degreasing (degreasing), yiyọ ipata, phosphating awọn ẹya mẹta.Phosphating jẹ ọna asopọ aarin, idinku ati yiyọ ipata jẹ ilana igbaradi ṣaaju phosphating, nitorinaa ni iṣe iṣelọpọ, a ko yẹ ki o gba iṣẹ phosphating nikan bi idojukọ, ṣugbọn tun bẹrẹ lati awọn ibeere ti didara phosphating, ṣe iṣẹ ti o dara ni afikun si epo ati yiyọ ipata, ni pataki san ifojusi si ipa laarin wọn.