Ipayipi elikhethekile le-petroleum lisetshenziselwa ikakhulukazi ukumba imithombo kawoyela negesi kanye nokudluliswa kukawoyela negesi. Kuhlanganisa ipayipi lokumba uwoyela, isikhwama sikawoyela kanye nepayipi lokumpompa uwoyela. Ipayipi lokubhoboza uwoyela lisetshenziselwa ukuxhuma ikhola yokubhoboza ku-drill bit kanye nokudlulisa amandla okubhola. I-oil casing isetshenziselwa ikakhulukazi ukusekela udonga lomthombo ngesikhathi sokumba nangemuva kokuqedwa, ukuze kuqinisekiswe inqubo yokubhoboza nokusebenza okuvamile kwawo wonke umthombo ngemva kokuqedwa. Ipayipi lokumpompa ngokuyinhloko lidlulisela amafutha negesi kusukela phansi komthombo kuya phezulu.

Isikhwama samafuthaiyindlela yokuphila yokusebenza komthombo kawoyela. Ngenxa yezimo ezihlukene zokwakheka komhlaba, isimo sengcindezi engaphansi komhlaba siyinkimbinkimbi, siyaqina, siyacindezela, siyagoba kanye nesenzo sokucindezeleka okuguquguqukayo emzimbeni wepayipi, okubeka phambili izidingo eziphakeme kwikhwalithi ye-casing ngokwayo. Uma i-casing ngokwayo ilimele ngesizathu esithile, wonke umthombo ungancishiswa ukukhiqizwa noma ushiywe.

Ngokusho kwamandla ensimbi ngokwayo, i-casing ingahlukaniswa ngamamaki ensimbi ahlukene, okungukuthiJ55, K55, N80, L80, C90, T95, P110, Q125, V150, njll. Izimo ezihlukene zomthombo, ukujula kahle, ukusetshenziswa kwebanga lensimbi nakho kuhlukile. I-casing ngokwayo nayo iyadingeka ukuze ibe nokumelana nokugqwala endaweni ebolayo. Esikhundleni sezimo ze-geological eziyinkimbinkimbi, i-casing nayo iyadingeka ukuze ibe namandla okumelana nokuwa.