Ukubuka konke kwamapayipi e-petroleum asakhiwo amapayipi Amapayipi e-Petroleum Amapayipi I-ASME SA106, ASME SA179, ASME SA192, ASME SA210, ASME SA213, ASME SA335, njll Ibanga lamapayipi e-petroleum amapayipi asakhiwo I-API 5L PSL1, PSL2 I-API 5L I-API 5L Gr.B x42 x52 x60 x65 x70 njll I-API 5CT-2018 i-Casing and Tubing I-API 5CT I-API 5CT J55, K55, N80, N80Q, njll