API 5Lbụ ọkọlọtọ maka ọkpọkọ ahịrị ígwè eji ebu mmanụ, gas, na mmiri. Ọkọlọtọ ahụ na-ekpuchi ọtụtụ ọkwa nchara dị iche iche, nke X42 na X52 bụ akara ule abụọ. Isi ihe dị iche n'etiti X42 na X52 bụ ihe eji arụ ọrụ ha, ọkachasị na-enye ike na ike tensile.

X42: Opekempe mkpụrụ ike nke X42 ígwè ọkpọkọ bụ 42,000 psi (290 MPa), na ike ike ya sitere na 60,000-75,000 psi (415-520 MPa). A na-ejikarị ọkpọkọ ígwè X42 eme ihe na sistemu pipeline nwere nrụgide ọkara na ike chọrọ, dabara adaba maka ibufe mgbasa ozi dị ka mmanụ, gas, na mmiri.

X52: Opekempe mkpụrụ ike nke X52 ígwè ọkpọkọ bụ 52,000 psi (360 MPa), na tensile ike ranges si 66,000-95,000 psi (455-655 MPa). E jiri ya tụnyere X42, X52 ọkwa ígwè ọkpọkọ nwere ike dị elu ma dị mma maka usoro pipeline na nrụgide dị elu na ike chọrọ.

N'ihe gbasara ọkwa nnyefe,ọkọlọtọ API 5Lna-akọwapụta ọkwa nnyefe dị iche iche maka ọkpọkọ nchara enweghị nkebi na ọkpọkọ welded:

Igwe anaghị agba nchara (N steeti): N steeti na-ezo aka na ọnọdụ ọgwụgwọ na-eme ka ọ dị mma. Enweghị nkebi ígwè ọkpọkọ na- normalized tupu nnyefe ka homogenize na microstructure nke ígwè ọkpọkọ, si otú mma ya n'ibu Njirimara na siri ike. Normalizing nwere ike iwepụ nrụgide fọdụrụnụ ma melite nkwụsi ike akụkụ nke ọkpọkọ ígwè.

Ọkpụkpọ welded (M steeti): M steeti na-ezo aka na ọgwụgwọ thermomechanical nke ọkpọkọ welded mgbe emechara na ịgbado ọkụ. Site na ọgwụgwọ thermomechanical, a na-emezi microstructure nke ọkpọkọ welded, arụ ọrụ nke ebe ịgbado ọkụ na-eme ka ọ dịkwuo mma, na ike na ntụkwasị obi nke ọkpọkọ welded n'oge eji.

ọkọlọtọ API 5Lna-akọwapụta n'ụzọ zuru ezu ihe mejupụtara kemịkalụ, akụrụngwa akụrụngwa, ụzọ nrụpụta, nyocha na nyocha chọrọ nke ọkpọkọ ọkpọkọ pipeline. Mmezu nke ọkọlọtọ na-eme ka nchekwa na ntụkwasị obi nke ọkpọkọ ígwè pipeline mgbe ị na-ebu mmanụ, gas na mmiri ndị ọzọ. Nhọrọ nke akara ule kwesịrị ekwesị nke ọkpọ ígwè na ọkwa nnyefe nwere ike izute mkpa dị iche iche nke ọrụ injinia dị iche iche ma hụ na arụ ọrụ kwụsiri ike nke usoro pipeline.