API 5Lʻo ia ka maʻamau no ka paipu laina kila i hoʻohana ʻia no ka lawe ʻana i ka aila, ke kinoea maoli, a me ka wai. Hoʻopili ka maʻamau i nā māka like ʻole o ke kila, ʻo X42 a me X52 ʻelua mau māka maʻamau. ʻO ka ʻokoʻa nui ma waena o X42 a me X52 ʻo ​​kā lākou mau waiwai mechanical, ʻoi aku ka ikaika a me ka ikaika tensile.

X42: ʻO ka ikaika haʻahaʻa haʻahaʻa o ka paipu kila X42 he 42,000 psi (290 MPa), a ʻo kona ikaika tensile mai 60,000-75,000 psi (415-520 MPa). Hoʻohana maʻamau ʻia ka paipu kila X42 i nā ʻōnaehana pipeline me ke kaomi maʻamau a me nā koi ikaika, kūpono no ka lawe ʻana i nā media e like me ka aila, ke kinoea maoli, a me ka wai.

X52: ʻO ka ikaika liʻiliʻi loa o ka paipu kila X52 he 52,000 psi (360 MPa), a ʻo ka ikaika tensile mai 66,000-95,000 psi (455-655 MPa). Ke hoʻohālikelike ʻia me X42, ʻoi aku ka ikaika o ka paipu kila X52 a kūpono i nā ʻōnaehana pipeline me nā koi kiʻekiʻe a me nā koi ikaika.

Ma ke kūlana o ka lawe ʻana,API 5L maʻamaukuhikuhi i nā kūlana hoʻouna like ʻole no nā paipu kila ʻole a me nā paipu welded:

ʻO ka paipu kila ʻole (N mokuʻāina): N ka mokuʻāina e pili ana i ke kūlana mālama maʻamau. Hoʻomaʻamaʻa ʻia nā paipu kila seamless ma mua o ka hoʻouna ʻana e homogenize i ka microstructure o ka paipu kila, a laila e hoʻomaikaʻi ai i kona ʻano mechanical a me ka paʻakikī. Hiki i ka Normalizing ke hoʻopau i ke koena o ke kaumaha a hoʻomaikaʻi i ke kūpaʻa dimensional o ka paipu kila.

ʻO ka paipu welded (M state): ʻO ka mokuʻāina M e pili ana i ka mālama thermomechanical o ka paipu welded ma hope o ka hana ʻana a me ka wili. Ma o ka mālama ʻana i ka thermomechanical, hoʻomaikaʻi ʻia ka microstructure o ka paipu welded, hoʻomaikaʻi ʻia ka hana o ka wahi wili, a hōʻoia ʻia ka ikaika a me ka hilinaʻi o ka paipu welded i ka wā hoʻohana.

API 5L maʻamauwehewehe kikoʻī i ka haku mele, nā waiwai mechanical, nā ʻano hana, ka nānā ʻana a me nā koi hoʻāʻo o nā paipu kila pipeline. ʻO ka hoʻokōʻana i ka maʻamau e hōʻoia i ka palekana a me ka hilinaʻi o nā paipu kila pipeline i ka laweʻana i kaʻaila, ke kinoea maoli a me nā wai'ē aʻe. ʻO ke koho ʻana i nā māka kūpono o nā paipu kila a me ke kūlana hoʻopuka hiki ke hoʻokō i nā pono kikoʻī o nā papahana ʻenekinia like ʻole a hōʻoia i ka hana paʻa o ka ʻōnaehana pipeline.