ʻO nā kumu a me nā mea e pale ai i ka ʻino ʻana o ka ʻili ʻana o nā lehelehe kila kila 304

Abstract: Ua kūʻai aku nei ka mea kūʻai aku i kahi pūʻulu o 304 stainless steel flanges, e ʻohi ʻia a hoʻololi ʻia ma mua o ka hoʻohana ʻana. ʻO ka hopena, ua ʻike ʻia nā ʻōhū ma ka ʻili o nā flanges kila kila ma hope o ka waiho ʻia ʻana i loko o ka pahu pickling no nā minuke he ʻumi. Ma hope o ka lawe ʻia ʻana o nā flanges a hoʻomaʻemaʻe ʻia, ʻike ʻia ka ʻino. I mea e ʻike ai i ke kumu o ka ʻino ʻana o nā flanges stainless steel, e pale i nā pilikia maikaʻi mai ke kū hou ʻana, a e hōʻemi i nā poho waiwai. Ua kono kūikawā mai ka mea kūʻai mai iā mākou e kōkua iā ia me ka nānā ʻana i ka sampling a me ka nānā metallographic.

ʻO ka mea mua, e ʻae mai iaʻu e hoʻolauna i ka 304 stainless steel flange. Loaʻa iā ia ke kūpaʻa corrosion maikaʻi, ka pale wela, a me nā waiwai mechanical haʻahaʻa. ʻAʻole kū i ka corrosion i ka lewa a me ka ʻakika. Hoʻohana nui ia i nā papahana pipeline wai e like me ka ʻaila a me ka ʻoihana kemika. Ma ke ʻano he ʻāpana koʻikoʻi o ka pilina pipeline, loaʻa iā ia nā pōmaikaʻi o ka hoʻopili maʻalahi a me ka hoʻohana ʻana, ka mālama ʻana i ka hana sealing pipeline, a me ka hoʻomaʻamaʻa i ka nānā ʻana a me ka hoʻololi ʻana i kekahi ʻāpana o ka pipeline.

Kaʻina nānā

1. E nānā i ka haku mele: ʻO ka mua, e hoʻāʻo i ka flange i ʻino ʻia a hoʻohana i ka spectrometer e hoʻoholo pololei i kona haku mele. Hōʻike ʻia nā hopena ma ke kiʻi ma lalo nei. Hoʻohālikelike ʻia me nā koi ʻenehana o 304 stainless steel chemical composition ma ASTMA276-2013,ʻoi aku ka haʻahaʻa o ka maʻiʻo Cr i loko o ka hui kemika o ka flange hemahema ma mua o ka waiwai maʻamau.

2. Nānā Metallographic: Ua ʻoki ʻia kahi laʻana keʻa lōʻihi ma ke kahua ʻino o ka flange hāʻule. Ma hope o ka poni ʻana, ʻaʻole i ʻike ʻia ka corrosion. Ua nānāʻia nā mea hoʻokomoʻole ma lalo o kahi microscope metallographic a ua heluʻia ka māhele sulfide e like me 1.5, ua heluʻia ka'āpana alumina e like me 0, ua heluʻia ka paʻakai paʻakai e like me 0, a ua heluʻia ka māhele spherical oxide i 1.5; ua kālai ʻia ka hāpana e ka waiʻawaʻawa ferric chloride hydrochloric acid a nānā ʻia ma lalo o kahi microscope metallographic 100x. Ua ʻike ʻia ʻaʻole like ʻole nā ​​​​palaoa austenite i loko o ka mea. Ua loiloi ʻia ka nui o ka palaoa e like me GB/T6394-2002. Hiki ke helu ʻia ka ʻāpana o ka palaoa ma ke ʻano he 1.5 a hiki ke helu ʻia ka ʻāpana palaoa maikaʻi e like me 4.0. Ma ka nānā ʻana i ka microstructure o ka corrosion kokoke i ka ʻili, hiki ke ʻike ʻia ka hoʻomaka ʻana o ka corrosion mai ka ʻili metala, hoʻopaʻa ʻia i nā palena o ka palaoa austenite a hoʻonui i loko o ka mea. Hoʻopau ʻia nā palena ʻai ma kēia wahi e ka ʻino, a ua aneane nalowale ka ikaika hoʻopaʻa ma waena o nā hua. ʻO ka metala i ʻinoʻino ʻia e hana i ka pauda, ​​a hiki ke ʻoki ʻia mai ka ʻili o ka mea.

3. ʻIke piha: Hōʻike nā hopena o nā hoʻokolohua kino a me nā kemika he haʻahaʻa haʻahaʻa ka ʻike Cr i loko o ka hui kemika o ka flange stainless steel ma mua o ka waiwai maʻamau. ʻO ka mea Cr ka mea nui loa e hoʻoholo ai i ke kūpaʻa ʻana o ke kila kila. Hiki iā ia ke hana me ka oxygen e hana i nā oxides Cr, e hana ana i kahi papa passivation e pale ai i ka corrosion; he kiʻekiʻe ka ʻike sulfide non-metallic i loko o ka mea, a ʻo ka hoʻohui ʻana o nā sulfides i nā wahi kūloko e alakaʻi i ka emi ʻana o ka Cr concentrate ma kahi a puni, e hana ana i kahi Cr-poor area, a laila e hoʻopilikia ai i ka pale ʻana o ke kila kila; ka nānā 'ana i ka palaoa o ka kuhiliʻole kila flange, e hiki ke ike i kona nui palaoa mea ole loa, a me ka uneven hui 'ana i loko o ka hui ua prone e hana i nāʻokoʻa i ka electrode hiki, ka hopena i ka micro-pāʻani, e alakai i ka electrochemical corrosion ma luna. ka ili o ka mea. ʻO nā ʻanoʻano koʻikoʻi a me ka maikaʻi i hui pū ʻia o ka flange stainless steel e pili nui ana i ke kaʻina hana deformation wela, ka mea i hana ʻia e ka deformation wikiwiki o nā kīʻaha i ka wā forging. ʻO ka nānā ʻana o ka microstructure o ka ʻino kokoke i ka ʻili o ka flange e hōʻike ana i ka hoʻomaka ʻana o ka ʻino mai ka ʻili o ka flange a hiki i loko ma ka palena o ka palaoa austenite. Hōʻike ka microstructure kiʻekiʻe kiʻekiʻe o ka mea i ʻoi aku ka nui o ke kolu o nā pae i hoʻoheheʻe ʻia ma ka palena o ka palaoa austenite o ka mea. ʻO ke kolu o nā ʻāpana i hōʻiliʻili ʻia ma ka palena o ka palaoa, hiki ke hoʻopau ʻia ka chromium ma ka palena o ka palaoa, e hōʻemi ana i ka ʻinoʻino intergranular a hōʻemi nui i kona kūpaʻa ʻana.

Ka hopena

Hiki ke kiʻi ʻia nā hopena aʻe mai nā kumu o ka pickling corrosion o 304 stainless steel flanges:

1. ʻO ka corrosion o nā flanges stainless steel ka hopena o ka hana i hui ʻia o nā kumu he nui, ma waena o ke kolu o ka pae i hoʻoheheʻe ʻia ma ka palena palaoa o ka mea ke kumu nui o ka hāʻule ʻana o ka flange. Manaʻo ʻia e hoʻopaʻa pono i ka mahana wela i ka wā hana wela, ʻaʻole e ʻoi aku ma mua o ka palena palena kiʻekiʻe o ke kaʻina hana hoʻomehana waiwai, a e hoʻomaha wikiwiki ma hope o ka hopena paʻa e pale aku ai i ka noho ʻana i ka pae wela o 450 ℃-925 ℃ no ka lōʻihi loa. e pale i ka ua o nā ʻāpana ʻekolu.
2. ʻO nā hua i hui pū ʻia i loko o nā mea e pili ana i ka ʻino electrochemical ma luna o ka ʻili o ka mea, a pono e hoʻomalu pono ʻia ka ratio forging i ka wā o ka hana forging.
3. ʻO ka haʻahaʻa haʻahaʻa Cr a me ka sulfide kiʻekiʻe i loko o ka mea pili pono i ka pale ʻana o ka flange. I ke koho ʻana i nā mea, pono e uku ʻia i ke koho ʻana i nā mea me ka maikaʻi metallurgical maʻemaʻe.