Incoloy Alloy Parts: 825 vs 800 don Sabis na Lalata 

Lokacin da injiniya ya ƙayyade wani incoloy part don layi mai lalacewa, zaɓi tsakanin Alloy 825 da Alloy 800 yana da wuya game da abin da gami ke "mafi kyau." Yana da game da wanne gami ya dace da ainihin yanayin sabis. An tsara Incoloy 825 (UNS N08825) don rage acid, kafofin watsa labarai masu ɗaukar chloride, da mahalli mai tsami. An tsara Incoloy 800 (UNS N08800) don ƙarfin zafin jiki mai ƙarfi da juriya na iskar shaka, tare da aikin lalata a cikin kafofin watsa labarai na ruwa azaman fa'ida ta biyu. Rikita waɗannan biyun na iya haifar da ko dai farashin da ba dole ba ko kuma abin da bai dace da buƙatun sabis ba.

An rubuta wannan kwatancen don injiniyoyi, na waje, da injiniyoyi masu musayar zafi da masu siye waɗanda ke buƙatar tsarin zaɓi mai amfani, ba cikakken littafin jagorar kayan ba. Yana mai da hankali kan dabaru na ƙarfe da ke bayan kowane gami, ɓangaren yana samar da inda zaɓin ya fi dacewa, da ƙirƙira da wuraren siye waɗanda ke tantance ko ƙayyadadden gami yana yin sabis.

Incoloy 825 vs 800: Bambancin Matsayi

Hanya mafi sauƙi don tsara bambance-bambancen ita ce: Alloy 825 shine lalata-na farko; Alloy 800 shine zafi-na farko.

Alloy 825 na dangin Ni-Fe-Cr-Mo-Cu ne. Abubuwan da ke cikin nickel suna zaune a cikin kewayon 38-46%, tare da ƙari da gangan na molybdenum (2.5-3.5%) da jan ƙarfe (1.5-3.0%), tare da daidaitawar titanium. An ƙirƙiri wannan haɗin don ɗaukar duka oxidizing da rage acid, tsayayya da lalata damuwa na chloride, da jure yanayin sabis mai tsami mai ɗauke da H₂S.

Alloy 800 shine Ni-Fe-Cr gami da kusan 30-35% nickel da 19-23% chromium, amma babu molybdenum na ganganci kuma babu ƙari na jan karfe. Ƙirar ƙira ita ce sabis na zafin jiki mai girma: juriya na iskar shaka, juriya na carburization, da ƙarfin rarrafe a yanayin zafi har zuwa kusan 593 ° C don tushe 800 na tushe, tare da 800H da 800HT suna haɓaka wannan kewayon gaba. A cikin kafofin watsa labarai masu lalata ruwa ba tare da chloride mai tsanani ba ko rage bayyanar acid, 800 yana yin aiki yadda ya kamata, amma juriyar lalatarsa ta fi kunkuntar ta ƙira.

Don an incoloy part a cikin layin tsarin sinadarai mai sarrafa sulfuric acid tare da chlorides, 825 shine ƙayyadaddun da suka dace. Don goyan bayan tanderu ko zoben haɗin zafi mai zafi, 800 galibi shine mafi dacewa da zaɓin tattalin arziki. Shawarar ya kamata ta bi tsarin lalatar da ya fi girma, ba wai sunan gamammen alloy ba.

Haɗin Kan Haɗin Kai da Lalata Juriya

Abin da Nickel, Chromium, Molybdenum, da Copper suke yi

Juriya na lalata na Alloy 825 ba tasiri guda ɗaya bane. Kowane ƙari na alloy yana magance takamaiman yanayin gazawa.

Nickel yana ba da tushe don juriya ga lalata damuwa na chloride (SCC). Matsakaicin 38-46% nickel a cikin 825 ya isa ya tsayayya da chloride-ion SCC a wurare da yawa. Ƙananan abun ciki na nickel na Alloy 800 (30-35%) kuma yana ba da juriya na SCC mai amfani a yawancin kafofin watsa labaru na ruwa, amma mafi girma nickel a cikin 825 yana ba da fa'ida mafi girma a cikin sabis na chloride mai tsanani.

Chromium yana samar da fim ɗin m oxide wanda ke ba da kariya daga watsa shirye-shirye kamar nitric acid da oxidizing salts. Dukansu 800 da 825 sun dogara da chromium don wannan aikin, kuma duka sun ƙunshi kusan 19-23.5% Cr.

Molybdenum shine inda allunan biyu suka bambanta sosai. 2.5-3.5% Mo a cikin 825 yana haɓaka juriya ga ramuka da lalata, musamman a cikin mahalli masu ɗauke da chloride. Alloy 800 ya ƙunshi babu ƙarin molybdenum na ganganci. Wannan rashi ba aibi ba ne a cikin ƙirar 800; kawai yana nuna cewa 800 ba a ƙirƙira shi don juriya na chloride ba.

Copper, wanda yake a 1.5-3.0% a cikin 825, yana aiki tare da molybdenum don tsayayya da rage acid, musamman sulfuric da phosphoric acid. Alloy 800 ya ƙunshi babu ƙarin jan ƙarfe. A cikin sabis na sulfuric acid mai narkewa, abun ciki na jan karfe 825 shine babban dalilin da aka ayyana inda 800 ba zai kasance ba.

Titanium a cikin 825 yana aiki azaman stabilizer, ɗaure carbon don hana hazo chromium carbide yayin walda da rage haɗarin haɓakawa. Wannan shine dalilin da ya sa aka kwatanta 825 a matsayin mai juriya ga lalatawar intergranular a cikin yanayin as-welded.

Abin da Rashin Mo da Cu na 800 ke nufi a cikin Ayyuka

Bai kamata a yi watsi da Alloy 800 a matsayin "ƙasataccen lalata" a kowane mahallin ba. A cikin yanayin zafi mai zafi mai zafi, 800's chromium abun ciki da ma'auni na nickel suna ba da kyakkyawan iskar shaka da juriya na carburization, wanda shine dalilin da ya sa ya kasance daidaitaccen abu don gyarawa da kayan wuta. Garin yana ba da juriya na lalata gabaɗaya ga yawancin kafofin watsa labarai masu ruwa da tsaki kuma suna tsayayya da lalatawar damuwa a wurare da yawa.

Ƙayyadaddun yana bayyana lokacin da yanayin sabis ya haɗa da chlorides tare da rage acid, ko kuma lokacin da ɓarna da ɓarna ɓarna ke barazana ga aminci. A cikin waɗannan yanayi, rashin molybdenum na 800 ya bar shi da rauni ga harin da aka kai wanda aka tsara 825 don tsayayya. Aiki na gwaji akan sassan preheating tare da haɓakar chloride mai girma (5,500 ppm Cl⁻) a matsanancin zafin jiki ya gano cewa Incoloy 800 ya nuna lalatawar pitting yayin da Incoloy 825 ya nuna babu wani lalatawar saman ƙasa a ƙarƙashin yanayi guda. Irin wannan shaidar kwatankwacin, yayin da ta keɓance ga yanayin gwaji, yana kwatanta sakamako mai amfani na bambance-bambancen abun ciki.

Don an incoloy part a cikin ruwan teku mai sanyaya zafi, wannan bambanci yana da mahimmanci. Ruwan teku ya haɗu da chloride, rage yanayi na lokaci-lokaci daga ayyukan nazarin halittu, da fashe-fashe a flanges da haɗin gwiwar tube-to-tubesheet. Alloy 825's Mo da Cu abun ciki kai tsaye suna magance waɗannan hanyoyin. Alloy 800 ba ya aiki.

Siffofin Sashin Incoloy Na Musamman da Yanayin Aikace-aikacen

Incoloy Washers da Abubuwan Fastener

Masu wanki suna zaune a wani wuri marar gafara musamman a cikin haɗin gwiwa da aka kulle: an matse su a tsakanin saman biyu, suna haifar da raɗaɗi inda raguwar iskar oxygen da tattarawar chloride zai iya haɓaka harin. A cikin sabis na ɗaukar chloride, kayan wanki dole ne su yi tsayayya da lalata gabaɗaya da ɓarna yayin da ake ɗaukar kaya.

Alloy 825 washers sune ƙayyadaddun ƙayyadaddun ƙayyadaddun ƙayyadaddun haɗin kai a cikin gas mai tsami, ruwan teku, da tsarin sarrafa acid. Abubuwan da ke cikin molybdenum suna ba da juriya na lalata da ɓarna wanda 800 ba zai iya daidaitawa ba. Don aikace-aikacen hayaki mai zafi mai zafi ko tanderu inda chlorides ba ya nan kuma kwanciyar hankali na zafi shine fifiko, ana iya la'akari da wanki 800.

Ɗaya daga cikin bayanin kula mai amfani daga ƙwarewar machining: Incoloy alloys yana aiki mai ƙarfi yayin juyawa da zare, kuma ƙimar ƙarfin aiki don 825 yana da ɗan ƙaramin ƙarfi duk da cewa yana da ɗan ƙasa da na yau da kullun austenitic bakin karfe. Siraran wanki da ke ƙasa da kusan mm 1.5 na iya jujjuya yayin maganin zafi sai dai idan an goyan bayan gyaran da ya dace. Sau da yawa ana fi son jujjuya zaren maimakon taɓawa don ƙirar zaren wanki a cikin sabis na chloride, saboda taɓawa na iya haifar da lalacewar ƙasa wanda ya zama wurin farawa don lalatawar damuwa. Bayanan tabbatarwa: Wannan jagorar ƙirƙira yana nuna aikin mashin ɗin gabaɗaya don allunan Incoloy; ya kamata a tabbatar da takamaiman sigogi tare da ainihin masana'anta.

Incoloy Tube da Abubuwan Musanya Zafi

ASTM B423 / ASME SB423 yana rufe bututu mai aiki mai sanyi a cikin UNS N08825 don sabis na lalata gabaɗaya. A cikin tubing mai musayar zafi, zaɓi tsakanin 825 da 800 yawanci yana biye da sinadarai-gefen harsashi ko tube-gefen sunadarai.

Idan gefen bututu yana ɗaukar ruwa mai sanyaya tare da chlorides, ko kuma ruwan tsari ya ƙunshi rage acid, 825 bututu yana ba da gudummawar Mo da Cu da ake buƙata don tsayayya da harin rami da acid. Idan aikace-aikacen babban mai canza yanayin zafi ne ko tanderun pyrolysis inda yanayin ƙarfe ya wuce 600 ° C kuma yanayin ya bushe da gaske ko oxidizing, 800H ko 800HT bututu shine zaɓi na al'ada.

Halin tsaka-tsakin yanayi ya cancanci kulawa: masu musayar zafi tare da yanayin zafi a kusa da 400-500 ° C da matsakaicin matakan chloride. Duka alloy ba amsa ce ta duniya anan. Ya kamata yanke shawara ya kunna ko tattarawar chloride da ginshiƙan lissafi na ƙirƙira ingantaccen SCC ko haɗari. Idan eh, 825 mafi girman nickel da abun ciki na molybdenum suna ba da faffadan aminci.

Abubuwan da aka gyara na Valve Trim

Valve internals experience erosion-corrosion, crevice attack at sealing surfaces, and in sour service, sulfide stress cracking. Alloy 825 trim ana amfani da acid da m gas bar sabis inda hade da Mo for pitting juriya da Ni don SCC juriya ya dace. Alloy 800 ba shi da yawa a cikin sabis na bawul mai lalata amma yana bayyana a cikin iskar gas mai zafi da aikace-aikacen bawul ɗin tanderu.

Bayanan tabbatarwa: Ya kamata a tabbatar da kewayon samfurin da ake samu daga gidan yanar gizon kafin a nuna samuwar bawul datsa ko wani injin incoy sassa bayan washers. Idan hadayun rukunin yanar gizon na yanzu yana mai da hankali kan wanki, yakamata a karanta wannan sashe azaman mahallin aikace-aikacen maimakon da'awar samfur.

Teburin Zaɓuɓɓuka: Ta Matsakaici da Zazzabi

Tebu mai zuwa yana tattara dabaru na zaɓi cikin yanayin da aka saba fuskanta incoloy part masu saye. Yana ɗauka cewa ɓangaren wani abu ne mai ƙarfi ko na'ura (wanki, bututu, dacewa, datsa) kuma abin da ya fi damu shine lalata ruwa sai dai in an lura da shi.

Iyaka mai mahimmanci akan NACE MR0175: Wannan ma'auni yana magance juriya ga fashewar damuwa na sulfide kuma yana bayyana kayan da aka yarda da sabis na ɗauke da H₂S. Ba ya kafa iyakoki ko lalata. Abun da aka jera a cikin MR0175 ba shi da “cikakken juriya” ta atomatik ga duk yanayin tsami; yana nufin abu ya dace da buƙatun juriya a cikin ƙayyadaddun ƙayyadaddun iyaka. Don 825 a cikin brine mai tsami tare da babban chloride, juriya har yanzu ya dogara da abun ciki na Mo da ainihin zafin jiki da ƙwayar chloride. A cikin sabis na tsami mai girma-chloride, yarda da MR0175 wuri ne na farawa, ba cikakken kimanta lalata ba.

Abubuwan Ƙirƙira da Sayayya

Aiki Hardening da Machining

Alloy 825 da 800 duka suna aiki da sauri fiye da bakin karfe austenitic. Don 825 musamman, ƙimar ƙarfin aiki ya ɗan ɗan yi ƙasa da na gama-gari na austenitic amma har yanzu yana da girma, kuma dole ne a samar da kayan aikin da isasshe don rama don haɓaka ƙarfin amfanin gona yayin nakasawa. A cikin ayyukan injina, zama ko shafa kayan aiki a saman saman yana taurare yanki mai yanke kuma yana hanzarta lalacewa na kayan aiki. Don an incoloy part tare da matsananciyar haƙuri, kamar mai wanki tare da buƙatun flatness ko zaren dacewa, jerin mashin ɗin da hanyar kayan aiki yakamata su guje wa wucewar da ba dole ba wanda ke aiki a saman.

Wannan ba damuwa ce ta ka'idar don sassan bakin ciki ba. Masu wanki da ke ƙasa da kauri na mm 1.5 na iya jujjuya yayin warware matsalar ko maganin zafi na ƙarshe idan ba a tallafa musu da kyau ba. Manyan masu wanki na diamita na iya buƙatar ƙimar sanyaya mai sarrafawa don gujewa wargaɗi. Waɗannan cikakkun bayanai ne na ƙirƙira waɗanda yakamata a tattauna su a matakin zance, ba a gano su ba yayin binciken labarin farko.

Ƙarshen Sama da Tasirinsa akan Juriyar Lalacewa

Rushewar rami da ɓarna suna farawa a kan ƙarewar ƙasa: tarkace, ƙarfe da aka haɗa, baƙar zafi daga walda, da saman injina. Don sassa 825 a cikin sabis na chloride, yanayin saman fuskokin rufe fuska da filaye masu ƙira suna shafar rayuwar sabis kai tsaye.

Ƙarshen injin da aka yi na Ra ≤ 0.8 µm ya zama na yau da kullun don juriyar lalata gabaɗaya. Electropolishing zuwa Ra ≤ 0.2 µm ƙila a keɓance shi don mahimman abubuwan rufewa a cikin sabis na sinadarai ko tsaftataccen tsafta, inda ake buƙatar juriyar lalata da tsafta. Ga masu wanki a cikin ruwan teku ko sabis na tsami, cire tint mai zafi da tabbatar da tsaftataccen wuri mai wucewa bayan yin injin ya fi mahimmanci fiye da samun lambar Ra mai ƙarancin ƙarfi.

Daidaito da Takaddun Shaida

Lokacin siyan wani incoloy part, ya kamata a tabbatar da takardar shaidar kayan bisa ƙayyadadden lambar UNS da ma'auni:

• Farashin 825Saukewa: N08825. Ana iya ƙayyade Tube da bututu zuwa ASTM B423 / ASME SB423. Bar da fom ɗin ƙirƙira sun faɗi ƙarƙashin ƙayyadaddun bayanai daban-daban dangane da sigar samfur. Ya kamata a bayyana yarda da NACE MR0175 a sarari akan takardar shaidar idan ana buƙatar sabis na tsami.
• Alloy 800: UNS N08800 (ko N08810/N08811 na 800H/800HT). Ka'idojin samfur sun bambanta ta hanyar tsari; hannun jari, faranti, da na jabu kowanne yana da keɓaɓɓen ɗaukar hoto na ASTM.

Shafin samfurin wankin Incoloy na gidan yanar gizon yana nuna iyawa wajen yin injin wankin Incoloy zuwa ƙayyadaddun haƙuri da ƙarewar saman. Don wasu nau'ikan nau'ikan nau'ikan nau'ikan bututu ko na'urori na al'ada, yakamata a tabbatar da iyawar masana'anta kai tsaye maimakon ɗauka daga shafin wanki.

FAQ

Shin Incoloy 825 koyaushe shine mafi kyawun zaɓi don sabis na lalata idan aka kwatanta da 800?
A'a. Alloy 825 shine mafi kyawun zaɓi lokacin da sabis ɗin ya ƙunshi chlorides, rage acid, ko iskar gas mai tsami, saboda ƙarin Mo da Cu suna fuskantar waɗannan hanyoyin. Alloy 800 ya fi dacewa kuma ya fi dacewa da tattalin arziƙi don yanayin zafi mai zafi ko ƙonawa inda zafi ke haifar da lalata maimakon sunadarai masu ruwa. Yin amfani da 825 a cikin aikace-aikacen tanderu mai zafi zai ƙara farashi ba tare da ƙara aiki ba.

Shin za a iya amfani da masu wanki na Incoloy 800 a cikin flanges na ruwan teku?
Ba a ba da shawarar ba. Ruwan teku yana haifar da yanayi mara kyau a fuskokin masu wanki da matakan chloride waɗanda ke haɓaka rami. Alloy 800 ba ya ƙunshi ƙarin molybdenum na niyya, wanda shine farkon abin haɗawa da juriya a cikin kafofin watsa labarai na chloride. Alloy 825 washers suna ba da abun ciki na Mo da ake buƙata don wannan sabis ɗin.

Menene amincewar NACE MR0175 a zahiri yana nufin ɓangaren Incoloy 825?
Yana nufin kayan ya cika daidaitattun buƙatun don juriya ga faɗuwar damuwa na sulfide a cikin mahalli masu ɗauke da H₂ a cikin ƙayyadaddun iyaka na daidaitattun. Ba ya tabbatar da juriya ga rami, ɓarna ɓarna, ko ɓarnar asarar nauyi gabaɗaya. Wani sashi na iya zama mai yarda da MR0175 kuma har yanzu yana fama da pitting a cikin babban chloride m brine idan abun ciki na Mo da yanayin saman bai dace da takamaiman yanayi ba.

Shin ASTM B423 yana rufe Incoloy 825 washers?
No. ASTM B423 yana rufe bututu da bututu maras sumul a cikin UNS N08825. Ana siyan masu wanki da sauran nau'ikan injina akan takardar shedar kayan aiki da ke nuna lambar UNS da sinadarai maimakon ma'auni na nau'in samfur don wanki. Ya kamata takardar shaidar ta tabbatar da N08825 chemistry da duk wani abin da ake buƙata na NACE.

Me yasa ƙarewar saman ke da mahimmanci ga ɓangaren Incoloy a cikin sabis na chloride?
Ramuka suna farawa da lahani na saman inda chlorides ke tattarawa da wadatar iskar oxygen ya bambanta da yanayin girma. Mummunar saman injina, baƙar zafi, ko ɓangarori na waje suna haifar da rukunin farawa. Don 825 a cikin ruwan teku ko gishiri mai tsami, ƙayyadaddun wuri mai tsabta, daɗaɗɗen da ya dace akan hatimi da filaye masu fuskantar ƙuri'a hanya ce mai amfani don tallafawa juriyar lalata ta gami.

Daidaita Alloy zuwa Sabis

Zaɓi tsakanin Incoloy 825 da 800 don wani incoloy part ya kamata a bi tsarin lalata mafi girma a cikin ainihin yanayin sabis. Idan chlorides, rage acid, ko H₂S suna nan kuma sashin zai yi aiki a cikin ruwa mai ruwa ko rigar muhalli, 825's molybdenum, jan ƙarfe, da abun ciki na nickel suna magance waɗannan takamaiman barazanar. Idan aikace-aikacen yana da iskar oxygen mai zafi, carburization, ko sabis ɗin tanderun bushewa, 800 ko bambance-bambancen ƙarfinsa mafi girma shine dangin da suka dace.

Don masu wanki da abubuwan da aka ƙera a cikin sabis na ɓarna, zaɓin zaɓin ya kamata kuma a ba da lissafin lissafi na ƙirƙira, ƙarewar ƙasa, da cikakkun bayanan ƙirƙira waɗanda ke tantance ko ƙayyadadden gami yana aiki kamar yadda aka yi niyya. Ƙwararren mai wanki 825 tare da ƙarancin ƙarewa na iya gazawa a cikin sabis na chloride kamar yadda mai wanki 800 da aka gama da kyau ba zai iya maye gurbin 825 ba inda ake buƙatar molybdenum.

Don yin bitar ƙayyadaddun ƙayyadaddun ƙayyadaddun kayan wanki na Incoloy, gami da maki maki, juriya, da zaɓin gama ƙasa, ziyarci shafin samfurin wankin Incoloy. Don wani sashi da ya wuce wanki, tabbatar da iyakar masana'anta kai tsaye kafin tantancewa.