Mu makina otumizira madzimadzi, valavu ndi chinthu chofunikira kwambiri chowongolera, chomwe chimakhala ndi ntchito zowongolera, kusokoneza, kutsutsa-kubwerera, kudulidwa, ndi shunt. Valve imagwiritsidwa ntchito kwambiri m'mafakitale ndi anthu. Valavu yotentha kwambiri ndi mtundu womwe umagwiritsidwa ntchito kwambiri m'mavavu. Makhalidwe ake enieni ndi awa: ntchito yabwino yozimitsa, kuzimitsa kwakuya kungathe kuchitidwa; weldability wabwino; kuyamwa bwino kwamphamvu, ndikovuta kuwononga ndi chiwawa; Kupsa mtima kumakonda kukhala kochepa ndi zina zotero. Pali mitundu yambiri ya ma valve otentha kwambiri. Zofala kwambiri ndizotentha kwambirivalavu butterfly, kutentha kwambiri ma valve a mpira, zosefera zotentha kwambiri, komanso kutentha kwambiri ma valve pachipata.

Ma valve otenthetsera kwambiri amaphatikizapo ma valve olowera pachipata, ma valve otsekera kutentha kwambiri, ma valve oyendera kutentha kwambiri, ma valve othamanga kwambiri, agulugufe otentha kwambiri, ma valve a singano a kutentha kwambiri, ma valve othamanga kwambiri, ndi ma valve ochepetsera kutentha kwambiri. Zina mwa izo, zomwe zimagwiritsidwa ntchito kwambiri ndi ma valve a zipata, ma valve a globe, ma valve oyendera, ma valve a mpira ndi ma valve a butterfly.

Kutentha kwakukulu komwe kumagwirira ntchito kumaphatikizapo kutentha kwapansi, kutentha kwambiri Ⅰ, kutentha kwakukulu Ⅱ, kutentha kwakukulu Ⅲ, kutentha kwakukulu Ⅳ, ndi kutentha kwakukulu Ⅴ, zomwe zidzayambitsidwe mosiyana pansipa.

1. Kutentha kocheperako

Kutentha kwakukulu kumatanthauza kuti kutentha kwa valve kuli m'dera la 325 ～425 ℃. Ngati sing'anga ndi madzi ndi nthunzi, WCB, WCC, A105, WC6 ndi WC9 amagwiritsidwa ntchito makamaka. Ngati sing'anga ndi mafuta sulfure munali, C5, CF8, CF3, CF8M, CF3M, etc., amene kugonjetsedwa ndi dzimbiri sulfide, makamaka ntchito. Amagwiritsidwa ntchito kwambiri pazida zam'mlengalenga komanso zochepetsera kupanikizika komanso zida zochedwa zokokera m'malo oyeretsera. Panthawi imeneyi, mavavu zopangidwa CF8, CF8M, CF3 ndi CF3M si ntchito dzimbiri kukana njira asidi, koma ntchito mankhwala sulfure munali mafuta ndi mapaipi mafuta ndi mpweya. Mu chikhalidwe ichi, pazipita ntchito kutentha kwa CF8, CF8M, CF3 ndi CF3M ndi 450 ° C.

2. Kutentha kwakukulu Ⅰ

Pamene kutentha kwa valve ndi 425 ～550 ℃, ndi kalasi yotentha kwambiri I (yotchedwa PI class). Zachikulu za PI kalasi valavu ndi "mkulu kutentha Ⅰ kalasi sing'anga mpweya chromium faifi tambala osowa dziko titaniyamu apamwamba kutentha zosagwira zitsulo" ndi CF8 monga mawonekedwe zofunika mu ASTMA351 muyezo. Chifukwa kalasi ya PI ndi dzina lapadera, lingaliro la chitsulo chosapanga dzimbiri (P) chapamwamba kwambiri likuphatikizidwa pano. Choncho, ngati sing'anga ntchito ndi madzi kapena nthunzi, ngakhale mkulu-kutentha zitsulo WC6 (t≤540 ℃) kapena WC9 (t≤570 ℃) angagwiritsidwenso ntchito, pamene mankhwala mafuta sulfure angagwiritsidwenso ntchito mkulu-kutentha zitsulo. C5 (ZG1Cr5Mo), koma Sangatchulidwe kuti PI-class pano.

3. Kutentha kwakukulu II

Kutentha kwa ntchito ya valve ndi 550 ～650 ℃, ndipo imatchedwa kutentha kwambiri Ⅱ (kutchedwa P Ⅱ). PⅡ valavu yotentha kwambiri imagwiritsidwa ntchito makamaka pazida zopangira mafuta olemetsa. Lili ndi valavu yachipata yotchinga kutentha kwambiri yomwe imagwiritsidwa ntchito pozungulira katatu ndi mbali zina. Chuma chachikulu cha PⅡ valavu kalasi ndi "kutentha kwambiri Ⅱ kalasi sing'anga carbon chromium faifi tambala osowa dziko titaniyamu tantalum analimbitsa kutentha zosagwira zitsulo" ndi CF8 monga mawonekedwe zofunika mu ASTMA351 muyezo.

4. Kutentha kwakukulu III

Kutentha kwa ntchito ya valve ndi 650 ～730 ℃, ndipo imatchedwa kutentha kwambiri III (kutchedwa PⅢ). P Ⅲ ma valve okwera kwambiri amagwiritsidwa ntchito makamaka m'magawo akuluakulu opangira mafuta olemetsa m'malo oyeretsera. Nkhani yaikulu ya PⅢ kalasi valavu mkulu kutentha ndi CF8M zochokera ASTMA351.

5.Kutentha kwakukulu Ⅳ

Kutentha kwa ntchito ya valve ndi 730 ～816 ℃, ndipo idavoteredwa ngati kutentha kwambiri IV (kutchedwa PIV mwachidule). Malire apamwamba a kutentha kwa ntchito ya valve ya PIV ndi 816 ℃, chifukwa kutentha kwapamwamba kwambiri koperekedwa ndi muyezo wa ASEMEB16134 wothamanga-kutentha wosankhidwa kuti apange ma valve ndi 816 ℃ (1500υ). Komanso, pambuyo kutentha ntchito kuposa 816 ° C, zitsulo ali pafupi kulowa m'dera forging kutentha. Panthawiyi, zitsulo zili m'dera la pulasitiki, ndipo zitsulo zimakhala ndi pulasitiki yabwino, ndipo zimakhala zovuta kupirira kupanikizika kwakukulu kwa ntchito ndi mphamvu zowonongeka ndikuzisunga kuti zisawonongeke. Zinthu zazikulu za P Ⅳ valavu ndi CF8M mu muyezo ASTMA351 monga maziko a mawonekedwe "mkulu kutentha Ⅳ sing'anga mpweya chromium faifi tambala molybdenum osowa dziko titaniyamu tantalum analimbitsa kutentha zosagwira zitsulo". CK-20 ndi ASTMA182 muyezo F310 (kuphatikiza C zomwe zili ≥01050%) ndi F310H zitsulo zosapanga dzimbiri zosapanga dzimbiri.

6, kutentha kwambiri Ⅴ

Kutentha kwa valavu ndipamwamba kuposa 816 ℃, komwe kumatchedwa PⅤ, PⅤ valavu yotentha kwambiri (kwa mavavu otseka, osayang'anira ma valve a butterfly) ayenera kutengera njira zamakono zopangira, monga zitsulo zotchinga kapena madzi kapena mpweya wozizira. onetsetsani kuti valve ikugwira ntchito bwino. Choncho, malire apamwamba a kutentha kwa ntchito ya PⅤ kalasi yotentha kwambiri ya valve sichinatchulidwe, chifukwa kutentha kwa ntchito ya valve yolamulira sikungotsimikiziridwa ndi zakuthupi, koma ndi njira zapadera zopangira, ndi mfundo yaikulu ya njira yopangira. ndi chimodzimodzi. PⅤ valavu yapamwamba yotentha imatha kusankha zipangizo zomveka zomwe zingathe kukumana ndi valve malinga ndi sing'anga yake yogwirira ntchito komanso kuthamanga kwa ntchito ndi njira zapadera zopangira. Mu gulu la PⅤ valavu yotentha kwambiri, nthawi zambiri valavu ya flapper kapena butterfly valve ya flue flapper valve kapena butterfly valve nthawi zambiri imasankhidwa kuchokera ku HK-30 ndi HK-40 high-temperature alloys mu ASTMA297 standard. Kulimbana ndi dzimbiri, koma osatha kupirira kugwedezeka ndi kupsinjika kwakukulu.