Isitokhwe semibhobho yentsimbi engenamthungoI-ASTM A335 P91, umbhobho wentsimbi ongenamthungo osetyenziswa kwiityhubhu zebhoyila, iityhubhu zokutshintshiselana ngobushushu kunye namanye amashishini, ingasetyenziswa njengemibhobho yentsimbi kwizifudumezi ezinobushushu obuphezulu kunye nezifudumezi kwibhoilers ezingaphantsi kunye neziphezulu ezinobushushu bodonga ≤625 °C, kunye nodonga olunobushushu obuphezulu bentloko kunye nemibhobho yomphunga enamaqondo obushushu ≤600℃ ingasetyenziswa njengezixhobo zokutshintsha ubushushu bamandla enyukliya kunye neetyhubhu zesithando somlilo se-petroleum.
I-ASTM A335 P91 yintsimbi yobushushu obuphezulu obuyintsimbi ephantsi kwe-alloy chromium-molybdenum. Isetyenziswa ngokubanzi kwimibhobho kunye nezixhobo eziphantsi kobushushu obuphezulu kunye noxinzelelo oluphezulu, njengepetrochemical, amandla ombane, izityalo zamandla enyukliya kunye nezinye iindawo. Amacandelo aphambili ale nto yi-chromium, i-molybdenum, ithusi, i-manganese, i-silicon, i-phosphorus, isulfure kunye nezinye izinto. Umxholo we-chromium kunye ne-molybdenum uphezulu kakhulu, unokuphucula ukuxhathisa ubushushu obuphezulu kunye nokumelana ne-oxidation yezinto.
Izinto ze-ASTM A335 P91 zineempawu ezibalaseleyo zoomatshini kwaye zisenokugcina amandla amahle kunye nokuqina phantsi kobushushu obuphezulu kunye noxinzelelo oluphezulu. Izinto eziphathekayo nazo zichasene kakhulu ne-oxidation, enokwandisa ngokufanelekileyo ubomi benkonzo yemibhobho kunye nezixhobo. Ukongeza, izinto eziphathekayo zinokusebenza kakuhle kwe-welding, ukwenza ukwakhiwa kunye nokugcinwa kube lula.
Ngenxa yokuba izinto ze-ASTM A335 P91 zinezi mpawu zibalaseleyo, zisetyenziswa ngokubanzi kwiindawo ezithile zobushushu obuphezulu kunye noxinzelelo oluphezulu. Ngokomzekelo, kwishishini le-petrochemical, imibhobho kunye nezixhobo ezenziwe nge-ASTM A335 P91 inokumelana nokukhukuliseka kweekhemikhali kunye ne-corrosion phantsi kwamaqondo aphezulu kunye noxinzelelo, ukuqinisekisa ukusebenza ngokukhuselekileyo kwezixhobo. Kwimimandla yamandla ombane kunye nezityalo zamandla enyukliya, imibhobho kunye nezixhobo ezenziwe nge-ASTM A335 P91 inokumelana nokubola kunye nokukhukuliseka komphunga kunye nomphunga wamanzi kunye neminye imithombo yeendaba phantsi kobushushu obuphezulu kunye noxinzelelo, ukuqinisekisa ukusebenza okuqhelekileyo kwezixhobo.