ʻO ka mea nui o ka mea hoʻoheheʻe kemika o nā pahu lana ka oxide o ke silika a me ka alumini, kahi o ka ʻike o ka silicon dioxide ma kahi o 50-65%, a ʻo ka ʻike o ka alumini oxide ma kahi o 25-35%.No ka mea he kiʻekiʻe ka helu heheʻe o ka silica e like me 1725 ℃ a ʻo ka alumina he 2050 ℃, he mau mea refractory kiʻekiʻe lākou a pau.No laila, he kiʻekiʻe loa ka refractoriness o nā pahu lana, ma ke ʻano he 1600-1700 ℃, e hana ana iā lākou i nā refractory kiʻekiʻe.ʻO ke kaumaha māmā, ka wela wela.ʻO ka paia pele e lana ana he lahilahi a hakahaka, he semi vacuum ka lua, he wahi kinoea liʻiliʻi wale nō (N2, H2 a me CO2, a me nā mea ʻē aʻe), a lohi a liʻiliʻi loa ka hoʻoiho wela.No laila, ʻaʻole māmā wale ke kaumaha o nā pahu lana (ka nui o ke kaumaha 250-450 kg / m3), akā maikaʻi nō hoʻi i ka insulation thermal (thermal conductivity 0.08-0.1 i ka lumi wela), kahi e hoʻokumu ai i ke kumu no lākou e pāʻani i kahi kuleana koʻikoʻi. ma ke kahua o nā mea hoʻoheheʻe wela māmā.

ʻO ka paʻakikī kiʻekiʻe a me ka ikaika.No ka mea, he kino aniani paʻakikī ka pahu lana i hoʻokumu ʻia e ka silica alumina mineral phase (quartz a mullite), hiki i kona paʻakikī ke hiki i Mohs 6-7, hiki ke piʻi ka ikaika static i 70-140mpa, a ʻo kona ʻano maoli ʻo 2.10-2.20g/cm3 , ua like ia me ka pohaku.No laila, loaʻa ka ikaika kiʻekiʻe o nā pahu lana.ʻO ka maʻamau, ʻo nā mea porous māmā a i ʻole nā ​​​​mea hollow e like me ka perlite, ka pōhaku paila, ka diatomite, sepiolite a me ka vermiculite i hoʻonui ʻia he ʻano paʻakikī a ikaika.ʻO nā huahana insulation thermal a i ʻole nā ​​​​huahana refractory māmā i hana ʻia mai lākou mai ka hemahema o ka ikaika maikaʻi ʻole.ʻO ko lākou mau hemahema, ʻo ia wale nō ka ikaika o nā pahu lana, no laila, ʻoi aku ka maikaʻi o ka hoʻokūkū a me ka hoʻohana ākea ʻana o nā pahu lana.Maikaʻi ka nui o ka ʻāpana a ua nui ka ʻāpana kiko.ʻO 1-250 μ M ka nui maoli o ka nui maoli o nā pahu lana.No laila, hiki ke hoʻohana pololei ʻia nā pahu lana me ka ʻole o ka wili ʻana.

Hiki i ka Fineness ke hoʻokō i nā pono o nā huahana like ʻole, ʻo nā mea ʻē aʻe māmā ʻē aʻe ka nui o ka nui o ka nui (e like me ka perlite, a me nā mea ʻē aʻe), inā e hoʻonui nui ka wili ʻana i ka hiki, no laila e hoʻemi nui ʻia ka insulation thermal.Ma kēia ʻano, loaʻa nā pōmaikaʻi o nā lei lana.ʻOi aku ka maikaʻi o ka pale uila.ʻO nā pahu lana he mau mea insulating maikaʻi loa a ʻaʻole-conductive.ʻO ka mea maʻamau, hoʻemi ke kūʻē o ka insulator me ka piʻi ʻana o ka mahana, akā piʻi ke kūʻē o ka bead lana me ka piʻi ʻana o ka mahana.ʻAʻole loaʻa kēia pono i nā mea insulating ʻē aʻe.No laila, hiki iā ia ke hana i nā huahana insulation ma lalo o nā kūlana wela kiʻekiʻe.