Wahi a ka mea sila ʻili,nā kiwikā pukahiki ke hoʻokaʻawale ʻia i ʻelua ʻano: sila paʻakikī a me sila palupalu. He aha ka ʻokoʻa ma waena o kahi valve sila palupalu a me kahi valve sila paʻakikī:
ʻO ka valve puka sila paʻa: ʻO nā mea sila ma nā ʻili sila ʻelua he mau mea metala, i kapa ʻia ʻo "sila paʻa". Ke kūpaʻa wela kiʻekiʻe, ke kūpaʻa ʻaʻahu, nā waiwai mechanical maikaʻi e like me: kila + kila; kila + keleawe; kila
+ Graphite; kila + kila huila. ʻO nā mea sila i hoʻohana pinepine ʻia: kila kila 13Cr, nā mea huila paʻakikī, tungsten carbide i pīpī ʻia, a pēlā aku. ʻAʻole i sila maikaʻi ʻia ka ʻili sila.
ʻO ka puka sila palupalu: ua hana ʻia ka hui sila me nā mea metala ma kekahi ʻaoʻao a me nā mea ʻaʻole metala elastic ma kekahi ʻaoʻao, i kapa ʻia ʻo "sila palupalu". Maikaʻi ka hana sila o kēia ʻano sila, akā ʻaʻole ia e kū i ka mahana kiʻekiʻe, maʻalahi ke komo, a he mau waiwai mechanical maikaʻi ʻole. E like me: kila + laholio; kila + PTFE, a pēlā aku. ʻO ia hoʻi, ua hana ʻia kekahi ʻaoʻao o ka hui sila me nā mea me ka paʻakikī haʻahaʻa. Ma ke ʻano laulā, ua hana ʻia ka noho sila palupalu me nā mea ʻaʻole metala me kekahi ikaika, paʻakikī a me ke kūpaʻa wela. Loaʻa iā ia ka hana sila maikaʻi a hiki ke hoʻokō i ka leakage ʻole, akā he lōʻihi kona ola. Ke hoʻohālikelike ʻia me ka hoʻololi maikaʻi ʻole i ka mahana, ua hana ʻia ka sila paʻakikī me ka metala, a he haʻahaʻa ka hana sila, ʻoiai ke koi nei kekahi mau mea hana hiki ke hoʻokō i ka leakage ʻole. ʻO ke kumu o ka hana ʻana o ka valve puka sila palupalu: e hoʻoponopono i ka pilikia o ka noho valve a me ka ʻili sila o ka papa valve i ʻānai ʻia a hoʻololi ʻia paha, hiki i ka papa valve ke uku koke no ka uhi paʻa paʻa a me ke kaulike kaomi me ka valve puka sila palupalu, a e hoʻoponopono i ka pilikia o ka mea sila palupalu i hōʻino ʻia e ka friction. ʻO ka pilikia o ka ʻili sila, no ka mea hiki ke hoʻololi ʻia ka lima sila o ka valve puka, e hoʻonui nui ana i ka hoʻohana ʻana o ka valve.
ʻO ka laulā kūpono o ka valve puka sila palupalu: ke anawaena (p50-p400mm, kaomi 2.5-4.0MPa, nā wai mahana maʻamau like ʻole ma lalo o 200 ℃).
ʻAʻole hiki i ka sila palupalu ke hoʻokō i nā koi hana no kekahi mau mea ʻino, a hiki i ka sila paʻakikī ke hoʻoponopono iā ia!
Hiki i kēia mau ʻano sila ʻelua ke hoʻokō kekahi i kekahi. Ma ke ʻano o ka paʻa, maikaʻi iki ka sila palupalu, akā i kēia manawa hiki i ka paʻa o ka sila paʻakikī ke hoʻokō i nā koi like! ʻO ka pōmaikaʻi o ka sila palupalu he hana sila maikaʻi, akā ʻo ka hemahema, maʻalahi ke ʻelemakule, ʻaʻahu ʻia, a he ola lawelawe pōkole. He lōʻihi ke ola lawelawe o ka sila paʻakikī, akā ʻoi aku ka ʻino o ka paʻa ma mua o ka sila palupalu.