Ma muli o ka nānā ʻana i nā kumu kumu o ka ʻaʻahu, ʻo ka ʻāpana "cylinder liner-piston ring" o ka ʻenekini moana e pili ana i nā ʻano lole maʻamau ʻehā:

(1) ʻO ka ʻaʻahu luhi e pili ana i ke ʻano o ka hoʻoulu ʻana o ka friction i ka deformation nui a me ke koʻikoʻi ma ka wahi pili, a hana ʻia nā māwae a luku ʻia. ʻO ka ʻaʻahu luhi no ka nalo ʻana o nā ʻāpana mechanical i loko o ke ʻano maʻamau;

(2) ʻO ka ʻaʻahu abrasive he mea ia e hiki ai i nā ʻāpana paʻakikī ke kumu i ka abrasion a me ka hāʻule ʻana o nā mea ʻili ma luna o ka ʻili o ka paʻa paʻa. ʻO ka ʻaʻahu abrasive nui e poni i ka paia cylinder o ka mīkini, e alakaʻi pololei ana i ka paʻakikī o ka hoʻokumu ʻana i kahi kiʻi ʻaila paʻa ma ka ʻili o ka paia cylinder o ka aila lubricating, e hoʻonui ai i ka lole. ʻO ka alumini a me ke silika i ka wahie ke kumu nui o ka lole abrasive;

(3) Ma muli o ka "adhesion" ma luna o ka ʻili o ka paʻi paʻa i ka wā e piʻi ai ke kaomi o waho a i ʻole ka hāʻule ʻana o ka mea lubricating. ʻO kaʻaʻahu adhesion heʻano koʻikoʻi loa ia o kaʻaʻahu, kahi e alakaʻi ai i kaʻiliʻana o ka uhi i hanaʻia i nā mea kūikawā ma kaʻili o ka cylinder liner a hoʻopilikia nui i ka hana maʻamau o ka mīkini;

(4) ʻO ka ʻaʻahu corrosion e pili ana i ke ʻano o ka nalo waiwai i hoʻokumu ʻia e ke kemika a i ʻole ka hopena electrochemical ma waena o ka ʻili o ka ʻili a me ke ʻano a puni i ka wā o ka neʻe ʻana o nā ʻili o ka lua friction. I ka hihia o ka ʻinoʻino koʻikoʻi, e ʻili ka mea ʻili o ka paia cylinder a pili i ka lole. ʻO ka hoʻoholo ʻana i nā ʻano friction ma luna aʻe he mea nui ia no ke aʻo ʻana i nā ʻano friction o nā hui friction aila moana ma lalo o nā kūlana o ka wahie sulfur haʻahaʻa a me ka haʻahaʻa haʻahaʻa, e ʻimi ana i ke kumumanaʻo e hōʻemi i ka lole a hoʻolōʻihi i ke ola lawelawe o nā ʻāpana mīkini. ʻO nā ʻano friction ma luna aʻe ka mea nui i loko o ka lubrication hui ʻia a me nā wahi lubrication palena. Ma ka hoʻomaikaʻi ʻana i ka nui o nā mea hoʻohui, hiki ke hoʻomaikaʻi ʻia ke kūpaʻa ʻana o ka mechanical a me ka corrosion wear resistance o ka aila lubricating, a hiki ke hoʻolōʻihi ʻia ke ola lawelawe o nā ʻāpana mechanical i ka hana maoli.