Ma waho aʻe o nā paipu kila maʻamau, nā paipu kila paila haʻahaʻa a me ke kaumaha waena, nā paipu kila paila kiʻekiʻe, nā paipu kila huila, nā paipu haki petroleum, a me nā paipu kila ʻē aʻe, aia pū kekahi i loko o nā paipu kila wili anu ʻōwili anu nā paipu kila lahilahi kalapona a me nā paipu kila lahilahi me nā paipu kila. ʻOi aku ka nui o ke anawaena o waho o nā paipu kila wela ma mua o 32mm, a ʻo ka mānoanoa o ka paia he 2.5-75mm. Hiki i ke anawaena o nā paipu kila wili anu ʻōwili anu a hiki i ka 6mm, a hiki i ka mānoanoa o ka paia a hiki i ka 0.25mm. Hiki i ke anawaena o waho o nā paipu lahilahi a hiki i ka 5mm, a ʻoi aku ka liʻiliʻi o ka paia ma mua o 0.25mm. ʻOi aku ka pololei o ka ʻōwili anu ma mua o ka ʻōwili wela, ʻoiai ʻo nā paipu kila wili anu i huki anu ʻia e hoʻohana pinepine ʻia e hana i nā ʻāpana mīkini.