Indandatho ye-piston isebenza endaweni yokushisa ephezulu, umfutho ophakeme, isivinini esikhulu, kanye nendawo yokusebenza engagcotshisiwe kahle. Ngesikhathi esifanayo, kufanele ibe nomsebenzi omuhle wokuvala, ukukhuhla uwoyela, nemisebenzi yokuqhuba ukushisa. Kufanele iqinisekise ukusebenza kwayo kokuvala futhi ivimbele indandatho ye-piston ukuthi ingabambeki kuma-Grooves namasilinda, ngakho-ke kufanele kube nezikhala ezintathu lapho ufaka iringi ye-piston.

Kunezikhala ezintathu ezizokalwa uma kufakwa indandatho yepiston, okungukuthi, izikhala ezintathu zeringi yepiston ngamafuphi. Eyokuqala igebe lokuvula, okwesibili igebe le-axial (i-side clearance), kanti eyesithathu igebe le-radial (igebe elingemuva). Ake sethule indlela yokulinganisa ye-piston ring izikhala ezintathu:

Igebe lokuvula
Imbobo iyisikhala seringi ye-piston kanye nokuvuleka ngemuva kokuthi indandatho ye-piston ifakwe kusilinda ukuvimbela iringi ye-piston ukuthi ingabambeki ngemuva kokushiswa nokunwetshwa. Lapho ubheka igebe lokuphela kweringi ye-piston, faka indandatho ye-piston kusilinda bese uyiphusha ngaphezulu kwepiston. Bese ukala igebe ekuvuleni ngegeji yokujiya, ngokuvamile engu-0.25 ~ 0.50mm. Ngenxa yokushisa okuphezulu kokusebenza, igebe lokugcina lendandatho yokuqala likhulu kunelezinye izindandatho.

Igebe eseceleni
Igebe elisemaceleni libhekisela esikhaleni esingenhla nesingezansi seringi ye-piston emseleni oyindandatho. Igebe eliseceleni eliningi lizothinta umphumela wokuvala we-piston, indandatho encane kakhulu ye-gap eseceleni izobhajwa emseleni. Ngesikhathi sokulinganisa, indandatho yepiston ifakwa emseleni oyindandatho futhi ikalwe ngegeji yokujiya. Ngenxa yezinga lokushisa eliphezulu lokusebenza, inani leringi yokuqala ngokuvamile li-0.04 ~ 0.10mm, kanti lezinye izindandatho zegesi ngokuvamile liba ngu-0.03 ~ 0.07mm. alikho igebe elihlangothini lendandatho yamafutha ehlanganisiwe.

Igebe elingemuva
Igebe elingemuva lisho igebe eliphakathi kwengemuva leringi ye-piston kanye naphansi kwe-piston ring groove ngemva kokufakwa kwepiston kusilinda. Ngokuvamile kuvezwa umehluko phakathi kokushona kwemisele kanye nogqinsi lwendandatho, okuvamise ukuba ngu-0.30 ~ 0.40mm. Igebe elingemuva lamasongo kawoyela ajwayelekile likhulu. Umkhuba ojwayelekile ukufaka indandatho yepiston emseleni. Uma iphansi kunebhange leringi, ingazungeziswa ngokukhululeka ngaphandle kokuzizwa ihlaba.