Biraha birta ah ee midabka birta ah, rullalulatu-dahaarka leh waxay u adeegi karaan alaab cayriin ah oo loogu talagalay mashiinnada dharka -gaar ahaan, samaynta daboolkooda dibadda. PCM birta hore loo dahaadhay (badanaa loogu yeero si fudud "Birta PCM" ee alaab-qeybiyeyaashu) waa shay tayo sare leh oo inta badan loo isticmaalo qolka kabadhka ee mishiinnada dharka dhaqda ee qaaliga ah. Dusha hore ee wejiga hore waxa ay ka kooban tahay nidaam daahan oo ku salaysan toosan, xabagta polyester-ka saliida-la'aanta ah, oo lagu xoojiyey xabagta amino si gaar ah loo habeeyey iyo kicinta si loo hubiyo dabacsanaan ku filan iyo waxqabad foorarsi. Qaybtan birta hore loo rinjiyeeyay-ay ku jirto birta PCM-waxaa si wayn u qaata soosaarayaasha talaajadaha,mashiinada dharka,iyo agabka kale ee guriga si loogu soo saaro qaybo kala duwan oo dibadda ah. Intaa waxaa dheer, go'yaal bir ah oo horay loo rinjiyeeyay ayaa lagu soo saaray iyadoo la isticmaalayo birta qabow-duuban ama galvanized substrate ahaan. Nidaamku wuxuu ku lug leeyahay daawayn dusha sare ah (hoos-u-dhigid, nadiifin, iyo beddelaad kiimikaad), oo ay ku xigto codsiga joogtada ah ee rinjiga iyada oo loo marayo dahaarka rullalulatada, iyo ugu dambeyntii, dubista iyo qaboojinta. Badeecadu waa mid fudud, qurux ahaan, oo aad u adkaysata daxalka; Waxaa intaa dheer, si toos ah ayaa loo farsamayn karaa oo loo samayn karaa, taas oo ka dhigaysa mid ku habboon samaynta qalabka sida mashiinka dharka. Sidaa darteed, waa haddii shuruudaha ku saabsan iska caabbinta miridhku, adkeysiga, iyo shuruudaha waxqabadka kale la buuxiyo, xaashida birta ah ee midabka birta ah, dahaarka leh ayaa runtii ah walxo ceeriin ah oo wax soo saarka.