track roller frame
/ˈtɹak ˈɹəʊlə ˈfɹeɪm/
n
English · track roller frame中文 · 履带支重轮架Español · bastidor de los rodillosFrançais · longeron de chenille
意味：Lengthwise part forming the track’s chassis; the final drive and the track idler are attached to it.