Magulu ozungulira singano ndi ma khola ndi mayunitsi amodzi kapena awiri okhala ndi makhola ndi ma roller a singano. Popeza kutalika kwa kapangidwe kawo ka radial kumangogwirizana ndi kukula kwa ma roller a singano, magulo ozungulira singano ndi ma khola angagwiritsidwe ntchito kupanga ma bearing ndi envelopu yocheperako ya kapangidwe ka radial. Ndi mayunitsi athunthu okhala ndi khola ndi ma roller a singano.
