The track roller is composed of shell,collar,shaft,seal,O-ring,bushing bronze,plug,lock pin. the function of the track roller is to convey the weight of excavator to the ground. When excavator is run on uneven ground,track rollers carry a tremendous impact. Therefore,the support of track rollers is huge.Moreover,if it is of poor quality and is often dusty,it needs a very good sealing to prevent dirt,sand,and water from damaging it. With high quality hardness ware-resisting alloy chrom&molybdenum floating seal and elastic rubber O ring,deep hardnedd wear surface,good quality bronze bushings,steel shaft made by round steel or forging,well lubricated oil recycle system,our products are according to the standard of OEM to manufacture.     Bulldozer catalogue   KOMATSU/CAT/Bulldozers dozers parts BD2G S/F、BD2G D/F、D20 S/F、D20 D/F、D31 D/F-15/16、D31 S/F-17/18/20、D3C S/F、D3C D/F、D41A-6 S/F、D41A-6 D/F、D4 S/F、D4 D/F、D4D S/F、D4D D/F、D50 S/F、D50 D/F、D5 D/F、D5 S/F、D6D S/F、D6D D/F、D60 S/F、D60 D/F、D6H S/F、D6H D/F、D7 S/F、D7 D/F、D7G S/F、D7G D/F、D80-12 S/F、D80-12 D/F、D85-18 S/F、D85-18 D/F、D155-1 S/F、D155-1 D/F、D155-5 S/F、D155-5 D/F、D355 S/F、D355 D/F、D65EX-12 S/F、D65EX-12 D/F、D60/D65-8 S/F、D60/D65-8 D/F、D275A-5 S/F、D275A-5 D/F SHANTUI SD08、SD13、SD16、SD22、SD32、SD42、SD52