Track and Carrier Rollers are mounted to the bottom of the track frame, they carry the weight of the machine while it is traveling and digging. Roller friction and shock loads transmitted from the track chain create heat in the interior of rollers and on the roller surface, so they are expected to wear over time. At NBSJ, we take several steps to longer the wear life.
NBSJ offers a wide range of track rollers for the most popular machine models. All rollers are engineered with forged alloy steel which undergoes a proper heat treatment allowing durability for wear and impact. They are produced with cutting edge processes such as rotary friction welding robots and induction heat treatments to ensure proper hardness levels. Our rollers are highly praised in the market as a product with a long wear life, and impact resistance.
Roller body: We purchase 40MnB from high quality steel plant. After quenching, medium frequency induction hardening and tempering, reaching an ultimate surface hardness at 53-58HRC, and hardening depth at more than 4.5mm, which could be around 2mm deeper than a poorly heat-treated product.
Roller seals: Seals are with 3% of Mo (Molybdenum) , and a lifetime at 3000-5000 hours. Compared to seals that with 0.5% Mo or lower, our lifetime could be 2000-3000 hours longer.
Roller shafts: Highly polished to reduce friction to extend roller life, surface roughness is less than Ra 0.4, which is much higher than the common roughness Ra 0.8-1.6. Also, the bar goes through quenching, medium frequency induction hardening and tempering.
High standards: We buy high quality steel bars, then machine them to required sizes. For example, when the OEM shaft size is 65mm, we would not use bar with diameter at 60mm or even 58mm (both are existing sizes in the steel market), instead, we use 70mm diameter bar to machine it down to 65mm, to ensure the full OEM size and weight, also, to get rid of any possible defects on the surface of raw steel.
Our top and bottom track rollers are designed for excellent performance in the toughest environments for all types of dozers and crawlers. Our lines of lower track rollers and the upper carrier rollers are designed to hold up in the most challenging conditions. We have a wide range of aftermarket rollers to fit all common equipment models and makes from the top manufacturers: CATERPILLAR, CASE, DAEWOO-DOOSAN, FIAT-NEW HOLLAND, HITACHI, HYUNDAI, JCB, KOBELCO, KOMATSU, LIEBHERR, SAMSUNG-VOLVO, JOHN DEERE and more.