company news about Worried About Bucket Elevator Back-Running in Thai Rice Mills? Heavy-Duty One-Way Clutch Bearings Make Emergency Stops Safer

In Thai rice and grain processing plants, bucket elevators are used in almost every section—from raw grain intake and drying to finished rice storage. Many plant managers have experienced the same nightmare: when a power outage or drive failure occurs under full load, the elevator starts to run backward, and rice pours down from the top like a waterfall. This can deform buckets and casings, and even damage the gearbox and motor shaft.

Traditional solutions use small mechanical brakes or light-duty ratchet devices at the drive end. However, under frequent starts and stops and heavy dust from rice and husk, these devices often have limited service life and may fail to hold the elevator in critical conditions. For this kind of “high lift + heavy load + dusty environment”, we recommend using a roller-type one-way clutch bearing with an integral inner race on the drive shaft. The ASNU series supplied by our company under the Suma brand is a typical choice.

Models such as ASNU40 and ASNU50 are designed for approx. 40–50 mm shaft diameters. The inner race is fully machined and mates directly with the drive shaft, while the outer race is mounted in a dedicated housing. A full complement of rollers operates between the races, providing a large contact area and strong load capacity, ideal for absorbing the shock torque of a fully loaded bucket elevator during shutdown. Compared with a separate “bearing + ratchet” design, ASNU requires less axial space and fewer components; maintenance mainly involves checking lubrication and clearance.

Several Thai rice mills have adopted Suma ASNU40/50 on new or retrofitted drive sections and added controlled stop tests in their commissioning procedure. Even when the elevator is stopped under full load, the drive shaft is reliably locked by the one-way clutch, the bucket chain remains in place with only minor movement, and “run-back incidents” have largely disappeared. For local grain engineering companies, standardizing on ASNU heavy-duty clutches also helps highlight safety margins when bidding and presenting technical solutions, strengthening the competitiveness of their complete line designs.