Freewheels and backstops

A freewheel is a one-way clutch. It carries torque while the shaft turns one way and lets go when it turns the other. How you install it decides which of three jobs it does. As a backstop, it keeps an inclined conveyor, an elevator or a pump from running backward after shutdown. As an overrunning clutch, it lets a driven part spin faster than whatever drives it. As an indexing clutch, it turns back-and-forth motion into step-by-step advance, as in feeders.

Series naming differs from one maker to another. TSUBAKI lists sizes such as B 203, B 205 and B 209, as well as 1 M. At INA, HF0306-KF and HF0612-KF are roller freewheels, and HF0306-KF-R is a variant in the same size. The suffix changes the design, so ask for the complete part number.

Size it from the torque it has to transmit or hold, with margin for starts and shock loads, and from the shaft diameter. Next, check maximum overrunning speed, whether the unit has its own bearings to center it or sits between the machine's bearings, how it fastens to shaft or hub, and how it is lubricated. Finally, set the locking direction, viewing the shaft from each end.

We quote TSUBAKI and INA freewheels. Send the full part number on WhatsApp or, for a replacement, the shaft diameter, direction of rotation, torque and a photo of the unit, and we'll get your quote back shortly.