Round Key

The round key is a cylindrical-shaped pin-type key. It is also named pin key and Nordberg key. Sometimes it is tapered at the ratio of 1:50 for light-duty purposes and a ratio of 1:200 for heavy-duty purposes. The keyway is easily made by drilling partially in the shaft and hub. The shaft keyway and the hub keyway have a cylindrical gap to fit the key. One-half of the key is fitted on the shaft keyway and the remaining upper part is fitted on the hub keyway. The keyway is machined by partial drilling on the shaft and the hub. The diameter of the key is 1/6 times the shaft diameter. Round keys are used to transmit a high amount of torque. Shear concentration is less while torque transmission.