Double sprocket with hub, pitch 1/2", 21 teeth

MR Piñón doble 1/2" Z21 belongs to sprockets and gears, part of our Power transmission range. Tell us how many you need by WhatsApp or email and we'll get back to you promptly with a quote for Piñón doble 1/2" Z21 and any equivalents.

The MR-PINON-DOBLE-1-2-Z21 is a double sprocket from MR, made of SAE 1045 steel. It has a 1/2" pitch and 21 teeth per chain ring, with two chain rings on a central hub. This design lets one shaft drive two chains of the same pitch, which is useful when space is tight and two mechanisms need to run in parallel, such as in conveyors, elevators or agricultural equipment.

The part number MR-PINON-DOBLE-1-2-Z21 identifies a double sprocket with hub, 1/2" pitch and 21 teeth (z=21), machined from SAE 1045 steel. The term "double" means two chain rings are integrated into one hub, so a single shaft can transmit motion to two chains of the same pitch. SAE 1045 is a medium-carbon steel that can be machined and then heat treated if the application requires it. The hub simplifies mounting and securing on the shaft, with options for a keyway or set screws as needed.

You will find this type of double sprocket in chain drives that need to synchronize or split motion between two branches. Common examples include belt or roller conveyors, bucket elevators, farm machinery, packaging equipment and production lines with two parallel chains. It also works as an idler or drive wheel in compact mechanisms, where one part handles two transmissions and reduces shaft complexity.

When selecting and installing this sprocket, check the chain pitch, number of teeth, shaft diameter and mounting method. The 1/2" pitch must match the chain you plan to use; the 21 teeth set the drive ratio along with the driven sprocket. Make sure both chain rings align with their chains and that the shafts are parallel. The hub should sit properly on the shaft and be secured without axial movement. For equipment with varying loads, inspect lubrication and tension on each chain branch separately.

If you need a sprocket with a different tooth count, another pitch or a modified hub, a custom option can be reviewed. To request an equivalent, send the part number MR-PINON-DOBLE-1-2-Z21 or the original sprocket details: pitch, number of teeth, shaft diameter, mounting type and number of chain rings. With that information, the team compares it against the alternatives supplied by MR and identifies the most suitable choice.

MR Industrial Accessories LLC supplies this double sprocket in SAE 1045 steel along with chains, pulleys and other power transmission components. To request a quote or ask about a variant, send the part number on WhatsApp or by email. The team responds promptly and can suggest equivalents and help you choose.