Travelling block

Drilling Equipment & Components

The traveling block is the moving pulley assembly that travels up and down the derrick, suspended by the drilling line from the crown block. It supports the top drive (or hook/swivel) and essentially carries the entire weight of the drillstring.

It is a massive piece of equipment, often weighing several tons itself to ensure it falls fast enough when unwinding the drum. It contains sheaves matching the crown block and runs on guide rails in the derrick to prevent it from swinging during operations, especially on floating offshore rigs.