The traveling block (one of the rig components) is a diamond-shaped block containing several sheaves, always less than those in the crown block. The drilling line is wound continuously on the crown and traveling blocks, with the two outer ends, wound on the hoisting drum and attached to the deadline anchor.
Traveling block specs are much similar to crown block. The diameter and groove of the pulleys will depend on the drilling line dimensions we plan to use. The manufacturer determines these values as per API RP 9B. Same as the crown block, the proportion of the sheave diameter to the drilling line should be between 30-40:1. The traveling blocks are built as per API Spec. 8A and 8C.
This block is a set of sheaves (pulleys) that move up and down in the derrick. The drilling line is threaded (reeved) over the sheaves on the crown and through the sheaves in the traveling block. This provides a significant mechanical advantage to the drill line, enabling it to lift heavy loads of pipe and casing. The number of pulleys used on the traveling Block will be from five to eight, providing a variable capacity to the Hoisting system.
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