Key features of a core drilling rig drill core barrel include: 1. **Material**: Usually made from high-strength steel to resist wear and tear. 2. **Length**: Varies depending on the depth of the borehole and the type of material being sampled. 3. **Inner Diameter**: Matches the size of the core samples that will be collected. 4. **Connection Type**: Designed to connect with other parts of the drilling assembly, often using threaded connections. 5. **Lubrication System**: Some barrels have internal systems for lubricating the drill bit and reducing friction. The Core drill rig drill core barrel is an essential part of the drilling process because it allows for the collection of intact samples that can provide valuable information about the subsurface geology, which is crucial for mineral exploration, environmental studies, and engineering project.