Shaft Sinking In Mining Methods And Factors Affecting | Indian Minerology

SHAFT SINKING

Shaft sinking in mining is the process of developing a vertical or near-vertical big hole (Shaft) for any purpose, where there is no initial access to that part. It is a very dangerous, hard, and time-consuming process.

Mining, the age-old practice of extracting valuable resources from the Earth’s crust, has evolved over centuries into a sophisticated and technologically advanced industry. One of the most crucial processes in underground mining is shaft sinking. This intricate and challenging endeavor involves creating vertical tunnels that provide access to deeper layers of the Earth, facilitating the extraction of minerals, ores, and other precious substances. In this blog post, we’ll delve into the fascinating world of shaft sinking, exploring its methods, challenges, and significance in modern mining operations.

A historic mine shaft headframe – the iconic surface structure for hoisting

Uses of Shafts

Shafts can be used for many purposes. The main uses include:

For mining purposes
For underground temporary storage
For the foundation of bridges
For ventilation in any part of the earth

But here in this blog, we are going to discuss only its mining purpose.

Shaft Sinking Methods/Procedure

Technical diagram showing details of a steel shaft set and support structure

In the conventional method, sinking is done by traditional techniques. However, in places with special conditions (e.g., presence of water in the ground), special shaft sinking methods are required.

Shaft sinking is a very costly operation requiring a large initial capital investment. It is also slow and risky, demanding proper planning and skilled manpower.

Shafts can be developed in many shapes, but in mining, circular shafts are mainly preferred for safety and stability concerns.

Workers operating in a shaft sinking face with mechanized equipment

THE BASICS OF SHAFT SINKING IN MINING

At its core, shaft sinking is the process of excavating a vertical or near-vertical tunnel, known as a shaft, from the surface to reach valuable deposits located at depth. This tunnel serves as a conduit for miners, equipment, and materials, and also facilitates ventilation, communication, and transportation within the mine.

The process is multifaceted and involves several critical steps:

Site Selection and Planning: Thorough geological surveys and engineering assessments to determine location, angle, rock conditions, water table, and hazards.
Pre-sinking Preparations: Clearing area, building headframes, hoisting systems, and safety measures.
Drilling and Blasting: Boreholes drilled, explosives placed for controlled blasts to fracture rock.
Rock Removal: Muck removed using buckets, skips, or conveyors; supports (bolts, mesh) installed.
Lining the Shaft: Walls lined with concrete or steel to prevent collapse and ensure long-term stability.
Installation of Services: Ventilation, electricity, communication, and hoisting systems added.

Modern shaft sinking in progress – excavator removing muck at the bottom

Remote shaft liner monitoring and concrete spraying in progress

View inside a freshly lined concrete shaft during construction

SIGNIFICANCE OF SHAFT SINKING

The significance of shaft sinking in mining engineering cannot be overstated. It serves as the backbone of underground mining operations, providing vital access to deep resources, unlocking reserves, extending mine life, and enabling safe transport, ventilation, and operations.

Factors Influencing Shaft Sinking

Key factors include depth, material handled, manpower, machinery, mechanization level, ventilation needs, capital cost, operating expenses, and mineral value.

CONCLUSION

Shaft sinking is a remarkable engineering achievement that continues to evolve from manual methods to advanced mechanized techniques, enabling deeper, safer, and more sustainable mining for the future.