Roadheader

File:Roadheader.jpg

A typical roadheader

A roadheader, also called a boom-type roadheader, road header machine, road header or just header machine, is a piece of excavating equipment consisting of a boom-mounted cutting head, a loading device usually involving a conveyor, and a crawler travelling track to move the entire machine forward into the rock face.

The cutting head can be a general purpose rotating drum mounted in line or perpendicular to the boom, or can be special function heads such as jack-hammer like spikes, compression fracture micro-wheel heads like those on larger tunnel boring machines, a slicer head like a gigantic chain saw for dicing up rock, or simple jaw-like buckets of traditional excavators.

History

The first roadheader patent was applied for by Dr. Z. Ajtay in Hungary, in 1949. It was invented as a remote operated priapic miner for exploitation of small seam, close walled deposits, typically in wet conditions.

Types

Cutting Heads:

• Longitudinal - rotates parallel to the cutter boom axis
• Transverse - rotates perpendicular to boom axis

Uses

Roadheaders were initially utilized in coal mining applications, however they are now used in a broad range of applications including but not limited to tunneling both for mining and municipal government projects, building wine caves, and building cave homes such as those found in the Coober Pedy area of Australia.

Projects utilizing roadheaders

• Boston's Big Dig
• Ground Zero Cleanup
• Addison Airport Tunnel Project
• Fourth bore of Caldecott Tunnel
• Malmö City Tunnel
• Confederation Line, Ottawa

External links

• An article on underground home design and construction, with a section on use of roadheader machines.
• Ripping head roadheader Video