Drilling jumbo

A Drilling jumbo or drill jumbo is a rock drilling machine.

Use
Drilling jumbos are usually used in underground mining, if mining is done by drilling and blasting. They are also used in tunnelling, if rock hardness prevents use of tunnelling machines. It is considered as a powerful tool to facilitate labor-intensive process for mineral extraction.

Description
A drilling jumbo consists of one, two or three rock drill carriages, sometimes a platform, which the miner stands on to load the holes with explosives, clear the face of the tunnel or do something else. The carriages are bolted onto the chassis, which supports the miner's cabin as well as the engine. Although modern drilling jumbos are relatively large, there are smaller ones for use in cramped conditions. Whereas modern jumbos are usually fitted with rubber tires and diesel-powered, there are also exist variants with steel wheels, to ride on rails and even single carriage sled-mounted ones. Electric power is also common, and historic jumbos were powered by compressed air. Electricity and compressed air produce little to no exhaust gases, which is preferable if work is done in smaller tunnels where good ventilation is difficult. The drilling jumbo was invented in 1849 by J.J Couch of Philadelphia.