DOSCO Miner
The “DOSCO Miner” was a made-in-Nova-Scotia continuous mining machine that helped mechanize coal mining in the 1950s and laid the groundwork for how modern coal mining is still done.
Most of the technology and methods used in Nova Scotia’s historical coal mines came from Britain. This began in 1827 when the General Mining Association sailed from England to Pictou harbour on a ship called the Margaret Pilkington, carrying 200 tons of mining equipment, skilled engineers and experienced miners. The GMA, which had a monopoly on most Nova Scotian minerals until 1857, brought the Industrial Revolution to Nova Scotia with new technologies like steam engines and railways. It also professionalized coal mining here, helping make coal one of the province’s most important industries for generations.
Coal mining in Nova Scotia largely copied British practices for more than a century but as the 1900s wore on, the influence of the United States became more dominant, particularly as it became apparent after World War Two that Nova Scotia’s coal mines needed to mechanize to compete with American mines.
In the late 1940s, continuous mining machines were developed that carved coal from the working face of a mine with a rotating drum studded with picks, and deposited the coal onto conveyor belts that carried it out of the area being mined. Miners operated the machines but no longer did the physical work of extracting it.
Nova Scotia’s Dominion Steel and Coal Company (DOSCO) developed its own continuous mining machine, the DOSCO Miner, and had it built at the Trenton steel works, which DOSCO owned, making it a uniquely Nova Scotian invention.
In 1949, the DOSCO Miner was tested at the Little Pond coal mine in Sydney Mines and at the McBean Mine in Thorburn, Pictou County. The machines generally worked well and the testing led to further improvements. Roof (mine ceiling) conditions in the Pictou coalfield prevented them being used there for safety reasons but their use in Cape Breton grew quickly.
The 1950 Nova Scotia Department of Mines’ annual report said, “Last year the DOSCO Miner was placed in operation in Dominion No. 18 Colliery [New Victoria]. It is from this ‘pilot’ machine that the design for five new ones is being drawn. These new machines will have a number of improvements over the original type.”
The 1951 annual report said, “Preparations are being made to install a Dosco Continuous Miner at No. 12, No. 1-B and No. 4 Collieries.”
In 1952, five Miners were in operation and in 1953, 10 were being used.
The 1953 annual report described the Miners as an electrically-driven, hydraulically-operated machine, 16 feet 9 ¾ inches long, 4 ½ feet wide and 3 feet 0 ¾ inches high, weighing 19.9 tons. They consisted principally of a caterpillar-driven frame and a 57-inches-wide, multi-chain cutting head. DOSCO Miners had three water-cooled electric motors to power the hydraulic pumps and the caterpillar driving engines that moved the Miner.
A DOSCO Miner’s cutting head was pushed into the solid coal and picks on the cutting head dug out and pulled the coal back to a conveyor belt system that carried the coal to where it was loaded into tubs or cars. The cutting head started close to floor-level and was lifted toward the roof to extract coal. After this, the cutting head was retracted, the cycle complete.
This took less than half a minute. The machine then moved forward and started a new cycle, quickly extracting large amounts of coal.
To ensure continuity, the DOSCO Miner had a crew of seven men. There were two operators who relieved each other, three timbermen who installed wooden supports to help hold up the roof, one mechanic and one company official.
The 1953 annual report said, “The Dosco Miner was designed, engineered and produced to mine and load 500 tons in an 8-hour shift. Today, the best output produced in 8 hours by one machine has been 587 tons; the best weekly output to date has been 2,842 tons, and the peak production rate recorded has been 1 ton in 6 seconds.”
According to the 1954 annual report, “The increase in coal production and the new total output records established during the past year in the Glace Bay-New Waterford district can be attributed almost entirely to the continued and more extensive of the Dosco Continuous Miner.”
There were 14 of the machines operating in the district that year and plans were being made to install Miners in the No. 4 and the Princess mines: “It is expected that somewhere in the vicinity of six or seven of these machines will be operating between these two mines by the close of the coming years.”
The DOSCO Miner would be used underground in all of the company’s mines, but production of the Miner ceased when A. V. Roe (Hawker Siddley) took control of DOSCO in 1957 and stopped producing them at Trenton. The DOSCO Miner’s maintenance issues - it had over 1600 separate parts - and operational limitations led to it being phased out in the 1960s and replaced by other machines.
Continuous miner machines, which are still widely used today in coal mines like Cape Breton’s Donkin mine, improve safety because miners are not directly exposed to active working areas.
Nova Scotian innovations related to continuous miners did not end with the DOSCO Miner. Pioneer Coal from Antigonish started operating a surface mine at Coalburn in 1999. The company tested its NovaMiner 2000 at the mine, a continuous mining machine that Pioneer built and patented specifically for Pictou County’s unusually steeply-dipping coal seams (i.e. the Foord seam dips, or angles downward, at 26 degrees). Prior to the NovaMiner 2000, continuous miners were limited to working a 15-degree angle.
The NovaMiner 2000 can mine coal up to one thousand feet underground by cutting tunnels into the side of a surface mine while a series of conveyor belts carry the coal out of the tunnel. This reduces environmental impacts by making it unnecessary to remove overburden (the rock, dirt and vegetation above the coal).
The NovaMiner was later used at the Point Aconi surface coal mine.
Pioneer Coal reclaimed the Coalburn and Point Aconi mines and both are beautiful green spaces today.
