The tram (or
dram) cars used for mine haulage are generally called
tubs. The term
mine car is commonly used in the United States
Humans Mine workers have often been used to push mine carts. In the very cramped conditions of hand-hewn mining tunnels, children were also often used before the advent of child labour legislation, either pushing the carts themselves or tending to animals that did (see below).
Pit ponies . Before locomotives, slate trains would travel down to
Porthmadog under gravity, and be pulled back up by horses The Romans were the first to realise the benefits of using animals in their industrial workings, using specially bred
pit ponies to power supplementary work such as mine pumps. Ponies began to be used underground, often replacing
child or female labour, as distances from
pit head to
coal face became greater. The first known recorded use in Britain was in the
County Durham coalfield in 1750; in the United States,
mules were the dominant source of animal power in the mine industry, with horses and ponies used to a lesser extent. At the peak in 1913, there were 70,000 ponies underground in Britain. In later years, mechanical haulage was quickly introduced on the main underground roads replacing the pony hauls and ponies tended to be confined to the shorter runs from coal face to main road (known in
North East England as "putting", in the United States as "tramming" or "gathering") which were more difficult to mechanise. As of 1984, 55 ponies were still at use with the
National Coal Board in Britain, chiefly at the modern pit in
Ellington, Northumberland.
Dandy wagons were often attached to trains of full drams, to contain a horse or pony. Mining and later railway engineers designed their
tramways so that full (heavy) trains would use gravity down the slope, while horses would be used to pull the empty drams back to the workings. The Dandy wagon allowed for easy transportation of the required horse each time. Probably the last colliery horse to work underground in a British coal mine,
Robbie, was retired from Pant y Gasseg, near
Pontypool, in May 1999.
Cable haulage In the 19th century after the mid-1840s, when the German invention of
wire rope became available from manufactories in both Europe and North America, large
stationary steam engines on the surface with
cables reaching underground were commonly used for mine haulage. Unsurprisingly, the innovation-minded managers of the
Lehigh Coal & Navigation Company pioneered the technology in America using it to allow the dead-lift of loaded coal consists up the
Ashley Planes, and the augmentation of their works in and above the
Panther Creek Valley with new gravity switchback sections and return cable inclines, but most notably by installing two cable lift sections and expanding the already famous
Mauch Chunk Switchback Railway with a 'back track' dropping car return time from 3–4 hours to about 20 minutes, which the new inclines then fed from new mine shafts and
coal breakers farther down into the valley. Sometimes, stationary engines were even located underground, with the boiler on the surface, though that was a minority situation. All of the cable haulage methods were primarily used on the main haulage ways of the mine. Typically, manual labor,
mules or
pit ponies were used in gathering filled cars from the working areas (galleries were driven across seams as much as possible) to main haulage ways. In the first decade of the 20th century, electric locomotives were displacing animal power for this secondary haulage role in mines where sparking triggered explosive methane buildup was a lesser danger. Several cable haulage systems were used: In
slope mines, where there was a continuous downgrade from the entrance to the working face, the rope from the
hoisting engine could be used to lower empty cars into the mine and then raise full cars. In
shaft mines, secondary hoisting engines could be used to pull cars on grades within the mine. For
grades of a few percent, trains of 25 cars each carrying roughly half a ton were typical in the 1880s. In mines where grades were not uniform or where the grades were not steep enough for gravity to pull a train into the mine, the main hoisting rope could be augmented with a tail rope connected to the opposite end of the train of mine cars. The tail-rope system had its origins on cable-hauled surface inclines prior to the 1830s. This was the dominant system in the 1880s Frequently, one engine was used to work both ropes, with the tail rope reaching into the mine, around a pulley at the far end, and then out again. Finally, the most advanced systems involved continuous loops of rope operated like a
cable car system. Some mines used endless chains before wire-rope became widely available. The endless chain system originated in the mines near
Burnley (England) around 1845. An endless rope system was developed in
Nottinghamshire around 1864, and another independently developed near
Wigan somewhat later (also in England). In these systems, individual cars or trains within the mine could be connected to the cable by a grip comparable to the grips used on surface cable car systems. In some mines, the haulage chain or cable went over the top of the cars, and cars were released automatically when the chain or cable was lifted away by an overhead pulley. Where the cable ran under the cars, a handheld grip could be used, where the grip operator would ride on the front car of the train working the grip chained to the front of the car. In some cases, a separate grip car was coupled to the head of the train. At the dawn of the 20th century, endless rope haulage was the dominant haulage technology for the main haulage ways of underground mines.
Porter, Bell & Co. appears to have built the first underground mining locomotives used in the United States around 1870. By 1874, the
Consolidation Coal Company and
Georges Creek Coal and Iron Company were using several Porter locomotives in their underground mines in the
Georges Creek Valley of
Maryland. Other users included several coal mines near
Pittsburgh, Pennsylvania, the
Lehigh Coal and Navigation Company and an iron mine in the
Lake Superior Iron Ranges. Porter's mine locomotives required a minimum 5-foot clearance and 4-foot width when operating on 3-foot gauge track, where they could handle a 20-foot radius curve. The
Baldwin Locomotive Works built similar locomotives, starting in 1870. By the early 20th century, very small British-made oil-fired steam locomotives were in use in some South African mines. Porter and
Vulcan (Wilkes-Barre) advertised steam mine locomotives in 1909 and 1911. By the early 1920s, only a few small mines in the
Pocahontas Coalfield in
West Virginia were using steam locomotives underground. Nonetheless, both
Baldwin and
Vulcan continued to advertise steam locomotives for underground use outside the coal industry as late as 1921.
Compressed air locomotives Compressed-air locomotives were powered by
compressed air carried on the locomotive in compressed-air containers. This method of propulsion had the advantage of being safe but the disadvantage of high operating costs due to very limited range before it was necessary to recharge the air tanks. Generally, compressors on the surface were connected by plumbing to recharge stations located throughout the mine. Recharging was generally very fast. Narrow gauge compressed air locomotives were manufactured for mines in Germany as early as 1875, with tanks pressurized to 4 or 5
bar. The
Baldwin Locomotive Works delivered their first compressed air locomotive in 1877, and by 1904, they offered a variety of models, most with an
0-4-0 wheel arrangement. Compressed air locomotives were introduced in the
Newbottle Collieries in
Scotland in 1878, operating at 200
psi (14
bar). Ordinary mine compressed-air systems operating at 100 psi (7 bar) only allowed a few hundred feet of travel. By the late 1880s,
Porter was building locomotives designed for 500 to 600
psi (34-41
bar). By the early 1900s, locomotive air tank pressures had increased to from 600 to 800 psi (41-55 bar), although pressures up to 2000 psi (140 bar) were already envisioned. The
Homestake in South Dakota, USA used such high pressures, with special compressors and distribution piping. Except for very small prospects and remote small mines, battery or diesel locomotives have replaced compressed air.
Overhead-electric locomotives 1894 The
electric motor technology used pre-1900 to
DC with a few hundred volts and a direct supply of power to the motor from the overhead wire enabled the use of efficient, small and sturdy tractors of simple construction. Initially, there was no voltage standard, but by 1914, 250 volts was the standard voltage for underground work in the United States. This relatively low voltage was adopted for safety's sake. The first electric mine railway in the world was developed by
Siemens & Halske for
bituminous coal mining in Saxon
Zauckerode near Dresden (now Freital) and was being worked as early as 1882 on the 5th main cross-passage of the Oppel Shaft run by the Royal Saxon Coal Works. In 1894, the mine railway of the Aachen smelting company,
Rothe Erde, was electrically driven, as were subsequently numerous other mine railways in the
Rhineland,
Saarland Lorraine,
Luxembourg and Belgian
Wallonia. There were large scale deliveries of electric locomotives for these railways from
AEG,
Siemens & Halske,
Siemens-Schuckert Works (SSW) and the Union Electricitäts-Gesellschaft (UEG) in these countries. The first electric mine locomotive in the United States went into service in mid 1887 in the Lykens Valley Coal Company mine in
Lykens, Pennsylvania. The 35 hp motor for this locomotive was built by the Union Electric Company of
Philadelphia. The 15000 pound (6800 kg) locomotive was named the Pioneer, and by mid 1888, a second electric locomotive was in service at that mine. Use in the
Appalachian coal fields spread rapidly. By 1903, there were over 600 electric mine locomotives in use in America with new ones being produced at a rate of 100 per year. Initially, electric locomotives were used only where it was economical to string
overhead line for power. This limited their usage for gathering loads at the mine face, where trackage was temporary and frequently relocated. This motivated the development of battery locomotives, but in the first decade of the 20th century the first successful electric gathering locomotives used cable
reels. To run on tracks away from overhead lines, the
power cable was clipped to the overhead line and then automatically unreeled as the locomotive advanced and reeled up as the locomotive returned. Crab locomotives were equipped with a
winch for pulling cars out of the un-powered tracks. This approach allowed use of temporary track that was too light to carry the weight of the a cable-reel or battery locomotive. The disadvantage of a crab locomotive was that someone had to pull the haulage cable from the winch to the working face, threading it over
pulleys at any sharp turns. Explosion-proof mining locomotives from
Schalker Eisenhütte are used in all the mines owned by
Ruhrkohle (today
Deutsche Steinkohle).
Internal-combustion locomotives mine railway locomotive. The
Gasmotorenfabrik Deutz (Deutz Gas Engine Company), now
Deutz AG, introduced a single-cylinder benzine locomotive for use in mines in 1897. Their first mining locomotives were rated at and weighed . The original engine was long, wide and high and weighed . Typical Deutz mine engines in 1906 were rated at . By this time, double-cylinder . engines built by
Wolseley Motors were being used in South African mines. By 1914,
Whitcomb Locomotive Works,
Vulcan Iron Works, and Milwaukee Locomotive Manufacturing Co. (later merged with Whitcomb) were making gasoline mining locomotives in the United States with 4 and 6
cylinder engines. Late 19th and early 20th century mine railway locomotives were operated with
petrol benzene and
alcohol / benzene mixtures. Although such engines were initially used in metal mines, they were in routine use in coal mines by 1910.
Firedamp safety was achieved by wire gauze shields over intake and exhaust ports as well as cooling water injection in the exhaust system. Bubbling the exhaust through a water bath also greatly reduced noxious fumes. For safety (noxious fumes as well as flammability of the fuel) modern mine railway internal combustion locomotives are only operated using diesel fuel. Catalytic scrubbers reduce carbon monoxide. Other locomotives are electric, either battery or trolley.
Battery-electric locomotives chromite mine in
Stillwater County, Montana Battery powered locomotives and systems solved many of the potential problems that combustion engines present, especially regarding fumes, ventilation and heat generation. Compared to simple electric locomotives, battery locomotives do not need trolley wire strung over each track. However, batteries are heavy items which used to require long periods of charge to produce relatively short periods of full-power operation, resulting in either restricted operations or the need for the doubling-up of equipment purchasing. In the 19th century, there was considerable speculation about the potential use of battery locomotives in mines. By 1899,
Baldwin-Westinghouse had delivered an experimental battery locomotive to a Virginia mine; battery recharging occurred whenever the locomotive was running under
trolley wire, while it could run from battery when working on temporary trackage near the
face. This locomotive was eventually successful, but only after the voltage on the trolley system was stabilized. A
Siemens and Haske pure storage battery locomotive was in use in a coal mine in
Gelsenkirchen (Germany) by 1904. One problem with battery locomotives was battery replacement. This was simplified by use of removable battery boxes. Eventually, battery boxes were developed that included wheels so that they could be rolled off of the locomotive. While the initial motivation had to do with battery maintenance, the primary use for this idea was at charging stations where a discharged battery box could be rolled off and replaced with a freshly charged box. While popular, battery systems were often practically restricted to mines where systems were short, and moving relatively low-density ore which could explode easily. Today, heavy-duty batteries provide full-shift (8 hours) operations with one or more spare batteries charging. ==In operation==