Community hub
Recent from talks
Contribute something to knowledge base
Content stats: 0 posts, 0 articles, 1 media, 0 notes
Members stats: 0 subscribers, 0 contributors, 0 moderators, 0 supporters
Subscribers
Supporters
Contributors
Moderators
Hub AI
Union Pacific GTELs AI simulator
(@Union Pacific GTELs_simulator)
Hub AI
Union Pacific GTELs AI simulator
(@Union Pacific GTELs_simulator)
Union Pacific GTELs
The Union Pacific GTELs were a series of gas-turbine–electric locomotives built by Alco-GE and General Electric from 1952 to 1961 and operated by Union Pacific from 1952 to 1970.
Union Pacific operated the largest fleet of gas-turbine–electric locomotives (GTELs) of any railroad in the world. The prototype, UP 50, was the first in a series built by General Electric for Union Pacific's long-haul cargo services and marketed by the Alco-GE partnership until 1953. The prototype was introduced in 1948 and was followed by three series of production locomotives. At one point, Union Pacific said the GTELs hauled more than 10% of the railroad's freight.[citation needed]
Fuel economy was poor, for the turbine consumed roughly twice as much fuel as an equally powerful diesel engine. This was initially not a problem, because Union Pacific's turbines burned Bunker C heavy fuel oil that was less expensive than diesel. But this highly viscous fuel is difficult to handle, with a room-temperature consistency similar to tar or molasses. To solve this problem, a heater was built into the fuel tanks (and later into fuel tenders) to heat the fuel to 200 °F (93 °C) before feeding it into the turbine. Eventually UP switched from Bunker C to modified No. 6 heavy fuel oil, which contained less pollutants and solvents.[citation needed] Soot buildup and blade erosion caused by corrosive ash plagued all of the turbines. Changes to the air intake systems on the production turbine locomotives improved the quality of the air that reached the turbines, which in turn reduced the wear to the turbine blades and increased the turbine's running life. The GTELs were operated into late 1969 and the final two (numbers 18 and 26) were stored at the Cheyenne roundhouse in operating condition until being retired in February 1970. Both were later sent to museums.
Union Pacific had long sought the biggest and best locomotives. In the 1930s, a pair of steam-turbine locomotives were tried but rejected. Before World War II, Union Pacific had been adding diesels to its roster, but none pulled road freight trains. The idea of using four diesels to equal the power of a steam locomotive was unappealing, so the search began for something bigger. General Electric had been building gas turbines for aircraft and proposed using something similar on a locomotive. Union Pacific thought maintenance costs for a locomotive were largely independent of its power, so a smaller number of more powerful locomotives would save money.
Union Pacific decided the best way for the turbine locomotives to realize their potential would be to put them on mainline freight trains. The long runs and relatively high speeds would maximize the turbines' efficiency.
After Union Pacific expressed interest, GE built a prototype, GE 101, completed in November 1948. After tests in the Northeast during June 1949, it was renumbered UP 50. Painted in Union Pacific Armour Yellow, UP 50 began a round of tests. Union Pacific never took ownership of this locomotive. This was one of the few internal combustion locomotives in North America that had a cab at each end. The cabs themselves resembled the FA units being built by Alco-GE at that time. The sides of the locomotive had numerous air intake louvers that could be opened and closed in varying patterns.
UP 50 was a cab unit with a B+B-B+B wheel arrangement – four two-axle trucks, with pairs connected by span bolsters. The turbine produced 4,800 hp (3.6 MW), of which 4,500 hp (3.4 MW) was available for traction. This power output was more than double that of diesel–electric units of that era.
For starting, the unit's auxiliary diesel generator would power a set of windings in the gas turbine's main generator, causing the generator to rotate. The generator's rotation would begin to spin up the turbine, at which point diesel fuel would be used to start combustion. A steam generator would heat and liquefy the turbine's primary fuel supply (heavy Bunker C oil). When the turbine and fuel oil reached their minimum operating temperatures, the fuel to the turbine would be switched from diesel to the primary fuel.
Union Pacific GTELs
The Union Pacific GTELs were a series of gas-turbine–electric locomotives built by Alco-GE and General Electric from 1952 to 1961 and operated by Union Pacific from 1952 to 1970.
Union Pacific operated the largest fleet of gas-turbine–electric locomotives (GTELs) of any railroad in the world. The prototype, UP 50, was the first in a series built by General Electric for Union Pacific's long-haul cargo services and marketed by the Alco-GE partnership until 1953. The prototype was introduced in 1948 and was followed by three series of production locomotives. At one point, Union Pacific said the GTELs hauled more than 10% of the railroad's freight.[citation needed]
Fuel economy was poor, for the turbine consumed roughly twice as much fuel as an equally powerful diesel engine. This was initially not a problem, because Union Pacific's turbines burned Bunker C heavy fuel oil that was less expensive than diesel. But this highly viscous fuel is difficult to handle, with a room-temperature consistency similar to tar or molasses. To solve this problem, a heater was built into the fuel tanks (and later into fuel tenders) to heat the fuel to 200 °F (93 °C) before feeding it into the turbine. Eventually UP switched from Bunker C to modified No. 6 heavy fuel oil, which contained less pollutants and solvents.[citation needed] Soot buildup and blade erosion caused by corrosive ash plagued all of the turbines. Changes to the air intake systems on the production turbine locomotives improved the quality of the air that reached the turbines, which in turn reduced the wear to the turbine blades and increased the turbine's running life. The GTELs were operated into late 1969 and the final two (numbers 18 and 26) were stored at the Cheyenne roundhouse in operating condition until being retired in February 1970. Both were later sent to museums.
Union Pacific had long sought the biggest and best locomotives. In the 1930s, a pair of steam-turbine locomotives were tried but rejected. Before World War II, Union Pacific had been adding diesels to its roster, but none pulled road freight trains. The idea of using four diesels to equal the power of a steam locomotive was unappealing, so the search began for something bigger. General Electric had been building gas turbines for aircraft and proposed using something similar on a locomotive. Union Pacific thought maintenance costs for a locomotive were largely independent of its power, so a smaller number of more powerful locomotives would save money.
Union Pacific decided the best way for the turbine locomotives to realize their potential would be to put them on mainline freight trains. The long runs and relatively high speeds would maximize the turbines' efficiency.
After Union Pacific expressed interest, GE built a prototype, GE 101, completed in November 1948. After tests in the Northeast during June 1949, it was renumbered UP 50. Painted in Union Pacific Armour Yellow, UP 50 began a round of tests. Union Pacific never took ownership of this locomotive. This was one of the few internal combustion locomotives in North America that had a cab at each end. The cabs themselves resembled the FA units being built by Alco-GE at that time. The sides of the locomotive had numerous air intake louvers that could be opened and closed in varying patterns.
UP 50 was a cab unit with a B+B-B+B wheel arrangement – four two-axle trucks, with pairs connected by span bolsters. The turbine produced 4,800 hp (3.6 MW), of which 4,500 hp (3.4 MW) was available for traction. This power output was more than double that of diesel–electric units of that era.
For starting, the unit's auxiliary diesel generator would power a set of windings in the gas turbine's main generator, causing the generator to rotate. The generator's rotation would begin to spin up the turbine, at which point diesel fuel would be used to start combustion. A steam generator would heat and liquefy the turbine's primary fuel supply (heavy Bunker C oil). When the turbine and fuel oil reached their minimum operating temperatures, the fuel to the turbine would be switched from diesel to the primary fuel.
Recent media
Recent media