RUSSIA has the world's largest natural gas reserves, but despite various experiments over the years liquefied natural gas (LNG) has never become a favoured fuel source for locomotives.

However, with the emergence of new traction solutions that could be about to change. Late last year trials began with what is claimed to be the world's first gas-reciprocating locomotive, the TEM19, on the Golutvin - Karasevo line near Ozersk south of Yekaterinburg.

Since then the six-axle locomotive has completed more than 300 hours of trial running. So far the primary and secondary circuits have been checked, the locomotive weight has been balanced, and the algorithms for gas feeding to the engine have been calibrated. The plan is to complete the full range of tests by the end of 2014, after which production of the development batch will commence.

The TEM19 was developed by the Russian Institute of Research, Design and Technological Studies (VNIKTI) and Transmashholding (TMH) subsidiary Bryansk Machine Building Plant (BMZ) as part of Russian Railways' (RZD) energy strategy, which is seeking alternatives to diesel power for non-electrified lines. The use of natural gas power has the potential to reduce operating and life-cycle costs as well as making rail transport more environmentally-friendly.

The gas­piston locomotive is based on a modular design consisting of the following elements:

• driver's cab

• cryogenic unit with gas preparation and LNG feeder systems

• motor­generator set

• cooling system

• equipment chamber

• electrodynamic brake equipment module, and

• compressor unit.

A separate module contains secondary equipment deployed under the locomotive frame.

The modular design has simplified locomotive maintenance and repairs significantly.

Cryogenic fuel is stored in a removable tank positioned at the front of the locomotive, and the propulsion unit consists of a GDG800T motor­generator fired by LNG. Traction and secondary synchronous generators are mounted on the same frame as the gas­fired engine, which is cooled using antifreeze.

TEM19The cryogenic unit module consists of a cryogenic tank fitted with gas distribution and refilling systems; a quick­closing Norgren valve with an electric drive; a gas pressure regulator; a product evaporator; and a gas receiver, while the gas distribution system consists of a stainless steel pipeline together with shutoff and safety valves.

Mountings from a standard 20ft container are used on the cryogenic LNG storage tank. This is effectively a cartridge system because it is allows rapid removal and replacement of empty tanks, which can be transported to and from the depot on standard flat wagons.

The ac/dc electric transmission is based on a synchronous traction generator, a traction rectifier, and dc traction motors.

The TEM19 is equipped with a multifunctional microprocessor control, monitoring, and diagnostic system which controls and monitors the propulsion unit, ensuring optimum performance of the engine, generator, and traction electric motors in both traction and idle modes. It also provides programme ­level control of engine startup and shutdown and its rotational frequency. All the relevant information is displayed on the control panel screen. Radial cooling fans of the traction motors, traction and secondary rectifiers are fitted with asynchronous drives.

The compressor unit comprises an AKRV 3.2/10­1000 screw­type brake compressor with asynchronous electric traction and a compressed air drying and cleaning system.

The locomotive has an integrated safety system consisting of an ALSNV­1D cab signalling system with a KPD­ZPV onboard device for monitoring trip parameters, and a TSKBM telematic system for monitoring driver behaviour.

The driver's cab module is based on the cab of the TEM18DM locomotive, which has been certified and tested in operation.

The gas fired locomotive is also equipped with an automatic fire and gas detection system and conforms to all relevant Russian health regulations and standards governing signalling and communication equipment, occupational safety, fire prevention, environmental performance, and operating and maintenance requirements.

Advantages

LNG offers important environmental advantages over diesel locomotives because it produces fewer pollutants and the TEM19 also offers a 24% reduction in energy costs compared with a diesel locomotive of similar output. The engine takes less time to warm up in cold conditions because antifreeze is used as a coolant.

The use of easily-accessible and removable cylinder tanks reduces the time it takes to fit out the locomotive, cuts infrastructure costs, and enhances safety in operation and maintenance.

The TEM19 was recognised with an innovation award in the locomotives and rolling stock category at the Expo 1520 exhibition at Scherbinka near Moscow last September and RZD has high hopes for the new design and the role it could play in future rail developments in northern Russia.