What lubricants are used in diesel engines

Of course, such large engines must be adequately lubricated and cooled. Especially with the lubrication the diesel engine had to be carefully assembled. The fast moving parts of an internal combustion engine therefore had to be provided with intensive lubrication. It is therefore not surprising that a lot of emphasis has been placed on it here too. This was also shown by the surveillance with the Woodward regulator.

That for them lubrication of the diesel engine lubricant stored in a tub mounted under the engine. These sump held 360 liters of lubricating oil.

Commercially available diesel engines were also used in the Bm 4/4 series oil for combustion engines. This lubricant was also for the lubrication the turbocharger (0.8 liters) and for the Woodward regulator (2 liters) used.

The lubricating oil pump driven by the crankshaft sucked it in lubricant from the sump and pressed it through the Winslow fine filter and the oil cooler.

Both Locomotives with the numbers 18 427 to 18 446 a slit filter was also used. This solution ensured that the lubricant freed from pollution on one for the lubrication optimal temperature was brought.

That was special Oil pump more lubricant promoted when the lines in the diesel engine could accommodate. This created an overpressure in the line of up to eight bar could be. Excess lubricating oil was therefore fed back into the pan. That made that too oilin the sump cooled down. This ensured that there was always enough lubricant in the engine during operation.

The lubricant then returned to the tank under the engine by gravity. The lubricant also removed dirt and partly cooled the components of the diesel engine. Due to the large volume, the lubricant and the im calmed down oil Contained dirt sank to the bottom of the tub. Therefore, the lubricant had to be replaced regularly.

Because of this structure, when starting the engine, some time could pass before the lubricant had reached the engine, the engine had to stand still after a long period of time and with preparation manually pre-lubricated.

This was with the Locomotives with the numbers 18 401 to 18 426 a manual pump is available that the lubricant from the sump directly into the engine. The remaining machines had a prelubrication pump.

With the manual solution it could happen that too little was pre-lubricated. When the diesel engine was started, that was it lubrication insufficient and no pressure could be built up.

In this case, the Woodward regulator off and the engine could not be started. The process therefore had to be repeated. With the prelubrication pump, the engine could only be started after the prelubrication was completed.

That was enough to cool the diesel engine lubricant nowhere near enough. The large amount of heat generated by the combustion therefore had to be dissipated from the engine by other means.

Cooling with air could not dissipate the heat sufficiently with this performance class either. That is why they also built Locomotives a liquid-operated cooling system for the diesel engine in this series.

The liquid-operated cooling system of the locomotive consisted of two interconnected, but independently working circuits. The important main circuit was used to cool the diesel engine and the two Exhaust gas turbocharger. The second circuit, known as the secondary circuit, was responsible for the charge air cooler and the lubricating oil cooler. This achieved an optimally designed cooling.

Each circuit had its own pump driven by the crankshaft of the diesel engine. As a result, everyone was autonomous and could be operated with optimal temperatures.

The pump delivered that Coolant from the coolers directly to the components to be cooled. Then that happened cooling water back to the coolers. This created a closed cycle.

The distribution of these cooling elements was not the same throughout the series. The first Locomotives with the numbers 18 401 to 18 426 the cooling elements 7/5 were distributed.

This gave the main circuit a slightly larger cooling surface. With the rest Locomotives the distribution was then the same and each circuit had six cooling elements. However, this had no effect on the functioning of the cooling.

The cooling system contained 460 liters of water. This was distributed with 320 liters in the main circuit and with 140 liters in the secondary circuit. The cooling water Corrosion protection was added. Its concentration was just under 1%. Other additions, such as a Antifreeze there was at the locomotive not, so that the water had to be drained via the existing emptying when driving over in a towed state.

Since that cooling water the locomotivelike all of those back then Diesel locomotives of the Swiss Federal Railways SBB no Antifreeze owned, had to be prevented, especially in winter, that the water could freeze when the diesel engine was switched off. That would have meant that the engine would have been blown up by the force of the water. This would have caused serious damage to the engine.

Therefore, the cooling system was equipped with an electric cooling water heater with an electric circulation pump from the state network. The parked locomotive was therefore always connected to the electrical current with a cable and preheated. The voltage required for this was 380 voltsThree-phase current and it was available at the usual storage locations for the locomotive. However, the required cable was not carried.

The Preheating system had several reasons. For one thing, that was prevented cooling water in the locomotive could freeze. On the other hand, the engine could be spared because it does not cause any harmful effects Cold start would have. Since that Cab was heated via a water heater from the cooling system of the engine, thanks to the preheating system it was also possible to prevent the windows from becoming covered with hoarfrost in winter.

The storage tanks, which also served as expansion vessels for the water, were located above the water coolers. They could be filled with two at the front Stem attached sight glasses are checked. The containers were connected by pipes to the associated circuit and to each other. In this way, the water level in the entire cooling system could equalize. Nevertheless, the systems always had to be very well filled.

In order to also cool the water, the surface of the cooler was designed in such a way that the heat could be dissipated with an artificial circulation. However, the natural circulation was only sufficient when the diesel engine was idling. For this reason, the monitoring of the cooling was designed in such a way that the engine switched to idling if the pressure in the lines fell below the specified value.

A fan was used to cool the cooler, which supplied the cooling air from the outside via the side of the Stem attached movable blinds sucked in by the cooling elements.

The cooling air was then expelled upwards and released into the open. This enabled the Train stations effectively prevent the warm cooling air from escaping to the side and possibly annoying travelers and staff.

The fan was driven by a hydrostatic system. The one used for this Hydrostatic oil was set in motion by a pump and stored in a special container.

This hydrostatic pump was in turn connected to the crankshaft of the diesel engine via V-belts. This means that the pump ran at the moment when the diesel engine was started. The fan was ready.

The fan was controlled by the temperature of the Cooling water. There were also special ones Valves available. If this moved within a small range, the fan stopped and the slats on the side were closed. When the water began to heat up, the blinds were opened first. This started natural cooling and heat was already being dissipated. However, the fan was still off.

The warmer the water, the faster the fan ran and the blinds opened accordingly. At full power these stood out clearly and the fan ran at full speed. The flow through the cooler was now at its maximum level. This provided sufficient cooling that was able to dissipate enough heat even under full load of the diesel engine. So there was good cooling.

The temperature rose in the cooling water to over 90 ° C, the diesel engine was switched to idle and the Hydraulic static system fully opened. The fan was now at full speed power operated and the cooling water cooled further. Switching off the diesel engine would have prevented cooling, however, because the pump would then also no longer work. Therefore, the engine was not allowed to be switched off after driving at full load.