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ensures, in addition to controlling the distribution, the operation of six individual injection pumps, supplied with fuel under a pressure of 1.5 kg/cm, The order of injection of the cylinders is I 2. 4. 6, 5. 3. This injection is carried out under a pressure of 28o kg/cm, at the end of combustion at full load, the pressure in the cylinder rises to 55 kg/crn2, the compression ratio being 3 I kg/cm, The injection advance, constant, is 31"; the advance when opening the intake valve is 30.., that of opening the exhaust valve is 50'

The engine cooling water is circulated by a mechanically driven pump, delivering I 820 I per minute; it is introduced at the base of the cylinder block, exits the Diesel engine through the cylinder heads. and goes to radiators located at the front of the locornotive, cooled by a current of air sucked through these radiators by a horizontal axis fan driven by a Texrope belt from the crankshaft of the Diesel engine; this fan ensures a flow rate of 16.5 in'. per second. The temperature of the cooling water is maintained between 65 and 75, By thermostatic control of the shutters located in front of the radiators, shutters controlled by pneumatic servomotor.

The engine is lubricated by a pump delivering 568 I of oil per minute under a pressure of 7 kg/cm' for the nominal speed of the engine; oil, sucked into the engine crankcase, with a capacity of 400 I, branches off at the pump outlet; a small part of this oil goes to a sleeve filter and returns to the crankcase; the majority, sent to the oil radiators, which, located in front of the water radiators, lower the temperature to 60, then goes to the Diesel engine passing through a comb filter: the maximum temperature theoretically reached by the oil is 85, at the connecting rod heads.

A hydraulic type regulator, input. by the camshaft, controls the fuel flow, so as to maintain the speed of the Diesel engine at the value corresponding to the position given by the driver to the throttle lever.

he Diesel engine is also equipped with a centrifuge) type overspeed limiter, also driven by the camshaft, and whose role is to stop the engine in the event that its rotation speed exceeds the nominal speed by Io.

ELECTRICAL EQUIPMENT

The electrical equipment supplied by WESTIN-GHOUSE ELECTRIC C" is the standard equipment of American diesel switching locomotives of I 000 hp. The power of our locomotives being limited to 660 hp and the load of our axles to less than I 8 t, this equipment is practically free from any subject to excessive overheating, regardless of the regime insured (1). It consists of:

- a main generator coupled directly to the Diesel engine,

- a group (auxiliary exciter generator) driven by a Texrope belt from the main generator shaft.

The current delivered by the main generator supplies, through various control or sectioning devices, 4 traction motors suspended by the nose. This generator is also used as a starting motor for Diesel engines; in this case, it is powered by a lead-acid battery with a capacity of 200 A/h. This battery is itself charged at I 30 Volts by the auxiliary generator, which also provides power to the auxiliary circuits (controls, lighting, etc.). The armature of the main generator is mounted, on the collector side, on a spherical roller bearing, while, on the other side, it is rigidly coupled to a sleeve fixed on the shaft of the Diesel engine. Its cooling is ensured by a fan, mounted on the rear of the armature, which draws air from the collector side and discharges this air through the ventilation holes provided on the rear side of the casing.

Automatic regulation of the power requested from the Diesel engine is ensured:

- by an exciter with 3 windings integral with the auxiliary generator, which supplies the excitation winding separate from the main generator;

- by a “Carbonstat” regulator, of the compressed carbon wafer type, combined with the speed regulator of the Diesel engine, which reduces the excitation separated from the exciter if the torque requested from the Diesel engine tends to exceed the maximum torque that it can provide.

The traction motors are series-excited and nose-suspended; they drive each, by a simple gear reducer. one of the extreme axles of the bogies. The 4 motors are permanently coupled in series-parallel, the motors of the even and odd axles being respectively arranged in each of the two branches, in order to reduce the risk of slipping. Electrical shun-cage equipment for inductors allows automatic operation at full field, or at reduced field. These 4 engines are cooled by air blown by two fans mechanically driven by the Diesel engine.

The adjustment of the force developed by the locomotive is obtained by exclusively modifying the speed of the Diesel engine, via a compressed air servo, which bands the springs more or less


(1) At the limit of adhesion. the current circulating in the motors corresponds directionally to the umhorar heating current.