COOLING WATER SYSTEM
The purpose of cooling water system is to cool engine equipment as well as engine block, inlet air, lube oil and TSC.
Description - Chemical treated water is filled in this system to avoid corrosion, scaling forming and leakages will visible easily.
On WDG3A loco pressurized water cooling system is provided. Centrifugal water pump is provided on left side free end of the engine, which gets drive from extension shaft no. 1 gear. System capacity is 1210 liters. Filling cap provided on expansion tank No.1.
When diesel engine starts, water pump sucks water from four places viz. expansion tank No.1, TSC water return pipe, right side radiator core via after cooler, and left side radiator core via lube oil cooler. Water is pumped at three places viz. right side engine block, left side engine block and TSC.
Right/Left side engine block -The water in right and left side engine block, cools the cylinder liner and after wards rises through jumper pipe to cylinder head to cool it and rises through riser pipe to the respective water return pipe i.e. right side water return pipe and left side water return pipe.
Through right side water return pipe water goes to the left side radiator core via bubble collector and left side water return pipe goes to right side radiator core through bubble collector. In the radiator core water is cooled by radiator fan. Cooled water goes from left side radiator core to lube oil cooler, after cooling lube oil mixes with water of right side radiator core and goes to the water pump again.
Turbo supercharger- Here water cools the intermediate and turbine casing, further it will go to suction side of pump through steam accumulator.
Radiator fan working –Radiator fan works according to the water temperature. Temperature is measured by thermostatic switches viz. ETS1, ETS2 provided in expresser room on water junction box.
The outer drum is coupled with extension shaft No.2 and inner drum is coupled with right angle gear box. There is gap between outer drum and inner drum. Outer drum rotates continuously with main crankshaft. Radiator fan is coupled with right angle gear box with the help of universal coupling.
When water temperature increases up to 680C, ETS -1 operate, R1 contactor will pick up located on back panel. Battery /auxiliary generator current goes to ECC coil through TCR, ECC coil energized, inner drum starts rotating along with outer drum, which in turn rotates radiator fan with the help of right angle gear box, radiator fan works at slow speed and cools the water.
When the water temperature further increases up to 740 C, ETS2 operates, R2 contactor will pick up by pass TCR, radiator fan rotates with full speed and cools the water.
ETS3-When water temperature increases up to 940C, ETS3 operates, hot engine indication lamp will glow on both control desk and alarm bell will ringing, it indicates that engine water temperature is above safe level and requires loco pilot attention to cool down the water temperature. Loco pilot should race the engine to cool down the water temperature according to road and load.
LWS- It is provided in compressor room on radiator room wall, the level of water in expansion tank is 14 inches (water capacity of each tank is 155 litters). Whenever water level is remained 1 inch due to leakage or any other reason in expansion tank that time LWS will operate, engine will shut down with hot engine indication on both the control desk and alarm bell will ring.
A pressurized valve is fitted on any one of expansion tank and water level gauge provided on expansion tank No.2 near long hood headlight. Water level gauge having three zones viz. Green, Yellow and Red.
Water leakage from tell- tale pipe of water pump- Keep watch on the water level, if level goes down inform to PCOR. Lube oil comes from tell-tale pipe of water pump. It is due to the damage of lube oil seal of the water pump.
1. If leakage is drop by drop, watch oil level and work the train, book for repair.
2. If leakage is heavy inform to PCOR.
Engine shut down/not starting with hot engine indication
