iquote author=Don Prince link=topic=921.msg19928#msg19928 date=1482005001]
By having the expansion tank pipe connected to the fuel oil venting pipe... As soon as the tank is full of fuel oil, then the fuel oil will enter the expansion tank during refueling?
Regards,
Don_
When you are fueling, the fuel supply pressure forces the compensating water out of the saddletanks thru the compensating waterpipe, the compensating waterpipe ends about 10 cm above the residue water in the saddletanks. Close to the end of the fuelling you are all the time checking the compensating water outletflow from the testcock arrangement discussed. As soon as your testcock is showing fuel, you stop the filling. Possible fuelrests in the compensating watersystem is collected on the top of the inverted U pipe and "expansionbox" and can be drained later, when settled, by the test/draincocks. The headertank pipe ends in the bottom of the box,the possible fuel is on the top, thus you have a considerable, almost 1,5% of the tankvolume buffer to prevent fuel contamination of the compensating water system. This elaborate and complicated system has nothing to do with the environment people, they did not exist in the time of the VIICs, but at all cost to prevent an oilslick which might betray the submarines position.
Tore