Some automobile engine cooling systems are designed with expansion tanks. The shell of the expansion tank is marked with upper and lower score lines. When the coolant is filled to the online line, it means that the coolant is full and cannot be refilled; When adding coolant offline, it means that the amount of coolant added is not enough, so you can add more; When the coolant is filled between the two lines, it means that the amount of coolant is appropriate.
In addition, the engine should be emptied before adding antifreeze. In the case of unconditional vacuum pumping, the air in the cooling system should be exhausted after adding antifreeze. Otherwise, when the air rises to a certain degree with the engine water temperature, the water vapor pressure in the cooling system will increase.
Extended data:
Connection form of solution expansion tank:
The closed pressure expansion tank shall be directly connected. The closed pressure expansion tank is a closed container, and the lower solution space and the upper gas space are separated by different types of internal diaphragms. When the volume of the system solution increases, the gas in the box is compressed. Its characteristics are that the solution will not contact with the space, will not evaporate, and the accessories such as pipes are not easy to corrode; Reliable operation; Can be set at any height. But the cost is higher.
The open expansion tank adopts direct connection, which is generally a container with an upper opening to the atmosphere. Its characteristics are simple, reliable, easy to operate and low cost. But it must be set at the highest point of the system, and the bottom of the box is required to be higher than the highest point.
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