In the use of construction machinery, sometimes encountered such a situation, the oil cooler in the summer working well but in the winter, there is a phenomenon of oil leakage or even burst, the fault is often mostly in the north. The reason for this is that due to the lower ambient temperature, the oil viscosity increases and the flow resistance increases. For example, for the same oil cooler, if it is in a region with a large temperature difference between winter and summer, in winter, the viscosity of the oil will increase by ten times or even hundreds of times, resulting in a change in flow resistance to the oil cooler. The impact is huge. If there is no overpressure protection device (such as a temperature control valve, etc.) in the system, the pressure will continue to increase because of the lower pressure capacity of the oil cooler, which will eventually exceed the total pressure in the system.
The test pressure of the heat exchanger may cause cracking and oil leakage in a place where the pressure resistance is relatively weak. To solve this problem, we should start with improving the oil circuit design.
After understanding the effects of ambient temperature on the oil cooler, the need to add a bypass circuit to the oil cooler circuit is known. In order to avoid damage to the oil cooler during startup in the colder winter, a more complete oil cooling circuit should be as shown.