Under what conditions does hydraulic fluid freeze

Around minus 60.

Hydraulic fluids. Generally, the operating temperature is required to be about 2 degrees higher than the freezing point. For example, the condensation point of HV hydraulic oil is about minus 60.

If this temperature is exceeded, there is a risk of freezing. One of the parameters of the hydraulic oil is the freezing point, when the temperature reaches this value, the oil begins to solidify, the temperature continues to decrease, and the hydraulic oil will freeze.

At low temperatures, if you use summer hydraulic oil, it will solidify, become thick, or even freeze and become unusable. Therefore, winter hydraulic oil is specially added with antifreeze in winter.

The solution to the frozen hydraulic fluid is as follows:

1. To heat the hydraulic oil tank, you can use the oil heating rod, and put the oil heating rod in the hydraulic oil tank to heat the hydraulic oil;

2. After the hydraulic oil is heated, replace the hydraulic oil that is not up to standard;

3. To replace the oil, it is necessary to pay attention to the selection of the appropriate hydraulic oil according to the local temperature.

Because the hydraulic oil does not contain water, it does not freeze, but when the hydraulic oil reaches the freezing point, the hydraulic oil will freeze and not flow.

The pour point is the minimum temperature at which the cooled sample can flow under the specified test conditions. The condensation point refers to the maximum temperature of the oil under the specified test conditions, when the cooled oil surface no longer moves, which is expressed in . It is a conventional index used to measure the low-temperature fluidity of lubricating oil, and the pour point of the oil is slightly higher than the freezing point of several degrees.

Good: The "oil" in the grease usually refers to the liquid part, and the "fat" refers to the solid part, and the oil and grease will change reversibly with the change of temperature, that is, the "oil" that is liquid at room temperature will freeze at low temperature, and the solid "fat" at room temperature will melt into liquid "oil" at high temperature. At low temperatures, the same oil may also show different forms, such as white flocculents, opaque yellow paste, white precipitation, white crystals, etc., and the blended oil of several raw materials is more complex and diverse after freezing, which are normal physical phenomena.

In general, blended oils containing palm, soybean or peanut oil are more susceptible to freezing in winter due to their inherent physical and chemical properties.

Even if it is the same kind of edible oil, it is normal for some to freeze and some not to freeze, and it has nothing to do with quality. Frozen cooking oil will thaw at high temperatures, which will not affect the taste and nutrition.

Defrosting Method:

1.Heat the hydraulic tank. It is not recommended to use blazing to bake, it is very dangerous!

Therefore, the method of electric heating can be considered to increase the heat. For example, the oil heating rod is used, and the oil heating rod is placed in the hydraulic oil tank to heat the hydraulic oil. You can also use electric hot air to blow the bottom of the oil tank, or you can use the steam of the oven steam oven to heat the fuel tank.

2.After the hydraulic oil is heated, replace the hydraulic oil that does not meet the standard, and select the appropriate hydraulic oil according to the local temperature. Do not add other oils or transformers to dilute the hydraulic fluid.

Hydraulic oil not only transmits power, but also has anti-wear and shear properties. After mixing with other oils, the composition of the hydraulic oil changes, the performance deteriorates, and the first damage is the seal, followed by various needle valves, hydraulic cylinders, etc.

Generally, it will not freeze, but it also depends on where it is used, and it is generally below minus 10 degrees for a long time, so you have to add a heater. The lower the temperature, the greater the viscosity of the hydraulic oil, so low viscosity hydraulic oil is generally used in winter.

Hydraulic oil is generally required to be used at a temperature about 2 degrees higher than the freezing point. For example, the back-coagulation point of HV hydraulic oil is about minus 60. If this temperature is exceeded, there is a risk that Hail will freeze.

When the temperature reaches this value, the oil begins to solidify, and the temperature relay continues to decrease, and the hydraulic oil will freeze.

Most substances are thermally expanding and contracting. The same is true for oil, the lower the temperature and the smaller the volume, the greater the density, and therefore the greater the relative density. As a result, the cold oil sinks and freezes gradually, so the oil freezes from below.

Water is different. Water has the smallest volume and the highest relative density at 4. However, when the water temperature drops below 0, the volume expands, and the density and relative density become smaller, and it naturally floats upward. In this way, the water above will freeze first.