The solution is to increase hydraulic oil and reduce friction loss.

1. Insufficient lubrication of hydraulic system and heat caused by large friction. The solution is to increase hydraulic oil and reduce friction loss.

2. Environmental problems, high ambient temperature makes the starting point of oil temperature higher, and it is not easy to heat. Solutions to increase heat dissipation to improve cooling effect, or increase the hydraulic tank.

3. Check the hydraulic oil height in the hydraulic tank regularly, work for a long time with some parts, always keep the hydraulic oil level in the normal range, so as to ensure the heat dissipation effect of the tank.

4. To find the cooler gambling match, we should clean up in time to ensure the cooling effect of the cooler.

5. Improper selection of hydraulic oil or poor quality of oil cause excessive oil temperature: excessive viscosity of oil leads to excessive pressure loss of fluid flow, which can be converted into heat energy, which can cause excessive temperature rise; too low viscosity of oil also causes large leakage in working hydraulic pumps and hydraulic components, which can generate heat;

6. The small crane works for a long time, operates improperly or walks for a long time: it works continuously under high pressure and high power, the main safety valve or secondary overload relief valve opens frequently, and the oil circuit and components in the hydraulic system heat up because of long time high pressure.