How Do I Choose the Best Hydraulic Fluid?

Hydraulic oil is the hydraulic medium used in the hydraulic system using liquid pressure energy. It plays the role of energy transmission, anti-wear, system lubrication, anti-corrosion, anti-rust and cooling in the hydraulic system. For hydraulic oil, the hydraulic viscosity of the hydraulic device at the operating temperature and the starting temperature should be met first. Since the viscosity change of the lubricant is directly related to the hydraulic action, transmission efficiency and transmission accuracy, the viscosity and temperature performance of the oil is also required And shear stability should meet the various needs raised by different applications. There are many types of hydraulic oils with different classification methods. For a long time, it has been customary to classify by use, and there are also classifications based on oil type, chemical composition or flammability. These classification methods only reflect the earning of oil products, but they are not systematic and it is difficult to understand the interrelationship and development of oil products.

Biodegradable hydraulic oil was developed to meet environmental requirements and control environmental pollution. There are mainly vegetable base oils and synthetic vinegars. Vegetable oils are the main development direction of environmentally friendly lubricants due to their natural biodegradability, excellent lubricating properties, and viscosity-temperature properties. This type of hydraulic oil has no official product in China. But there are many abroad, such as the United States Ryanbo, etc., are formulated from vegetable oil base oils, which can eventually degrade.

Hydraulic systems for automobiles and construction machinery use hydraulic oil as the working medium. In this type of hydraulic system, the fluid velocity is low and the pressure is high, so it is called static pressure transmission. The quality of hydraulic oil will greatly affect the reliability and service life of the hydraulic system. The quality requirements for hydraulic oil are generally as follows:

1) Appropriate viscosity and good viscosity-temperature performance to ensure that power can be transmitted accurately and sensitively under conditions where the operating temperature changes, and normal lubrication of hydraulic components can be guaranteed.

2) It has good rust resistance and oxidation stability. It is not easy to oxidize and deteriorate under high temperature and pressure conditions, and has a long service life.

3) It has good anti-foaming properties, so that under the working conditions of continuous stirring of the oil, the foam produced easily disappears to stabilize the power transmission and avoid the accelerated oxidation of hydraulic oil. ^[1]

Hydraulic oil maintenance work (provided that the equipment is running normally and there are no abnormal conditions).

1. Make sure that the hydraulic oil is not used at high temperatures; the oil will quickly oxidize and deteriorate at high temperatures.

2. The air filter on the hydraulic station should use a filter that can filter both particles and moisture.

3.Using precision

HH, HL, HM, HR, HG, HV, HS hydraulic oils in the GB / T7631.2-2003 classification are mineral oil hydraulic oils. There are many types of such oils, and the amount of use accounts for about the total amount of hydraulic oil. Above 85%, hydraulic oils commonly used in hydraulic systems for automobiles and construction machinery also fall into this category.

Choose the type of hydraulic oil according to the working environment and working conditions. When selecting the hydraulic oil used in hydraulic equipment, you should comprehensively consider and judge from several aspects such as working pressure, temperature, working environment, hydraulic system and component structure and material, and economic efficiency. . Environmental factors include: above ground, underground, indoor, outdoor, coastal, cold, high temperature, and open flame. Operating conditions: pump type, pressure, temperature, material, sealing material, running time. Oil properties: physical and chemical properties. Economy: time of use, oil change period, price.

Industrial hydraulic system

Hydraulic oil is suitable for various types of hydraulic systems in manufacturing and industry.

2. Mobile hydraulic drive system

Hydraulic oil can be effectively used in mobile hydraulic equipment such as excavators and cranes.

3.Marine hydraulic system

Suitable for marine hydraulic systems where ISO HM type hydraulic oil is recommended. ^[2]