Water in Hydraulics: Risks & Prevention Guide

As the "lifeblood" of hydraulic systems, the purity of hydraulic fluids influences the whole operation efficiency and equipment lifespan. However, water intrusion is one of the most common pollution problems in hydraulic systems. How does water intrude into the hydraulic system? What are the other effects once too much water invades the hydraulic system?

 

For example, a sudden malfunction occurred in the hydraulic station of a factory, anti-wear hydraulic oil additives 46# turned into milky white "soy milk". It takes 60,000 yuan to change oils, but only one week, and it emulsifies again. It was found that the water inlet was caused by the failure of the water cooling heat exchanger seal. Ultimately, the machine had to be shut down for a comprehensive maintenance, resulting in heavy losses.

 

How does water intrude into the hydraulic system?

Even though it has taken the most rigorous protective measures, the hydraulic system can not avoid the water intrusion completely. The following are the 4 main ways that water enters the hydraulic system.

• Condensation Water Accumulation

The hydraulic oil box will produce "breath effect" due to the alternating cold and hot working environment -- it sucks in moist air when temperature drops and expels air when the temperature rises. During this process, a large number of water droplets will condense inside the oil tank top and eventually drip to contaminate the hydraulic oil. This problem is particularly serious in areas with large temperature differences between day and night or seasonal humidity variations.

• Leakage of Cooling System

The cooling system or heat changer is the high risk point of water intrusion in hydraulic system. When the sealing parts of the devices aging or the cooling pipe breaks, the cooling water will seep directly into the hydraulic oil. This situation will cause a large amount of water invasion in a short time, which has large damage.

• Hydraulic Cylinder Seal Failure

If the rod is not sealed tightly during the reciprocating motion of the piston rod of the hydraulic cylinder, the water content of moist air will into hydraulic system in the form of water vapor. With temperature changes, the water vapor condenses into fluid water inside the system and mixes with the hydraulic oil. This situation is much common in coastal areas or high humidity environment.

• Oil Store Pollution

If new oils are not protected well during transportation and storage, there might be a certain moisture content. Besides, hydraulic oils are hydrophobic and will absorb water in the air initiatively when exposed to a humid environment. Researches show that putting hydraulic oil in the environment with the relative humidity at 80% for 24 hours can absorb water that as 0.5% volume as the oil itself.

 

 

Analysis of the 7 major hazards of water pollution

It will trigger a chain reaction once the water intrudes into the hydraulic oil and causes multi-aspect damage to systems and equipment.

• Lubricating Performance Drops Sharply

When the water content is much higher in hydraulic oils, the oils will emulsify to form a white and turbid liquid. The strength of the emulsified oil film is significantly reduced, unable to form an effective lubricant film on the friction surface, which leads to the accelerated wear of components and has a substantial shortening of the service life of hydraulic components.

• Overall Corrosion of Metal Workpieces

When water comes into contact with the metal in the hydraulic system, it triggers an electrochemical reaction, which leads to the corrosion of the workpiece surface. These corrosion products will circulate, spread with oils and form a chain corrosion reaction. Rust on the inner wall of hydraulic cylinder can spread to the whole system pipeline within 3 months.

• Additive Failure and Precipitation

Modern hydraulic oil has multifunctional additives, for example, ZDDP will undergo hydralysis reactions with anti-wear agent and antioxidants, etc., generating gelatinous precipitates. These sediments not only fail the additives performance but also clog precision valve components when in service cases.

• Acid Generation and Oxidation Catalytic Effect

Water reacts with the sulfur, chlorine and other elements in oil to form acidic substances, which will accelerate the corrosion of metal pieces and catalyze the oxidation reaction of oil products, generating a large number of sludge pollutants. At the same time, the acid environment can cause a sharp increase in the oxidation rate of hydraulic oil, abnormally raising the viscosity of the oil and generating a large number of oxidation products. These changes accelerate system corrosion and form a circulation, which sharply shortens the service life of hydraulic oil.

• Risk of System Congestion

The sediment and oxidation products caused by moisture will gradually accumulate in the gaps of precision components like servo valves and the inner walls of the cooler pipes. The clog will cause system to react at a low speed at best and cause the components to jam and fail at worst.

• Danger of Freezing At Low Temperatures

In a cold climate, once the water level in hydraulic oil is too high, the water will condense into ice crystals. These crystals may clog the throttle hole of the control valve, jam the servo mechanism, scratch the precision mating surfaces, and cause the hydraulic system failure.

Therefore, good hydraulic oil must have good anti-emulsification properties and can separate oil and water quickly.

Chorus can provide high-quality hydraulic fluid additive components used for formulating all kinds of hydraulic oils.

 

Industrial anti-wear hydraulic oil T5016

T5016 is a hydraulic fluid additive component, which contains many functional components like anti-oxidation, anti-rust, and anti-wear. Using industrial hydraulic oil formulated by T5016 can significantly promote the comprehensive performance of oils. Anti-oxidation additives can delay the aging of oil products, rust preventive agents can protect metal pieces and anti-wear hydraulic oil additives can reduce the wear of metal parts.

These functional performance works together can not only prolong the service life of hydraulic oil effectively, reduce oil change costs but also inhibit the formation of harmful sediment of system to guarantee the long term cleaning and reliable operation of hydraulic oil.

 

Low zinc industrial hydraulic oil T5062

T5062 is mainly composed of high quality additive agents such as, ashless anti-oxidation agents, alkaline zinc-containing anti-oxidation and anti-corrosion additive, anti rust inhibitor and anti-oxidation. The T5062 additives after formulation have excellent oxidation stability that can inhibit the formation of sludge and prolong the service life of oil. Excellent anti-wear performance can protect metal from rusting, good seal compatibility can prolong the service life of hydraulic oil.

 

Chorus can provide you with quality demulsifier through the verification of the market. Demulsifier is a chemical additives that is used to destroy water-in-oil (W/O) type emulsions in lubricating oil. It can speed up oil and water separation rate and improve lubricant oil performance. Chorus DL-32 is a polyether demulsifier additive for lubricant oil that can separate water and oil and prolong the instability time of the emulsion. It is the substitute of LZ 5957.