How to Choose Between Ash-containing and Ash-free Anti-wear Hydraulic Oils?
In a hydraulic system, hydraulic oil plays a vital role. It not only transmits power but also lubricates, anti - wears, and prevents rusting of components in the system. Ash - containing anti - wear hydraulic oil and ash - free anti - wear hydraulic oil are two common types of hydraulic oil. They differ in many aspects such as performance, composition, and application scenarios. A thorough understanding of these two types of hydraulic oil helps with proper selection and usage, ensuring the efficient and stable operation of the hydraulic system.
What is Ash - containing Anti - wear Hydraulic Oil?
The name of ash - containing anti - wear hydraulic oil comes from the additive components in the oil. This type of hydraulic oil usually contains anti - wear additives mainly based on zinc dialkyldithiophosphate (ZDDP). Under extreme working conditions such as high temperature and high pressure, ZDDP reacts chemically on the metal surface to form a protective film with certain strength and toughness. This film reduces the friction coefficient between metals and decreases wear. Since the metal elements (such as zinc) in it will remain as oxides and other forms after the oil burns, forming ash, it is called ash - containing anti - wear hydraulic oil. It is widely used in hydraulic systems that have high requirements for the anti - wear performance of the oil and are less sensitive to ash.
What is Ash - free Anti - wear Hydraulic Oil?
Ash-free anti-wear hydraulic oil uses organic compounds without metal salts as anti-wear additives. Common ones include organic phosphorus compounds and borates. These additives form a dense adsorption film or reaction film on the metal surface through physical or chemical reactions with the atoms on the metal surface, preventing direct contact between metal surfaces and thus achieving anti-wear and friction-reducing effects. Different from ash-containing anti-wear hydraulic oil, because it does not contain metal elements in its composition, no ash will be generated after the oil burns, so it is named ash - free anti - wear hydraulic oil. This characteristic makes it highly favored in hydraulic systems with high requirements for cleanliness.
Applications of Ash - containing and Ash - free Anti - wear Hydraulic Oils Applications of Ash - containing Anti - wear Hydraulic Oil
Industrial Field: In the hydraulic systems of steel rolling mills in steel plants, ash - containing anti - wear hydraulic oil can withstand high - load and impact - type working conditions, ensuring the smooth operation of the steel rolling process. It is widely used in the hydraulic lifting equipment and hydraulic rock drills of mining machinery, adapting to the harsh working environment of mines.
Construction Machinery Field: In equipment such as loaders, excavators, and bulldozers, the hydraulic systems of these equipment experience frequent pressure changes and complex working conditions during operation. The good anti - wear and extreme - pressure resistance of ash - containing anti - wear hydraulic oil can meet their requirements.
Applications of Ash - free Anti - wear Hydraulic Oil
Precision Machinery Field: In the hydraulic systems of high - end CNC machine tools, ash - free anti - wear hydraulic oil can ensure the cleanliness of the system and avoid affecting the machining accuracy of the machine tool due to ash deposition. It is applied in the high - precision hydraulic transmission devices of electronic manufacturing equipment, meeting their strict requirements for the purity and stability of the oil.
Aerospace Field: In the hydraulic landing gear systems and flight control hydraulic systems of aircraft, the quality and performance requirements for hydraulic oil are extremely high. Ash - free anti - wear hydraulic oil is widely used because of its good low - temperature performance, oxidation stability, and cleanliness. In the attitude control hydraulic systems of satellites, ash - free anti - wear hydraulic oil ensures the reliable operation of the hydraulic system in the special space environment.
Differences between Ash - containing and Ash - free Hydraulic Oils
Composition Difference: The main anti - wear additive of ash - containing anti - wear hydraulic oil is metal salts containing zinc, such as zinc dialkyldithiophosphate (ZDDP). These metal - salt additives will generate ash after the oil burns while playing an anti - wear role. Ash - free anti - wear hydraulic oil uses organic compounds without metal elements as anti - wear additives, such as organic phosphorus compounds and borates. After the oil burns, there is no ash residue. It has better hydrolytic stability, filterability, and no corrosion to silver - plated parts.
Performance Feature Differences: Under normal working conditions, both can provide good anti - wear protection. However, under extreme conditions such as high temperature and high pressure, ash - containing anti - wear hydraulic oil shows more prominent anti - wear performance due to the chemical reaction film formed by its metal - salt additives. In terms of oxidation stability, since ash - free anti - wear hydraulic oil does not contain metal ions, which reduces the catalytic effect of metal ions on the oxidation of the oil, its oxidation stability is relatively better during long - term use, and the service life of the oil is longer. In terms of cleanliness, ash - free anti - wear hydraulic oil does not produce ash, and it will not block the filter due to ash deposition in the hydraulic system, affecting the normal operation of the system. Its cleanliness is significantly better than that of ash - containing anti - wear hydraulic oil.
Applicable Equipment Differences: Ash - containing anti - wear hydraulic oil is suitable for hydraulic equipment with harsh working conditions, high requirements for the anti - wear performance of the oil, but relatively low requirements for cleanliness, such as large - scale industrial machinery and construction machinery. Ash - free anti - wear hydraulic oil is more suitable for equipment with extremely high requirements for cleanliness and precision, such as precision machine tools and aerospace equipment.
Test Items | Ash - containing Hydraulic Oil | Ash - free Hydraulic Oil |
Ash Content | High | None |
Metal | Zinc or others | None |
Thermal Stability | Medium | Good |
Hydrolytic Stability | General | Good |
Copper Corrosion | High possibility | Low possibility |
Pump Adaptability | Adaptable | Adaptable |
Environmental Pollution | High possibility | Low possibility |
Cost | Medium | High |
Selection Principles of Ash - containing and Ash - free Hydraulic Oils
Selection Based on Equipment Working Conditions: If the equipment operates under high - temperature, high - pressure, high - load, and high - impact working conditions, such as large - scale steel rolling equipment in the metallurgical industry and heavy - duty mining equipment in mines, the anti - wear and extreme - pressure resistance of ash - containing anti - wear hydraulic oil can better meet the requirements, and ash - containing anti - wear hydraulic oil should be given priority. For equipment that starts frequently in a low - temperature environment, has relatively stable working pressure, and has high requirements for cleanliness, such as aerospace equipment and high - end electronic manufacturing equipment, the low - temperature performance and cleanliness advantages of ash - free anti - wear hydraulic oil are obvious, and it is more suitable for such equipment.
Selection Based on Equipment Precision Requirements: For ordinary industrial equipment with low precision requirements, ash - containing anti - wear hydraulic oil can meet the anti - wear requirements and has a relatively low cost, which can be an affordable choice. However, for high - precision equipment such as precision CNC machine tools and optical instrument manufacturing equipment, even a small amount of ash deposition may affect the accuracy and normal operation of the equipment. In this case, ash - free anti - wear hydraulic oil must be selected.
Consideration of the Sealing Materials of the Hydraulic System: Some sealing materials may react chemically with certain additives in ash - containing anti - wear hydraulic oil, causing the seals to age, deform, or even fail. If the hydraulic system uses special sealing materials, when choosing hydraulic oil, it is necessary to carefully check the compatibility list provided by the seal material manufacturer to ensure that the selected hydraulic oil will not damage the seals. If the sealing material is sensitive to the additives in ash - containing hydraulic oil, ash - free anti - wear hydraulic oil should be selected.
Combination with the Recommendations of the Equipment Manufacturer: When designing the equipment, the equipment manufacturer will give clear recommendations on the selection of hydraulic oil according to the performance characteristics and working requirements of the equipment. When choosing hydraulic oil, it is necessary to refer to the technical manuals and recommendations provided by the equipment manufacturer and select the hydraulic oil type and specifications that meet the requirements to ensure the normal operation of the equipment and the warranty rights. Ash - containing anti - wear hydraulic oil and ash - free anti - wear hydraulic oil differ in composition, performance, application scenarios, and selection principles. When choosing hydraulic oil, users need to comprehensively consider various factors such as equipment working conditions, precision requirements, sealing materials, and the recommendations of the equipment manufacturer, and reasonably select hydraulic oil to ensure the efficient and stable operation of the hydraulic system and extend the service life of the equipment.
The Price of Additives for Ash-containing and Ash-free Anti-wear Hydraulic Oils
The price of Additives for Ash-containing and Ash-free Anti-wear Hydraulic Oils depending on factors such as brand, specification, composition, and sales channels. If you are interested in Additives for Ash-containing and Ash-free Anti-wear Hydraulic Oils, please feel free to contact us.
Supplier of Lubricant Additives
UNPChemicals is a professional supplier of high-quality and effective Lubricant Additives. We offer several remarkable products, namely Amine-neutralized hexyl phosphate PSAIL 3490,Amine-neutralized mixed phosphate Esters PSAIL 2280,Phosphorothioate acrylate derivatives PSAIL 3530,etc.
Amine-neutralized hexyl phosphate PSAIL 3490 is a specialized mixture of amine phosphate salts known for its multifunctional ashless additive characteristics. As an ashless additive, PSAIL 3490 does not produce ash as combustion by-products, reducing engine deposits and harmful emissions. PSAIL 3490 is a multifunctional additive, providing a range of benefits in a single product, making it highly versatile and cost-effective.
Amine-neutralized mixed phosphate esters PSAIL 2280 is a multifunctional ashless additive structured as a phosphate ester amine salt with excellent load carrying capacity, anti-wear and corrosion protection properties. As a multifunctional additive, PSAIL 2280 reduces the amount of anti-emulsifier and rust inhibitor and has good tribological properties, especially at higher temperatures, forming thicker boundary lubricant films. In addition, PSAIL2280 is widely used in metalworking fluid formulations in conjunction with sulfur carriers because of its good anti-wear properties.
Phosphorothioate Acrylate Derivatives PSAIL 3530 is an ashless EP/AW additive with dialkyl dithiophosphate structure, especially suitable for industrial lubricating oils with FZG test requirements, such as industrial gear oil, anti-wear hydraulic oil containing ZDDP, lubricating grease and metal processing oil.
Conclusion
Hydraulic oil is crucial in hydraulic systems for power transmission, lubrication, anti - wear, and rust prevention. Ash - containing and ash - free anti - wear hydraulic oils are two common types with differences in composition, performance, and application scenarios. Ash - containing ones, with zinc - based additives like ZDDP, form a protective film under extreme conditions but leave ash after burning, suiting harsh - condition and high - anti - wear - demand systems like in industrial and construction machinery. Ash - free oils use metal - free additives, have no ash residue, better oxidation stability and cleanliness, and are ideal for precision and high - cleanliness - required fields such as precision machinery and aerospace. When choosing, factors like equipment working conditions (high - temp/high - pressure for ash - containing, low - temp and high - cleanliness for ash - free), precision requirements (low - precision for ash - containing, high - precision for ash - free), sealing material compatibility, and equipment manufacturer's recommendations must be comprehensively considered to ensure the hydraulic system's efficient and stable operation and extend equipment lifespan.
UNPChemicals supplies various lubricating oil additives such as friction modifiers, metal deactivators, extreme pressure anti-wear agents and metal processing additives. If you're interested, please contact us.