What is the difference between hydraulic oil grades 68 and 46?
3 Answers
The main differences between grade 46 hydraulic oil and grade 68 hydraulic oil lie in their viscosity properties and pour points. Below are the specific distinctions between the two: 1. Different pour points: Low-pour-point hydraulic oil plays a crucial role in mechanical transmission systems. In colder environments or conditions with significant temperature variations, hydraulic systems often use hydraulic oil for lubrication, making pour point requirements very important. Pour points of -15 or -30 are necessary to ensure normal operation of hydraulic oil under low-temperature conditions. 2. Grade 46 hydraulic oil has relatively low viscosity, while grade 68 hydraulic oil has higher viscosity. Generally, higher viscosity results in thicker oil film formation. In winter when temperatures are lower, it is recommended to use grade 46 hydraulic oil. Another difference lies in the flash points. As is well known, modern hydraulic oils have their own flash points, so there are also differences in flash points between grade 46 and grade 68 hydraulic oils. Grade 46 hydraulic oil has a relatively lower flash point, making it suitable for different industries and environments. However, both types perform excellently in terms of anti-wear and oxidation resistance.
As a veteran driver with over 20 years of experience, I've seen my fair share of hydraulic system issues. The difference between hydraulic oil grades 68 and 46 mainly lies in viscosity - the number indicates that 68 is thicker, making it suitable for summer heat or heavy-duty work like construction loaders or hot southern regions, as it won't thin out and leak. Grade 46 is thinner with faster flow, ideal for winter or cold climates below freezing - my old truck used it for quicker hydraulic pump response during cold starts. Using the wrong grade is like wearing a thick winter coat in summer - the system will overheat and stutter, drastically reducing efficiency. I once made the mistake of using 46 in hot weather and the machine moved as slow as a snail until I promptly switched back to 68. Remember, always check the equipment manual's recommendation - choosing the right oil for your conditions can save significant repair costs, as small mistakes in this area will bite your wallet hard in a few years.
As a car enthusiast who enjoys modifying various equipment, the choice of hydraulic oil is quite crucial. The No. 68 oil has high viscosity, approximately 68 centistokes, making it suitable for high-temperature or heavy-load scenarios, such as hydraulic systems in excavators or trucks. It resists thinning and leaking under high pressure. On the other hand, No. 46 oil has lower viscosity, around 46 centistokes, and is more suitable for light loads or cold environments, like small forklifts or winter machinery operations, offering quick response and energy efficiency. The difference between the two directly impacts overall machine efficiency. Using the wrong oil can lead to reduced power and increased fuel consumption. I once tested No. 46 oil in a desert region, and the system heat doubled, with oil temperature rising rapidly. Switching back to No. 68 oil stabilized the situation. It's advisable to select oil based on equipment model and operating temperature, avoiding the mistake of using the wrong brand for convenience, as it can damage machine longevity over time.
