Grease Composition with Segmented Base Oil for Low-Temperature and Life Balance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing grease compositions face challenges in achieving both low-temperature characteristics and extended lubricating life due to conflicting kinematic viscosities of base oils.
Innovation Solution
A grease composition is developed using a base oil blend of high-viscosity, low-viscosity, and ultra-high viscosity hydrocarbon-based synthetic oils, combined with a urea-based thickener where the particle diameter is adjusted to 2.0 μm or less, and a sulfur-phosphorus-based extreme pressure agent.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of operation
If the kinematic viscosity of the base oil is reduced to improve low-temperature characteristics, then low-temperature performance is improved, but lubricating life deteriorates
Solution Approach 1:
The patent segments the base oil into three distinct viscosity components: low-viscosity base oil (for low-temperature flow), medium-viscosity base oil (for balanced performance), and high-viscosity base oil (for lubricating film strength). This segmentation allows each component to fulfill its specific function without compromising the others, resolving the contradiction between low-temperature characteristics and lubricating life
Solution Approach 2:
The patent creates a composite base oil system by combining multiple base oils with different viscosity characteristics in specific proportions (low-viscosity: 10-50 parts, medium-viscosity: 30-60 parts, high-viscosity: 10-40 parts). This composite approach enables the grease to exhibit both excellent low-temperature fluidity and sustained lubricating life through the synergistic effect of the blended components
2Duration of action of moving object
If the kinematic viscosity of the base oil is increased to extend lubricating life, then lubricating life is improved, but low-temperature characteristics deteriorate
Solution Approach 1:
The patent divides the base oil system into multiple viscosity segments, with low-viscosity base oil (kinematic viscosity at 40°C: 2-10 mm²/s) specifically dedicated to ensuring low-temperature fluidity and pumpability, while high-viscosity base oil handles lubricating film maintenance. This segmentation prevents the low-temperature performance degradation that would occur with a single high-viscosity base oil
Solution Approach 2:
The patent optimizes the kinematic viscosity parameters of each base oil component at different temperatures. The low-viscosity base oil provides low resistance at low temperatures, while the high-viscosity base oil maintains adequate film thickness at operating temperatures. The specific viscosity ranges and their proportions are carefully controlled to achieve the desired balance between cold-start performance and lubricating life
3Duration of action of moving object
If a single base oil is used to simplify the composition, then composition complexity is reduced, but it is impossible to achieve both low-temperature characteristics and lubricating life
Solution Approach 1:
The patent segments the base oil into three functional components with clearly defined viscosity ranges and proportion specifications. This structured segmentation provides a systematic approach to achieving both low-temperature characteristics and lubricating life, while the clear parameter specifications maintain compositional simplicity and ease of manufacturing
Solution Approach 2:
The patent establishes specific parameter ranges for each base oil component (kinematic viscosity at 40°C, proportion by mass) that can be controlled during manufacturing. These quantified parameters enable consistent production of the multi-component base oil system without requiring complex formulation processes, thus maintaining ease of manufacture while achieving superior performance
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The present invention provides a grease composition containing a base oil (A) and a urea-based thickener (B). Particles containing the urea-based thickener (B) in the grease composition satisfy a requirement (I). The base oil (A) is a mixed base oil containing a high-viscosity base oil (A1) having a kinematic viscosity at 40°C of 250 mm2/s to 550 mm2/s, a low-viscosity base oil (A2) having a kinematic viscosity at 40°C of 5.0 mm2/s to 110 mm2/s, and an ultra-high viscosity hydrocarbon-based synthetic oil (A3) having a number average molecular weight (Mn) of 2,500 to 4,500 and a kinematic viscosity at 40°C of 25,000 mm2/s to 50,000 mm2/s. The base oil (A) has a kinematic viscosity at 40°C of 25 mm2/s to 105 mm2/s and a viscosity index of 120 or more. Both low-temperature characteristics and a lubricating life can be achieved.