Seal Lip Grease Selection for Low-Temperature Wear Suppression
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In low temperature environments, conventional sealing apparatuses experience lubrication failure due to the sealed fluid not flowing and circulating, leading to wear of the seal lip portion and potential leakage, as the fluid's pour point is reached or exceeded, making it difficult to change the sealed fluid or material without affecting other engine mechanisms.
Innovation Solution
A sealing apparatus with an elastic body and annular seal lip portion, featuring a grease with synthetic hydrocarbon or mineral oil as base oil and a low temperature starting torque of 25 N/cm or less at -30°C, applied to the seal lip portion and sliding surfaces, including the dust lip, to maintain lubrication and prevent wear.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the sealed fluid is changed to one with lower pour point, then low temperature lubrication is improved, but other mechanisms of the engine are adversely affected
Solution Approach 1:
The lubrication system is segmented into two independent fluid systems: the original sealed fluid that remains in the engine and maintains compatibility with all mechanisms, and a separate low-temperature lubricating fluid applied only to the seal lip portion. This segmentation allows each fluid to be optimized for its specific function without compromising overall system compatibility.
Solution Approach 2:
Low-temperature lubrication is applied locally only where needed (at the seal lip portion contact area) rather than changing the properties of the sealed fluid throughout the entire engine system. This localized application maintains compatibility with all engine mechanisms while providing the necessary low-temperature performance at the critical sealing interface.
2Reliability
If the material of the sealing apparatus is changed to improve wear resistance, then wear resistance is improved, but various properties such as heat resistance and pumping performance are affected
Solution Approach 1:
A grease lubricant serves as an intermediary that protects the seal lip portion from wear without requiring material changes. The grease forms a protective film at the contact interface, allowing the seal to maintain its original material properties and associated performance characteristics while gaining wear resistance through the lubricating medium.
Solution Approach 2:
Instead of changing the material parameters of the sealing apparatus, the invention changes the lubrication parameters by introducing a grease with appropriate viscosity and low-temperature flow characteristics. This parameter change achieves wear resistance while preserving the material's heat resistance and pumping performance.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The grease ensures high fluidity and effective lubrication of the seal lip portion even in low temperatures, suppressing wear and preventing leakage by maintaining the required properties of the sealing apparatus without adversely affecting engine mechanisms.
Implementation Method 1
grease is applied to the seal lip portion... the grease ensures high fluidity and effective lubrication of the seal lip portion
Implementation Method 2
the grease contains at least one of a synthetic hydrocarbon oil and a mineral oil as a base oil and has a low temperature starting torque of 25 N/cm or less at -30°C
Data Source
Figure 1
Figure 2
Figure 3
AI summary
There is provided a sealing apparatus capable of suppressing wear of a seal lip portion in a low temperature environment. A sealing apparatus (1) includes an elastic body portion (2) made of an annular elastic body and a reinforcing ring (3) made of an annular metal. The elastic body portion (2) includes an attaching portion (4) fitted in a portion to be attached and a seal portion (5) in close contact with a shaft in a manner the shaft is slidable. Grease is applied to a seal lip portion (51) of the seal portion (5). The grease contains at least one of a synthetic hydrocarbon oil and a mineral oil as a base oil and has a low temperature starting torque of 25 N·cm or less at -30°C.