Polyurethane Elastomer Bearing Material for Propeller Shafts
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current polyurethane elastomer compositions for bearing materials in propeller shafts face challenges in abrasion resistance and swelling resistance, particularly in water lubrication environments, where they tend to experience increased friction and volume changes, leading to higher starting torque and abrasion losses.
Innovation Solution
A polyurethane elastomer composition is developed by combining polyethylene wax and paraffin wax with a cobalt-based compound, optimizing the mass ratios to enhance abrasion resistance and swelling resistance, specifically including 100 parts of polyurethane elastomer, 3-25 parts of polyethylene wax, 1-10 parts of paraffin wax, and 0.1-10 parts of cobalt-based compounds.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If polyethylene wax and paraffin wax are added to polyurethane elastomer, then abrasion resistance is improved, but swelling resistance deteriorates
Solution Approach 1:
The patent applies parameter changes by precisely controlling the amounts of polyethylene wax (3-25 parts by mass) and paraffin wax (1-10 parts by mass) relative to polyurethane elastomer (100 parts by mass). This quantitative optimization resolves the contradiction by finding the optimal balance point where abrasion resistance is sufficiently improved while swelling resistance remains acceptable. The specific ratio ranges represent tuned parameters that simultaneously satisfy both competing requirements.
Solution Approach 2:
The patent creates a composite material system by combining polyurethane elastomer with two different types of wax (polyethylene wax and paraffin wax) and a cobalt-based compound. This composite approach allows the synergistic interaction between components to improve abrasion resistance while the cobalt-based compound specifically addresses swelling resistance, thus resolving the contradiction through material composition design.
2Force
If polyethylene wax and paraffin wax are added to polyurethane elastomer, then coefficient of dynamic friction is reduced, but friction depth increases
Solution Approach 1:
The patent uses parameter changes by optimizing the concentration ranges of polyethylene wax (3-25 parts) and paraffin wax (1-10 parts) to control the surface properties of the bearing material. This precise parameter tuning reduces the coefficient of dynamic friction while limiting friction depth by controlling the amount and distribution of wax components in the composite material.
3Stability of the object's composition
If bearing material swelling is reduced, then volume change rate decreases, but starting torque increases
Solution Approach 1:
The patent employs composite materials by incorporating a cobalt-based compound (0.1-10 parts by mass) alongside the wax additives in the polyurethane elastomer matrix. The cobalt-based compound specifically addresses swelling resistance, allowing the material to maintain dimensional stability with low volume change rate while the overall composite formulation balances the starting torque characteristic.
Data Source
AI summary
Provided are a polyurethane elastomer composition excellent in the abrasion resistance and swelling resistance, and a bearing material formed of the polyurethane elastomer composition. The polyurethane elastomer composition contains a polyurethane elastomer of 100 parts by mass, polyethylene wax of 3˜25 parts by mass, and paraffin wax of 1˜10 parts by mass. Further, preferably the polyurethane elastomer composition contains a cobalt based compound of 0.1˜10 parts by mass.