How can I choose the optimal rubber material?
This article summarizes the most important aspects of choosing the optimal rubber material!
Choosing the optimal rubber material is crucial in the field of sealing technology, as seals are components that prevent the flow of liquids or gases between two or more connected surfaces. Therefore, for an efficient and reliable seal, it is essential to choose the optimal rubber material for seals.
Choosing the optimal rubber material involves several primary considerations in sealing technology. Firstly, chemical compatibility is a key factor. The materials, fluids, or gases present in a given environment or application can have different effects on rubber materials. For instance, if a seal is exposed to oils, acids, alkalies, or other aggressive substances, a rubber material must be chosen that can resist these chemicals without eroding or swelling.
Secondly, the operating temperature is an important factor. Seals must withstand temperature fluctuations without compromising their properties or efficiency. Different rubber materials exist that are specifically designed to function effectively in high-temperature or low-temperature environments.
Additionally, other factors include pressure resistance, wear resistance, UV resistance and weather resistance. Selecting the optimal rubber material takes into account these characteristics, ensuring long-lasting and reliable sealing performance.
In conclusion, choosing the correct rubber material is vital in sealing technology to achieve effective and reliable seals. Considering factors such as chemical compatibility, temperature resistance, and other properties enables the seals to function optimally and have a long service life.
Help for choosing the optimal rubber material
The following table summarizes the main types of materials and their main characteristics. Keeping these in mind will make it easier to choose.
| Main properties and characteristics of the most commonly used vulcanised rubber types | |||||
| NBR (Nitrile rubber) |
HNBR (Hydrogenated Nitrile Rubber) |
Silicone (VMQ, MVQ) (Vinyl silicone) |
Viton (FKM, FPM) (Fluorine rubber) |
EPDM (Ethylene-Propylene-Diene Rubber) |
|
| Hardness (Shore A) | 60-90 | 60-90 | 60-90 | 60-90 | 40-90 |
| Heat resistance (°C) | -50 – +100 | -30 – +150 | -55 – +210 | -25 – +200 | -40 – +150 |
| Tensile Strength | good | excellent | poor | medium | good |
| Elongation | good | good | excellent | medium | good |
| Resilience | medium | medium | good | medium | good |
| Tear resistance | medium | poor | not recommended | not recommended | medium |
| Wear Resistance/ Abrasion resistance |
excellent | excellent | not recommended | poor | good |
| Residual deformation | medium | medium | insufficient | insufficient | not recommended |
| Gasoline | medium | medium | not recommended | excellent | insufficient |
| Mineral oil | excellent | excellent | medium | excellent | insufficient |
| Inorganic acids | medium | medium | medium | excellent | not recommended |
| Inorganic alkalies | poor | medium | not recommended | excellent | poor |
| Hot water | medium | good | medium | excellent | poor |
| Ozone, weather | not recommended | excellent | excellent | excellent | poor |
| Application environment and resistance characteristics | Vegetable and animal oils and fats, mineral oils and fats, (fuel, fuel oil), dilute acids, alkalies, brines, water, air, gases (butane, ethane, methane, propane), hydraulic oils. NOT resistant to aromatic and chlorinated hydrocarbons, glycol-based vehicle brake fluids and ozone contamination. |
Resistant to oils and greases as in NBR materials and to hot water up to 100 °C, good resistance to hypoid gear oils up to +130°C. NOT resistant to aromatic and chlorinated hydrocarbons, vehicle brake fluids. |
Glycol based brake fluids, high temperature air, oxygen, hot water, high molecular weight chlorinated aromatic hydrocarbons. NOT resistant to concentrated acids and alkalies, water above 100°C, steam. |
High temperature vegetable and animal oils and fats and mineral oils and fats, various chemicals (aromatic, aliphatic, chlorinated hydrocarbons), highly oxidizing acids, vacuum, petrol. NOT resistant to acetone, amines, alkalies, vehicle brake fluids, acetic acid, hot water and steam. |
Hot water, steam, air, vehicle brake fluids up to 150 °C, glycol-based fluids, dilute acids, alkalies. Excellent abrasion resistance, resistance to ozone, UV and ageing. NOT resistant to any petroleum products (lubricants, fuels) and hydrocarbons. |