MOLYKOTE G-68 Plastic Gear Grease
Harmonization Code : 3403.19 | Lubricating Preparations (With 70% or More Petroleum Oils) For Automotive and Other Uses
Main features
- Good Compatibility with Most Plastics
- 0.014 Coefficient of Friction
- Water-Resistant Grease Lubrication
Product Description
MOLYKOTE® G-68 Plastic Gear Grease is an NLGI 2–3 lubricating grease formulated with mineral oil, polyalphaolefin, lithium soap, extreme-pressure additives and solid lubricants. Developed for plastic gearing, it combines good compatibility with most plastics, high water resistance and a low coefficient of friction. The grease operates across a documented service temperature range of -30 to +140°C and provides load-carrying and wear-protection performance for lubricated mechanical interfaces. Because plastic and elastomer formulations vary, compatibility testing is recommended before use.
Key features
- Plastic compatibility: Provides good compatibility with most plastics; testing is recommended to evaluate swelling, shrinkage, stress cracking and changes in strength or hardness.
- Low-friction lubrication: A coefficient of friction of 0.014 was measured between a steel ball and a POM surface under the documented test conditions.
- Water-resistant performance: High water resistance supports lubrication in plastic gear mechanisms that may encounter moisture.
Applications / Suitable for
- Plastic gears in electrical toothbrushes
- Plastic gears in paper shredders
TDS, SDS & Technical Documents
Technical Specifications
General Properties
Thermal Properties
Additional Information
As-supplied / before-processing properties
Typical values for the grease as supplied. These values are not intended for use as specification limits.
| Property | Value | Unit | Method / condition |
|---|---|---|---|
| NLGI consistency class | 2–3 | — | DIN 51 818 |
| Worked penetration | 250–280 | mm/10 | ISO 2137 |
| Density | 0.85 | g/ml | ISO 2811; 20°C |
| Base oil viscosity | 75 | mm²/s | DIN 51 562; 40°C |
| Drop point | 190 | °C | ISO 2176 |
After-processing / final-state properties
Typical lubrication-performance values under the stated test conditions. These values are not intended for use as specification limits.
| Property | Value | Unit | Method / condition |
|---|---|---|---|
| Service temperature | -30 to +140 | °C | Typical service range |
| Weld load | 1,900 | N | DIN 51 350 T.4; four-ball tester (VKA) |
| Wear scar | 0.75 | mm | DIN 51 350 T.5; four-ball tester, 600 N load |
| Almen-Wieland OK load | 18,500 | N | Almen-Wieland machine |
| Coefficient of friction | 0.014 | μ | Steel ball against POM; ball Ø 12.7 mm, load 6.3 N, speed 10 mm/s, 24 hours |
| Oxidation resistance | 0.1 | bar | DIN 51 808; pressure drop after 100 hours at 99°C |
