VP of Technology at RSC, Dr. Larry Beaver, gave a great write up to PTEN magazine.
Excerpt:
Q: Are all multi-purpose lubricants the same?
A: No. Anyone can make a solvent and base oil combo. It takes a real tribologist, an expert in the science of friction and wear, to formulate a lubricant from the ground-up to do everything well. The physical properties such as low viscosity and low surface tension need to be optimized, along with chemical properties to know how the formula behaves across a broad spectrum of usage conditions—from fast penetration at a low temperature to long term lubrication in high heat or severe conditions such as for off road vehicles.
Viscosity and surface tension determine how fast penetrating oil penetrates. Most leading products work fast to penetrate, but that’s only part of the equation. The chemistry of the product also plays a role.
- Penetration (physical property): Some products only focus on penetration, using a solvent that has low viscosity and low surface tension. You end up with product that soaks in fast, but it may be water thin and makes for a poor lubricant…. read more