PRODUCTS

CALCIUM SULFONATE

Not new to the grease scene, calcium sulfonate thickeners have been around for almost 50 years.
This particular type of grease has inherent extreme pressure (EP) properties that stand out from the rest.
These properties, combined with the fact that it can be formulated for use in H-1 (food-grade) applications, make it an attractive alternative to other greases.

There are a number of grease thickeners available, each with its own strengths and weaknesses.
Briefly, typical lithium-based greases (the most common) are made from a fatty acid, usually 12-hydroxystearic acid, and a lithium base to produce a simple soap which acts as the grease thickener.
Components are then added to give it EP and other desirable properties that allow equipment to run at peak performance.

To make a lithium-based complex grease, part of the fatty acid is replaced with another acid (usually a diacid), which makes the complex soap.
This type of mixed soap structure has special properties that enable the grease to be heated to a higher temperature without losing its structure or oil separating from the thickener.

This maximum temperature is referred to as the dropping point.
The dropping point is critical because it is the point at which the grease reverts back to a liquid (the oil separates from the thickener).
Calcium sulfonate-based greases have a higher dropping point, making them attractive for some high-temperature applications.

Calcium sulfonate greases are made by converting a fluid detergent that contains amorphous calcium carbonate to a grease containing calcite particles.
Because of the calcite particles’ lubricating properties, performance additives containing sulfur, phosphorous or zinc may not be needed.
This is why some calcium sulfonate-based greases are attractive to the food industry.

Calcium sulfonate complex greases deliver improved performance for demanding applications.
This thickener structure proves beneficial in meeting the demands of high loads, temperatures and shear forces in wet and dirty environments.

Calcium Sulphonate Complex (CaS) greases do not function like other greases.
In most greases, the thickener releases the base oil to provide elastohydrodynamic lubrication in a bearing load zone.
A Calcium Sulphonate (CaS) thickener is more like a gel.
The base oil and gelled CaS thickener form a permanent emulsion.

A well formulated CaS grease maintains the emulsified state, and the entire combination of thickener and base oil pass through the bearing load zone.
If the emulsion should break and the base oil bleed from the thickener, the CaS thickener left behind would still lubricate.

The use of higher base oil viscosities to enhance wear protection is applicable to other thickeners, not CaS.
Increasing base oil viscosity can actually reduce the natural wear protection from a CaS thickener and may create the necessity to add molybdenum di-sulfide (Moly) additives to compensate for the reduction in wear protection.
Base oil viscosity does have an impact on the NLGI grade of grease and will affect temperature range.

Calcium sulfonate thickeners are surface active (have a polarity) and provide primary corrosion protection, water washout resistance, and oxidation stability.
Water Washout resistance is achieved from the CaS thickener’s ability to hold water in a tight emulsion and thus keep the water away from metal components.
In turn, this will help to prevent corrosion due to the presence of water in the grease.
Calcium sulfonate greases are often used in long term or for life service applications due to its inherent oxidation stability.

Where the base oils in other grease thickeners do the work, in a Calcium Sulphonate (CaS), it is the thickener that does the work.

Calcium Sulfonate greases are an excellent alternative to traditional Lithium Complex for consistent performance in extreme conditions such as steel mills.
Improved extreme pressure and water resistance are also strong characteristics, making these greases excellent choices for automotive and robotics applications.
In addition, these greases provide inherent rust preventive properties to keep equipment running longer.

Greases have remained to be the ultimate lubricant for many industries and heavy-duty equipment; the grease market has been for years been dominated by lithium-based greases but due to a steady depletion of lithium in the market, the cost of lithium-based greases is rising due to the shortage of this vital material.

Scientists have been working to find alternatives for this challenge, and the viable option that seems to eventually replace lithium-based greases is calcium sulphonate grease.

Selecting the best grease for an important job requires narrowing down the choices based on what's going to perform the best in your specific application.
Calcium, lithium, aluminium, barium, polyuria, even clay are some kinds of thickeners; some of these are markedly superior to others when it comes to holding up at higher temperatures.

This is a grease made from calcium-based soap; it has been improved with TBN that contains sulfur as the main component forming calcium sulphonate grease.
The grease can also be complexed with acetic acid to make it a complex of calcium grease with superior drop-point properties just like lithium complex greases.

Calcium-based greases are known for their high resistance to water washout; unlike lithium-based, their only challenge is that they have a lower drop point which may fail in demanding situations.
A simple calcium-based grease has a drop-point of about 120 °C, while calcium sulphonate grease has a drop point of about 190 °C similar to lithium.
Their high drop points enable them to provide lubrication even at high temperatures between surfaces.

Advantages of Calcium Sulfonate Greases

The grease displays exceptional versatility within various industries, these include:

- High anti-wear and anti-rust performance
- Anti-corrosion properties
- Greater shear stability
- Higher oxidation stability
- Greater shear and mechanical stability
- Higher oxidative Stability
- High dropping points
- Inherently excellent water resistance
- Extremely high load capacity

Preferred Application

Their varied range of benefits and properties make them an excellent choice across multiple industries.

They are ideal for demanding conditions that require extreme load-carrying capacity, excellent water resistance, and high temperatures applications such as; steel mills, paper mills, mining applications, off-highway, and many other heavy-duty industrial machinery.

Off-highway Heavy Duty Calcium
Sulfonate Greases
One of the most widely recognized uses of calcium sulfonate technology today is in off-highway equipment.
Off-highway, heavy duty industrial machinery suffers under the most demanding conditions for lubrication.
Heavy duty equipment manufacturers typically specify grease with a very high load carrying capacity and excellent water resistance.
The base oil viscosity of this type of grease is lower than the steel mill grease at 320 mm2/s for summer or all-season use and 220 mm2/s for cold condition or winter use.
It was decided to formulate a grease targeted at the ISO VG 320 using PIB as well as mineral oil and make it at the stiff end of the NLGI 2 range.
As all of these types of off-highway products contain 5% molybdenum disulfide, it was decided to add 5% of a technical fine grade.
Anti-oxidant and a rust inhibitor were added to the sulfonate along with some passivated polysulfide.