Stabilizing effect in metalworking emulsions

Stabilizing effect in metalworking emulsions

Naphthenic base oil outperformed par­affinic base oils in an investigation into the emulsion stability of metalworking fluids. Professor Thomas Norrby outlines the implications for formulators of fluids.

“We tested the stability of metalworking emulsions made with several different base oils, and the emulsions made with naphthenic oil were clearly more stable than those made with paraffinic oils,” says Pro­fessor Thomas Norrby, Senior Technical Advisor for Naph­thenics at Nynas.

Until recently, paraffinic Group I base oils were the traditional choice of manu­facturers of metalworking fluids in some markets. But with the threat of shortages hanging over the industry, due to the global decline in Group I capacity, the chase is on to find suitable replacement oils. And as the third wave of Group I refinery closures is about to hit Asia, the Middle East and Africa, Thomas Norrby sends a stark message to formulators:

“Whatever you do, don’t be tempted to use Group II oils in your products!”

The reason for his advice is simple; Group II oil fared particularly poorly in Norrby’s emulsion stability study, the oil was outperformed not only by naphthenic oil but also by Group I and Group I replace­ment base oils.

Intended to be used as a component selection guide for formulators of metalworking fluids, the study identified solvency, expressed in the aniline point, as the key base oil quality. Norrby and his Nynas colleagues used the droplet size as an indicator of emulsion sta­bility – as smaller droplets make more stable emulsions. Two complementary methods for determining droplet size were used and yielded comparable results. The influence of water hardness was also assessed, and was found to play only a minor role in non-ionic surfactant systems, but had more impact in anionic semi-synthetic emul­sion systems.

 wx=

Successful stability

Two methods - droplet size distribution and light scattering/ transmission - were used to study the emulsion stability. The thick­ness of the emulsion phase was determined by light scattering at different time intervals using a Turbiscan instrument, measuring actual concentrations. The Turbis­can Stability Index (TSI) was used to characterise the stability of the different emulsions.

The researchers were able to establish a preferred value for the Hydrophile -Lipophile Balance (HLB) for each base oil type, where the optimum conditions for emulsion stability were found. This HLB value was found to be about two units higher for the naphthenic base oil compared with the paraffinic Group I and II base oils. However, under these conditions, the naphthenic base oil system displayed better drop­let size and stability.

3.10.2017
8713

Articles - Last Added

Wind turbine gears benefit from NUFLUX™ technology – Part 2

Wind turbine gears benefit from NUFLUX™ technology – Part 2

Gabriela Fedor, Frank-Olaf Mähling, Christoph Wincierz, Thilo Krapfl Evonik Operations GmbH – Specialty Additives, Darmstadt, Germany   Justin Langston Evonik ...

1.9.2021 16:22:00
303
Wind turbine gears benefit from NUFLUX™ technology

Wind turbine gears benefit from NUFLUX™ technology

Gabriela Fedor, Frank-Olaf Mähling, Christoph Wincierz, Thilo Krapfl Evonik Operations GmbH – Specialty Additives, Darmstadt, Germany   Justin Langston Evonik ...

2.7.2021 11:10:00
416
Lubrication in environmentally sensitive areas: Making the right choice with esters

Lubrication in environmentally sensitive areas: Making the right choice with esters

While environmental concerns are rising all around the world, lubrication in environmentally sensitive areas is an important issue that needs special attention. NYCO Technical and ...

30.4.2021 11:43:00
593
Calcium sulfonate complex greases in the iron and steel industry

Calcium sulfonate complex greases in the iron and steel industry

Efsun Acar Chemical Engineer Production Coordinator Vario Engineering and Production Technologies Inc. Establishing an iron and steel factory require very high investment ...

4.3.2021 17:46:00
1396
How the PCL market is adapting to rapidly changing environmental conditions

How the PCL market is adapting to rapidly changing environmental conditions

Dr. Colin Morton Dr. Ewan Delbridge Since no unified lubricant solution exists to encompass the changing requirements, only the nimblest manufacturers who can adapt quickly to ...

2.3.2021 15:25:00
955
Energy-efficient hydraulic fluids in industrial equipment

Energy-efficient hydraulic fluids in industrial equipment

Energy efficiency is one of the most important topics of this era. Dr. Holger Pletsch from Evonik Oil Additives, a leading German company which is an expert in the field of ...

31.12.2020 12:15:00
1035
TOTAL pioneers the electric vehicle fluids market with its EV Fluids product series

TOTAL pioneers the electric vehicle fluids market with its EV Fluids product series

Total Lubricants introduced two new product series for electric vehicles whose importance and use are increasing day by day. The company aims to meet the expectations of ...

10.11.2020 11:02:00
1518
Chemical structure of greases in a nutshell

Chemical structure of greases in a nutshell

  Greases are paste-like lubricants that are generally a yield of the reaction between base oils and metal hydroxides with acids and have consistencies ranging from ...

8.11.2020 12:00:00
1606
Metalworking fluid emulsion stability and base oil properties

Metalworking fluid emulsion stability and base oil properties

Prof. Thomas Norrby Nynas AB, Naphthenics TechDMS Dr. Pär Wedin Nynas AB, Naphthenics Research Ms. Linda Malm Nynas AB, Naphthenics TechDMS Emulsion stability is key to ...

8.7.2020 10:50:00
6454
Demand for VII to be sustained by high-quality engine oil sales

Demand for VII to be sustained by high-quality engine oil sales

Changing regulatory environment and strict emission standards are boosting lubricant manufacturers’ demand for viscosity index improvers. Efficiency demands in not only ...

21.12.2019 17:07:00
1912