Petrofer has been successful in developing water miscible dielubes with wide reaching resistance against microbial attack. This means not only a good stability against growth of bacteria, but also against the growing of yeast and fungi. The latter is especially important when the die lube is applied in a centralised system. Fungi fibres in such a system can easily block filters, sieves and nozzles. In the worst case this may jam the whole production.
It has often been tried to prevent or to stop the growing of microbes by adding conventional
biocides to the dielube concentrates or feeding them to the dilutions. The used biocides
often contain formaldehyde, or depository substances for this agent. Recently however formaldehyde has been increasingly criticised. In France, the use of formaldehydes in metal cutting fluids has been strictly forbidden for a number of years.
Our new biostable dielubes do not contain formaldehyde and they have not to be labeled as dangerous.
The following report shows the difference between a conventional die lube and a biostable one after contamination with bacteria and fungi. The results from the lab completely performed to practice.
For their identification the biostable qualities carry the letters BS in their brand names. At present the mostly used types are DIE-LUBRIC 1060 BS and 1060 BS-2. Further versions for other dilution ratios are available.
Examination of the biostable properties (Contamination test)
1. Producing dilutions in tap water (in this case 1:100).
2. Addition of a highly contaminated emulsion (bacteria 106 and fungis).
3. Measuring the bacteria numbers over a period of time.
4. Measuring the pH-values over a period of time.
5. Checking the contamination with fungis over a period of time.
DIE-LUBRIC 1060 BS is a low wax concentrate. This enables a clean and residue-free performance similar to the wax-free products.
DIE-LUBRIC 1060 BS-2 contains a higher wax content. As a consequence, still stronger release performance and higher dilutability are obtained.
The biostable products will play an important rule in our die lube program in the future.