About sherry and your coolant

The thick gray-white layer, which the sherry makers fondly called ‘flor’.

I once visited some wine cellars in Jerez in Spain, where I had a glimpse inside the oak wine barrels that they use. Over the surface of the wine, covering it entirely, was a thick greyish white layer which the sherry makers lovingly referred to as ‘flor’. This fermenting layer seems to be what gives the sherry its flavour, but since seeing it, I’ve decided to drink other drinks.

I found myself thinking about this smelly ‘flor’ when I visited a machining company recently. Like at many companies in the industry, the cooling lubricant bath had a thick layer of leaked oil over the top – oil from the machine’s hydraulic system, forming an air-tight layer over the surface of the lubricant. While the sherry makers’ layer was primarily yeast, the oil layer was a hotbed for bacteria and mould.

The machining industry sets great store by favourable working conditions, but the very same industry does not seem to recognise the serious threat to health that cooling lubricant baths can pose. The leaked oil is the ultimate breeding ground for bacteria,

the most common of which are the ‘pseudomonas aeruginosa’, which are infamous for their failure to respond to antibiotics. Pseudomonas aeruginosa are responsible for serious wound infections if they manage to penetrate the skin. Small metal shards in the layer of oil can quickly damage the skin in the event of contact, and the effects of the bacteria in the leaked oil are then serious.

Perhaps you had no idea. Your colleague at the company I was visiting wasn’t either, and was shocked by this ‘secret’. We discussed the possibility of ‘skimming’ the company’s various cooling lubricant baths at regular intervals. Skimmers are able to remove the hazardous layer of oil from the bath very effectively and one mobile skimmer was enough for the company.

If you’d like to know more about skimming and skimmers and how they can help to improve the quality of your end product, extend the service life of your machines and enhance hygiene on the shop floor, check out the page for the Oil Grazer. For pragmatic employers who’d like to advance their quality assurance and working conditions, Hebemann offers an effective solution. Skimming is an investment that will pay for itself very quickly.

Niels Bloemen