Metal Cutting Fluids Why do we need them? вЂў Cooling вЂў Lubrication Also provides:вЂў Swarf Flushing вЂў Corrosion Protection Metalworking Fluids Basic Principles of Metal CuttingFluids ; What they are & how to use them correctly What are neat cutting oils? The performance of a neat cutting oil is influenced by 3 factors:- В» Viscosity В» Additives В» Levels of additives Viscosity Viscosity (at specific temperature) Measured in centistokes (cSt @ 40c) Range from 5 to 40 cSt Water = 1cSt Hydraulic = 32cSt Effects of viscosity Cooling & Swarf Flushing Lubricity Viscosity Viscosity Lubricity additives вЂў Base Mineral Oils Highly refined oils of high, medium or low viscosity вЂў Esters Natural fats Vegetable oils Synthetic esters Lubricity additives вЂў Anti-wear additives Typically phosphorous compounds or ZDDP вЂў E.P. (extreme pressure ) additives Chlorinated paraffins Sulphur Usually sulphurised esters or polysulphides Neat Oils vs Soluble Coolants Cooling Neat Oils Soluble Coolants Lubrication What are coolants? Lubricity Additives Add to water Emulsifiers & detergents Corrosion Inhibitors BioProtection HOCUT ? Metalworking coolant or emulsion Oil in water emulsion Coolant jargon вЂў вЂў вЂў вЂў вЂў Conventional soluble oil Semi-synthetic Synthetic Extreme pressure Biostable Factors affecting Coolant life пЃµMicro-Organisms пЃµTramp oil пЃµWater Quality пЃµSystem Design пЃµPeople Micro-Organisms ( typically bacteria / fungi) Results in:пЃµBad smells пЃµCoolant separation пЃµCorrosion пЃµIncreased disposal costs Common Types Of Micro -Organisms вЂў Aerobic bacteria -live in the presence of air Anaerobic bacteria -live in the absence of air(bad eggs) вЂў Yeasts/ Moulds /Fungi -visible organism (rubber-like) Tramp Oil Oil from positive lubrication & leaks Often resulting in:вЂў Bacteria attack вЂў Coolant separation вЂў Smoke and fume вЂў High disposal cost Water Quality The presence of inorganic salts in coolant make up water will affect:пЃµCoolant stability пЃµFoaming Water Quality Ideal Water Low salts Excessive foaming Hardness = 100-200ppm. Chloride zero Sulphate zero High salts Soap formation Coolant instability Corrosion Bacterial attack Water hardness expressed as ppm. (parts per million ) as calcium carbonate. Coolant mixing Always add oil to water(use a mixing valve if possible) Always mix coolant before adding to the coolant sump Monitoring & control Always maintain concentration between specified limits. Monitoring & control If concentration becomes too high. вЂ“ Possible. skin irritation вЂ“ Expensive (product waste) вЂ“ Foaming Monitoring & control If concentration becomes too low. вЂў Bacterial attack вЂў Corrosion вЂў Increased disposal вЂў Expensive Monitoring and control How is concentration measured? пЃµRefractometer пЃµTitration пЃµInstrumentation --- on-site --- on-site / lab. --- lab. Fluid Concentration Chart 12 .0 R E F R A C T O M E T E R R E A D I N G B R I X Hocut B60 10 .0 8 .0 6 .0 4 .0 2 .0 .0 0 1 2 3 4 5 6 7 8 F L U ID C O N C E N T R AT IO N (%) 9 10 How is Condition Measured? pH readings 4.5 5.0 5.5 6.0 acidic 6.5 7.0 neutral 7.5 8.0 8.5 9.0 9.5 alkaline soluble oils favours bacterial growth acceptable to skin good corrosion protection 10.0 Monitoring corrosion protection вЂў IP 125 Steel swarf on a cast iron plate. (overnight test) вЂў IP 287 Cast iron swarf on a filter paper. (2 hour test ) Soluble Oil Trials Machine Cleaning Antisep Biocidal Cleaner (A.B.C.) kills bacteria & dissolves dirt to ensure the new coolant has a good start. вЂ“ 2-4% A.B.C. circulated with coolant for 24/48 hours вЂ“ Empty & rinse вЂ“ Refill with pre-mixed coolant at correct conc. Health and safety Skincare вЂў вЂў вЂў вЂў вЂў вЂў Handling concentrates Concentration control Hygiene Proper use of skin creams Good housekeeping HSE guide to metalworking Environmental & H&S Issues There is an increasing demand for products that are вЂ�FREEвЂ™- from e.g.:В»Nitrite-free В»Chlorine-free В»PCA -free В»Phenol-free В»DEA-free Environmental & H&S Issues вЂў Nitrite Can react with amines to form вЂ�nitrosaminesвЂ™ (carcinogenic). вЂў DEA -diethanolamine Can react with nitrogen from the air to form вЂ�nitrosamines. Nitrite/DEA in fluids is a health and safety issue, not environmental Environmental & H&S Issues вЂў Chlorine Disposal by burning can form dioxin, a carcinogen Special incinerators needed for safe disposal Disposal cost is very high in Europe Chlorine is an environmental issue, not health and safety FLUIDCARE SERVICES Health risks and MWF mists HSE are demanding that metalworking fluids users should clearly demonstrate that they take every practicable step to control fluids, improve their condition and reduce exposure. MoreвЂ¦вЂ¦вЂ¦вЂ¦вЂ¦ Preventing respiratory diseases and metalworking fluids ScandMist air filtration equipment We recognise that the new guidance on health risks especially regarding asthma and respiratory diseases will pose problems for users. We offer a package of services aimed at helping customers identify the risks and effective measures of prevention and control. вЂў Risk assessment вЂў Fluids testing and bio-audits вЂў Exposure monitoring вЂў Atmosphere control New Scandmist air filtration products are also available to remove both mist and bacteria from machine enclosures. Click on the download to learn more about the issues and to see Houghton products and services. Visit www.hse.gov.uk/metalworking for further information.