1. What is Viscosity?
It is resistance of a fluid to flow. Represented as mm²/s or Centistoke (cSt), it is expressed at a certain temperature.
2. What is Viscosity Index?
It is a value showing the oils to preserve their viscosities against temperature changes. As temperature increases or decreases in an oil with a high viscosity index, its viscosity changes less.
3. What is the main purpose of lubrication?
Minimizing friction between two metal surfaces.
4. What is NAS?
This is the test method determining the distribution of micron level particles within oils. Increasing number and size of particles within a hydraulic oil might cause considerable failures in hydraulic valves.
5. T.A.N. (Total Acid Number)
Provides information on the oxidizing quantity of oils. It is the most important parameter which determines the oil’s useful life.
6. Coolant (emulsion)
Coolant and lubricating products, being two chemically different liquids, can mix homogenously with the assistance of emulgators.
7. How many types of coolants are there?
Coolants are divided into 3 types depending on place of application and operation, namely, mineral based, semi-synthetic and synthetic.
8. What is EP (Extreme Pressure)
Additives which enter into chemical reaction with the metal surface and cause formation of a very resistant film and affect oil film strength positively.
9. What must be taken into account while preparing coolants (emulsions)?
The quality of the water to be used in the emulsion is important for the life of the emulsion. After selecting suitable water and product, physical cleaning of the assembly bench must be performed. In the first fill and top up, proportional dosing pump should be used, or if this is not possible, it must be mixed in an external tank by inserting water and adding product to reach a homogenous distribution and filled on the bench. A good rinsing after cleaning would reduce foaming.
10. Considerations while using coolants (emulsions)
Selecting the right product is the most important parameter. In emulsions, values such as concentration, pH, conductivity must be periodically controlled. The parameters recommended by the manufacturer company must be used in their ranges.
11. Significance of the tramp oils in coolants
Oils mixing into the system from slideway oils or other sources are defined as tramp oils. Ratio of tramp oils must not exceed 3% in the system. Otherwise;
• They will accumulate on emulsion to prevent its aeration (rendering it anaerobic) and cause growth of bacteria in the emulsion.
• Smoke forms in the cutting section.
• Emulsion’s stability is impaired.
• Emulsion’s detergent features are reduced.
• Emulsion’s lubricant and coolant properties are deteriorated.
• They travel the system within the emulsion leaving sticky residues on machine components and working parts. When the system is not operating, the oils accumulating on the emulsion should be skimmed in order to prevent those deteriorations.
12. Why the lives of the Cutting Tools reduce in a Processing Center (CNC Machines)
Working below or over the concentration rates recommended by the authorized technical team, excessive external oil input in the emulsion, failure to use a suitable filter may cause reduction of the lives of the Cutting Tools by the time.
13. Why do the CNC Machines Get Corroded?
Failure to use water within the parameters recommended for emulsions, low oil concentrations, bacteria growth, adding water through the bench are some of the reasons for oxidizing.
14. How can we extend the lives of saws on metal cutting benches?
Saw life on the cutting machines could be increased using high cutting performance (EP additive) products.
15. What is Penetration?
It indicates the hardness or softness of grease and represents density. A penetration value should be selected in consideration of speed in the process, oiling format and period, whether or not working under load or water, rate and values of temperature exposure.
16. Can we mix greases containing different thickeners?
Greases containing different types of thickeners might be incompatible, as a result of which, density and performance deteriorations might be encountered. With regard to compatibility of grease types, you can receive information from technical support team.
17. Can mineral based greases and synthetic greases be applied on the same point?
Information on compatibility should be obtained before mixing mineral based greases and synthetic greases. Even if it is compatible, mineral based grease may adversely affect the performance of synthetic greases.
18. How frequent should the maintenance oils be controlled? (At what frequency they should be controlled?)
Ideally, they should be periodically controlled every three months and trend analysis must be carried out.
19. What is Corrosion?
Corrosion is alteration of metallic structure of metals after reacting with oxidizing chemicals such as oxygen.
20.How are the metal parts processed on the CNC machines with coolant protected against corrosion while retaining, packing and stocking?
For the purposes of corrosion protection, metal parts must be lubricated with a protective lubricant. Particularly, depending on the condition of the processed component (wet or dry), protective lubricant must be selected. In case of wet working part, water repellant protective lubricant class must be preferred.