Flashcards in Metalworking Deck (87)
Name three general classifications of fluids used in cutting and grinding.
Soluble oils (petroleum, semi-synthetic, full synthetic)
Mineral cutting oils
Chemical or synthetic coolants
What two primary functions do cutting fluids perform?
What is the most important characteristic of a soluble oil?
It must mix easily with water to form a stable emulsion.
The primary function of a soluble oil emulsion in metalworking is as a ___________.
In order to form a stable emulsion of oil and water, which should be added to which?
Oil is added slowly to water (remember to put the water in the bathtub first before you get in!) OIL-IN-WATER
Why does hard water make it difficult to form a stable emulsion?
Minerals (calcium & magnesium) in the water react with emulsifiers to form insoluble soaps.
Water with a hardness of more than ______ ppm is considered hard.
List best practices to prevent degradation and odors in oil soluble fluids.
Keep the fluid aerated and circulating.
Monitor the condition of the fluid and add biocide as necessary.
Make sure the reservoir and lines are clean and free of bacteria and fungus before adding new oil.
Remove tramp oil.
Keep the system clean and free of contamination.
What is the primary problem encountered with bacteria growth in oil emulsions?
Also rust, corrosion of oil way, filter plugging and dermatitis.
What is skimming of metalworking fluids?
Removal of tramp oil from the top of a soluble oil by means of a belt or other mechanical skimmer.
Name four advantages of tri-purpose cutting oils.
1) Reduce inventory by consolidating lubricants
2) Eliminates tramp oil in cutting oil
3) No possibility of mixing the cutting oil (coolant) and the lubricating oil and putting one into the wrong application
4) Eliminates cross contamination of oils
5) May be used on ferrous & non-ferrous metals
6) Eliminates cutting oil dilution & resultant decreased performance
What material has been used as one of the most effective extreme pressure additives for heavy- duty cutting?
What is the primary effect on a work-piece of using fatty additives in cutting fluids?
Smoother finishes (fatty oils are active at lower temperatures than chlorine or sulfur)
Most EDM (electrical discharge machining) processes are performed with the work-piece submerged in a light petroleum fluid called the ______ fluid.
EDM (electrical discharge machining)
The fluid has a very low viscosity and high dielectric strength.
The ____________ is generally regarded as the primary machine tool and the “father” of all others.
What is a slushing oil?
A temporary rust preventive applied to steel in process.
What is the difference between high speed quenching and marquenching?
In high speed quenching, hot metal is immersed into a low to moderate temperature bath (< 300°F) to control cooling and hardness of the metal.
Marquenching uses a higher temperature bath and a more viscous fluid.
What are ways to stop a cutting coolant from misting?
Use a fluid with an anti-mist additive, change from high pressure, low volume flow of fluid to low pressure, high volume flow.
The primary metalworking operations performed on a lathe are ______ ___ _______.
Turning and boring
Name three other specific operations that can be performed on a lathe.
Single or multi-spindle fully automated machine tools intended for mass production are generically called ___________.
The machine tool capable of compound cutting motions and generally used to produce complex three dimensional shapes is the _______ ______.
Name two basic types of cylindrical grinders?
Center type grinding where the width of the grinding wheel is equal to the length of the cylindrical surface being ground is called ________grinding.
Parts such as long shafts, hollow wrist pins, etc. that can’t be ground on a center type grinder are normally ground on what type of grinder?
What is the primary difference between a shaper and a planer?
With a shaper the workpiece is clamped to a stationary table and the tool moves across. On a planer the tool is stationary and the workpiece moves past the tool.
A __________is a cutting tool that is pushed or pulled past or through the workpiece to produce a machined surface that conforms to the shape of this tool.
The relatively new machine tool that will, in one setup, perform several machining operations on several surfaces of a workpiece, including automatically selecting the proper tool from a storage magazine, is generally called a ________ ________.
Name at least eight machining operations that a machining center can perform?