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Flashcards in MTT test #4 Deck (32)
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1

Cutting fluid Regulations

Federal, state, and local regulations
-Safety
-Pollution
-Waste disposal
-Shipping

2

Hazards of traditional cutting fluids

-Aerosols harm lungs and skin
-Disposal as waste pollute water and environment

3

Types of Cutting Fluids

-Mineral oils
-Emulsifiable (water-based) oils
-Chemical and semi-chemical fluids
-Gaseous fluids

4

Mineral Cutting Oils

PRO
-Noncorrosive
-Excellent lubricating properties
CON
-Poor cooling capability
-High cost
-Tend to become rancid

5

Emulsifiable Oils

PRO
-Increased cooling capacity
-Less expensive
-No fire hazard
CON
-Regular fluid maintenance to control rancidity
-Corrosion risk due to water presence
-Monitor and maintain water level

6

Acceptable Cutting Fluids for HSS and Carbide
Tooling

Most cutting fluids, except gaseous fluids

7

Cutting fluid for Ceramic Tooling?

Not necessary

8

SDS

Safety Data Sheets

9

Choosing a Cutting Fluid

-Fluid selection factors
-Machining operation
-Material being machined
-Refer to manufacturer guidelines

10

Application of Cutting Fluids

-Use to continuously flood work area
-Cool work area
-Carry away chips

11

Gaseous Fluids

PRO
-Clear cut area of removed material
-Eliminate environmental concerns
CON
-No lubricating qualities
-May not adequately cool area between cutter and
workpiece
-Blow chips away at high velocity

12

Chemical Cutting Fluids

PRO
-Dissipate heat rapidly
-Clean to use
-Residue easy to remove
CON
-minimal lubricating qualities
-May cause skin irritation
-Disposal difficult

13

Water-based cutting fluids for magnesium?

No, Burning magnesium reacts violently with water

14

Cutting Fluid Application for lathe operations

The nozzle is usually above the workpiece pointed downward at the tool.

15

Cutting Fluid Application for Internal lathe work

Two air nozzles one adjacent to the lathe and one under the cutting part.

16

Cutting Fluid Application for surface grinding operation.

Special wraparound nozzles are often used on surface
grinders to ensure complete flooding & cooling of the
workpiece.

17

Machinability

The relative difficulty of a machining
operation with regard to tool life, surface finish, and
power consumption.

18

Principles of Metal Cutting

Rake angle
chip
shear angle
depth of cut

19

Tool rake style

Positive /
Neutral --
Negative \

20

Selecting Carbide Tools

Establish the Operating Conditions
Select the Cemented Carbide Grade
Select the Nose Radius
Select the Insert Shape
Select the Insert Size
Select the Tool Style

21

High-Carbon Steels

Are used for files & chisels, and to a limited extent for drilling/turning tools.

22

High-Speed Steels

Used at higher speeds (100 fpm in mild steels) without losing hardness and has long working life.

23

Cemented Carbides

Cemented carbides are the most widely used tool
materials in the machining industry.

24

types of tool ware

Edge ware
Point breakdown
Chipped
Thermal shock
Mechanical
Excess ware

25

Cubic Boron Nitride Tools (CBN)

is next to diamond hardness & therefore can be used to machine plain carbon steels, alloy steels & gray cast irons
with hardnesses of 45 Rc & above.

26

Diamond tools

Industrial diamonds are sometimes used to machine
extremely hard workpieces.

27

Carbide heat exchange

10% Part
10% Tool
80% Chips

28

History of cutting tools

Carbon steel late 1800s
High speed steel
Carbides 1930s
Ceramics cermets 1950s
CBM/ Diamonds

29

Ceramic Tools

Brittle & require machines and setups be rigid & free of vibration.

30

Types of Teeth

Standard tooth
skip tooth
hook tooth