1. Part 2 – Machine Movements and Actions
MACHINE GUARDING
Part 2 – Machine Movements and Actions
NOTES:
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2. Statements in Italics are meant as a guide for you, a recommendation of what to do.
3. The word DISCUSSION indicates that the slide content is organized in a Question and Answer format. After you read each question, have students shout out the answers or call on students. Repeat answers as needed so everyone can hear them.
4. “----” indicates a short pause to give students time to answer the question.
5. The words in bold appear on the slide.
end NOTES
Today we are going to talk about types of machine movements and actions. ▼

2. Safety is Our Most Important Job
Remember, safety is our most important job. ▼

3. Machine-related Injuries
What are possible causes of injuries in a machine shop?
DISCUSSION: Think about the possible causes of injuries in a machine shop. What comes to mind?
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4. Machine-related Injuries
A large workers’ compensation insurance company analyzed over 4,000 claims submitted by metal fabrication companies between 2010 and This chart shows the tasks performed when workers got injured in machine-related accidents.
-31% of the injuries occurred during machine operation
-21% of the injuries occurred during workpiece and material handling
-15% of the injuries occurred during machine setup and adjustment
DISCUSSION: Point out and discuss the similarities and differences between student responses and what this slide shows. ▼

5. Machine Hazards Types of movement Machine actions .
There are many ways to to think about machine hazards.
The simplest way is to think about:
the types of movement of machine parts,
and machine actions.
All types of movement and actions need guarding. ▼ .

6. Machine Motions Rotation Reciprocating Transverse
Before thinking about guarding, it important to consider the different types of machine motions. These include:
rotation
reciprocating
and transverse.
These motions are basic to nearly all machines. Now let’s talk more about each of these motions. ▼

7. Rotation Rotating Coupling with Projecting Bolt Heads
Rotating Shaft and Pulleys with Projecting Key and Set Screw
Rotating motion can be dangerous. Even smooth, slowly rotating shafts can grip hair and clothing, and force a hand and arm into a dangerous place. ▼
Rotating motion is found in couplings, cams, clutches, flywheels, ▼
and shafts, pulleys, spindles, and meshing gears. ▼

8. Rotation  Nip Points Parts rotating in opposite direction
Parts can rotate in opposite directions or tangentially.
Rotating movements create nip points.
This hazard is common on machines with intermeshing gears, or with rolling mills. ▼
Parts rotating in opposite direction
Rotating and tangentially moving parts

9. Nip Points Between Rotating and Fixed Parts
Nip points can also occur between rotating and fixed parts that create a shearing, crushing, or abrading action. Examples include: ▼
Spoked flywheels ▼
Screw conveyors, ▼
and Abrasive wheel grinders with incorrectly adjusted work rests and tongues. ▼
Screw conveyor and fixed trough
Spoked flywheel
Abrasive wheel on a grinder

10. Reciprocating Reciprocating motion can be hazardous.
During the back-and-forth or up-and-down motion, a worker may be struck by or caught between a moving and a stationary part. ▼

11. Transverse
Transverse motion is movement in a straight, continuous line.
A worker may be caught in a pinch or shear point by the moving part. ▼

12. Point of Operation Where the work gets done Machine Actions:
drilling cutting punching
bending grinding shearing
The Point of operation is where the work gets done. ▼
Examples of Machine Actions include cutting, shearing, punching, bending, and grinding.
Let’s look at each one of them:▼

13. Drilling and Cutting
Drilling and cutting action may involve rotating, reciprocating, or transverse motion.
The danger of the cutting action exists at the point of operation where injuries can occur.
In addition, flying chips or scrap material can strike eyes or face. ▼

14. Shearing
Shearing action involves applying power to a slide or knife in order to trim or shear metal or other materials.
Shearing machines can be mechanically, hydraulically, or pneumatically powered. ▼

15. Punching and Bending
These pictures illustrate punching and bending actions. ▼

16. What hazards do you see on this machine?
DISCUSSION: What hazards do you see on this machine or you anticipate will occur when the machine is operated?
----
Nip points can occur between rotating and fixed parts. These may cause serious trauma if a person’s hand is pulled into the wheel.
Other hazards may include: flying chips, sparks, or the possibility of wheel explosions. ▼

17. What hazards do you see?
DISCUSSION: What hazards do you see in this picture?
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There is no guard on the power transmission mechanism. Rotating parts create nip points that can result in entanglement.
A guard should be placed over the power transmission if it is located less than 7 feet above the floor. ▼

18. Learning to Look No tool rest No tongue guard
What hazards do you notice here? ▼
Note there is no tool rest
and no tongue guard is present. ▼

19. Questions?
In this presentation we covered basic machine movements and actions. Do you have any questions? ▼

20. End of Part 2 Machine Movements and Actions
Next we will learn about machine guards.