Welding Hazards and Techniques Quiz

Workshop Hazards

• Four hazards in a welding shop include: Electric shock, fire, fumes, and noise
• In a welding shop, electric shock can occur due to faulty electrical wiring or equipment, as well as accidental contact between welding equipment and conductive objects.
• Fire can be started by welding sparks igniting flammable materials, such as wood, paper, or cloth
• Fumes produced by welding can be toxic and harmful, potentially causing respiratory problems.
• Noise from welding can be excessive, leading to hearing damage

Welding Techniques

• Gas welding uses a flame produced by burning a fuel gas with oxygen.
• Two common gas welding techniques include oxy-acetylene welding and oxy-hydrogen welding.
• Oxy-acetylene welding uses a mixture of acetylene and oxygen to create a high-temperature flame, ideal for joining different metals.
• Oxy-hydrogen welding utilizes a hydrogen and oxygen mixture to produce a flame for welding, typically used for thin metal sheets and intricate work.

Electric Arc Welding

• The electric arc welding process involves an electrical arc established between a welding electrode and the workpiece.
• The arc generates intense heat, causing it to melt material from the electrode and workpiece, forming a weld pool.
• This process requires an electric power source and a welding circuit that includes a welding cable with positive and negative connections.
• Straight Polarity in arc welding refers to the positive connection being attached to the electrode, while the negative connection is attached to the workpiece.
• Reverse Polarity describes negative connection to the electrode and positive connection to the workpiece.

Cutting Oil Objectives

• Four objectives of cutting oils in machining include:
• Cooling: Cutting oils help to reduce heat generated during the machining process. This minimizes tool wear and workpiece distortion.
• Lubrication: Cutting oils provide lubrication between the cutting tool and the workpiece, reducing friction and improving surface finish.
• Chip Removal: Cutting oils help to flush away chips, preventing them from clogging up the cutting tool or workpiece.
• Corrosion Prevention: Cutting oils can protect the workpiece from rust and corrosion.

Turning Safety Precautions

• Turning: Four safety precautions include
• Never wear loose clothing to avoid it getting caught in the lathe.
• Keep your hands and fingers clear of moving parts.
• Always use a tool holder and never hold the cutting tool directly.
• Ensure proper tool sharpening and avoid using dull cutting tools.

Milling Safety Precautions

• Milling: Four safety precautions include:
• Never use a milling machine without proper training.
• Ensure the workpiece is securely clamped to the table.
• Keep your hands and fingers away from the cutter.
• Always wear safety goggles to protect your eyes from flying debris.

Gas Welding Safety Precautions:

• Gas welding: Four safety precautions include
• Always use appropriate safety goggles to protect your eyes from the intense light and flying sparks.
• Ensure adequate ventilation during welding to prevent buildup of harmful fumes.
• Store gas cylinders properly to minimize the risk of accidental leaks or explosions.
• Never use welding equipment without proper training.

Arc Welding Safety Precautions:

• Arc welding: Four safety precautions include
• Always wear a welding helmet or mask with appropriate shade lenses to protect your eyes from intense UV radiation.
• Appropriate leather gloves to protect hands from sparks and burns.
• Keep a fire extinguisher readily available in case of a fire.
• Ensure adequate ventilation to prevent buildup of harmful fumes.

Vernier Caliper Zero Errors

• Vernier caliper zero error is the discrepancy exhibited when the jaws are closed, and the zero marks on the main scale and vernier scale don't align perfectly.
• Zero error determines the error in measurement.
• A positive zero error occurs if the zero mark of the vernier scale is to the right of the zero mark on the main scale. Measurement is less than the actual measurement.
• A negative zero error indicates that the zero mark of the vernier scale is to the left of the zero mark on the main scale. Measurement is more than the actual measurement.

Milling Machine Processes

• Processes that can be achieved on a milling machine include:
• Milling grooves
• Milling slots

Lathe Machine Operations

• Operations that can be achieved on a lathe include:
• Turning: Removing material from a workpiece to create a cylindrical or conical shape.
• Facing: Machining a flat surface on the end of a workpiece.
• Drilling: Creating holes in a workpiece.
• Boring: Enlarging existing holes.
• Threading: Creating threads on a workpiece.
• Knurling: Creating a roughened pattern on a workpiece for gripping or decorative purposes.

Consumable Electrode Welding Processes

• Two consumable electrode welding processes include:
• Shielded Metal Arc Welding (SMAW): An electrode coated with a protective flux is consumed during the process.
• Gas Metal Arc Welding (GMAW): A continuous wire electrode feeds into the weld pool, while a shielding gas protects the weld from contamination.

Turning Operations

• The component to be turned from a 60mm diameter shaft on a lathe machine involves the following five operations:
• Turning: Creating a cylindrical shape with a specific diameter (e.g., 50mm).
• Facing: Machining a flat surface on the end of the component.
• Chamfering: Creating a small angled bevel at the edges for improved aesthetics or stress reduction.
• Grooving: Cutting a groove or channel for mechanical purposes (e.g., for an O-ring seal or a bearing race).
• Threading: Creating threads on the component for attaching other parts.

Workshop Safety Precautions

• Before Entering a Workshop:
• Wear appropriate safety gear and clothing, including safety shoes with steel toes, safety glasses, and long pants.
• Ensure the workshop is properly lit and ventilated.
• Be aware of potential hazards and obstacles, including slippery floors, exposed wires, and sharp edges.

Workshop Safety Precautions

• After Workstation:
• Clear any spills or debris.
• Ensure tools are safely stored and secured.
• Switch off machinery and unplug equipment when not in use.

Workshop Safety Precautions

• When Leaving:
• Ensure the workshop is clean and organized.
• Report any safety hazards to the supervisor.
• Lock all doors and windows upon leaving.

Filing Problems

• Two filing problems:
• Chattering: An uneven, wavy surface caused by the file vibrating.
• Loading: The file's teeth become clogged with metal shavings and lose their cutting ability.

Solving Filing Problems

• Solving chattering:
• Reducing cutting speed
• Using a file with a finer cut or tighter teeth.

Solving Loading:

• Using a file with a coarser cut
• Brushing or tapping the metal shavings away.

Causes of Accidents in Workshops

• Five causes of accidents in workshops :
• Improper use of tools and equipment.
• Lack of safety awareness and procedures.
• Distractions and carelessness.
• Faulty or poorly maintained equipment.
• Inappropriate protective clothing.

Drilling Machine Operations

• Five operations achieved by a drilling machine
• Drilling: Creating holes in a workpiece
• Spot drilling: Creating a small pilot hole to guide the drill bit.
• Reaming: Enlarging and smoothing existing holes.
• Counter boring: Creating a wider, flat-bottomed cavity in a hole.
• Tapping: Creating internal threads in a hole.

Measurement and Inspection

• Measurements and inspection are separate but related concepts in engineering.
• Measurement: Determine the size, shape, or other physical characteristic of an object.
• Inspection: Assessing if an object meets specific requirements or standards.

Marking Out Tools

• Six common marking out tools in engineering workshops:
• Steel rule: Measuring lengths and marking lines.
• Divider: Transferring measurements and marking circles.
• Scriber: Marking lines on metal surfaces.
• Try square: Checking for right angles.
• Protractor: Measuring angles.
• Center punch: Marking the center of a workpiece.

Timber Seasoning Methods

• Artificial timber seasoning: Accelerating the drying process to reduce moisture content.
• Two artificial methods of timber seasoning include: Kiln drying: Utilizing a controlled environment with high temperatures and humidity.
• Air drying: Exposing timber to natural air circulation.

Timber Defects

• Four natural timber defects:
• Knots: Formations where branches once grew, causing potential weakness.
• Shakes: Separations or cracks in the grain of the wood.
• Splits: Cracks extending along the grain.
• Wane: Missing wood on the edges of the timber.

Fits and Clearances

• Two types of fits and clearances:
• Clearance fit: One part fits loosely inside another, resulting in a gap between them.
• Interference fit: One part is larger than the other, requiring force to assemble them, resulting in a tight fit.

Gauge Functions and Types

• Taper gauges: Measuring the taper of a workpiece.
• Limit gauges: Checking if a component falls within specified tolerances.
• Form gauges: Testing the shape and profile of a workpiece.
• Thread gauges: Inspecting the size and pitch of threads.
• Four types of datums:
• Feature datum: A specific surface or feature on the component.
• Primary datum: A more important feature.
• Secondary datum: A less important reference feature.
• Tertiary datum: A less significant feature.

Test your knowledge on the hazards associated with welding shops and the various welding techniques. This quiz covers essential safety aspects like electric shock, fire risks, and harmful fumes, as well as methods such as gas welding. Improve your understanding of welding safety and techniques today!