Unit 10Unit 10

Welding, Brazing and CuttingWelding, Brazing and Cutting

Safety Principles

• General safety rules apply in ANY shop!

• Always observe all rules and procedures given by instructor

• Proper PPE should be worn at ALL TIMES– Jeans with no frays– Cotton long sleeved shirt– Close toed shoes/boots– Safety glasses and helmets

• Know where fire extinguishers are located in case of emergency

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Fire Extinguisher Classifications

Basic Welding Processes

• SMAW– Stick welding, use electrode to

melt metals– Typically the first process learned– Used for repair and maintenance– Popular in agricultural industry

• GMAW– Gas metal arc welding, use wire

fed through MIG gun– Relies on inert gas– More expensive– Superior results

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Basic Welding Processes

• GTAW– Gas tungsten arc welding

(another form of GMAW)– Slower– High quality welds

• OFW– Oxyfuel welding (fusion and

braze)– Electrode rod with base metal

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Electrode Rods and Wires

• Electrode Rods– Welding rod coated with flux– Different rods are available– Differ in tensile strength and flux

coating

• Electrode Wires– Packed in spools– Classified differently– Differ in tensile strength

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Electrode Rod

Electrode Wire

Welding Positions

Welding Positions

Welding Joints

Welding Joints

Oxyacetylene and Plasma Arc Cutting

• Oxyacetylene cutting-– Used on ferrous metal (steel)– Portable, useful in agricultural

industry

• Plasma cutting-– Stationary or handheld– Can be run by computer

• Plasma Arc SAFETY– Higher voltage– Never use in damp, wet areas– Use ear plugs/muffs– Proper PPE

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