2.1 Explain why a copper hammer should be used, and not a steel hammer, when hammer work is done where flammable vapours are present - NSC Agricultural Technology - Question 2 - 2016 - Paper 1

1. Increases Resistance to Corrosion: Copper enhances the corrosion resistance of the alloy.
2. Enhances Conductivity: The addition of copper improves the electrical and thermal conductivity of the alloy.
3. Hygienic Properties: Copper is naturally antimicrobial, making the alloys more hygienic for applications in environments that require cleanliness.

The process is called Annealing.

The metal cans must be coated with a thin tin layer primarily to prevent corrosion and to protect the contents from contamination. The tin acts as a barrier against moisture and harmful substances, ensuring the food remains safe for consumption.

1. Malleability: Tin can be easily worked into different shapes without breaking.
2. Corrosion Resistance: It resists oxidation and helps prevent rusting of the underlying metal.
3. Low Melting Point: Tin has a relatively low melting point, making it easy to work with during manufacturing processes.

1. Chromium: This element provides corrosion resistance.
2. Manganese: It improves the hardness and strength of the steel.
3. Nickel: Nickel enhances ductility and toughness.

1. Surface Preparation: Ensuring surfaces are clean and free of contaminants before applying adhesive.
2. Curing Conditions: Maintaining appropriate temperature and humidity during the curing process to obtain optimal bond strength.
3. Adhesive Layer Thickness: Applying an optimal thickness of adhesive to improve the contact area between the surfaces.

The substance added to resin to harden it is called a hardener or *catalyst.

Vesconite is suitable for marine applications because it is resistant to water and does not corrode, making it durable and reliable even when submerged or exposed to harsh marine environments.

1. Non-toxic: Vesconite does not contain any harmful substances such as asbestos or hazardous fibres.
2. Dust Generation: It does not generate harmful dust when machined, minimizing inhalation risks.
3. No Harmful Emissions: Machining Vesconite does not release toxic gases or smoke.

1. Higher Design Load Limit: Vesconite can support a higher load than white metal.
2. Reduced Wear: It exhibits better wear resistance, leading to longer service life.
3. Shrinkage and Expansion: Vesconite does not shrink or expand when exposed to moisture, maintaining dimensional stability.

1. Install Lightning Protectors: This helps to redirect lightning strikes safely to the ground.
2. Disconnect the Battery: Turning off the energiser and disconnecting the battery during thunderstorms prevents damage.

1. Mounting Height: Install the energiser at a height that is out of reach of potential thieves.
2. Secure Housing: Use a metal or concrete structure to lock the energiser, making it difficult to steal.

1. Size Specification: Signs must be at least 100 mm x 200 mm in size.
2. Color Requirements: The signs must have a black inscription on a yellow background.
3. Content Clarity: The warning must be clearly legible and include the phrase 'TAKE CARE - ELECTRIC FENCE!'

1. Increase Ground Stake Number: Install additional grounding spikes to improve conductivity.
2. Regular Maintenance: Ensure that the grounding system is regularly inspected and maintained to ensure efficient earthing.

1. Safety Positioning: The electric fence must be positioned so that the electrified wires are not accessible to pedestrians, reducing accident risks.
2. Signage Requirement: Display prominent warning signs to inform the public of the electric fence, ensuring visibility from a distance.