1. When is the solid die - nut used?
2. Name two (2) precautions to be taken before welding an empty petrol tank.
3. Give one (1) use for each of the following materials: (i) Foam (ii) carbon dioxide.
4. Explain why mild steel plates are not used for food cans. Name suitable material.
5. Name three (3) types of drilling machine used in an industry.
6. What did you understand by the helix of a twist drill?
Answer (1)
The solid die-nut is used for internal threading; precautions before welding an empty petrol tank include cleaning and purging it. Mild steel isn't used for food cans due to rust, while aluminum is suitable; types of drilling machines include bench, pillar, and radial arm drills. The helix of a twist drill aids in chip removal and enhances efficiency. ;
