Final answer
The neutral oxyacetylene torch with a 1-1.15:1 O₂:C2H₂ ratio is versatile, making it suitable for various applications Thus option d is the correct option.
Step-by-step explanation
The neutral oxyacetylene torch, with an O₂:C2H₂ ratio of 1-1.15:1, is indeed versatile in its applications. The balanced ratio ensures efficient combustion and temperature control during welding processes. Additionally, it is particularly effective for the welding of copper alloys. This is attributed to the neutral flame produced under the specified ratio, which prevents oxidation of copper and ensures a clean weld. The slightly carburizing nature of the flame promotes the formation of a reducing atmosphere, favorable for copper welding processes.
However, when it comes to welding steels, the neutral oxyacetylene torch can be considered harmful. Steels are susceptible to oxidation, and the neutral flame may not provide sufficient protection against it. In steel welding applications, an oxidizing flame is often preferred to ensure proper penetration and avoid contamination. Therefore, while the torch is versatile and beneficial for specific applications, it may not be suitable for all materials.
In summary, the final answer is (d) all of the above, acknowledging the neutral oxyacetylene torch's effectiveness with a balanced ratio for various applications, its suitability for welding copper alloys, but also recognizing its limitations and potential harm when applied to welding steels.
Therefore option d is the correct option.