Question 2
2. (a) (i) Explain the term quenching.
(ii) Explain how to prevent cracks during quenching.
(b) (i) Sketch an anvil.
(ii) Label three parts of the sketch in 2(b)(i).
(c) List any three materials used for making soft hammer heads.
Observation
The candidates had difficulty answering parts (a) and (c). The required responses to these parts are:
(a) (i) Quenching is cooling hot or heated metals using either water, oil, sand,
ash or air.
(ii) To prevent cracks during quenching, long cylindrical workpieces should be
quenched vertically, flat workpieces should be quenched on edge and thick sections should enter the bath first. Cracking is also prevented by raising the temperature of the quenching medium.
(b) This part posed no difficulty to the candidates.
(c) Materials used for making soft hammer heads are: Aluminium, copper, raw hide, rubber and plastic.