Question 2
- (a) The sketch in Figure 1 is a furnace.
i. Identify the furnace.
ii. List the parts labelled W, X, Y and Z.
iii. State the function of the part labelled X
iv. What is the finished product of the furnace?
(b) State the function of the plug tap used in thread cutting.
(c) State the use of a hot set in forging process.
Observation
Candidates’ performance was not satisfactory. Candidates could not identify the type of furnace sketched in Figure 1, the finished product of the furnace and the function of the plug tap used in thread cutting.
Its solution is as follows:
(i) The type of furnace in figure 1 is an Electric Arc Furnace.
(ii) Listing the parts labelled:
W – Charging door
X – Carbon electrodes/ poles
Y – Pouring spout.
Z – Pivot / Trunion
(iii) Stating the function of part labeled X:
- To supply the required heat
(iv) The finished products of the furnace is a high –grade steel /alloy steel.
- Stating the function of the plug tap used in thread:
The function of the plug tap used in thread cutting is to complete the thread of through holes and blind holes, to form the full threads to be very close to the bottom of the hole.
- Stating the use of hot set in forging process:
- It is used for cutting hot bars.