cameroon gce 2023 intermediate level Engineering Drawing 2
cameroon gce 2023 intermediate level Engineering Drawing 2
THEME: LATHE STOP
I-SET UP
The assembly drawing on page 4 represents an adjustable stop of a lathe machine (lathe stop).
II-DESCRIPTION AND FUNCTIONING
The lathe stop is made up of two basic parts, a top section!and a lower clamped section 2 which locks up to the
underside of tire lathe bed (not presented) when snugged down with a piece 13.
WORK REQUIRED
SECTION A
TECHNOLOGICAL STUDY (20 MARKS)
QUESTION 1: IDENTIFICATION AND FUNCTIONING OF PARTS (5 marks)
1.1 Give the name of pieces 11 and JJD.
1.2 State the function of piece 10.
1.3 State the function of piece 7_
1.4 Which type of materials do these hatchings in the table below represent?
(1 mark)
(1 mark)
(1 mark)
(2 marks)
QUESTION 2: DESIGNATION OF FASTENERS
2.1 Identify the fastener 8
2.2 Interpret the standard designation of the fastener 8: Screw CHc M4-8,
2.3 Identify the fastener 13
Select the standard designation of piece 13 , from the list below
(5 marks)
(1.25 marks)
(1.25 marks)
(1.25 marks)
2.4 (1.25 marks)
QUESTION 3: LINKAGES (5 marks)
3.1 Identify the type of link between pieces13 and 2.
3.2 Give the type of motion permitted by the link between pieces 3 and 4.
3.3 Tick three (3) characteristics of the link between the pieces 1 and 3.
(1 mark)
(1 mark)
(3 marks)
QUESTION 4: TOLERANCE AND FIT
The fit between piecej.and_4 is 030 //6/p5
+13
Given that, Hole 030 H6 = 030 o and Shaft 030 p5 = 030+ 22
4.1 Calculate the Maximum allowance.
4.2 Calculate the Minimum allowance.
4.3 Deduce from the calculations the type of fit.
4.4 Justify your answer.
(5 marks)
+35
(1.5 marks)
(1.5 marks)
(1 mark)
(1 mark)
QUESTION 5: FUNCTIONAL DIMENSION (5 marks)
5.1 Draw the chain of dimensions relative to the clearance ]A
5.2 Write down the equations of Maximum and Minimum clearances of ]A.
(2 marks)
(3 marks)