Read the General Instructions (page 102).
Answer briefly any three, but not more than three, of the following
questions, and draw two, but not more than two, of the examples.
_Questions._
(_a._) Explain how the piston rings in Example 1, fig. 84, are made
so that the piston may work steam-tight in the cylinder. How are
these rings got into place? (8.)
(_b._) Give two views of a double riveted lap joint for boiler-plates.
(8.)
(_c._) Show by sketches how a wheel is fixed on a shaft by means of
a sunk key. Explain how the key may be withdrawn when it cannot be
driven from the point end. (8.)
(_d._) Give sketches showing the construction of a conical metal
lift or puppet valve and seating. (10.)
(_e._) With the aid of sketches explain how a piston rod is made to
work steam-tight through the end of the cylinder. (10.)
(_f._) Explain how the slotting machine ram of Example 8, fig. 85,
may be made to move up and down when at work. How is the length of
the stroke altered, and what is the object of the slotway in the
upper part of the ram? (10.)
_Examples to be drawn._
1. Piston for steam-engine. Draw and complete the two views shown
(fig. 84), the top half of the left-hand view to be in section.
Scale 1/2 size. (30.)
2. Plan and sectional elevation of a footstep bearing for an
upright shaft (fig. 83). Draw and complete these views. Scale
1/4 size. (35.)
3. Ram of slotting machine. Draw and complete the two elevations
shown (fig. 85). The tool-holders must be drawn in their proper
positions in the ram, and not separate as in the diagram. Scale
1/4 size. (35.)
[Illustration: FIGS. 83 AND 84.]
[Illustration: FIG. 85.]
* * * * *
First Stage or Elementary Examination. 1888.