Modern Machine-Shop Practice Part 272

=A perfect gas.=--What is Marriotte's law, or Boyle's law? Is steam a perfect gas? II. 411.

=Joule's equivalent.=--What is meant by the conversion of heat into work? What is Joule's equivalent? What is the mechanical equivalent of heat? II. 411.

=Indicator.=--What is a steam-engine indicator? II. 413.--How are indicators attached to an engine? II. 416.

=Indicator diagram.=--What are the names of the lines of a diagram? Why is a theoretical diagram not correct? II. 414.--What difference is there between the lines of a diagram of a condensing and those of a non-condensing engine? II. 415.--How is the expansion curve of a diagram tested? II. 417.

=Barometer.=--What is a barometer, and for what purpose is it used in connection with engine diagrams? II. 415.

=Horse-power by diagram.=--How do you calculate the horse-power of a steam engine from an indicator diagram? II. 418.

=Diagram vs. diagram.=--What difference is there between the diagram taken from one end and that taken from the other? II. 419.

=Consumption of steam by diagram.=--How would you calculate the consumption of steam or water of an engine from an indicator diagram?

II. 420.

=Steam line.=--What would a fall in the steam line of a diagram indicate? II. 421.

=Expansion curve.=--If the expansion curve is above the true expansion curve, what defect in the engine does that indicate? If the expansion curve falls too low, what does it indicate? II. 421.

=Valve lead by diagram.=--How would insufficient valve lead be shown on a diagram? II. 421.

=Excessive lead.=--How is excessive lead shown on a diagram? II. 421.

=Automatic cut-off.=--What is an automatic cut-off engine? What are the princ.i.p.al forms of automatic cut-off engines? II. 423.

=Releasing valve governor.=--What kinds of governors do engines with releasing valves have? II. 423.

=Corliss engine valves.=--How many valves does a Corliss engine have?

Explain the action of a Corliss valve gear. II. 423.

=Crab claw.=--What duty does the latch-link or crab-claw of a Corliss valve gear perform? II. 423.

=Valve trip.=--What means are employed in a Corliss engine to trip the admission valve? II. 423, 424.

=Point of cut-off.=--What determines the point of cut-off in a Corliss engine, and how does it do so? II. 424.

=Valve closing.=--What closes the valve in a Corliss engine? II. 424.

=Dash-pot.=--What is a dash-pot? What enables the dash-pot of a Corliss engine to work noiselessly? II. 424.--How is the amount of air cushion in the Corliss dash-pot regulated? II. 425.

=Shape of Corliss valve.=--What shape is a Corliss valve, and how far would its lap, as ordinarily constructed, carry the live steam period, leaving the cut-off mechanism out of the question? II. 426.

=High-speed engines.=--What is meant by the term high-speed engines? II.

427.

=Adjusting for load.=--What adjustments would you make if the engine had been running a very light load, and required to be adjusted for a heavy load? II. 427.

=High-speed governor.=--What cla.s.s of governor is generally used upon high-speed engines? II. 427.

=Varying the cut-off.=--What is the usual method of varying the point of cut-off on high-speed engines? II. 427.

=Wheel governor.=--State, in a general way, what a wheel governor consists of. II. 427.

=Even valve lead.=--Can the valve lead be kept equal when the point of cut-off is varied by shifting the eccentric across the shaft or crank-axle? II. 427.

=Marine engine.=--What forms of engine are used for marine purposes? II.

434.

=Inverted cylinder.=--What is an inverted cylinder engine? II. 434.

=Receiver.=--What is a receiver? II. 434, 453.

=Triple expansion.=--What is a triple-expansion engine? II. 436.

=Condensing engine.=--What is a condensing engine? II. 434.

=Compound engine.=--What is a compound engine? II. 434.

=Arranging compound cylinders.=--What are the two methods of arranging compound cylinders? II. 436.

=Condenser.=--What is a surface condenser? II. 440.

=Hot well.=--What is a hot well? II. 440.

=Steam condensation.=--Describe the means by which the steam is condensed after it is exhausted from the cylinder in a surface condensing engine, and state what becomes of the water of condensation and the injection, circulating, or condensing water. II. 440.

=Condenser tubes.=--How are condenser tubes made tight? II. 440.

=Blow-through valve.=--What is a blow-through valve? II. 440.

=Air pumps.=--What is a bucket air pump, and is it single or double acting? What is a piston air pump? What is a plunger air pump? What is a trunk air pump? When is a trunk air pump necessary? II. 441.

=Air-pump valves.=--Are a foot valve and a head valve always necessary to an air pump? II. 441.

=Pet c.o.c.k.=--Why are bucket pumps provided with a valve or pet c.o.c.k? II.

441.

=Bilge injection.=--What is a bilge injection? What fittings are necessary for a bilge injection? II. 441.

=Hot-well temperature.=--At what temperature is the water in the hot well usually kept? II. 441.

=Use of air chamber.=--What is an air vessel or air chamber used on a pump for? II. 441.

=Feed escape.=--What is a feed relief, or feed escape valve? II. 441.

=Checked boiler feed.=--What causes may act to stop the boiler feed? II.

441.