Chapter II: Introduction

The constantly increasing use of gas-engines in the last decade has led to the invention of a great number of types, the operation and care of which necessitate a special practical knowledge that is not exacted by other motors, such as steam-engines.

Explosion-engines, driven by illuminating-gas, producer-gas, oil, benzin, alcohol and the like, exact much more care in their operation and adjustment than steam-engines. Indeed, steam-engines are regularly subjected to comparatively low pressures. The temperature in the cylinders, moreover, is moderate.

On the other hand, the explosion-motor is irregularly subjected to high and low pressures. The temperature of the gases at the moment of explosion is exceedingly high. It is consequently necessary to resort to artificial means for cooling the cylinder; and the manner in which this cooling is effected has a very great influence on the operation of the motor. If the cooling be effected too rapidly, the quantity of gas consumed is considerably increased; if the cooling be effected too slowly, the motor parts will quickly deteriorate.

In order to reduce the gas consumption to a minimum, a matter which is particularly important when the motor is driven by street-gas, the explosive mixture is compressed before ignition. Only if all the parts are built with joints absolutely gas-tight is it possible to obtain this compression. The slightest leakage past the valves or around the piston will sensibly increase the consumption.

The mixture should be exploded at the exact moment the piston starts on its working stroke. If ignition occurs too soon or too late, the result will be a marked diminution in the useful effect produced by the expansion of the gas. All ignition devices are composed of delicate parts, which cannot be too well cared for.

It follows from what has thus far been said that the causes of perturbation are more numerous in a gas than in a steam engine; that with a gas-engine, improper care will lead to a much greater increase in consumption than with a steam-engine, and will cause a waste in power which would hardly be appreciable in steam-engines, whether their joints be tight or not.

It is the purpose of this manual to indicate the more elementary precautions to be taken in the care of an engine operating under normal conditions, and to explain how repairs should be made to remedy the injuries caused by accidents. Engines which are of less than 200 horse-power and which are widely used in a small way will be primarily considered. In another work the author will discuss more powerful engines.

Before considering the choice, installation, and operation of a gas-engine, it will be of interest to ascertain the relative cost of different kinds of motive power. Disregarding special reasons which may favor the one or the other method of generating power, the net cost per horse-power hour will be considered in each case in order to show which is the least expensive method of generating power in ordinary circumstances.

R. E. MATHOT.

MARCH, 1905.

TABLE OF CONTENTS

CHAPTER I
PAGE
MOTIVE POWER AND COST OF INSTALLATION 17

CHAPTER II

SELECTION OF AN ENGINE

The Otto Cycle.--The First Period.--The Second Period.--The Third
Period.--The Fourth Period.--Valve Mechanism.--Ignition.--
Incandescent Tubes.--Electric Ignition.--Electric Ignition by
Battery and Induction-Coil.--Ignition by Magnetos.--The Piston.--
Arrangement of the Cylinder.--The Frame.--Fly-Wheels.--Straight
and Curved Spoke Fly-Wheels.--The Crank-Shaft.--Cams, Rollers,
etc.--Bearings.--Steadiness.--Governors.--Vertical Engines.--
Power of an Engine.--Automatic Starting 21

CHAPTER III

THE INSTALLATION OF AN ENGINE

Location.--Gas-Pipes.--Dry Meters.--Wet Meters.--Anti-Pulsators,
Bags, Pressure-Regulators.--Precautions.--Air Suction.--
Exhaust.--Legal Authorization 69

CHAPTER IV

FOUNDATION AND EXHAUST

The Foundation Materials.--Vibration.--Air Vibration, etc.--
Exhaust Noises 87

CHAPTER V

WATER CIRCULATION

Running Water.--Water-Tanks.--Coolers 98

CHAPTER VI

LUBRICATION

Quality of Oils.--Types of Lubricators 111

CHAPTER VII

CONDITIONS OF PERFECT OPERATION

General Care.--Lubrication.--Tightness of the Cylinder.--
Valve-Regrinding.--Bearings.--Crosshead.--Governor.--Joints.--
Water Circulation.--Adjustment 121

CHAPTER VIII

HOW TO START AN ENGINE.--PRELIMINARY PRECAUTIONS

Care during Operation.--Stopping the Engine 128

CHAPTER IX

PERTURBATIONS IN THE OPERATION OF ENGINES AND
THEIR REMEDY

Difficulties in Starting.--Faulty Compression.--Pressure of Water
in the Cylinder.--Imperfect Ignition.--Electric Ignition by
Battery or Magneto.--Premature Ignition.--Untimely
Detonations.--Retarded Explosions.--Lost Motion in Moving
Parts.--Overheated Bearings.--Overheating of the Cylinder.--
Overheating of the Piston.--Smoke arising from the Cylinder.--
Back Pressure to the Exhaust.--Sudden Stops 134

CHAPTER X

PRODUCER-GAS ENGINES

High Compression.--Cooling.--Premature Ignition.--The Governing
of Engines 153

CHAPTER XI

PRODUCER-GAS

Street-Gas.--Composition of Producer-Gases.--Symptoms of
Asphyxiation.--Gradual, Rapid Asphyxiation.--Slow, Chronic
Asphyxiation.--First Aid in Cases of Carbon Monoxide
Poisoning.--Sylvester Method.--Pacini Method.--Impurities of
the Gases 165

CHAPTER XII

PRESSURE GAS-PRODUCERS

Dowson Producer.--Generators.--Air-Blast.--Blowers.--Fans.--
Compressors.--Exhausters.--Washing and Purifying.--
Gas-Holder.--Lignite and Peat Producers.--Distilling-Producers.--
Producers Using Wood Waste, Sawdust, and the like.--
Combustion-Generators.--Inverted Combustion 174

CHAPTER XIII

SUCTION GAS-PRODUCERS

Advantages.--Qualities of Fuel.--General Arrangement.--
Generator.--Cylindrical Body.--Refractory Lining.--Grate and
Support for the Lining.--Ash-pit.--Charging-Box.--
Slide-Valve.--Cock.--Feed-Hopper.--Connection of Parts.--Air
Supply.--Vaporizer.--Preheaters.--Internal Vaporizers.--
External Vaporizers.--Tubular Vaporizers.--Partition
Vaporizers.--Operation of the Vaporizers.--Air-Heaters.--
Dust-Collectors.--Cooler, Washer, Scrubber.--Purifying
Apparatus.--Gas-Holders.--Drier.--Pipes.--Purifying-Brush.--
Conditions of Perfect Operation of Gas-Producers.--
Workmanship and System.--Generator.--Vaporizer.--Scrubber.--
Assembling the Plant.--Fuel.--How to Keep the Plant in Good
Condition.--Care of the Apparatus.--Starting the Fire for the
Gas-Producer.--Starting the Engine.--Care of the Generator
during Operation.--Stoppages and Cleaning 199

CHAPTER XIV

OIL AND VOLATILE HYDROCARBON ENGINES

Oil-Engines.--Volatile Hydrocarbon Engines.--Comparative Costs.--
Tests of High-Speed Engines.--The Manograph.--The Continuous
Explosion-Recorder for High-Speed Engines.--Records 264

CHAPTER XV

THE SELECTION OF AN ENGINE

The Duty of a Consulting Engineer.--Specifications.--Testing the
Plant.--Explosion-Recorder for Industrial Engines.--Analysis of
the Gases.--Witz Calorimeter.--Maintenance of Plants.--Test of
Stockport Gas-Engine with Dowson Pressure Gas-Producer.--Test of
a Winterthur Engine.--Test of a Winterthur Producer-Gas
Engine.--Test of a Deutz Producer-Gas Engine and Suction
Gas-Producer.--Test of a 200-H.P. Deutz Suction Gas-Producer and
Engine 279