In the case of the internal combustion engine, the fuel (motor spirit or the heavier oils) is introduced directly into the engine and there vapourized and mixed with air so as to form an explosive mixture, so that all boilers, with the necessarily complicated systems of piping, etc., are done away with. It needs no imagination to understand the enormous saving of weight and space resulting from this elimination of the boiler, and of the room which it would occupy.
The latter-day demands for the provision of lighter and yet lighter, as well as space-saving propelling machinery for submarines, airships, aeroplanes, motor-cars, etc., especially during the war, have enormously stimulated the development of the engine which consumes its own fuel, and which is known as the internal combustion engine. A very wide field has thus been opened out for the exercise of the engineer’s ingenuity, and he has availed himself to the full of the opportunities thus created, never failing to rise to the occasion when fresh demands have been made upon him.
In these circumstances, it is not at all surprising to find that numerous firms have given considerable attention to the manufacture of the internal combustion class of engine, and many varieties, for a multiplicity of purposes, are upon the market. The limits of space effectively prevent my detailing the list of even the largest manufacturers; I will therefore content myself by referring to but one firm—Messrs. Vickers, Ltd.—who are now the largest manufacturers in the Kingdom. This progressive firm has grappled with the internal combustion engine problem from the earliest stages of the petrol engine to the latest forms of the heavy oil engine and its remarkable developments, and a large section of their establishment at Barrow-in-Furness is, and has long been, set aside exclusively for the design and manufacture of the heavy oil internal combustion engine. A very large staff of expert engineers has been selected for the work, while experiments with a view to improvements being effected in details are continually being conducted in the establishment. The result is that the development of this engine at the Barrow works has been attended with the highest success, a fact which is not widely known to the general public.
I take it as a great compliment that permission has been given me in this book to refer somewhat in detail to the achievements of Messrs. Vickers, Ltd., in this respect, for, hitherto, publicity in connection with this section of the firm’s operations has been strictly withheld. One of the latest and, it might well be said, the most important developments in connection with Messrs. Vickers’ activities, is the Vickers patent system of fuel injection, which enables an engine of the Diesel type (that is, using heavy oil) to be successfully run without the use of an air compressor for injecting the fuel into the engine. Before the introduction of this system, an air compressor, with its attendant complication and weight, had to be used for the introduction of the fuel into the engine. The elimination of this compressor has resulted in considerable economy in weight, space, and attendance, which, it will readily be seen, is a step in the right direction, whilst the efficiency of the engine has also been improved. The disadvantages attendant upon the use of the air compressor were early comprehended by Messrs. Vickers, and they have spared no efforts (nor expense) in developing the system which has led to its elimination.
The reader will require no knowledge of the subject to understand that the question of fuel consumption is one of the highest importance in any engine system, and, in regard to this point, Messrs. Vickers have made a special study, with the result that whilst the ordinary consumption in a Diesel engine with air compressor is ·41 lb. brake horse-power an hour (or 184 grammes par force de cheval), that firm have been able to reach the low figure of ·376 lbs. B.H.P. an hour (or ·170 grammes par force de cheval).
As one might expect, Messrs. Vickers, in bringing their engine to its present state of perfection, have, perforce, had a varied experience with fuel oils—and a considerable one, too,—for they have experimented with oils from all the well-known producing fields, and find that, under their system, practically any fuel oil which can be made to flow may be utilized in their engines—a fact which, in its importance, speaks for itself. The physical properties of the oils used by them have, naturally, differed very considerably. For instance, specific gravities have varied from ·810 to ·950 flash points from 100° Fahr., to upwards of 250° Fahr., whilst the viscosities, which the lay mind might well be excused for thinking of as “degrees of stickiness,” have varied from that of the ordinary kerosene (illuminating oil) to the thick asphaltic fuel oil which comes from Mexico. Readers may judge from this of the painstaking and difficult experiments that have been carried out in the Barrow works.
The advantages derivable from the use of the Vickers system could not, obviously, be withheld from general use, and the firm have upwards of twenty licensees now manufacturing internal combustion engines under their designs. This fact, though not familiar to “the man in the street,” is known in the manufacturing world.
900 B.H.P. LOW DUTY VICKERS ENGINE FOR OIL TANK VESSELS
