Means for Preventing the Corrosion of the Propeller Shafts of Marine Engines.
Year: 1892

page_text: Date of Application, 30th Aug., 1892-Accented, 1st Oct., 1892
COMPLETE SPECIFICATION.
Means for Preventing the Corrosion of the Propeller Shafts of
Marine Engines.
1, EDWARD JORDAN, of 26, The Parade, Cardiff, in the County of Glamorgan,
Engineer, do hereby declare the nature of this invention and in what manner
the same is to be performed, to be particularly described and ascertained in and by
the following statement :-
The object of this invention is to provide a means for preventing the corrosive
action that generally takes place on propeller shafts at the point near the ends of
the brass sleeves. The ordinary tail-end or propeller shaft is usually cased with
two brass liners or sleeves, which are shrunk on to and firmly secured in metallic
contact with the shaft. The corner formed by the end of the sleeve and the shaft
has then been filled in with solder or red and white lead putty and marline has been
wolded round the shaft. This method has proved itself to be a very uncertain one
for its purpose, viz.; keeping the water away from the junction of shaft and sleeve.
The action of the sea-water upon the two metals is of a very corrosive nature, and
many accidents have resulted from the shaft breaking at this point in consequence
of its reduced sectional area. It is of common occurrence to find a deep groove cut
into and right around the shaft at the ends of the sleeves.
I therefore propose to
insulate each end of the brass sleeve by means of a water-tight insulator and thus
prevent the sea-water from getting between the two metals.
In order that my invention and the best means of carrying it into practical effect
may be thoroughly understood, I will now describe it and them in detail, referring
in so doing to the accompanying drawings which are to be taken as part of this
Specification and read therewith.
Fig. 1 is a side elevation of the tail-end of a propeller shaft shewing the sleeves
in position.
Fig. 2 is a sectional side elevation, on an enlarged scale, illustrating the process
of fixing.
In carrying my invention into effect, I make a recess a, in each end of the
eve that works in water, of sufficient depth to form an annular space around the
shaft. Into this recess I force, by pressure or otherwise, a suitable water-tight
insulator c, the material of which must be of such a nature that it shall have the
property of sticking both to the surfaces of the shaft and of the sleeve, and
sufficient consistency to hold itself firmly in place therein when in position. The
recess is, preferably, slightly larger in diameter at the inside than that at the outer
end, as illustrated in Fig. 2, so that when once the insulating material is set, it is
impossible for it to get adrift.
To force the insulating material c into the recess, 1 bore a hole in the outer
periphery of the sleeve, with which is connected the delivery d of a suitably formed
force pump, through which the material is pumped into the recess. A suitably formed
temporary ring or gland e is secured on to the shaft, close up to the sleeve, in order
to prevent the escape of the insulating material. A groove is turned in the ring
so as to allow of a projecting lip g of insulation protruding slightly beyond the end
of the sleeve. The insulating material which I propose to use is ordinary red and
white lead putty, but I do not confine myself to any particular composition inasmuch
as such materials as gutta-percha, asphaltum, pitch, or the like may be used. When
the material used melts at a low temperature, both shaft and sleeve are warmed
slightly to allow of the said being forced in.
The hole in the sleeve b through which the insulator is forced into the recess a is
preferably drilled above the inner end of the sleeve, and this as well as any other
holes which it may be deemed desirable to drill through the sleeve may be used for

page_text: the purpose of examining the condition of the shaft from time to time. For this
purpose the insulator is picked out, and after the examination has been completed,
the hole or holes are filled again.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
1. The combination of shaft end, sleeve end, annular groove cut therein and
insulator forced into the said groove, as set forth.
2. The combination of sleeve end, annular groove cut therein increasing in depth
in the direction of the sleeve, and an insulator of plastic material adapted to adhere
to the adjacent faces of shaft and sleeve, as set forth.
3. The improved means of preventing the access of water to the exposed end of
a sleeve and the adjacent surface of a propeller shaft, as set forth.
Dated this 30th day of August 1892.
PHILLIPS & LEIGH,
No. 22, Southampton Buildings, Chancery Lane, London, W.C.,
Agents for the Applicant.