Improvements in Lubricating Arrangements for Tail end Shafts of Marine Screw Propelling Engines.
Year: 1897

page_text: Date of Application, 8th May, 1897
Complete Specification Left, 8th Feb., 1898-Accepted; 30th Apr., 1898
PROVISIONAL SPECIFICATION.
Improvements in Lubricating Arrangements for Tail end Shafts of
Marine Screw Propelling Engines.
I, JOSHUA HYDE IRWIN, General Manager and Director of the North Eastern
Marine Engineering Company, Limited, South Dock, Sunderland, do hereby declare
the nature of this invention to be as follows:-
My invention consists of an arrangement whereby an adequate supply of oil may
be continuously applied to the tail end shaft of a screw propelling steam ship,
throughout almost the entire length of the stern tube, without access of water from
the outside and with the smallest possible waste of oil.
I introduce by preference a cast iron liner within the stern tube so that if, after
being somewhat worn, it be desired to renew it this may be done at less expense than
if the whole stern tube required to be renewed, but my invention may be applied to
the stern tube itself without bush. I run longitudinal grooves, straight or spiral,
along the shaft at the parts at which it bears, upon the stern tube, or I run these
grooves in the inside of the liner before mentioned, or in both shaft and liner, so as
to give facility for the flow of the oil to the whole bearing surface. I place at the
inside end of the stern tube or liner an ordinary stuffing box, so as to keep the oil.
from leakage into the ship, and at the outer end I place another stuffing box fitted
with self adjusting or adjustable packing arrangements, or I place an arrangement
forming the subject-matter of an application by me for Letters Patent of even date
herewith and numbered 11480 of 1897 so as effectually as possible to keep out
water and to keep the oil from leakage into the sea.
I arrange an oil tank, and a water tank each with closed top. I place these tanks
in communication with each other in such a way as that the internal pressure must
be equal in both. The water tank is fitted with small pipes, (or pipes with adjust-
able regulator to control the flow of water) leading to the sea, below the line of
immersion on each side of the ship. The pipes being too small or the
regulator too much closed to allow the sudden pitching of the ship, and consequent
momentary deep immersion, or the action of passing waves or depressions to affect
the level of the water in the water tank to any appreciable extent, but the opening
of the pipes being adequate to enable the water in the tank to take and maintain a
mean level corresponding closely to the immersion of the stern.
The oil tank I place at a desired height above the stern tube, so as to give a pressure
of oil within the stern tube very slightly in excess of the mean pressure of the water
outside. By the coupling together of these two tanks (the water tank and the oil
tank) I can at any time ensure that the pressure of oil within the stern tube does not
go beyond or fall short of the desired slight excess over the pressure of the water.
outside and thus adequate lubrication in ordinary circumstances is absolutely
secured, ingress of water is absolutely prevented and the smallest possible waste of
oil, with any arrangement of stuffing boxes or equivalent devices, is attained. I
prefer to make the height of the oil tank adjustable by any convenient means so as
to control at any time the supply of oil as desired. Of course the tanks may be fitted

page_text: with filling arrangements, pressure gauges, gauge glasses,
desired.
Dated this Seventh day of May 1897.
or other appliances
as
J. JAMESON,
Akenside Hill, Newcastle on Tyne, Agent for Applicant.
Improvements in Lubricating Arrangements for Tail end Shafts of
Marine Screw Propelling Engines.
I, JOSHUA HYDE IRWIN, General Manager and Director of the North Eastern
Marine Engineering Company, Limited, South Dock, Sunderland, 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:―
My invention consists of an arrangement whereby an adequate supply of oil may
be continuously applied to the tail end shaft of a screw propelling steam ship,
throughout almost the entire length of the stern tube, without access of water from
the outside and with the smallest possible waste of oil.
I introduce by preference a cast iron liner within the stern tube so that if, after
being somewhat worn, it be desired to renew it, this may be done at less expense than
if the whole stern tube required to be renewed, but my invention may be applied to
the stern tube itself without bush. I run longitudinal grooves, straight or spiral,
along the shaft at the parts at which it bears upon the stern tube, or I run these
grooves in the inside of the liner before mentioned, or in both shaft and liner, so as
to give facility for the flow of the oil to the whole bearing surface. I place at the
inside end of the stern tube or liner an ordinary stuffing box, so as to keep the oil
from leakage into the ship, and at the outer end I place another stuffing box fitted
with self adjusting or adjustable packing arrangements, or I place an arrangement
Sorming the subject-matter of an application by me for Letters Patent of even date
herewith and numbered 11486 of 1897 so as effectually as possible to keep out water
and to keep the oil from leakage into the sea.
I arrange an oil tank, and a water tank each with closed top. I place these tanks
in communication with each other in such a way as that the internal pressure must
be equal in both. The water tank is fitted with small pipes (or pipes with adjust-
able regulator to control the flow of water) leading to the sea, below the line of
immersion on either or each side of the ship. The pipes being too small or the
regulator too much closed to allow the sudden pitching of the ship, and consequent
momentary deep immersion, or the action of passing waves or depressions to affect
the level of the water in the water tank to any appreciable extent, but the opening
of the pipes being adequate to enable the water in the tank to take and maintain a
mean level corresponding closely to the immersion of the stern.
The oil tank I place at a desired height above the stern tube so as to give a pressure
cf oil within the stern tube very slightly in excess of the mean pressure of the water
outside. By the coupling together of these two tanks (the water tank and the oil
tank) I can at any time ensure that the pressure of oil within the stern tube does not
go beyond or fall short of the desired slight excess over the pressure of the water
outside; and thus adequate lubrication in ordinary circumstances is absolutely
secured, ingress of water is absolutely prevented and the smallest possible waste of
oil with any arrangement of stuffing boxes or equivalent devices is attained.
prefer to make the height of the oil tank adjustable by any convenient means so as
to control at any time the supply of oil as desired. Of course the tanks may be fitted
I

page_text: with filling arrangements, pressure gauges, gauge glasses, or other appliances as
desired.
In the drawing hereto attached A. is the water tank before referred to.
The top
of this tank is below the level of the sea even when the ship is light; so that if a
communication be made as by the pipe B from the sea to the lower part of this tank,
while the top of the tank is closed air tight, the effect will be to produce a pressure of
air within the tank corresponding to the difference in level between the water in the.
tank and the water in the sea. If the communication by the pipe B is very small
it will take a little time to produce this equilibrium but once established an almost
exact average equilibrium will be maintained by continual adjustment of influx and
eflux in accordance with varying conditions outside the ship. I use this pressure
to produce a corresponding pressure in the oil tank C that is to say I establish the
pressure in C by opening communication by the pipe D between the top of the
water tank and the top of the oil tank. In these circumstances, the air pressure in
both tanks being equal, if the level of the oil and the water in both tanks were the
same, and if both tanks communicate in any way with the sea, water would flow into
the oil tank, owing to the less specific gravity of the oil; and the level of the oil
would be thereby raised until equilibrium be established. If however the oil in
the oil tank be at a higher level than the water in the water tank and that the
difference of level be sufficient to more than compensate for the difference of specific
gravity of the oil and water then oil will flow out to the sea. And assuming the
circumstances to be the same the quantity of oil flowing will be greater the greater-
the difference of level. By making this oil tank adjustable as to its height above
a datum line, I can thus in similar circumstances adjust the flow of oil with any
desired degree of accuracy, if there be any passage at all for its escape; and I can
fill the stern tube with oil in such a way as to give to the contained oil (within limits)
an equal or any desired excess of pressure over the pressure of the water outside the
ship. For facility of working I may couple the oil tank to the stern tube by flexible
pipe or in any other convenient way.
The shaded portions of the two tanks indicate the water and the oil levels in each
and the arrows indicate the direction of flow in the various pipes. In order to
maintain with approximate exactness the desired excess of pressure in the oil tank
I may place within it an ordinary ball cock and float operated by any change in
level and fed from an oil cistern at higher level in any convenient place.. E' is the.
stern tube and F is the screw shaft.
"
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:
1st. The method or process of lubricating tail end shafts of screw propelling
engines, in such way as that a pressure of oil may be maintained within the stern-
tube, in a definite proportion.to, and at a slight adjustable excess over, the pressure
of the water outside, substantially as described.
2nd. The apparatus described and illustrated in the drawings.
1050.
J. JAMESON,
Akenside Hill, Newcastle on Tyne, Agent for Applicant.
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