An Improved Method of and Apparatus for Raising and Floating Sunken Vessels.
Year: 1894

page_text: Date of Application, 26th Jan., 1894
Complete Specification Left, 19th Oct., 1894-Accepted, 24th Nov., 1894
PROVISIONAL SPECIFICATION.
An Improved Method of and Apparatus for Raising and Floating
Sunken Vessels.
We JAMES WILLIAM GRANT, Wrecker, and JOSEPH GRANT, Wrecker,
both of Tacoma, in the County of Pierce and State of Washington, United States
of America, do hereby declare the nature of this invention to be as follows:-
This invention relates to a method of and apparatus for raising sunken vessels, by
means of bags arranged in the vessel and adapted to be inflated to displace the
water in the hold.
The method consists in placing in the hull of the vessel perforated collapsible
bags, charging the same with a fluid under pressure to expand the bags to displace
the water permitting excess of fluid pressure to escape through the perforations,
and maintaining a supply of fluid to the bags.
The apparatus consists of one or a series of collapsible and perforated bags
connected with a fluid supply under pressure.
In the apparatus for raising sunken vessels, as heretofore constructed, collapsible
and air-tight bags were employed and when charged with air under a heavy pressure,
the bags expanded and invariably burst and were thus rendered entirely useless for
the purpose for which they were intended. In order to prevent, to a certain extent,
bursting of the bags the latter were provided with valves to allow air to escape, but
such valves are liable to get out of order and either prevent any escape of air, or
permit all the air in the bag to escape.
When an air-tight bag expands in a compartment of a vessel and strikes an
obstruction such as part of the cargo, then the expansion of the bag becomes
restricted and the bag cannot expand uniformly, and as no provision is made for
the free escape of the air at all times, the pressure of the incoming compressed air
will finally burst the wall of the bag and again permit the sea water to refill the
compartment.
In order to successfully raise and float the vessel and to avoid the above-
mentioned and other difficulties, we charge the bags and constantly supply the same
with a fluid under pressure slightly exceeding the weight of the water to be
displaced, and permit any excess of pressure to freely escape through the pores,
meshes or perforations of the bags.
The bags are preferably made in the shape of cylinders and of canvas or similar
material having a comparatively loose mesh, so that when a fluid is forced in the
bag and the latter expands, then as long as more air is forced in the bag under
pressure, part of the air can escape through the open meshes in the fabric forming
the bag. Other suitable material, however, may be employed for forming the bags,
but it is distinctly understood that the bags must not be air-tight, but must have
pores, perforations, or other openings, to permit air to escape after the bag is
inflated and expanded and more air is forced into the bag.
The bags in the collapsed state are placed in the hold of the vessel to be raised,
and the ends of the bags are connected with air supply pipes, extending upward to
connect with a suitable receiver floating on the surface of the water directly over
the vessel to be raised. This receiver is connected by a pipe with an air compressor
or other suitable machine for forcing a fluid (air) through the pipe into the receiver
so as to fill the same and keep the latter charged with the fluid under pressure.
When the collapsible perforated bags are placed in the hold of the vessel and are
filled with air under pressure, they commence to expand and displace the water
in the hold, the pressure of the air for expanding the bags being slightly in excess

page_text: of the weight of the water to be displaced. Any further incoming air from the
receiver will readily leak through the pores, meshes or perforations of the bag, so
that the latter is not subjected to a much higher pressure than that of the weight
of the displaced water, consequently the pressure on the walls of each bag is
approximately alike on both sides so that the bags are not liable to burst.
The receiver is of sufficient size to supply all the bags with the necessary amount
of air to completely fill the same and keep the same filled, until the sunken vessel
is raised and is floating on the surface of the water, and fastened to another vessel
or vessels for towing it to the shore or other place.
_ Dated this 26th day of January 1894.
COMPLETE SPECIFICATION.
An Improved Method of and Apparatus for Raising and Floating
Sunken Vessels.
We, JAMES WILLIAM GRANT, Wrecker, and JOSEPH GRANT, Wrecker,
both of Tacoma, in the County of Pierce, and State of Washington, United States
of America, 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 invention relates to a method of, and apparatus for, raising sunken vessels, by
means of bags arranged in the vessel and adapted to be inflated to displace the
water in the hold.
The object of the invention is to provide a new and improved method and
apparatus for raising and floating sunken vessels in a very simple and economical
manner and without danger of bursting the bags.
The method consists in placing in the hull of the vessel perforated collapsible bags,
charging the same with a fluid under pressure to expand the bags to displace the
water, permitting excess of fluid pressure to escape through the perforations, and
maintaining a supply of fluid to the bags.
The apparatus consists of one or a series of collapsible and perforated bags
connected with a fluid supply under pressure.
The invention also consists of certain parts and details, and combinations of the
same, as will be hereinafter described and then pointed out in the claims.
Reference is to be had to the accompanying drawing, forming a part of this
Specification, in which the figure is a side elevation of the improvement as applied
and with parts in section.
In the apparatus for raising sunken vessels, as heretofore constructed, collapsible
and air-tight bags were employed and when charged with air under a heavy pressure,
the bags expanded and invariably burst and were thus rendered entirely useless for
the purpose for which they were intended. In order to prevent, to a certain extent, the
bursting of the bags the latter were provided with valves to allow air to escape, but
such valves are liable to get out of order and either prevent any escape of air, or
permit all the air in the bag to escape.
When an air-tight bag expands in a compartment of a vessel and strikes an
obstruction such as part of the cargo, then the expansion of the bag becomes restricted
and the bag cannot expand uniformly, and as no provision is made for the free
escape of the air at all times, the pressure of the incoming compressed air will finally
burst the wall of the bag and again permit the sea water to refill the compartment.
In order to successfully raise and float the vessel and to avoid the above-
mentioned and other difficulties, we charge the bags and constantly supply the same

page_text: with a fluid under pressure slightly exceeding the weight of the water to be displaced,
and permit any excess of pressure to freely escape through the pores, meshes or
perforations of the bags.
The bags A are preferably made in the shape of cylinders and of canvas or similar
material having a comparatively loose mesh, so that when a fluid is forced in
the bag and the latter expands, then as long as more air is forced in the bag
under pressure, part of the air can escape through the open meshes in the
fabric forming the bag. Other suitable material however, may be employed for
forming the bags, but it is distinctly understood that the bags must not be air-tight,
but must have pores, perforations or other openings, to permit air to escape after
the bag is inflated and expanded and more air is forced into the bag.
The bags A in the collapsed state are placed in the hold of the vessel to be raised,
and the ends of the bags are connected with air supply pipes B, extending upward
to connect with a suitable receiver C, floating on the surface of the water directly
over the vessel to be raised, as illustrated in the drawing. This receiver C is con-
nected by a pipe D, with an air compressor E, or other suitable machine for forcing
a fluid (air) through the pipe D into the receiver C, so as to fill the same and keep
the latter charged with the fluid under pressure. The air compressor E is located
on a scow or other vessel F, floating on the water as indicated in the drawing.
When the collapsible perforated bags are placed in the hold of the vessel and are
filled with air under pressure, they commence to expand and displace the water in
the hold, the pressure of the air for expanding the bags being slightly in excess of
the weight of the water to be displaced. Any further incoming air from the
receiver C will readily leak through the pores, meshes or perforations of the bag, so
that the latter is not subjected to a much higher pressure than that of the weight
of the displaced water, consequently the pressure on the walls of each bag is
approximately alike on both sides so that the bags are not liable to burst.
The receiver C is of sufficient size to supply all the bags with the necessary
amount of air to completely fill the same and keep the same filled, until the sunken
vessel is raised and is floating on the surface of the water, and fastened to another
vessel or vessels for towing it to the shore or other place.
Having now particularly described and ascertained the nature of our said inven-
tion, and in what manner the same is to be performed, we declare that what
we claim is :-
1. The herein described method for raising and floating sunken vessels, consisting
in placing a perforated collapsible bag in the vessel to be raised, charging the bag
with a fluid under pressure to expand the same so as to displace the water in the
vessel, the perforations permitting excess of fluid to escape through the same, and
keeping the bag charged by constantly supplying the same with fluid under pressure,
substantially as shown and described.
2. An apparatus for raising and floating sunken vessels, provided with collapsible
and perforated bags connected with a fluid supply under pressure, substantially as
shown and described.
3. An apparatus for raising and floating sunken vessels, comprising a floating
receiver connected with an air compressor, pipes leading from the said receiver, and
collapsible and perforated bags connected with the said pipes and adapted to be
placed in the hold of the vessel, substantially as shown and described.
Dated this 19th day of October 1801
A. M. & WM. CLARK,
53, Chancery Lane, London, Chartered Patent Agents.