An Improved Floating Dry-dock and Vessel-cleaner.
Year: 1896

page_text: Date of Application, 3rd Nov., 1896-Accepted, 2nd Jan., 1897
COMPLETE SPECIFICATION.
An Improved Floating Dry-dock and Vessel-cleaner.
I, MARK WORSNOP MARSDEN, of 432 Walnut Street, Philadelphia, County
of Philadelphia, State of Pennsylvania, United States of America, Mechanical
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 :-
My invention relates to a new and useful dry-dock and vessel-cleaning apparatus,
and consists in the mechanical construction of the same hereinafter fully set forth
and described.
The object of my invention is to provide a floating dry-dock and vessel-cleaning
apparatus, which may be transferred from place to place either by its own power
or by outside assistance, and which, in addition to performing the function of a
cleaning apparatus for removing barnacles and other foreign substances that have
accumulated upon the hulls of other vessels, can also fulfil the function of a dry-
dock to permit access to the underside of vessels for the purpose of repairing,
painting or otherwise operating below the water-line, without the necessity of
removing said vessels from the water. The frequent necessity of scraping, cleaning
and painting the hulls of vessels is well known on account of the constant
accumulation of barnacles and other substances which decrease the speed of the
vessel, increase the consumption of fuel, injure the plates by corrosion, prevent
accurate steering or handling of the vessel, and which in many ways act as a
detriment thereto.
The enormous expense and unavoidable danger of straining or fatally injuring
a vessel by the method of dry-docking now common (which consists in floating a
vessel into a basin, which is subsequently drained, so that the vessel will be
supported mainly upon keel-blocks) makes it desirable that a means be provided
which will reduce the expense or lessen the danger attending the present method
of dry-docking. To accomplish this end I have designed a floating dry-dock and
vessel-cleaning apparatus, which will not only require less expense to operate, but
by which there may be a very great saving of time and labour partially attributable
to the automatic machinery with which it is provided, but more directly attribu-
table to the novel construction and application of the dry-dock proper.
My invention is illustrated by the accompanying drawings in which
Figure 1 is a side elevation of my floating dry-dock and cleaner, showing the
normal floating position.
Figure 2 is a side elevation of my floating dry-dock and cleaner, the same being
partially submerged and in position to operate upon other floating vessels.
Figure 3 is a central longitudinal section of the floating dry-dock shown in
Figure 2, showing the cleaning mechanism in the operative position.
Figure 4 is a similar view illustrating my invention as applied to a vessel, and
performing the function of a dry-dock.
Figure 5 is a similar view of my invention in another position.
Figure 6 is an end elevation of my invention looking toward its bow, the said
figure being partly in section to reveal the internal construction.
Figure 7 is a view showing details of construction.

page_text: Figure 8 is a transverse sectional view taken on two different planes and
revealing the internal construction and arrangement of the hull of my invention.
Figure 9 is a vertical sectional view showing the mechanical construction of one
of the details of my invention, and
Figure 10 is a similar view showing the construction of another detail.
Similar letters refer to similar parts in all the figures.
A represents the hull of my invention, a is a rudder, a' is a screw, one or more
of which may be provided, and by which the vessel may be propelled. B, B are
casings extending longitudinally along each side of the hull so as to form a
substantially U-shaped space between the same (see Figure 6), into or through
which space the vessel to be operated upon may project or may be passed as herein-
after described. These casings B have by preference sufficient space within the
same to contain suitable machinery for operating the various parts of the dry-dock
and cleaner and at the same time afford plenty of room for the operators to work.
b, b are windows or ventilators, any number of which may be placed at desirable
points in the outer sides of said casings. The roofs of the casings B, B may be
utilized as decks, which may be provided with suitable rails and companion-ways b₁.
When the hull of the vessel is partially submerged as shown in Figure 2 for the
purpose of getting under the hull of another vessel, the upper portions of the said
side casings B are the only portions of the dry-dock and cleaner which are out of
water. It is therefore desirable that suitable ventilators and companion-ways
be located toward or at the upper ends of the said casings B, B so that they may
be utilized under all circumstances. C is the space between decks (Figure 8) in
which the machinery is carried, and in which the persons who operate the dry-dock
and cleaner may freely move. Supplemental floors or galleries may be provided
as desired within the same. This space C communicates with the space in the
casings B, B by preference. D, D are water-compartments in the lower part of
the hull. These compartments D, D extend along the central lower portion of the
hull, and are by preference divided into sections by means of transverse water-
tight bulk-heads d, d (see Figure 4). E, E are water-compartments in the sides
of the hull, and separated from the water-compartments D'by suitable water-tight
bulkheads e. The compartments E, E are also divided into sections by means of
transverse water-tight bulkheads e, e, (see Figure 2) substantially similar to the
bulkheads d, d. By flooding the compartments D the bull of the dry-dock and
vessel-cleaner will be caused to sink in the water to a level approximately
corresponding to the floor of the U-shaped space between the casings B, B.
D', D' represent suitable supply and drain pipes respectively for flooding or draining
the compartments D, D. By flooding the compartments E, E the vessel will be
caused to sink until all but the upper portions of the casings B, B are submerged.
E, E represent suitable supply and drain pipes respectively for flooding or
draining the compartments E, E. In operation it is only necessary to fill said
compartments D, D, E, E to a degree sufficient to sink the dry-dock and cleaner
to a depth where it can be moved under the hull of the vessel to be operated upon,
as shown in Figure 2, in which figure the bow of the vessel to be cleaned is
illustrated as at a point intermediate in the length of the space between the
casings B, B, that portion of the said vessel which is within the dry-dock having
been cleaned by the mechanism I now propose to describe, the remaining uncleaned
portion of the hull below the water-line being illustrated as covered with barnacles
and other foreign substances.
To accomplish the act of cleaning I provide scrapers or knives F located at
suitable points around the inner surface of the U-shaped space between the
casings B, B (see Figures 3 and 6). To the rear of each knife, and mounted by
preference on the same base which supports the knife, is a roller F', the upper
surface of said roller extending by preference into a plane above the plane
determined by the edge of the blade F. In the rear of said blades and at suitable
points between, the casings B are suitable brushes G, the bristles of which are by
preference formed of steel or some other suitable metal, said brushes being adapted

page_text: to be rotated by suitable machinery located within the working space within the
hull previously referred to. The driving mechanism may be connected to the
pulleys g, g or equivalent mechanism, through which medium the power may be
transferred to the said brushes G. As illustrated in detail in Figure 9, the brushes G
are by preference provided with suitable means for automatically causing the same
to advance or retract, and means whereby the same may be adjusted so as to be
raised or lowered, as hereinafter described in detail. A means also may be
provided to regulate the position of the knives F as illustrated in detail in Figure 10
and as hereinafter fully described.
In operation, the hull of the vessel to be cleaned is introduced into the U-shaped
space between the casings B, B as illustrated in Figure 2, the dry-dock and cleaner
having first been sunk to a proper position to permit it to be moved under the bull
of the vessel. As the dry-dock and cleaner passes under the said vessel, the edges
of the scrapers or knives F, F cut and break up the barnacles or other hard
substances which have formed upon the hull of the vessel operated upon (see Figure 3),
the rollers F to the rear of said knives preventing the hull of the vessel from
resting directly upon the edges of the knives or scrapers, which would endanger
the safety of the vessel by reason of the fact that the knives might cut and injure
the bolts, rivet connections or plates of the same, should direct connection be had.
That portion of the vessel which passes the knives F and rollers F is subsequently
reached by the brushes G, G which come in contact with the hull, scouring and
taking off the loosened pieces of barnacles and other substances and thoroughly
cleaning the vessel. As the dry-dock and cleaner is. passed under the vessel, the
knives F and brushes G are advanced or retracted either by manual power or by
automatic means to compensate for the varying curves in the hull of the said vessel
being operated upon. If desirable each brush G may be provided with separate
rollers G¹ (see Figure 3) for the purpose of taking the weight off the brush; it is
obvious, however, that the said roller G' should be located by preference in a plane
below the plane determined by the face of the brush, so that the said brush may
freely come in contact with the hull. Suitable adjusting means may be provided
to raise or lower the said rollers G' so that the pressure of the brushes against the
hull of the vessel may be varied as desired. If desirable one or more rollers G³
(sce detail view Figure 9) may be substituted in place of the separate rollers G', said
rollers G2 being adapted to be moved automatically with said brush mechanism, as
hereinafter fully described.
After a vessel has been thoroughly cleaned and it is desired to paint the same
below the water-line, or in case it is desired to repair the hull, the dry-dock is sunk
to the proper level and is moved under that part of the hull of the vessel where it
is desired to operate (see Figures 4 and 5). Previous to sinking the dry-dock,
however, the shape of the vessel should be approximately ascertained and suitable
form-sections H, H inserted into suitable slots or retaining spaces around the inner
face of the U-shaped space between the casings B, B and toward one or both ends
thereof. I desirable a suitable yielding packing, by preference pneumatic or
hydraulic tubes I, I, may be placed in suitable retaining spaces upon the upper
edges of the form sections H, H for the purpose of providing a yielding packing
to perfect the joint between the same and the sides of the vessel to be cleaned.
After the dry-dock and cleaner is moved under the vessel to the proper position by
forcing out or drawing off the water from the compartments D, D, E, E, or some
of them, the hull of the dry-dock and cleaner is raised until it causes the form
sections H, H or the packing I, I to press tightly against the hull of the vessel to
be operated upon. By this means a water-tight joint is formed. Water contained
around that portion of the vessel between the sections H, H at each end of the
U-shaped space between the casings may then be pumped out or may be permitted
flow through the pipes J, J (see Figures 3 and 5) into the water-compartments in
the hull, from which it may be subsequently emptied. By draining the space
between the scctions H, H above referred to, free access may be had to that
portion of the hull between said points and below the water-line, thus permitting
to

page_text: operators to repair, paint or otherwise work upon the same. K, K are suitable
man-holes provided on the inner sides of the casings B, B through which the
operators may pass to get into the space underneath the hull of the vessel to be
cleaned. In Figure 5 only one set of form-sections H, H is provided in the space
between the casings B, B inasmuch as the vessel to be operated upon only extends
partially through said space. In order that the water within the dry-dock may be
drawn off, a suitable dam L is provided at the opposite end of the U-shaped space
between the casings B, B (see Figures 5 and 7). By this means, in addition to the
form-sections H and packing I at the opposite end, the water is prevented from
running into the said U-shaped space as it is drawn off through the drain-pipes J, J.
Suitable ring-bolts M may be provided in the deck of the dry-dock for permitting
suitable stays N to be connected from the deck of the vessel operated upon and
the dry-dock (see Figure 4). When the dry-dock is utilized in connection with
vessels that may be top-heavy, the pressure of the contact of the said dry-dock
with the outside of the bull of the said vessel may be made by means of these
stays N instead of by lifting the vessel as previously indicated.
I shall now proceed to describe the detail views shown in Figures 9 and 10, iu
which both automatic and manual adjusting devices are shown to regulate the
position of the brushes G and the knives F. In Figure 9, O is a stem projecting
downwardly from the base of the brush G, O¹ is a feather spline between the said
stem and a revoluble bushing P so that rotary motion imparted to said bushing P
will be transmitted to the stem O which passes longitudinally through said bushing.
Qis a spring contained within the stem O. R is a plunger extending up into the
lower end of the said stem O and bearing against the lower end of the spring Q.
S is an adjusting screw, located below said plunger R and bearing against same.
The stein Q thus described, while free for longitudinal movement, revolves with the
said rotary bushing P. The action of the spring Q causes the said brush to press
against the side of the vessel, but does not prevent the same from yielding to any
desired degree dependent upon the character and size of the spring Q. In addition
thereto the adjusting screw S may be raised or lowered, thus causing the normal
position of the stem O to be raised or lowered to the desired degree. G³ are
rollers supported upon a suitable frame loosely surrounding the stem O and resting
upon the collar T thereon. These rollers G as previously described, are for the
purpose of preventing the brush from being crushed by the weight of the vessel,
the said rollers being also adapted to cause the stem O which supports the brush,
to recede as the diameter of the vessel increases, thus making it unnecessary for
the brush to perform that function.
In Figure 10, U is a base supporting the knife F and roller F. This base is
longitudinally movable in an adjustable casing V supported and moved by an
adjusting screw W. X is a spring within said casing V hearing against the
lower side of the base U so that the knife F aud roller F' may automatically
yield.
In Figure 3 is illustrated one means for revolving the brushes G. In said
figure is an electric motor. Power from said motor is transmitted to the
brushes G through the ordinary system of belts Y' and pulley Y. The character
of the motor and means of connection may be varied as desired without departing
from the spirit and scope of my invention,
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. A dry-dock and vessel-cleaner, comprising a hull, water-compartments in said
hull, casings along each side of the hull forming a U-shaped space, and transverse
form-sections at one or both ends of said U-shaped space between said casings,
substantially as described.
2. A dry-dock and vessel-cleaner, comprising a hull, water-compartments in said
bull, means for emptying or filling said compartments, casings along each side of

page_text: the hull forming a substantially U-shaped space, and form-sections and packings at
one or both ends of said U-shaped space between said casings, substantially as
described.
3. A dry-dock and vessel-cleaner, comprising a hull, water-compartments in said
hull, means for filling or emptying said compartments, casings along each side of
said hull, and form-sections supporting the yielding packings located at one or
both ends of the space between said casings, substantially as described.
4. A floating dry-dock and vessel-cleaner, comprising a hull, water-compartments
in said hull, ineans for filling or emptying said compartments, casings along each
side of the hull, form-sections and packings supported thereby, and recesses for
retaining said form-sections at each end of the space between the said casings, all
substantially as and for the purpose described.
5. A floating dry-dock and vessel-cleaner, comprising a hull, water-compartments
in said hull, means for filling or emptying said compartments, hollow casings along
each side of the hull, form-sections and hollow packing tubes resting thereon, and
means for supporting or retaining the same at each end of the space between said
casings, and means for draining the space between said sections and packings and
said casings, when said dry-dock is in place for operation under the hull of a
vessel.
6. A floating dry-dock provided with form-sections detachably held thereby,
and extending transversely with respect to an imaginary line extending fore and
aft through the hull, said form-sections engaging the bottom and sides of the
vessel operated upon and acting as a dam to prevent the passage of water,
substantially as described.
7. A dry-dock and vessel-cleaner, comprising a hull supporting casings along
each side thereof, means for partially submerging said dry-dock, and adjustable
scrapers or knives extending into the space between said casings, substantially as
and for the purpose specified.
8. A dry dock and vessel-cleaner, comprising a hull, water-compartments in
said hull, means for flooding or draining said compartments, hollow casings along
each side of said hull, said casings extending upwardly and forming a U-shaped
space between the same through which space the vessel to be operated upon passes
or is passed, longitudinally adjustable scrapers or knives extending into said space,
and rollers adjacent to said knives to prevent the same from coming in contact
directly with the hull of the vessel to be cleaned.
9. A dry-dock and vessel-cleaner, comprising a hull, water-compartments in said
hull, means for flooding or draining said compartments, hollow casings along each
side of said hull forming a substantially U-shaped space through which the vessel
to be operated upon passes or is passed, longitudinally adjustable scrapers or
knives, rollers to the rear of said knives projecting into a plane above the plane
determined by the edge of the knives adjacent thereto, and means for automatically
regulating the position of the knives and rollers, substantially as described.
10. A dry-dock and vessel-cleaner, comprising a hull, water-compartments
therein, means for flooding or draining said compartmenuts, hollow casings along
each side of said hull forming substantially a U-shaped space above said hull and
between said casings, revoluble brushes projecting into said U-shaped space, and
means for revolving said brushes, substantially as described.
11. A dry-dock and vessel-cleaner, comprising a hull, water-compartments.
therein, means for flooding or draining the same, hollow casings along each side of
said hull forming substantially a U-shaped space above said hull and between said
casings, longitudinally adjustable brushes revolubly mounted, and projecting into
said U-shaped space, and rollers adjacent to said brushes, all substantially as and
for the purpose specified.
12. A floating dry-dock and vessel-cleaner, comprising a hull, water-compart-
ments therein, means for flooding or draining said compartments, hollow casings
along each side of said hull forming a substantially U-shaped space above the
centre of said hull and between said casinge, longitudinally adjustable scrapers or

page_text: knives extending into said space, longitudinally adjustable rotary brushes
projecting into said space, and means for operating the same, substantially as
described.
13. In a dry-dock and vessel-cleaner, a hull having hollow casings extending
along the opposite sides thereof, separate water-compartments located along the
lower part of the hull, means for flooding and draining said compartments,
longitudinally adjustable scrapers or knives, and rotary: brushes, extending into
the space between the said casings, and means for operating the same, said means
being contained within the space C and the hollow casings, substantially as
described.
Dated this 3rd day of November 1806
D. YOUNG & Co.,
11 & 12 Southampton Buildings, London, W.C.,
Agents for the Applicant.