Improved Apparatus for Impregnating Wood with Liquids.
Year: 1895

page_text: Date of Application, 9th May, 1895-Accepted, 15th June, 1895
Improved Apparatus for Impregnating Wood with Liquids.
I, LOUIS MATHIEU GUSIAVE JEAN LOUSTALOT, of 95 Boulevard Beau-
maichais, Paris in the Republic of France, 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
This invention relates to apparatus designed for the impregnation and saturation
of all kinds of wood with liquids.
It is known that wood when used for certain purposes for instance as sleepers on
railways, or as telegraph-posts and the like, must be impregnated with certain
antiseptic or other solutions Creosote 18 actually often used for the saturation
of wood but the impregnating or injecting processes have heretofore given
unsatisfactory results because they allow of impregnating or injecting the soft part
only of the wood whereas the heart or inner core has never been penetrated; this
fact results in a great inconvenience since after a time the heart or inner core
becomes rotten and there remains in the end nothing but the soft wood or outer
layer.
This defect is often observed for instance in railway sleepers, the heart or
iuner core becoming rotten or enten by insects so that the sleeper e transformed
into a hollow cylinder or rather into a bored cylinder without consistence, and
the wood screws which serve for fixing the rails upon the sleepers no longer retain
their hold.
The object of this invention is to provide an improved process and apparatus for
the injection and saturation of all sorts and species of wood by any solution or
liquid by which process the solutious or liquids are injected not only into the sappy
or outer part of the wood but also to the heart or inner core of the wood.
In order to rendor the following description as clear as possible I have repre-
sented in the accompanying diawings, as an example only, such improved apparatus
by which I effect the injection of the liquid into the wood.
In the said drawings
Figure 1 is a longitudinal section of the apparatus,
Figure 2 is an end view of the same partly in section
Figure 3 represents the arrangement adopted for the assemblage of several
apparatus for the purpose of treating pieces of wood of great length.
Figures 4, 5 and 6 represent in detail a closing device for each cell of the
apparatus which allows of the cmission of the single door represented in Figure 2.
Figures 7, 8 and 9 refer to a modified constructional form of the apparatus in
which the cells are replaced by tubes.
The method of operation is as follows
After the pieces of wood-have been cut down to the desued dimension according
to the purpose in view, they are inserted into a boiler A, Figure 1, after the
insertion of the wood the boiler is hermetically closed and steam or other suitable
hot fluid is then passed into the spaco lying between the cylindrical jacket C and
the boiler A. At the same time I produce a considerable vacuum in the interior
of the boiler A in which the wood is contained.
1 conduct the operation in such a manner as to gradually increase the temperature
of the wood and so as to attain after a certain time has elapsed, a temperature of
about 40 degrees Centigrade which 18 however not limited at this point but
obviously depends upon the nature, the density and other qualities of the wood under
treatment, also upon its degree of dryness.

page_text: Under the influence of the vacuum and of said increase of temperature,
distillation commences in the wood, and the more volatile acids leave the same,
thereby opening at the same time the cells or pores of the wood.
After having carried on this treatment during a certain tunc I abruptly inject
into the boiler A creosote under high pressure, raised or not to a certain
temperature.
The creosote thus injected and intensely compressed, enters the wood and, owing
to the porosity imparted to the latter by the preparatory work, is enabled to
thoroughly penetrate the same in a very short time and to completely impregnate
the heart or inner core of the wood.
When this treatment is finished the creosote is discharged from the central
cylinder, and the wood taken out, which after then having been dried, is ready
for use.
What has been said with regard to the creosote is of course applicable to any
other antiseptic solutions that may be employed, the same also applies to solutions
serving to impart to the wood not preservative qualities but for instance particular
colours o combustible properties and generally speaking the apparatus 18
applicable as stated herembefore for injecting into wood of all kinds and species,
any liquid or solution.
In the first part of this process the vacuum and the temperature are to be
combined in such a manner that the latter is sufficiently low so as not to destroy
or injure the wood, while nevertheless allowing of the commencement of the
distillation necessary for opening the pores sufficiently, to facilitate the entrance
of liquid during the second part of the operation
The boiler, as has been stated herembefore, substantially comprises A
quadrangular body A provided at its front part with a closing door B arranged on
hinges (6). In order to produce a hermetic closure by the aid of the door, the
latter is provided with notches (c) which-when the door is closed-are engaged by
articulated bolting rods provided with thumb nuts I do not claim this method of
closing by bolts, which is of current use in the industry.
Around the boiler A is arranged a cylindrical jacket C; in the spuce between
the jacket and the boiler the steam serving for the heating enters
At D 19
arranged the entrance orifice for the steam, the condensing water being collected
by the outlet pipe E
The boiler A which is to be subjected to very high pressures during the process
of injection, 18 arranged in such a manner as not to burst under this pressure and
for this purpose the same is provided with a series of internal partitious integral
with the wall of the boiler, the latter is for facilitating its manufacture composed
of two pieces united by means of two flauges G. The partitions F forming a series
of cells are provided with small holes (f) in their partition walls, allowing of a
free circulation of the liquid through all chambers of the boiler.
The operation is conducted in the following manner :
;
First the wood is brought into the compartments F, then after the front door
has been closed and bolted as herein before indicated, steam is introduced between
the jacket C and the boiler. When the desired temperature has been reached, the
boiler A is placed in communication with a vacuum pump through the medium of
the pipe (a) so as to extract as much as possible of the air contained in the boiler
this being done the rock II 18 suddenly opened to place the boiler in communication
with a liquid compressing apparatus. In proportion as the liquid to be injected
euters the boiler, the non-utilized surplus of liquid escapes through the cock H¹ so
that a liquid cui rent is produced in the boiler, which traverses the wood; this is
done because it has been found that by thus producing a current of liquid the wood
18 more completely injected and more thoroughly saturated.
At the exit orifice of the cock H' a pressure releasing device or also a valve
regulatable at will, is interposed, in order to regulate the pressure and to adjust
the same in any other apparatus that may be connected in series with the first one.
When the injection is completed which will be indicated by experience according

page_text: to the time during which the injection has lasted, the circulation of liquid through
the boiler is stopped, the liquid contamed in the latter is discharged and the frout
door is then opened, the injected wood is thereupon removed; the boiler may
then be ro-filled with a new charge of wood to be injected and the operation
recommenced.
In case pieces of very great length are to be injected, I unite as indicated in
Figure 3 a series of boilers A with one another, taking care that the steam
jackets C communicate with one another; the action of the apparatus is absolutely
identical with that herein before described.
Considering the great pressure required in the boilor A, I may instead of using
only one single door B-provide ench of the cells or compartments with a special
separate door arranged as indicated in detail in Figures 4, 5 and 6
At the front of each cell two articulated levers L are arranged on the one hand
upon the wall of the cell at L' and on the other hand upon an interior door M
and L. In its vertical position this door bears upon an iudia-rubber ledge placed
internally against the flange N of the cell. It is thus seen that owing to the
intelio pressure of the cell, the door M will apply itself exactly against the
Blange N, and will compress the indiarubber ledge O and thus form a hormetic
joint. The greater the pressure the tighter the joint will become.
In order to open the door it is sufficient as indicated in the upper part of Figure
to push it back when the pressure in the cell has censed to exist, the door then
turns and falls into a recess Pai ranged in the bottom of the cell.
Figures and 6 show in plan and elevation respectively a cell or compartment
closed by means of a door of the construction above described. As will be seen,
this door or closing device, as described can only resist a pressure exerted from
inside of the boiler and would be useless when the vacuum is to be produced; in
order now to remedy this inconvenience and to allow of its also resisting outer
pressures complete my closing device by means of a wooden bar X of a length
intermediate of the length of the sides of the compartments or cells and the
diagonal line of the same so that the door is held in place when the bar presents
itself horizontally or vertically (Figure 4) while on the other hand it is free to
open when the said bar X lies in diection of the diagonal line (Figure 6).
In certain cases it may be useful to replace the cells of the boiler by a series of
tubes 1 completely independent of one another as indicated in Figures 7, 8 and 9
These tubes, which may be circular or of any other suitable cross section are
placed in the interior of a box B which constitutes the vessel in which the hot
fluid that serves to raise the temperature enculates. Each of the tubes 1 18
composed of
1st. A cylindrical portion and
2nd. Two fastening or attaching devices 2, which latter may be opposite each
other analogous to the breech blocks of guns, or with hinge joint or bolt fastening.
In certain cases instead of using two attaching devices, namely one at each
extremity of the tube-one of the tube-extremnities may be fixed.
The arrangement of the tubes allowing of the manipulation of the apparatus 18
then as follows
1. A series or continuity of tubes for filling and emptying comprises:
A general conduit 4, communicating with the upper and lower reservoirs cou-
taining the antiseptic liquids, by means of the valves or plugs 5 and 6
Secondary conduits 7 which communicate with the general conduit by means of
the válves or plugs 8 and with the injection tubes by means of the tubular
connections 9.
2. A series or continuity of tubes for the injection under high pressure,
comprising:
A general conduit 10 communicating with the accumulators or with the injection
pumps.
Valves or plugs 11 serve for producing communication of the general conduit 10
with the secondary filling conduits 7.

page_text: 3. A series or continuity of tubes for the vacuum, comprising a general
conduit 12 which communicates with the vacuum vessel or with the vacuum pumps
by means of valves or plugs 13 and 14.
Secondary conduits 15 which are connected to the injection tubes by means of
the tubular connections or the valves or plugs 16; and to the general conduit by
means of the valves or plugs 17.
4. A series or continuity of tubes for the compressed air, consisting of:
A general condunt 18 communicating with the compressed an reservoir or with
the compression pumps by means of the valves or plugs 19 and 20.
Valves or plugs 21 which connect the general conduit 18 with the secondary
conduits 15
The operation of the valves or plugs 17 and 21 allows of utilizing the same
conduits 15 for the vacuum and for the compressed air.
The blocks or pieces of wood cut down to suitable dimensions according to the
uses to which they are to be put, are introduced into the tubes 1, aud the doors
thereof closed. The operator then opens the valve or plug 17 of the vacuum
corresponding to the horizontal series of tubes charged with wood to be injected.
As soon as the vacuum is sufficient in the tubes and the heating considered suitable
for the purpose, the valve or plug 6 01 5 is opened, according as one receives the
liquid of the charging reservous or of the lower eser vous, and then the valve or
plug 8 is opened corresponding to the series of tubes charged with wood.
As soon as the tubes are filled, the vacuum and filling valves or plugs are closed
and the valve or plug 11 for the liquid under high pressure 18 opened Under the
action of the accumulator the liquid abruptly penetrates the pores of the wood and
gradually enter the heart or inner core of the same.
When the injection is considered to be completed the valve or plug 11 19 closed
and the valves or plugs 8 and 6 of the battery of empty ng tubes are opened;
one likewise opens the valves on plugs 20 and 21 of the compressed-air conduit.
The compressed air acting under high pressure upon the liquid contamed in the
tubes forces the latter to rapidly leave, and dives it through the general series o1
continuity of tubes 4 to the upper reservoirs The opciation is now finished,
the valves or plugs are then closed and the doors opened, it remains only to take
out the injected pieces of wood, which may then at once be replaced by others
which have not yet been injected This may be done by hand or mechanically.
Figure 1 shows the possibility of increasing the length of the tubes for the
injection of pieces of wood of any length, the principle is the same as that shown
in Figure 3
In order to facilitate the introduction of the pieces of wood into the apparatus―
be it composed of a cell-boiler or of a series of tubes-and in order to likewise
facilitate the removal of the pieces of wood after they have been injected, I may
mount the apparatus upon trummious so as to enable it to oscillate, the placing in
position of the pieces of wood being effected when the front part of the apparatus
is at the top of its course, and the removal of the pieces of wood taking place
without mechanical work when the iront part of the apparatus is at the bottom of
its course that is to say inclined toward the ground. In this latter position, in
fact, the pieces of wood become displaced automatically owing to then weight.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, declare that what I
claim 18.-
1 An improved process of injecting and saturating wood of all sorts and species
by means of solutions or liquids, according to which the wood-previously ent
down to the desired dimensions-is placed into a hermetically closed receptacle,
capable of being heated by any suitable means, the wood, thus arranged being
first aised to a certain temperature then subjected to the action of a vacuum
produced in the receptacle; this double operation having for its purpose to open
the pores of the wood which latter is immediately afterwards, and without having

page_text: been again brought into contact with the outer air, subjected to the action of the
liquid applied for the impregnation, which liquid is injected under pressure into
the same receptacle.
2. For carrying out the process described in the first claim a boiler with a
double jacket, for the circulation of a hot fluid, formed by a series of partitions,
constituting cells, or compartments, into each of which is inserted one or several
pieces of wood the said cells or compartments communicating with one another by
means of orifices arranged in the partition walls.
3. In combination with the above claimed cells or compartments the arrange-
ment of articulated doors turning back into the interior of the cells and producing
in combination with the large main door of the boiler a hermetic closure of all
cells or compartments, as 18 herein before specified; the tight closure of the joints
between the doors and the front wall of the cells or compartments being effected
by means of india rubber rings.
4. In combination with the above claimed cell-boiler provided with doors, a
unique series or continuity of pipes permitting of the production of the vacuum
and of injecting under pressure any liquid desired to be applied for the impregnation
of the wood; the injection or the vacuum being propagated from cell to cell owing
to the holes arranged in the partition walls forming the colls or compartments as
bereinbefore specified.
5. The replacement of the interdependent cells or compartments by entirely
independent tubes, each of which bas a special series or continuity of tubes as
hereinbefore specified.
6. In combination with the above claimed boiler the arrangement of trunnions
enabling the boiler to oscillate for the purpose of facilitating the charging and
discharging of the pieces of wood, substantially as described."
Dated this 8th day of May 1895
HASELTINE, LAKE & Co.,
45, Southampton Buildings, Loudon, W.C., Agents for the Applicant.