Autoclave for thermally treating very long rubbery hose products, and the like

An autoclave comprises a long upwardly open channel-shaped vessel, a gas and pressure resistant lid closing the vessel, means for actuating the lid for simultaneously closing and opening the autoclave along its entire length, the structure of the vessel being unitary and supported at a plurality of locations along its length for permitting heat promoted variations in length of the autoclave.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
This invention concerns equipment, generically coming within the category 
of the so-called "autoclaves", for the thermal treatment, in closed and 
pressurized surroundings, and generally with steam, of products and 
articles of vulcanizable elastomeric material, such as natural or 
synthetic rubber. More particularly, this invention concerns an autoclave 
of very extensive size, in given direction, for the treatment of rubber 
articles of corresponding great length, typically rubber or essentially 
rubber hose, produced in pieces with a length generally greater than 100 
meters. 
More specifically, this invention concerns a linear autoclave for the 
industrial uses described, and adapted to constitute an operative element 
or unit of a complete plant for the manufacture of pieces of hose, of 
great length, in natural or synthetic rubber, such a plant being the 
subject of another contemporaneous application by the same applicant, to 
whose context reference is herein made, for the better understanding of 
some of the technical and industrial features of this same invention. 
Moreover, the above mentioned use of this invention does not constitute a 
limitation of the use of the invention, in that the invention could find 
advantageous industrial uses in equivalent fields, for example for the 
formation of vulcanizable rubber tapes, destined to various uses, for 
example, for the winding and manufacture of shaped bodies with a 
non-uniform diameter, or other. 
2. Description of the Prior Art 
The construction and more particularly the use of autoclaves with a length 
which in practice has not been considered by the experts in the art until 
now, for the production and the treatment by vulcanization of 
substantially linear articles, of corresponding great length, provide the 
solution to technical problems and the observance of conditions which, 
although common to all autoclaves, are presented in a different way in the 
field of the industrial production considered by this invention. 
In fact, the autoclaves destined to operate in said field must avoid 
drawbacks and limitations resulting from the inevitably large dimensional 
variations due to temperature variations, their internal space must be 
accessible along their entire great length, because linear articles of 
corresponding great length cannot be introduced and removed "heat first" 
into the autoclave; the closing of the autoclave must be air tight along 
its entire length, and the movable components and in particular the lid 
closing the internal space of the autoclave, must be practically 
uninterrupted and susceptible to contemporaneous operation along the 
entire length. 
To these conditions must be added the characteristics of rapid and safe 
manoeuvrability for the introduction, treatment and removal of the 
articles to be vulcanized the whole so as not to endanger the autoclave 
complex, to assure the uniformity and regularity of the treatment at every 
point of the article, and to reduce to a minimum the times required for 
the handling and the operations necessarily occurring between the 
successive mechanization cycles, carried out in the autoclave itself. 
SUMMARY OF THE INVENTION 
With the aim of reaching these and other advantages, characteristics and 
possibilities of industrial production, the autoclave according to the 
invention, which in practice can be practically without limits in length, 
is essentially characterized by being made up of a rectilinear 
channel-shaped body, open along the top, provided with an essentially 
unitary lid, connected at a number of points distributed along the said 
length, to a corresponding number of means for mechanical support, 
raising, and reapplication of the lid itself, when opening the autoclave, 
said mechanical means being individually connected to operative means, in 
particular oleodynamic or pneumatic jacks, operating parallely or in 
synchronism, so as to make the said lid move equally at every point in 
order to obtain the opening and the closing of the autoclave. 
Preferably, these means are connected to devices for locking the lid in the 
closed position, these devices being preferably but not necessarily 
operated unitarily and synchronously. 
According to an advantageous complementary characteristic of the invention, 
the entire outline of the elongated opening of the body of the autoclave 
is connected to a strip or sealing means made up of a pipe of deformable 
material, into which a pneumatic pressure can be applied, causing swelling 
and the consequent tight adherence of the said strip to the opposite 
marginal areas of the said lid. According to a complementary 
characteristic of the invention, the inside of the said tubular strip or 
sealing means is connected to the inside of the autoclave space, in such a 
way that its swelling and therefore the activation of the airtight sealing 
system occurs directly after the application of steam under pressure into 
the autoclave itself. 
These and other more specific characteristics of the invention will be 
evident from the following detailed description of a preferred but not 
exclusive embodiment, with reference to the drawings;

DESCRIPTION OF THE PREFERRED EMBODIMENTS 
With particular reference to the figures of the drawing: in its whole and 
as schematically illustrated in FIG. 1, the autoclave comprises a 
channel-shaped body, indicated as 10, which is a unitary structure, for 
example produced by means of assembly and connection on site, by means of 
welding, of a number of components. This body 10 is closed at both 
extremities by means of heads 12 and 14 (drawn as a simple line in FIG. 1 
for the sake of simplicity, but obviously of any desired shape, for 
example round) but open at the top along its entire length. To this body a 
lid 16 is connected, also of a unitary structure, to close and seal the 
said opening. 
Given the great length and essentially unitary structure of the said body 
10, and the variations in temperature to which the autoclave is inevitably 
subjected, the said body 10 is supported at not more than one point, 
preferably in its central zone, by a suitable fixed support 18, whilst its 
weight is distributed equally, through its remaining parts, on a number of 
supports 20, schematically illustrated in FIG. 1 in the form of 
"trolleys", and constructed in such a way as to allow rectilinear 
movements of the said parts, resulting from the thermal expansion and 
contraction. The lid 16 is produced for example by means of a number of 
plates arranged side by side and welded and composed of a material, 
generally ferrous, possessing a coefficient of thermal expansion equal to 
that of the body 10, in such a way which the said lid, that heats and 
cools in the same way as the body, follows its dimensional variations. 
The fact that the autoclave is composed of a channel-shaped body open along 
its entire length, permits the placing of the articles by transporting 
them in a direction transversal to the said length (for example, by means 
of a number of bridge cranes operating in synchronism) occupying together 
a quite limited space, and without having to use trolleys (which in this 
case would have to be of excessive length) as is used traditionally for 
the loading and unloading from one end, in the known autoclaves. The 
internal transversal dimension of the body 10, the same or different to 
that illustrated in FIGS. 2 and 3, is obviously of a size to receive the 
article or, preferably, a number of articles to be treated together, of a 
predetermined section and transversal volume, without leaving excessive 
spare space, for obvious reasons of saving on the inevitably considerable 
quantity of steam which must be introduced into the autoclave itself, in 
the course of treatment. 
A critical condition for the use of an autoclave as described above, is 
that the lid 16 which has a unitary structure must be raised and moved, 
with times and movements at accordance, in a number of points distributed 
along its length. The opening and closing of the lid could be obtained by 
means of mechanisms of the type illustrated in FIGS. 2 and 3, or their 
equivalent. These mechanisms can include hinge systems for the raising of 
the lid to rotate around an axis parallel to one of the greater sides of 
the opening of the autoclave, and systems such as to assure that the said 
lid can be perfectly applied "flatwise" on to the surface 22 of the upper 
part of the said outline. The mechanical means which raise and reapply the 
said lid therefore comprise preferably joints or balanced suspension. 
In the example shown, the lid 16 can be moved away from the opening 24 of 
the channel-shaped body by means of lever and brace systems as illustrated 
in FIGS. 2 and 3, which are reproduced and distributed along the length of 
the autoclave at suitable intervals. Each mechanism includes for example 
an upper lever 26, one end of which is fixed at 28 to the lid 16, 
preferably above its longitudinal barycentric line, as well as fixed at 30 
to the head of a second carrying lever 32 fixed in its turn at 34 to a 
fixed point, which can however favour the thermal expansion of the lid 16, 
when it cannot be absorbed by the said levers and the said joints. The lid 
16 therefore carries out a combined movement of raising and translation 
for the complete uncovering of the opening 24, a movement which can be 
seen from FIGS. 2 and 3. 
The movements of the lever 26, for the raising of the lid, can be 
controlled by jacks 36, connected by means of suitable joints to the parts 
on which they act and react, and those of the carrying lever 32, which 
determine the lateral moving, by jacks 38, correspondingly connected by 
means of joints. The batteries of jacks 36 and 38 can be controlled in 
sequence, in order to obtain the desired sequence of movements, but all 
the jacks of each battery must be controlled in synchronism and phase, in 
order to obtain a movement of the lid 16, in its entirety, keeping 
parallel to itself. 
Another critical condition is that the lid 16 can be restrained at a number 
of points, preferably relatively close, to the profile of the opening 24, 
in order to be able to resist the considerable thrust applied at the same 
time to the said lid, by the pressure of the steam introduced into the 
autoclave. This restraint can by obtained for example by means of a number 
of opposed brackets 40 and 42, connected along the profile of the said 
opening, and of a shape such as to bestride both the marginal parts 16a 
and 16b of the lid 16, as well as the protruding edge 10a and 10b of the 
body 10, after a previous application of the lid on to the opening 24. 
These brackets are operated for example in their turn by jacks 44 and 46, 
also operated in synchronism along the length of the autoclave, by control 
means connected to suitable safety systems, for example, in such a way 
that the brackets can be moved towards their working position only after 
the completion of the application of the lid, and respectively they are 
withdrawn after the inside of the autoclave is totally reduced to 
atmospheric pressure. Similarly, other safety devices could prevent the 
activation of the jacks 36 and 38 for the raising and opening of the lid, 
until this latter is completely freed from the restraint imposed by the 
said brackets. 
According to another complementary characteristic of the invention, the 
airtight sealing between the applied lid and the profile of the opening 24 
of the autoclave, is assured by means of pneumatically reinflatable 
strips. As illustrated in FIGS. 4 and 5, these strips are made up of an 
essentially channel shaped body 50 placed in a packing groove 52 which 
runs without interruption along this profile. Obviously, when laying the 
said strip 50, suitable care should be taken in order to assure its 
perfect and complete insertion and so as to be uninterrupted along its 
length. 
A gas under pressure, preferably steam, is applied to this sealing strip, 
in order to take advantage of the availability of the pressurized steam, 
necessary for the service of the autoclave. The introduction of steam into 
the inside of the autoclave and the strip can be carried out by means of a 
double tube system, emerging to a number of points distributed along the 
length of the autoclave, in order to assure that uniformity of the 
pressure applied is rapidly reached. According to a particularly simple 
solution, the walls of the body 10 are provided with passages so as to 
form a number of pipes 60 (FIGS. 4 and 5) which connect the inside of the 
autoclave with the inside of the sealing strip 50, without excluding the 
possibility of an independent and preliminary application of pressure into 
the strip, to obtain the airtightness of the closing before the 
application of pressure into the autoclave. 
Similarly, considering the great volume of steam to be introduced into the 
autoclave, and the great length of the latter, the autoclave is provided 
with a number of steam outlets, distributed along its length. These 
outlets can be synchronously operated by means of electrically-operable 
valves or other, controlled by a central command. Obviously, modifications 
can be made within the scope of the invention as defined in the appended 
claims.