Device for transferring products in plants for metallurgical treating of said products

An assembly for treating metal products is presented. The assembly includes a preheat furnace aligned with a reheat furnace. Cold products are initially heated in the preheat furnace and hot products bypass the preheat furnace. A material handling device is provided for a) transferring preheated products from an outlet of the preheat furnace to an inlet of the reheat furnace, and for b) transferring hot products from a point between the furnaces to the inlet of the reheat furnace. The material handling device includes a support extending between the outlet of the preheat furnace and the inlet of the reheat furnace for receiving preheated and hot products; and a displacement device located below the support means for lifting and translating preheated and hot products from the support means to the inlet of the reheating means.

FIELD OF THE INVENTION 
The present invention relates to a device for the treatment of iron and 
steel products in metallurgical furnaces. It relates more specifically to 
a transfer device allowing iron and steel products, such as billets, 
blooms, slabs and blanks, coming from a production site located upstream, 
especially of the continuous casting, rolling mill or storage yard type, 
to be loaded into reheat furnaces before they are used in a production 
site located downstream, particularly a hot-rolling mill. 
Another aspect of the invention also consists of a plant for the 
metallurgical treatment of iron and steel products, in which the 
geographical location of a first, so-called preheat furnace and of a 
second, so-called reheat furnace is optimized depending on the use of the 
transfer device according to the other aspect of the invention. 
BACKGROUND OF THE INVENTION 
For reasons of saving energy, of increasing productivity and of improving 
the quality, it is desired to charge reheat furnaces continuously with hot 
products coming directly from the continuous casting run. However, it may 
happen that the process is interrupted for various reasons--the continuous 
casting suspends its production or the latter is insufficient to feed the 
hot-rolling plant--and in this case, it is necessary either to provide 
cold products from a storage yard or periodically to supplement the 
production of hot products from the continuous casting run with the same 
cold products from the storage yard. 
Feeding the hot-rolling mill with a batch of products not having the same 
temperature causes quality problems in the outgoing products from the 
furnace. Overheating phenomena in hot products or underheating problems in 
cold products occur, causing energy losses and/or abnormal formation of 
scale. 
Plants exist which partly solve the abovementioned drawbacks. 
Thus, a first solution is known which consists in using a plant allowing 
intermediate furnace charging with hot products. A furnace is charged with 
cold products as soon as the furnace is started up. A furnace is charged 
with hot products via a side door in the furnace, at a point where the 
cold products have been able to reach the temperature of the hot products 
with which the furnace was charged. 
However, this solution has a major drawback which limits its application. 
This is because side charging requires the use of an actual insertion 
device which is not easy to manipulate and which therefore is generally 
used only for charging with small-sized products (billets and possibly 
small blooms). 
Moreover, a second solution is known which consists in using a reheat 
furnace. In this case, a reheat furnace is charged with hot products. With 
regard to cold products, they are introduced into a preheat furnace which 
heats them to the temperature of the hot products, before being 
transferred and then loaded with the hot products. 
Again, this solution has a major drawback. This is because in this 
application the cold products arrive at the preheat furnace via roller 
tables. A loading device takes them and deposits them in the furnace. The 
cold products are then preheated to the temperature of the hot products 
and then unloaded by means of an unloading device and deposited on roller 
tables. 
The hot products and the preheated cold products are then transported to 
the reheat furnace and are then seized by means of another loading device 
and taken into the reheat furnace in which they are heated to the 
hot-rolling temperature. 
The use of a preheat plant necessarily requires the use of a certain number 
of loading and unloading devices and of transfer devices (roller tables), 
which result not only in an offset arrangement of the two furnaces--the 
preheat furnace and the reheat furnace--and hence a significant amount of 
the floor space being taken up, but also greater cooling of the products 
between the two furnaces, which phenomenon runs counter to reducing energy 
consumption. 
BRIEF DESCRIPTION OF THE INVENTION 
The object of the present invention is therefore to help to overcome the 
drawbacks of the solutions known from the prior art by providing a device 
which improves and simplifies the transfer of metallurgical products 
between the preheat furnace and the reheat furnace, which can consequently 
be placed face to face (or aligned). 
For this purpose, the transfer device positioned between a first furnace 
and a second furnace for the metallurgical treatment of iron and steel 
products initially placed on stationary longitudinal members, which forms 
the subject of the invention, includes a frame provided with an assembly 
consisting of the juxtaposition of a plurality of movable longitudinal 
members and optionally of a plurality of rollers. The movable longitudinal 
members engaging both with a lifting/depositing frame and with a 
forward/rear translation frame, the said frames allowing the movable 
longitudinal members to describe a movement of rectangular pitch so as to 
transfer the iron and steel products between the first and second furnace, 
or so as to load the iron and steel products into the second furnace. 
For this purpose, the plant for the metallurgical treatment of iron and 
steel products includes a first, preheat furnace, one of the ends of which 
faces a transfer device, which ensures continuity with a second, reheat 
furnace, the iron and steel products being fed into the first, preheat 
furnace and/or into the second, reheat furnace. 
Other characteristics and advantages of the present invention will emerge 
from the description given below with reference to the appended drawings 
which illustrate an embodiment thereof which is devoid of any limiting 
character. In the figures:

DETAILED DESCRIPTION OF THE INVENTION 
In FIG. 1, the cold products are denoted by the reference number 1 while 
the hot products are denoted by the reference number 2. The cold products 
are loaded at the entrance of the furnace 4 while the hot products are 
introduced via a side opening 3 made in the furnace 4. 
In FIG. 2, the cold products are represented by the reference number 1 and 
the hot products by the reference number 2. The cold products 1, after 
having travelled by means of a transfer device 7, are introduced into a 
preheat furnace 5 by means of a loading device 6. After having passed 
through the preheat furnace 5, the cold products, which are heated up, are 
discharged by means of an unloading device 8 and are then positioned on 
another transfer line 9 which conveys them, at the same time as the hot 
products 2, to the reheat furnace 10 which has to bring the temperature of 
these products to the hot-rolling temperature. The hot products 2 and the 
cold products 1 are loaded, by means of a device 11, into the furnace 10 
and extracted therefrom by means of a device 12. The latter places the 
products, which have reached the desired rolling temperature, on a 
transfer line 13 which conveys them to the rolling mill 14. 
In FIG. 3, the cold products have been represented by the reference number 
1, the hot products by the reference number 2 and the rolling mill by the 
reference number 14. 
The cold products 1 travel, by means of a transfer line 15 (roller table), 
to the preheat furnace 16. These products 1 are introduced, by means of a 
loading device 17, into the furnace 16. As they travel through the furnace 
16, the cold products reach the temperature of the hot products 2. 
A transfer device 18, which forms the subject of the invention, is 
positioned between the preheat furnace 16 and the reheat furnace 19. This 
transfer device 18 handles the cold products 1 preheated to the 
temperature of the hot products 2 (the latter arriving at the device 18 by 
means of a transfer device 20). 
When the products 1 and 2 are introduced into the reheat furnace 19 and, 
after having travelled through 19 in order to reach the suitable 
temperature for the purpose of rolling, they are extracted by means of an 
unloading device 21 which deposits them on a transfer line 22 going 
towards the hot-rolling mill 14. 
According to a preferred embodiment of the transfer device 18 forming the 
subject of the invention, this device comprises (the reader is referred to 
FIG. 4) a frame placed between the preheat furnace 16 and the reheat 
furnace 19. This frame is provided with an assembly consisting of a 
juxtaposition of a plurality of movable longitudinal members 24 and of a 
plurality of rollers 30, the latter being positioned in the same plane and 
so as to be continuous with the transfer means 20. Stationary longitudinal 
members 23 also lie in the same plane as the hearth of the preheat furnace 
16 and the hearth of the reheat furnace 19, as well as in a plane parallel 
to the transfer means 20 (roller table) which conveys the hot products 2. 
According to another embodiment, the rollers 30 are not incorporated in the 
frame of the transfer device 18 but are attached, substantially in the 
same plane as the stationary longitudinal members 23, to a subsidiary 
frame which engages for example, with the preheat furnace 16 and with the 
reheat furnace 19. 
The movable longitudinal members 24 move with a rectangular pitch 
consisting of four main movements: 
a lifting movement, 
a forward translation movement, 
a depositing movement, and 
a rear translation movement. 
The movable longitudinal members 24 engage both with a lifting and 
depositing frame 25 and with a forward/rear translation frame 26. The 
lifting/depositing movements of the frame 25 and the forward/rear 
translation movements of the frame 26 are provided by mechanical, 
hydraulic or other lifting means 27 and translation means 28, 
respectively. 
Firstly, products 1 leaving the preheat furnace 16 are positioned so as to 
bear on the stationary longitudinal members 23. The lifting frame 25 is 
then in the low position and the translation frame 26 in the rear 
position. In this configuration, the movable longitudinal members 24 are 
then below the products 1 to be transferred to the reheat furnace 19. 
Secondly, the lifting means 27 (by means of the combined action of 
cylinders and of inclined faces 29) raise the frame 25 and therefore the 
movable longitudinal members 24, thereby lifting the products 1. 
Thirdly, the means 28 move the translation frame 26 translationally 
forwards so as to transfer the products 1 which are on the movable 
longitudinal members 24 into the reheat furnace 19. 
Fourthly, the lifting means 27 position the movable longitudinal members 24 
so as to be level with the stationary longitudinal members 23 lying in the 
same plane as the hearth of the furnace 19 so as to deposit the products 1 
in the reheat furnace 19. 
The final operation consists in bringing the translation frame 26 and the 
movable longitudinal members 24 which engage therewith into the rear 
position, using the translation means 28, which constitutes the initial 
position of the cycle. 
Of course, the movement of the movable longitudinal members 24, by means of 
the frames 25 and 26, with respect to the products 1 is identical to the 
operation of these same longitudinal members 24 in the case of 
transferring products 2 from the transfer line 20 into the furnace 19. In 
this case, the stationary rollers 30 act as the stationary longitudinal 
members 23, the stationary rollers 30 being positioned on the end of and 
substantially in the same plane as the transfer line 20. 
The invention as described above offers many advantages. It allows the 
aligned arrangement of the preheat and reheat furnaces, thereby saving a 
considerable amount of floor space. It also allows hot products to be 
loaded into the preheat furnace so as to constitute a temporary hot 
storage area when the rolling mill is stopped and when the continuous 
casting line is in operation. 
Of course, it remains to be stated that the present invention is not 
limited to the embodiments described and illustrated above but encompasses 
any variant thereof.