Braking device for axially receiving and transversely discharging rolled bars

The braking channel comprises a fixed channel section for each strand of bars, provided with two open-bottom chambers which are normally covered up by the sliding surfaces of a pendulum structure, the effect of which will brake the bars and let them come to rest. For bar discharge on to the cooling bed, the pendulum structure is swivelled rhythmically toward the right and left to positions in which the discharge openings reach underneath a pair of chambers. The kinematic inversion could also be applied, in which case the sliding section would be in a fixed position and the channel sections would move in pendulum fashion.

The invention relates to a braking channel for rolled bars, especially for 
rounds, which discharge from a mill train at a high speed rate, consisting 
of a channel section designed to form at least two adjacent feed channels 
for lateral guidance of the bars, and of a sliding section forming sliding 
surfaces for the bars, the channel section or the sliding section being 
movable relative to the other fixed section in a transverse direction to 
the bars, such that transverse movement will let the bars present in the 
feed channels alternately come clear to drop down freely from the 
channels. 
A braking channel of this type has become known by DE-A1-20 08 250 in which 
the channel section formed by the feed channels is in a fixed position and 
the sliding section is designed to form a pendulum structure which is 
driven to swivel reversingly about an overhead line shaft positioned in 
the running direction of the bars. The alternating swivel motion of the 
sliding surfaces in the pendulum structure, which support the bars present 
in the two feed channels, brings about alternate bar discharge, whereby, 
according to the prior art, the bars are braked step by step in multiple 
channels. However, the disadvantage of this braking channel construction 
is that the feed channels are open at their tops so that particularly 
small rounds may easily escape from the channels. This affects the 
functional reliability of the braking system. 
Enclosed feed channels of a braking channel for rolled bars have become 
known by DE-A-465 625. The feed channels of this braking channel are 
provided with through longitudinal slots. By the reversing movements of 
the feed channels, these slots may be selectively covered up by fixed 
cover means. Since the tubular feed channels are controlled to rotate 
reversingly about their longitudinal axes, retraction of a slot from the 
area of the cover means will open up its respective channel and permit the 
bar which has come to rest in the channel to drop out freely. This known 
braking channel requires the use of a separately controlled rotary drive 
for each feed channel, contrary to the solution under DE-A1-20 08 250 
which utilizes a single drive for transverse movement of the pendulum type 
sliding section. 
Proceeding from the braking channel in DE-A1-20 08 250, the invention is 
based on the problem of braking the bars in enclosed feed channels, yet 
maintaining the advantage of using a single drive to bring about relative 
movement between the channel section forming the feed channels and the 
sliding section forming the sliding surfaces for discharge of the bars 
that have come to rest. 
According to the invention, this problem may be solved by the use of two 
chambers open at their bottoms, which form the feed channels of the 
channel section and which are covered up by the sliding surfaces of the 
sliding section when the two relatively movable sections are in the center 
position. When the sliding surface, due to its definite length, is 
alternately positioned outside the vertical projection of one of the 
chambers by the relative transverse movement between the channel section 
and the sliding section, then the bar present in that chamber will be free 
to drop downward, advantageously into the groove of an oscillating rake 
type cooling bed. It will not be possible for the bars to escape during 
the braking procedure, since the chambers will be fully enclosed in the 
center position of the two relatively movable sections. Since the 
inventive braking channel is required to be relatively long, it should 
appropriately consist of a multiple of channel and sliding sections 
provided with entry funnels, arranged one behind the other similar to rod 
guiding pipe units, and with a common drive. 
The invention described so far is independent of whether the channel 
section forming the chambers or feed channels is in a fixed position and 
the sliding section is transversely movable, or vice versa. However, in 
the preferred solution, the channel section forming the feed channels is 
fixed and the sliding section is transversely movable, the chambers of the 
channel section being separated by a web. In the center position of the 
sliding section, this web will cover up a discharge opening provided 
within the sliding surface of the sliding section and disposed to service 
both chambers. By transverse movement of the sliding section, the 
discharge opening may be alternately moved into position underneath one 
chamber or the other. The advantage of this solution is that the feed 
channels or chambers will always be in alignment with the bars as they 
enter the braking channel. The alternative solution in which the sliding 
section is in a fixed position and the channel section forming the feed 
channels is transversely movable and in which transverse movement of the 
channel section will move the chambers alternately to a position outside 
the sliding section, requires the use of swivel pipes for each chamber to 
aid the sequence of bars to be braked, these pipes being located at the 
entry end of the braking channel to form extensions to fixed guide pipes 
and being connected such that they are forced to follow the movements of 
the channel section or chambers.

As shown in FIG. 1, the inventive braking channel consists of a multiple of 
individual units A, B, C, etc. arranged in close succession. The first 
braking channel unit A which is shown only in part, same as unit C, is 
located at the entry end of the rake type cooling bed R partially shown in 
FIG. 2. The fixed portion of the cooling bed R has walls W sloping upward 
for attachment of the braking channel units. The common drive for all 
braking channel units includes a swivel shaft 3 extending over the entire 
length of the channel. At least one drive lever 4 is rotatingly connected 
to the shaft 3 and is actuated by the piston rod 5 of a pressurized 
cylinder 6. 
The actual braking channel comprises a multiple of swivel levers 7 which 
are keyed to the swivel shaft 3 and the lower ends of which hold a channel 
section 8 with two open-bottom chambers 8a and 8b. In the center position 
of the swivel levers 7 or channel sections 8 shown in the drawing, both 
chambers 8a and 8b are covered up by a fixed sliding section unit 9. The 
sliding surface of the sliding section 9 is curved to form an arc 
corresponding to the circular motion of the channel section 8, i.e. the 
center of curvature on the sliding surface is the centerline of the swivel 
shaft 3. A slight amount of clearance is provided between the webs 
enclosing the two chambers 8a, 8b of the channel section 8 and the sliding 
surface of sliding section 9. 
As more clearly shown in FIG. 1, the fixed sliding section 9 is held in 
place by hanger bars 10 located outside of each swivel lever 7. The upper 
ends of these bars are attached to cross-stays W' on the cooling bed walls 
W and reach through transverse slots S in the movable channel section 8 
(FIG. 3). The purpose of these transverse slots S will be more closely 
explained in connection with FIG. 3. 
The braking channel shown in FIGS. 1 and 2 is designed for single-strand 
operation in the rolling mill, i.e. the rolled bars 1 and 1a sheared on a 
rotary shear are alternately fed to the chambers 8a and 8b of the channel 
section 8 one after the other. The feed pipes for bars 1 and 1a ahead of 
the first channel unit A and their particular features will be described 
later on in connection with FIG. 6. It is assumed that bar 1 comes to rest 
by the braking effect of the sliding section 9 and a web section of the 
channel section 8, at which time the subsequent bar 1a will enter chamber 
8b. For discharge of bar No. 1, a swivel motion of swivel lever 7 will 
move the channel section 8 clockwise into the position shown in FIG. 3. 
This will move chamber 8a to a point beyond the covering area of sliding 
section 9 and bar No. 1 may drop down freely against the sloping cooling 
bed walls W and into the first groove of the cooling bed R. Bar 1a in 
chamber 8b will follow this transverse movement of channel section 8 
toward the left. When the swivel lever 7 and the channel section 8 return 
to the center position shown in FIG. 1, the next bar may enter chamber 8a 
which will now be covered up. The discharge position of channel section 8 
for bar No. 1a is shown dash-dotted in FIG. 3. In both bar discharge 
positions, the transverse slots S will be in a limit position--as shown in 
FIG. 3 for one discharge position--in which the channel section 8 will, at 
most, come into contact with the hanger bars 10, so that the chambers and 
the bars present in these chambers will pass the hanger bars 10 at a safe 
distance. Thus, the minimum length of the transverse slots S is at least 
equal to the overall transverse shifting path of the channel section 8. 
The exemplary embodiment in FIG. 4 to 6 is adaptable to the SLIT process 
used in rolling mills, i.e. bars are rolled 1 with 1a and 2 with 2a 
coherently and are separated by a longitudinal slitting cut. The example 
in FIG. 4 differs from FIG. 2 in that the channel section 18 is provided 
with four open-bottom chambers and with two fixed sliding sections 19 
arranged in reverse image. These sections are separated one from the other 
by a free bar discharge area and, in the center position of the channel 
section 18 shown in FIG. 4, each will cover up a neighboring pair of 
chambers. In this case, of course, each sliding section 19 is provided 
with its own hanger bar 10. The swivel lever 17 is enlarged in width to 
suit the channel section 18. 
The bar discharge area located between the sliding sections 19 is 
subdivided into two halves by vertically arranged fixed separating bars 20 
to permit bars discharging into this area to feed into two neighboring 
grooves on the rake type cooling bed R. 
The function of the inventive braking channel adaptable for use in the SLIT 
process may best be understood from FIG. 5a to 5c. FIG. 5a shows the 
center position of the channel section 18 in relation to the two sliding 
sections 19 which are spaced to provide the common bar discharge area 21. 
The separated bars 1 and 1a produced from an initial coherently rolled 
double bar are fed to those particular chambers of the channel section 18 
which are opened up simultaneously when the channel section 18 swivels to 
one side, as shown in FIG. 5b. These bars 1 and 1a which enter the channel 
section simultaneously will come to rest simultaneously and will also drop 
out simultaneously. When channel section 18 is in the discharge position 
shown in FIG. 5b or in the center position shown in FIG. 5a, the separated 
bars 2 and 2a of the next double bar are fed into the second two chambers. 
These bars are discharged in the opposite discharge position (FIG. 5c) and 
the next pair of bars 1 and 1 a may now enter the channel section. 
The situation ahead of the braking channel in FIG. 4 is shown in FIG. 6. 
The feed channels or chambers 18a to 18d of an initial braking channel 
unit A (FIG. 1) are shown schematically at the right in FIG. 6, the 
chambers being funnel-shaped at their entry ends. Each chamber is preceded 
by a swivel pipe 23, 24, 25, 26. These pipes are pivotally supported at 
their entry ends. Their exit ends are connected to the channel section 18 
by hinged bolts 28 in such a manner that each swivel pipe is forced to 
follow the movements of the channel section and, thus, of their associated 
chambers 18a to 18d. Also in FIG. 6, fixed guide pipes 29, 30, 31, 32 are 
provided at the entry end ahead of the swivel pipes 23 to 26 with bars 1, 
1a of a coherently rolled double bar entering pipes 29 and 31, i.e. the 
pipes associated with chambers 18a and 18c. The next pair of bars of a 
strand are fed into guide pipes 30, 32. Swivel pipes 23 to 26 have all 
been swivelled from their straight center positions to a position which 
would come near to the situation shown in FIG. 5c in which chambers 18b 
and 18d are in their discharge positions for discharge of a previous pair 
of bars, whilst chambers 18a and 18c for the next bars 1, 1a are still 
covered up. 
It goes without saying that the braking channel exemplified in FIG. 2 and 3 
merely utilizes two swivel pipes 23, 24 and two guide pipes 29, 30. 
An example of the preferred solution is shown in FIG. 7. A sliding section 
37, designed to form a pendulum structure and shown in its center 
position, may be swivelled periodically toward the right and left about a 
swivel shaft 33. This exemplary embodiment is also designed for two-strand 
operation and is therefore provided with two feed channel sections 38, 
each comprising two open-bottom chambers 38a and 38b attached to fixed 
brackets 39 along their lengths. In the center position of the sliding 
section 37 shown, these chambers are covered up by the circularly curved 
sliding surface 37a, i.e. the two discharge openings 40 in the sliding 
section are covered up by the webs 38c of the channel sections 38. The 
function of a braking channel according to FIG. 7 essentially corresponds 
to that of the previous examples, except that in this case the discharge 
openings 40 in the sliding section 37 will alternately open up chambers 
38a and 38b for discharge of the bars which have come to rest inside the 
chambers. The discharge openings 40 can be spaced sufficiently close, in 
order that simultaneously discharging bars may drop into the first two 
grooves R1 and R2 of the cooling bed, separately and without deflection.