JP4092286B2 - Rod delivery system and method - Google Patents

Abstract

A method and system are disclosed for receiving a hot rolled bar product from a rolling mill, and for delivering the bar product to a cooling bed. A shear subdivides the bar product into bar segments and alternately directs the bar segments to one or the other of two downstream intermediate paths for continued travel thereon. A switch on each of said intermediate paths alternately directs bar segments traveling thereon to one or the other of two respective downstream delivery paths for continued travel thereon to the cooling bed. Decelerators slow the bar segments traveling along the delivery paths. <IMAGE>

Description

  The present invention relates generally to continuous hot rolled rod mills, and more particularly to a system and method for delivering hot rolled products of such mills to a cooling bed.

  In modern rod mills currently in operation, the hot rolled rod product leaving the final mill stand is cooled by passing through one or more water boxes. These rod products are then subdivided into rod segments by a split shear, which is equipped with a switching mechanism that is connected to one or the other of the two delivery paths that follow the cooling bed downstream. Oriented alternately. The rod segment moving along the delivery path is decelerated by the action of a pinch roll unit, friction pad, or the like so that the rod segment is moved laterally onto the cooling bed. , Slide progressively and stop.

  When mills roll larger product sizes, for example, when rolling products with diameters greater than about 10.0-12.0 mm, this type of configuration is used to achieve a relatively high tonnage rate. Can be achieved. Larger products of this type have sufficient column strength to resist buckling when pushed through the water box and at relatively high mill delivery speeds of approximately 10-30 m / sec.

  However, as the product size decreases, their column strength also decreases, so the mill delivery speed must be reduced to avoid buckling when pushing smaller product sizes through the water box. Disappear.

  That is, for example, a single strand mill for rolling a 8.0 mm rod and delivering it to the laying head can be operated at a delivery speed of 60 m / second or higher, and 85 tons / hour. Bring capacity. However, similar mills for rolling 8.0 mm rods and passing them to the cooling bed must always roll at a very low delivery speed of about 32 m / s, resulting in capacity. Decreases by about 45 tons / hour. Many reasons for lowering rod product delivery speed are due to the fact that conventional rod handling systems cannot move faster until the product is stopped and moved laterally onto the cooling bed.

  The present invention aims to increase the tonnage rate in a mill capable of rolling rod products, in particular rod products of smaller product size, for example having a diameter of less than about 12.0 mm.

  The present invention also increases the rate at which smaller rod products are delivered from the mill and then decelerates such rod products before being cooled in the water box prior to delivery to the cooling bed. This is another purpose.

  In accordance with the present invention, hot rolled rod products are subdivided into rod segments by a split shear and the rod segments are alternately directed to one or the other of two downstream intermediate paths. . Thereafter, the switching on each intermediate path alternately directs the rod segments to one or the other of the two downstream delivery paths that follow the cooling bed. These rod segments move along four delivery paths and are preferably subjected to at least two stages of deceleration. The first stage deceleration has the effect of decelerating the rod segment to an intermediate speed that is lower than the speed at which the rod product is delivered from the mill, and the second stage deceleration is suitable for delivery to the cooling bed, The effect is to further decelerate the rod segment to a lower speed. The rod segment is cooled between a first stage and a second deceleration stage moving at an intermediate speed.

Referring first to FIGS. 1 and 2A, 2B, and 2C, a system according to the present invention between a final rolling stand 10 of a continuous hot rolling rod mill and a conventional carryover cooling bed 12 is shown. ing. Rod product exiting from roll stand 10 along path P _A is passed through a series of water boxes 14, then, it is subdivided into rod segment by dividing shear 16. The shearing machine 16, which can be of a conventional design well known to those skilled in the art, provides a switching mechanism that alternately directs the subdivided rod segment to one or the other of the two intermediate paths P _B , P _C downstream thereof. I have. Subsequently, a switch 18 on the intermediate path P _B directs those rod segments alternately to one or the other of the two delivery paths P _D , P _E downstream thereof, and a switch 20 on the intermediate path P _C. Similarly, the product segments are alternately directed to one or the other of the two delivery paths P _F and P _G downstream thereof. A side-by-side set of delivery paths P _D , P _E and P _F , P _G passes through a series of water boxes 22 to pinch roll units 24, 26, after which two opposing 180 ° curves C ₁ , around the side loop partially defined by C ₂ . Curve C ₁ is formed in part by a removable guide section 28. This side loop has a water box 30 and the two sets of delivery paths P _D , P _E and P _F , P _G are in curve C ₂ before continuing to pinch roll units 32, 34. Aligned vertically and then reaches the cooling bed 12.

Referring to FIG. 3, using single stage guide units 36, 38 with laterally spaced guide pipes 40, laterally arranged and vertically offset delivery paths P _D , P _E and Aiming the rod segment along the set of P _F and P _G , and using the two-stage trough unit 42, the rod segment is oriented when the two sets of delivery paths are aligned vertically It will be understood.

Although FIGS. 4 and 5 best seen with reference to the pinch roll unit 32 has two sets of pinch rolls 44 and 46, each being aligned with delivery paths P _G and P _F, pinch roll unit 34 also has a pinch roll 48, 50 of the two sets, each of which is aligned with the delivery path P _D and P _E. Each set of pinch rolls is driven independently via a drive shaft 52, a gear box 54, and a motor 56. These pinch rolls are driven at a speed selected to provide proper deceleration of the rod segments that are frictionally gripped between them.

  The pinch roll units 24, 26 are similar in construction, but are arranged slightly differently for placement with laterally arranged and vertically offset guide paths.

Next, for an example of the operation of the system described above, to a rod product cooling bed having a diameter of 8.0 mm exiting the final rolling stand 10 with a relatively high speed of 60 m / sec and a temperature of about 950-1050 ° C. This will be further described in relation to the delivery of. The water box 14 has been shut down and the rod product is free to travel through it to the shear 16 where it is subdivided into continuous rod segments. A shear switching mechanism directs these rod segments alternately to the intermediate paths P _B , P _C. The rod segments moving in the path P _B are then directed alternately by the switch 18 to the delivery paths P _D , P _E , and the rod segments moving in the intermediate path P _C are also alternately switched by the switch 20. Directed to delivery paths P _F and P _G.

Thereafter, pinch roll units 24 and 26 act to first decelerate the rod segment to a lower intermediate speed of about 30 m / sec. This rod segment is directed by the curved guide section 28, turns around the side loop and passes through the water box 30. The linear distance between the pinch roll units 24, 26 and the water box 30 is preferably shorter than the length of the rod segment. That is, the rod segments enter the water box 30 at a suitably decelerated speed while the pinch roll units 24, 26 are acting on them. Water box 30, the rod segment before exiting the curve C _2, acts to reduce their temperature to about 500 to 600 ° C.. Thereafter, the pinch roll units 32, 34 act and the rod segment is further decelerated to about 3-8 m / sec so that the rod segment slides to the inlet end of the cooling bed 12 and stops. it can. From there, a movement mechanism (not shown) acts to shift the rod segments laterally across the cooling bed where they are further cooled before they reach the delivery end of the bed.

Of particular importance to the present invention is that multiple delivery paths are provided for continuous rod segment exit from the shear 16 where multiple delivery paths for the product through the switches 18, 20 are coupled. It is. In the case of the previous example, successive rod segments repeat and follow the following order:
Intermediate path delivery path
P _B P _D
P _C P _F
P _B P _E
P _C P _G

  Each delivery path is directed to only one out of four rod segments, so it will decelerate one rod segment along each delivery path until the next rod segment arrives. Sufficient time and intervals are given.

As shown in FIG. 6, when dealing with larger diameter, slower rod products, the system can be reconfigured by replacing the curved guide section 58 with a straight tapered guide section 58. Is called. This bypasses the side loop constructed between the 180 ° curves C ₁ and C ₂ .

  In this mode of operation, the increased column strength of the larger diameter product and the slower mill delivery speed allow cooling to be performed within the water box 22. In that case, two-stage deceleration is first performed by the pinch roll units 24 and 26, and then by the pinch roll units 32 and 34.

  Thus, it will be appreciated that the system of the present invention is a very flexible system since it can handle a wide range of products at suitably high tonnage rates. For smaller diameter products, such as products having a diameter in the range of 6.35 to 12.0 mm, the water box 22 is freely passed through and is subjected to initial deceleration by pinch roll units 24 and 26 before the water. -By performing the cooling in the box 30, it is possible to handle at a relatively high mill delivery speed of 60 to 32 m / sec. For products having a larger diameter of greater than 12.0 mm and exiting the mill at a slower speed of less than about 30 m / s, in the water box 22 prior to initial deceleration by the pinch roll units 24, 26 Cooling can be performed.

  As shown in FIG. 7, it is also possible to use two systems of the type shown in FIG. 1 and arrange them side by side and supply them to the same cooling bed.

1 is a plan view of a system according to the present invention in a configuration suitable for handling rod products of smaller diameter and higher speed. FIG. FIG. 2 is an enlarged view of a region between reference planes A and B in FIG. 1. It is an enlarged view of the area | region between reference plane BC of FIG. FIG. 2 is an enlarged view of a region between reference planes CD in FIG. 1. It is the expanded sectional view seen along the 3-3 line of Drawing 2B. FIG. 4 is an enlarged front view of a pair of pinch roll units as viewed along line 4-4 of FIG. 2B. FIG. 5 is a partial plan and horizontal sectional view taken along line 5-5 in FIG. FIG. 3 is a plan view similar to FIG. 2B showing a system reconfigured to handle a rod product having a larger diameter and a slower moving speed. FIG. 2 is a plan view showing that the two systems of FIG. 1 are arranged in a mirror image.

Explanation of symbols

10 final rolling stand, 12 cooling bed, 14,30 water box, 16 split shear, 18 switching, 20 switching, 22 water box, 24, 26, 32, 34 pinch roll unit, 28 guide section, 36,38 Single stage guide unit, 40 Guide pipe, 42 Two stage trough unit, 44,46,48,50 Pinch roll, 52 Drive shaft, 54 Gear box, 56 Motor, C ₁ curve, C ₂ curves.

Claims (10)

A system for receiving a hot rolled rod product from a rolling mill and delivering the rod product to a cooling bed,
Shearing means for alternately directing the rod segment to one or the other of them for subdividing the rod product into rod segments and for continuous movement in two downstream intermediate paths When,
For alternately directing the rod segments moving in each said intermediate path to one or the other of them for continuous movement to said cooling bed in two downstream delivery paths in each downstream Switching means on each of the intermediate paths;
Deceleration means for decelerating the rod segment moving along the delivery path;
With
The deceleration means is
First and second reduction means spaced apart from each other along the delivery path, the first reduction means acting to decelerate the rod segment to an intermediate speed that is slower than the speed at which the rod product is delivered from the rolling mill. A deceleration means of
Second deceleration means operative to further decelerate the rod segment from the intermediate speed to a slower speed suitable for delivery to the cooling bed;
Including
A system wherein the distance between the first and second deceleration means is greater than the length of the rod segment. The system of claim 1, wherein
The system further comprising cooling means for cooling the rod segment moving along the delivery path. The system of claim 2, wherein
The cooling means is
First and second cooling means spaced apart from each other along the delivery path, the first cooling means disposed upstream of the first speed reduction means;
Second cooling means disposed between the first and second deceleration means;
A system comprising: The system of claim 3, wherein
The system characterized in that the distance between the first deceleration means and the second cooling means is less than the length of the rod segment. The system of claim 1, wherein
The system according to claim 1, wherein the speed reducing means comprises a pinch roll unit. The system of claim 2, wherein
The cooling means comprises a water box for applying water to the rod segment. A method of receiving a hot-rolled rod product from a rolling mill and delivering the rod product to a cooling bed,
Subdividing the rod product into rod segments and directing the rod segments alternately to one or the other of them for continuous movement in two intermediate paths;
Alternately directing rod segments moving along the intermediate path to one or the other of them for continuous movement to the cooling bed in each of the two delivery paths;
Decelerating the rod segment moving along the delivery path in two stages;
With
The step of decelerating in the two stages comprises a first stage of decelerating the rod segment to an intermediate speed that is slower than the speed at which the rod product is delivered from the rolling mill, and the cooling bed being slower from the intermediate speed. A second stage of deceleration that further decelerates the rod segment to a speed suitable for delivery to
The method of claim 2, wherein the second stage deceleration is performed after the first stage deceleration is completed. The method of claim 7 , wherein
The method further comprises the step of cooling the rod segment moving along the delivery path. The method of claim 8 , wherein
The method further comprises the step of cooling the rod segment moving along the delivery path. The method of claim 9 , wherein
The method wherein the cooling occurs while the rod segment is undergoing deceleration in the first stage.

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