JPS6315966B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a heating furnace operation method that minimizes equipment costs and running costs in a heating furnace located between a continuous casting process and a rolling process, and absorbs the difference in throughput between the two processes. It is something.

There is a big difference in processing speed between continuous casting equipment and rolling equipment. Therefore, the heating furnace placed between the two processes is required to act as a buffer zone to absorb the difference in processing capacity as much as possible.

That is, it is desirable to be able to continuously charge the heat-receiving material sent from the continuous casting equipment into the furnace without dissipating the heat it possesses while extracting the heat-receiving material to the rolling line. From a thermoeconomic perspective, it is desirable to have a high hearth occupancy rate of the heated material, a minimum furnace length that provides the required amount of heat, and a low equipment cost. For this reason, it has recently been proposed to make the heating furnace a split hearth type. Although this split hearth furnace has advantages, it also has problems.

In other words, the split hearth type heating furnace functions well when the same number of heated materials are operated at a constant charging and extraction pitch, but this condition does not always continue. In addition, the number of heated materials, charging pitch, and extraction pitch often vary depending on equipment specifications, steel type, and production volume.

In the conventional prior art, for example, there is a method of absorbing the unmatching operation between continuous casting and rolling by using a three-part furnace type heating furnace as shown in Fig. 1. , (ro), (ha)
and (in) explain.

(a) When the heat-receiving materials 9 are charged one after another, they are connected by a continuous mechanism, and the divided walking beams A, B, and C are synchronously driven [FIG. 1(a)].

(b) When the heated material group 9 is transferred from walking beam A and moved to walking beams B and C, A is disconnected from B and C, and A can be driven independently from B and C. It becomes [Figure 1 (ro)].

(c) Walking beam A moves the newly charged material to be heated 9, and beams B and C sequentially extract the group of previously charged materials to be heated ₉₁ [FIG. 1 (a)].

(d) As shown in FIG. 1 (d), when the walking beams are removed from the heated material 9 ₁ , the walking beams B and C are separated, C is driven independently, and A and B are synchronized and transferred into the furnace. However, the above-mentioned movement is only possible when the walking beam B is empty, and depending on the throughput and charging time pitch of the groups of materials to be heated 9 and ₉₁ , the effect of the split hearth may vary. cannot perform. That is, in the state shown in FIG.
must wait on walking beam A until walking beam B is empty.
Moreover, if there is a waiting time for one cast, the pitch of the CC (continuous casting machine) is a fixed time, making it even more difficult to use a split hearth.

Furthermore, when a split hearth is driven independently, an empty space in which no heated material is placed within the range of the walking beam stroke, that is, an ineffective furnace length, is required, which increases the total furnace length, increases equipment costs, and reduces furnace body radiation. The fuel consumption rate will increase due to increased heat dissipation.

Furthermore, although the material to be heated is continuously charged, if the charging and extraction pitches are different, the materials to be heated cannot be arranged at equal intervals in the furnace, resulting in a so-called "missing" situation. Such a situation cannot be corrected to equal pitch even in the split hearth type, and there is a problem that the hearth occupancy rate of the heated material decreases and the fuel consumption rate increases.

The present invention provides a heating furnace disposed between a continuous casting process and a rolling process, and is equipped with a matching charger in front of the heating furnace to adjust the stroke of entering the furnace, thereby reducing the difference in throughput between the two processes. In addition to absorbing water, there are no regulatory conditions such as hearth splitting that cause it to become empty.
It is compatible with a wide range of unmatching operations, B. Minimizes equipment costs by eliminating the need for an ineffective furnace length at the split position, and C. It eliminates gaps in the furnace and increases the hearth occupancy rate of heated materials. It has characteristics.

An embodiment of the present invention will be described below.

FIGS. 2(a), 2(b), and 3 show the present invention, in which the heating furnace 1 is arranged as a buffer zone between the continuous casting process and the rolling process to absorb the difference in capacity between them. Reference numeral 2 in FIG. 3 denotes a matching charger, and the matching charger 2 is composed of a rack 3, a pinion ₃₁ , a ram ₄₁ , a hydraulic cylinder 5, a drive lever 6, and a guide roller. The charging roller table 8 allows
The material 9 that has been sent to the front side of the heating furnace 1 is unloaded within the heating furnace 1 and placed on a fixed skid 10, and the material 9 is sequentially advanced through the furnace by an in-furnace movable skid 11.

In the heating furnace of the present invention, the charger 2 is operated with a stroke SMC calculated by the formula SMC=Ss+Swb(N-n)+ΔSwb each time the material to be heated 9 is charged, and the charger 2 charges the material to be heated 9 into the heating furnace 1. This is a heating furnace which is equipped in front of the heating furnace, and its basic heating will be explained with reference to FIGS.

A The heated material A is extracted from the inside of the furnace onto the extraction table 12.

B Δt ₁ hour (difference between extraction pitch and charging pitch)
Later, the material to be heated is sent to the front of the furnace.

C Grasp the position of the last material C charged in the furnace and adjust the stroke SMC of charger 2.
is calculated by the formula Ss+Swb(N-n)+ΔSwb.

D Operate charger 2 with the calculated stroke amount and charge material RO into position RO ₁ in the furnace.

E Material # ₁ is transported into the furnace along with other materials to be heated to the extraction pitch.

The details of the heating furnace in the present invention will be explained in detail with reference to FIG.

In FIG. 4, the heated material 9 is indicated by I to I, the charging port is indicated by 12, and the extraction port is indicated by 13.

After ₂ hours, the heated material is extracted from the extraction port 13,
The materials to be heated in the furnace are transferred from the stroke loading side of the walking beam to the extraction side. Now the heated material A has moved to the position B, and the position A is now open. t After ₁ hour, the material to be heated is sent to the front of the furnace.
It is loaded into the open position A.

Next, after 2×t ₂ hours, the heated material is extracted, and Q moves to position B. Furthermore, after 3×t ₂ hours, E is extracted, Q moves to C, and at this point, A and B are in the same position. The material to be heated that is sent in this state is charged into position B by increasing the stroke of the charger so as not to cause any gaps in the furnace. 5×t After ₂ hours, Ha will be extracted and Li will be in the position of D. At this time, the nuts sent to the front of the furnace are charged to position C by a charger.

That is, the present invention calculates the charge stroke amount from the distribution of the heated material in the furnace for each heated material to be charged, and eliminates the missing state of the heated material in the furnace.
This stroke amount is expressed by the following formula.

SMC=Ss+(N-n)Swb+ΔSwb Here, S: Charging stroke of the nth charge Ss: Standard stroke Swb: Walking beam stroke ΔSwb: Walking beam stroke error N: The nth charge already in the furnace For example, in Figure 4, the stroke amount for n = 3rd stroke is 5, and the number N extracted is 5, and Si = 3 = Ss + (5-3) Swb + ΔSwb = Ss + 2Swb + ΔSwb. .

A specific example of the operation of the matching charger of the heating furnace of the present invention will be explained. For example, Figure 5 shows the movement of the matching charger for heated materials when the charging pitch on the charging port side is 2.26 minutes, the extraction pitch on the extraction port side is 1.57 minutes, and the number of rolled pieces at one time is 31. It shows.

Thirty-one heated materials are charged into the furnace.

After 1.57 minutes, 31 materials to be heated are extracted, and at the same time, all the materials to be heated in the furnace are moved to the extraction port 13 side.

After 2.26 minutes, the material to be heated arrives in front of the furnace and is charged into the furnace at a position 101 by a matching charger. At this time, the charger stroke is
It is ST101.

The same movement is repeated, and the materials to be heated that arrive at the front of the furnace are sequentially charged into the furnace at equal intervals, regardless of the extraction pitch.

When 48.67 minutes have passed and 31 pieces have been extracted, 21.33 pieces are left in the furnace due to reasons such as changing the rolls on the rolling process side.
Although there is a waiting time of 30 minutes, during this time the material to be heated is sent to the front of the furnace at intervals of 2.26 minutes and continues to be charged into the furnace.

Under these conditions, the stroke of the charger gradually increases from the heated material 101 to the heated material 122, and from the heated material 123 onwards, it becomes smaller due to the extraction waiting time, and when extraction starts, the stroke increases again. The operation of the charger is repeated as the size increases, making it possible to absorb the difference in capacity between the continuous casting process and the rolling process.

Further, in the present invention, for example, when a trouble occurs in the continuous casting equipment or during transportation, a situation may occur in which a large number of pieces of heat-receiving material are sent to the front of the furnace and the heat-receiving materials are left on standby outside the furnace. In this case, it is desirable to charge the heated material into the furnace quickly to prevent heat radiation from the heated material. To deal with this situation, in the present invention, as shown in FIG. 6, a charging side walking beam 11 and an extraction side walking beam 1 are provided.
It is also possible to have a _two -part hearth. In this case, the walking beam frame 14,1
4 ₁ are connected by a coupler 17, and the walking beams 11 and 11 ₁ can be operated simultaneously or independently using the cylinder 15 for forward and backward movement and the cylinder 16 for vertical movement. Then, the group of materials to be heated 9 is charged into the furnace by the matching charger ₂ and the charging side walking beam 11, regardless of the extraction side walking beam 11. In normal operation, both walking beams 11, 11
₁ is a connector 17 that enables the devices to be connected in series for synchronized operation.

As described above, in the present invention, the heating furnace disposed between the continuous casting process and the rolling process is equipped with a matching charger that adjusts the furnace insertion stroke, thereby increasing the processing capacity between the two processes. The effects of the present invention are remarkable, such as absorbing the difference, increasing the hearth occupancy rate, improving thermal efficiency, and minimizing running costs for heating furnace equipment.

[Brief explanation of the drawing]

(i), (ro), (ha) and (ni) in Figure 1 are 3
An explanatory diagram of the operation of the divided hearth, (a) in Fig. 2 is a plan view of an embodiment of the present invention, (b) in Fig. 2 is a side view of an embodiment of the present invention, and Fig. 3 is a diagram of the present invention. FIG. 3 is a longitudinal sectional view of one embodiment of the invention. FIG. 4 shows an embodiment of the present invention.
FIG. 5 is an explanatory diagram showing charging and extraction states in further detail in one embodiment of the present invention. FIG. 6 is a longitudinal cross-section of another embodiment of the present invention. It is a diagram. 1: Heating furnace, 2: Matching charger,
3: Rack, ₃₁ : Pinion, ₄₁ : Ram, 5: Hydraulic cylinder, 6: Drive lever, 7: Guide roller, 8: Charging roller table, _9,91 : Heated material group, 10: Fixed skid , 11: Movable skid, 12: Extraction table, 14: Walking beam frame, 15: Cylinder for forward and backward movement, 1
6: Up/down cylinder, 17: Connector.

Claims (1)

[Claims] 1. In a continuous heating furnace disposed between a continuous casting process and a rolling process, the stroke calculated by the following formula
How to operate a continuous heating furnace in which materials to be heated are charged onto the heating furnace using a charger in SMC, SMC = Ss + Swb (N - n) + ΔSwb, where, Ss: Charger reference stroke, Swb: Walking beam stroke, N: Already in the furnace ΔSwb: Walking beam stroke error.