JPH01139986A - walking beam furnace - Google Patents

Abstract

PURPOSE: To enhance thermal efficiency by disposing means for delivering an article to be heated from one carrying path to the other carrying between upper and lower carrying paths. CONSTITUTION: A burner 2 is mounted on the side wall 1b of a furnace body 1 in which upper and lower carrying paths L1, L2 are formed independently along the left/right direction. A first walking beam 12 transports an article W to be heated intermittently from right to left carry-out section along the carrying path L1 and a third walking beam 32 transports the article W from the carry-out section of the carrying path L1 to the carry-in section of the carrying path L2. A second walking beam 22 transports the article W intermittently from left to right and from a lower room R1 to an upper room R2 sequentially and continuously. During the operation, high temperature heating gas is fed from the upper room R2 to the lower room R1 in the direction reverse to the transporting direction of the article W thus heat treating the article W.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a walking beam heating furnace that transports an object to be heated through cooperation between a stationary beam and a walking beam installed in the furnace.

[Prior Art] This type of heating furnace places objects to be heated on stationary beams lined up along the direction of transfer of the objects, and while the objects to be heated are intermittently fed by a walking beam. It is designed to be heat treated.

That is, the stationary beam is fixed at a fixed position in the furnace, and its upper surface forms a transfer path for the heated object extending along the direction of transfer of the heated object.
The walking beam is movably installed below the stationary beam and is configured to repeat a predetermined feeding operation. The walking beam repeats two operations: an operation in which it moves above the stationary beam and moves the object to be heated in the transfer direction, and an operation in which it moves below the stationary beam and moves in the opposite direction to the direction in which the object to be heated is transferred. The former operation lifts the object to be heated above the stationary beam and transports it a predetermined distance in the transport direction.

A conventional walking beam heating furnace has only one transfer path for the object to be heated within one furnace. That is, stationary beams are installed in a line, one transfer path is formed by the upper surface of the stationary beams, and the object to be heated is transferred and heat-treated along the one transfer path.

[Problems to be solved by the invention] As mentioned above, the conventional walking beam heating furnace has
Since there is only one transfer path for the object to be heated in one furnace, there are the following problems.

■The temperature of the exhaust gas discharged from the heating furnace is high. This is 1
This is because the exhaust gas in the heated atmosphere in the furnace is immediately exhausted, and the thermal efficiency is low due to the high temperature of the exhaust gas.

■In order to improve thermal efficiency, the heating furnace itself must be made longer, which increases equipment costs.

■If the heating furnace itself is simply made longer, the outer wall area will become larger and heat loss will increase. .

An object of the present invention is to solve such problems and provide a walking beam heating furnace that has good thermal efficiency and can keep the furnace length small.

[Means for Solving the Problems] The walking beam heating furnace of the present invention is fixed at a fixed position in the furnace and extends in the direction of transfer of the object to be heated, and has an upper surface serving as a transfer path on which the object to be heated is placed. a stationary beam that is movably installed below the stationary beam, and that moves above the stationary beam to move the object to be heated in the transfer direction; In a walking beam heating furnace that has a walking beam that repeatedly moves in the opposite direction to the direction in which the object to be heated is transferred, a partition wall that extends horizontally is provided in one furnace to divide the inside of the furnace into multiple sections in the vertical direction. One set of the stationary beam and the walking beam are installed in each of the plurality of division rooms to form mutually parallel conveyance paths, and between the lower conveyance path and the upper conveyance path. The present invention is characterized in that it is equipped with a transfer means for transferring the heated object carried out from one conveyance path to the other conveyance path.

[Function] The walking beam heating furnace of the present invention has a plurality of transfer paths for objects to be heated, which are arranged in one furnace so as to be located in the vertical direction, and a transfer means for transferring objects to be heated, which connects these transfer paths. By heat-treating the object while transferring it along a series of transfer paths, the thermal efficiency of the high-temperature gas for heating is increased, the heat treatment capacity per unit hearth area is increased, and the heat treatment capacity is increased relative to the heating capacity. This reduces the outer wall area of the heating furnace and increases thermal efficiency.

[Example] Embodiments of the present invention will be described below based on the drawings.

In the figure, l is a furnace body, and a burner 2 is installed on a side wall 1b so as to create a heating atmosphere in the furnace surrounded by a hearth 1a, a side wall Ib, and a ceiling 1c. Inside the furnace, two upper and lower transfer paths Ll and L2 are separately formed along the left and right direction in FIG. 2 (the front and back directions of the paper in FIG. 1).
The transfer path Ll transfers the heated object W from the right to the left in FIG. 2, while the transfer path L2 conversely transfers the heated object W from the left to the right in the same figure. It is designed to be transported.

The lower transfer path L1 is formed by a plurality of portal-shaped first stationary beams 11 fixed to the hearth 1a. That is, the portal-shaped stationary beam 11
The legs are fixed so as to be lined up along the transfer path Ll, and a rail 3 on which the object to be heated W is mounted is attached to an intermediate portion 11a (see FIG. 2). In the case of this embodiment, five stationary beams 11 are arranged in the width direction of the transfer path Ll (left-right direction in FIG. Three sets are arranged in the left and right direction).

Between these stationary beams 11, there is a first beam for intermittently feeding the heated object W placed on the rail 3 in the transfer direction.
Equipped with walking beam 12. That is, this walking beam 12 is formed in a gate shape like the stainless steel beam 11, and is connected to the transfer path Ll.
They are arranged on the hearth 1a so as to be lined up along the hearth 1a, and their legs are connected to the first drive mechanism 4 below the hearth 1a. In the case of this embodiment, four walking beams 12 are arranged in the width direction of the transfer path L1 and located between the stationary beams 11, and three walking beams 12 are arranged in the length direction of the transfer path L1.
Groups are lined up. Further, the first drive mechanism 4 operates the walking beam 12 as described later to move the object to be heated W.
This is because it causes intermittent feeding.

The walking beam 12 intermittently feeds the heated object W by repeating an ascending and descending operation and a reciprocating operation along the transfer path Ll at a predetermined timing. The walking beam 12 is
When viewed from the width direction of the transfer path L1, it moves in a trajectory as shown in FIG.

That is, the operation of moving upward from below the transfer path Ll and then moving in the transfer direction of the transfer path Ll (to the left in FIG. 3), and the operation of descending below the transfer path Ll and then moving in the transfer direction of the transfer path L1 The operation of moving in the direction opposite to the transport direction (to the right in FIG. 3) is repeated. Then, by the former operation, the object to be heated W is lifted above the stationary beam 11 and transferred by a predetermined distance in the transfer direction. Therefore, by repeating this operation, the walking beam 12
The object to be heated W is fed intermittently. A rail 3 is attached to the intermediate portion of the walking beam 12 on which the object to be heated W is placed, as in the case of the stationary beam 11.

On the other hand, the upper transfer path L2 is formed by a plurality of gate-shaped second stationary beams 21 fixed to the furnace wall 1b. That is, the legs of the gate-shaped stationary beams 21 are fixed to the horizontal beam 5 so as to be lined up along the transfer path L2. The horizontal beam 5 is placed in a fixed position between the left and right furnace walls 1b. In addition, the intermediate portion 21a of the stationary beam 21 is provided with a heated object W.
A rail 3 on which the is placed is attached. In the case of this embodiment, five stationary beams 21 are arranged in the width direction of the transfer path L1, and three sets of stationary beams 21 are arranged in the length direction of the transfer path L1. 21 is fixed by a total of six horizontal beams 5.

A second walking beam 22 is provided between the stationary beams 21 to intermittently feed the heated object W placed on the rail 3 in the transport direction. That is, like the stationary beam 21, the walking beam 22 is formed in a portal shape, and its legs are attached to the portal beam 6 so as to be lined up along the transfer path L2. Both ends of the portal beam 6 are bent downward and connected to a second drive mechanism 7.
Accordingly, the walking beam 22 together with the portal beam 6
is moved to perform a predetermined feeding operation.

In the case of this embodiment, the walking beam 22 is the transfer path L2.
They are attached to a total of six portal beams 6 such that four of them are lined up in the width direction and located between the stationary beams 21, and three sets of them are lined up in the length direction of the transfer path L2. There is.

The walking beam 22 intermittently feeds the object to be heated W by repeating an ascending and descending operation and a reciprocating operation along the transfer path L2 at a predetermined timing. The walking beam 22 is
When viewed from the width direction of the transfer path L1, it moves in a trajectory as shown in FIG.

This trajectory is exactly opposite to that of the walking beam 22 described above. That is, the operation of moving upward from below the transfer path L2 and then moving in the transfer direction of the transfer path L2 (to the right in FIG. 4), and the operation of descending below the transfer path L2 and then moving the transfer path L2. The operation of moving in the opposite direction (to the left in FIG. 4) is repeated. Then, by the former operation, the object to be heated W is lifted above the stationary beam 12 and transported by a predetermined distance in the transport direction. Therefore, the double king beam 22 intermittently feeds the heated object W by repeating such operations. A rail 3 is attached to the intermediate portion of the walking beam 22 on which the object to be heated W is placed, as in the case of the stationary beam 2.

Also, in the furnace, there is a first. A partition wall 10 is provided that is located between the second transport paths Ll and L2 and extends in the horizontal direction. This partition wall IO divides the interior of the furnace into two parts, into a lower chamber R1 where the first conveyance path L1 is located and an upper chamber R2 where the second conveyance path L2 is located. The partition wall 10 is cooled by cooling water passing through the partition wall 10, and the left side portion of the partition wall IO in FIG. 2 serves as a communication portion connecting the lower chamber R1 and the royal room R1. This communication part has a transfer means 31 for transferring the heated object W from below to above.
is in place.

The delivery means 31 is composed of a third walking beam 32 for vertical movement, which has a substantially inverted L2 shape in a side view (see FIG. 2), and a movement mechanism (not shown) for moving this walking beam 32. The walking beam 32 repeats the vertical movement and the reciprocating movement along the transfer path L2 at a predetermined timing. walking beam 3
The horizontal plate-like upper part 32a on the upper side of the transfer path L1. When viewed from the width direction of L2, it moves in a trajectory as shown in FIG. That is, the object W to be heated is placed on the transfer path Ll from below the transfer path L1, raised above the stationary beam 11, and then moved slightly in the transfer direction of the transfer path Ll (to the left in FIG. 5). Then, it rises above the transfer path L2, moves slightly in the transfer direction of the transfer path L2, and then descends below the transfer path L2, and places the object W to be heated on the stationary chili beam 21 of the transfer path L2. After placing it there, it moves slightly in the transfer direction of the transfer path Ll (to the left in FIG. 5), descends below the transfer path L1, and then moves in the opposite direction to the transfer direction of the transfer path Ll. The third walking beam 32 is
By repeating this operation, when moving up from below to above the transfer path L1, the object to be heated W on the discharge side of the transfer path L1 is lifted up, and when descending from above to below the transfer path L2, it is lifted up. One heated object W is placed on the carry-in side of the transfer path L2. Therefore, the first king beam 32 is
By repeating such operations, the heated object W on the carry-out side of the conveyance path Ll is delivered to the carry-in side of the conveyance path L2.

By the way, all the beams in the furnace 5,6°11.1
2.21 and 22.32 are forced to be cooled. The cooling means will be described later.

Next, the effect will be explained.

The first walking beam 12 repeats the operation of drawing a trajectory as shown in FIG. 3, thereby transporting the heated object W along the conveyance path L1 from the right side to the left side in FIG. Transfer intermittently. The third walking beam 32 is
By repeating the operation of drawing a trajectory as shown in FIG. 5, the object to be heated W is transferred from the carry-out section of the conveyance path L1 to the carry-in section of the conveyance path L2. Further, the second walking beam 22 intermittently transports the object to be heated W from the left to the right in FIG. 2 by repeating the operation of drawing a trajectory as shown in FIG. By performing these three transfer operations in a related manner, the object to be heated W is sequentially and continuously transferred to the lower chamber R1 and the upper chamber R2, and the object to be heated W is heat-treated in the meantime.

In the heat treatment, high-temperature gas for heating is sent into the furnace in a direction opposite to the direction in which the object to be heated W is transported. That is,
As indicated by arrow A in FIG. 2, high-temperature gas flows from the upper chamber R2 to the lower chamber R1, and the object W to be heated is heat-treated by this high-temperature gas. Therefore, the inside of the lower chamber R1 serves as a preheating zone to preheat the object to be heated W, and the upper chamber R2 serves as a heating and soaking zone. Preheating the cold material of the object to be heated W increases the thermal efficiency and lowers the exhaust gas temperature. By the way, the exhaust gas temperature at the furnace outlet of a conventional heating furnace, which is heat-treated in one chamber, was about 200°C or less, but it can now be reduced to 200°C or lower, and the thermal efficiency is increased accordingly. .

In addition, since the inside of one furnace body 1 is a two-stage type with a lower chamber R1 and an upper chamber R2, the length of the furnace body 1 is approximately halved compared to a single-stage type with only one chamber. It is possible to set it to . Further, since the outer wall area of the furnace body l is small compared to the heating capacity, heat loss is also small.

Next, the means for cooling the beam in the furnace will be explained.

As a cooling means, there is a water cooling method that circulates cooling water inside each beam, and FIGS. 6 and 7 show different examples of cooling means for the second stationary beam 21 and the horizontal beam 5. .

First, in the case of the example shown in FIG. 6, the horizontal beam 5 has a tubular shape, and cooling water is forced to cool the horizontal beam 5 through the inside thereof in the direction of the arrow in the figure. On the other hand, the stationary beam 21 has a tubular intermediate portion 21a and leg portions at both ends, and in each of the stationary beams 21, a cooling water introduction pipe 8 is connected to the leg portion on the right side in the figure. A cooling water discharge pipe 9 is connected within the left leg. For each stationary beam 21, the cooling water is supplied to the inlet pipe 8, the right leg, and the middle part 2.
The stationary beam 21 is forcibly cooled by passing through the leg on the left side of 1a1 and the discharge pipe 9 in this order.

On the other hand, in the case of the example shown in FIG. 7, the horizontal beam 5 is a double tube consisting of an inner tube 5a and an outer tube 5b, and one end of the outer tube 5b (the right end in the figure) is closed.

Further, the leg portions at both ends of the stationary beam 21 and the intermediate portion 21a are tubular, and the inside of the leg portion is communicated with the inside of the outer tube 5b of the horizontal beam 5. The cooling water introduced into the outer tube 5b of the horizontal beam 5 in the foreground in the figure cools each stationary beam 2 as shown by the arrow in the figure.
1, enters the inside of the outer tube 5b of the horizontal beam 5 at the rear through the front leg, the intermediate section 21a, and the rear leg, and then toward one end of the outer tube 5b (the right end in the figure). The stationary beam 21 is forcibly cooled by being discharged from the other end (the left end in the figure) of the inner tube 5a. Also, a part of the cooling water inside the outer tube 5b of the horizontal beam 5 on the near side flows toward one end of the horizontal beam 5 and is discharged from the other end of the inner tube 5a, so that the horizontal beam 5 is forcibly cooled. In addition, cooling water is introduced inside the outer tube 5b of the horizontal beam 5 on the rear side, and the horizontal beam 5
Forced cooling.

The number of transfer paths Ll and L2 in one furnace is not limited to two, one above the other, and three or more transfer paths may be formed in the vertical direction.

Further, the direction in which the object to be heated W is transferred by each transfer path is not specified in the same embodiment as described above, and can be set in an appropriate direction.

Furthermore, it is also possible to configure the walking beam drive mechanism in each transfer path as a common one.

Effects As described above, the walking beam heating furnace of the present invention has a plurality of transfer paths for the object to be heated in the vertical direction in one furnace, and these transfer paths are connected by means for transferring the object to be heated. Since it forms a series of transport paths, the following effects are achieved.

■The high-temperature gas sent into the furnace sufficiently heats the objects to be heated while passing through a series of transfer paths, which naturally lowers the exhaust gas temperature discharged from the furnace outlet, resulting in higher thermal efficiency. Become.

(2) Since the transfer path of the heated material is configured in multiple stages in the vertical direction within the furnace, a long transfer path can be formed without increasing the length of the furnace body.

■The outer wall area of the heating furnace is small compared to its heating capacity, so there is less heat loss.

[Brief explanation of the drawing]

The drawings are diagrams for explaining the invention in detail.
The figure is a cross-sectional view along the direction perpendicular to the transfer path of the heated object, FIG. 2 is a cross-sectional view along the line ■-■ in FIG. 1, and FIG. Figure 4 is the second
FIG. 5 is an explanatory diagram of the movement trajectory of the like-king beam, FIG. 5 is an explanatory diagram of the movement trajectory of the transport means, FIG. 6 is an explanatory diagram of an example of the beam cooling means, and FIG. 7 is an explanatory diagram of the beam cooling means. FIG. 2 is an explanatory diagram of an example. l... Furnace body, la... Hearth, 1
b...Side wall, lc...Ceiling, 2.
...Burner, 3...Rail, 4...
...First drive mechanism, 5...Horizontal beam, 6...Portal beam, 7...Second drive mechanism, 11...・First stationary beam, 12...First walking beam, 2
1...Second stationary beam, 22.
...Second walking beam, 31...
・Delivery means, 32...Third walking beam, R1...
... lower chamber in the furnace, R2 ... lower chamber in the furnace,
Ll... - first transfer furnace, R2... second transfer path, W... object to be heated.

Claims (1)

[Scope of Claims] A stationary beam fixed at a fixed position in the furnace and extending in the direction of transfer of the object to be heated, the upper surface of which serves as a transfer path on which the object to be heated is placed, and a lower side of the stationary beam. The stationary beam is moved above the stationary beam to move the object to be heated in the transfer direction, and the stationary beam is moved below the stationary beam to move in the opposite direction to the transfer direction of the object to be heated. In a walking beam heating furnace having a walking beam that repeatedly operates, a partition wall extending horizontally is provided in one furnace to divide the inside of the furnace into a plurality of vertically divided compartments, and each of the plurality of compartments has a , a pair of the stationary beam and a walking beam are provided to form conveyance paths parallel to each other, and between the lower conveyance path and the upper conveyance path, the heated object carried out from one of the conveyance paths is disposed. A walking beam heating furnace characterized by being equipped with a delivery means for delivering the material to the other conveyance path.