JP2001271999A - Supply medium supply piping structure and supply method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent damage in a feeding passage due to fluctuation in flow speed of a supply medium. SOLUTION: This feeding piping structure for the supply medium is provided with a supply passage for the supply medium connected to a T-shaped header through a flow control valve and a branch passage branched off from the T-shaped header in two ways. In this structure, the flow control valve has a valve element rotating on a rotating shaft disposed in the radial direction of the pipeline and the angle of the rotating shaft to the center line of the branch passage ranges from 30 to 60 deg..

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of feeding a supply medium, and more particularly to a method of feeding the medium at an appropriate speed (flow velocity) to effectively reduce damage to a supply path. Hereinafter, a description will be given of an example in which combustion air and fuel gas used in a heating furnace for uniformly heating a steel material such as a billet to a predetermined temperature are used as a supply medium.

[0002]

2. Description of the Related Art As a furnace for heating a steel material such as a billet, for example, a walking beam type heating furnace 30 as shown in FIG. 4 is used. The steel material 21 is placed on the fixed beam 22 or the walking beam 23 in the heating furnace 30, and the walking beam 23 repeats the operation of ascending → forward → down → retreat, whereby the steel 21 is conveyed in the furnace length direction. You. After air for combustion is preheated to 650 ° C. by an air recuperator (not shown) as a heat exchanger, a plurality of air provided on the left and right side walls of the heating furnace 30 through a hot air pipe 8 as a hot air supply path. It is sent to the burner 10. Similarly, the fuel gas is also preheated to about 270 ° C. by a gas recuperator (not shown) and then passed through a gas pipe 9 which is a fuel gas supply path.
It is fed to a plurality of burners 10. In the burner 10, a burner 10a for heating the upper part of the heating furnace and a burner 10b for heating the lower part of the heating furnace are arranged on the side surface of the heating furnace along the furnace length direction.

[0003] A hot air supply piping system will be described from the upstream side. The hot air pipe 8 includes a main pipe 8a having one end connected to the above-described air recuperator, and a plurality of branch pipes 8b (only two pipes are shown in the drawing) branched from the main pipe 8a. The opposite side of the branch pipe 8b from the main pipe is a T-shaped header 11.
The T-shaped header is provided with a branch path 13 branched to the left and right side walls. In the example in the figure, three burners 10 are provided for one branch path 13.
(10a in the figure) is connected. As shown in detail in FIG. 5, the branch pipe 8b is provided with a flow control valve 15 at the entry side of the T-shaped header 11.

The fuel gas supply pipe system has the same structure as the hot air supply pipe system, and has a main pipe 9a having one end connected to the air recuperator and a plurality of branch pipes 9b branched from the main pipe 9a. (Only two pipes are shown in the figure), a T-shaped header 12 connected to the side of the branch pipe 9b opposite to the main pipe, and a T-shaped header 12
There is provided a branch path 14 branching from the side to the left and right side walls. In the example shown in the figure, three burners 10 are connected to one branch path 14. The branch pipe 9b is provided with a flow control valve 16 at the entry side of the T-shaped header 12, as shown in detail in FIG.

[0005] As described above, a total of six burners, three on the left and right furnace side walls, are connected to one branch pipe 8b, 9b for hot air and one for fuel gas, respectively. The flow rates of hot air and fuel gas are controlled by flow control valves 1
By making adjustments by 5 and 16, the combustion of the six burners can be controlled collectively. The group of six burners whose combustion is controlled collectively is defined as one section, and the sections are arranged in the furnace length direction so that the temperature in the heating furnace can be controlled by the position in the furnace length direction.

Incidentally, two rows of burners, ie, a heating furnace upper heating burner 10a and a heating furnace lower heating furnace burner 10b, are arranged on the furnace side wall. Only the fuel and hot air pipes and gas pipes connected to the
The fuel and hot air piping and gas piping connected to b are the same as those for the upper part of the heating furnace, and therefore description thereof is omitted.

[0007]

The branch path 13,
14 or an upstream supply route, that is, a hot air pipe 8,
The gas pipe 9 is usually made of SS400 pipe, and is lined inside as shown in FIG. 5 from the viewpoint of preventing corrosion at high temperature and reducing heat loss by heat insulation. As the lining material, a ceramic fiber having excellent heat insulation and workability is used, and a ceramic fiber block 17, a ceramic fiber sleeve 18, a ceramic fiber castable (a site where construction is difficult) 19 and the like are arranged according to the size of the pipe. In general, the ceramic fiber has a wind resistance specification of 30 m / cm with a ceramic fiber block from the viewpoint of strength.
S or less, 35m / S for ceramic fiber sleeve
The operation is performed under conditions that satisfy the wind resistance specifications, as set forth below.

However, in the lining material having the above-mentioned wind-resistant specifications, due to facility restrictions, the local distance of the medium passing through the pipe depends on the piping distance on the inlet and outlet sides of the flow control valve and the installation angle with respect to the branch path. The lining material is inevitably worn or dropped due to the high flow velocity and uneven flow, which requires enormous costs for repairs. The situation was inevitable.

Particularly, in a steel heating furnace, a supply pipe for hot air or fuel gas is usually arranged above the heating furnace as shown in FIG. 4, but a flow control valve is provided for the branch pipes 13 and 14 in the supply path. In consideration of the height of the heating furnace building, it is difficult to install the flow control valve at a position too high, that is, at a position far from the T-shaped header.
It will be installed on the entry side of the shape header. Further, when the above-described recuperator uses heat of exhaust gas from the heating furnace, the recuperator is disposed above the heating furnace. In this case, it is more difficult to install the flow control valve at a position far from the T-shaped header. Therefore, as shown in FIG. 5, the flow control valve is installed in the immediate vicinity of the entry side of the T-shaped header. In this case, however, there is a problem that a local increase in the flow velocity is likely to occur particularly due to the drift at the branch path position. .

An object of the present invention is to propose a new method capable of supplying a supply medium such as air or fuel gas while satisfying the wind resistance specification in the above-described path provided with an internal lining. It is in.

[0011]

SUMMARY OF THE INVENTION The present invention provides a supply medium having a supply medium supply path connected to a T-shaped header via a flow control valve, and a branch path branched from the T-shaped header in two directions. Wherein the flow control valve has a valve body that rotates about a rotary shaft disposed in the radial direction of the tube furnace, and the angle of the rotary shaft with respect to the center line of the branch path is A feed medium supply pipe structure characterized by being within a range of 30 to 60 °.

According to the present invention, there is provided a T-shaped header in which a supply medium in a pipe is branched right and left through a flow control valve provided with a valve element having a rotating shaft arranged along a radial direction of the pipe. In feeding to each branch path, the rotation axis of the valve body of the flow control valve is set at 30 to 60 ° with respect to the center line of the branch path.
Is a feed medium feeding method characterized in that the feed medium is fed while being held at an angle, and in the present invention, the feed medium is, in addition to combustion air used in a heating furnace for steel slabs, Fuel gas or the like is advantageously adapted. The angle of the valve body of the flow control valve is more preferably 40 to 50 °, and most preferably 45 °. In the present invention, the angle formed between the rotation axis of the flow control valve and the center line of the branch path is a cross-sectional view of the pipeline, that is, the rotation axis and the branch path based on the feeding direction of the supply medium passing through the pipeline. , The angle formed by the rotation axis and the center line of the branch path when the center line is viewed.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS According to the present invention, a valve body of a flow control valve disposed along a radial direction of a pipeline has an angle of rotation of 30 to 60 degrees with respect to a center axis of a branch path. With this configuration, the medium flowing into the branch path via the flow control valve does not locally increase or drift.

FIGS. 1 (a) and 1 (b) show the structure of a feed pipe structure according to the present invention. In the figure, reference numeral 1 denotes a supply path leading to a recuperator, 2 denotes a T-shaped header,
Reference numeral 3 denotes a flow control valve interposed between the supply path 1 and the T-shaped header 2. The flow control valve 3 has a rotary shaft 3a disposed along the radial direction of the pipeline 1, but is viewed in a sectional view of the pipeline. At an angle θ with respect to the central axis P of the branch path 4 shown in the example where the rotary shaft 3a is branched right and left by the T-shaped header 2.
And the valve element 3b opens and closes within a range of 0 to 90 degrees around the rotation shaft 3a according to the flow rate of the supply medium.

In the present invention, as shown in the drawing, in the sectional view of the pipeline 1, the rotary shaft 3a of the valve body 3b of the flow control valve 3 is shown.
Has an angle of 30 to 60 ° with respect to the center P of the branch path 4, so that the supply medium that has passed through the flow control valve 3 does not cause a local increase in flow velocity or drift, and satisfies the wind resistance specification. It flows smoothly through the branch path 4 while drawing a spiral in the folded state.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS When the angle θ of the valve body of the flow control valve is 45 ° (inventive example) and 0 ° (comparative example), when air is supplied at an air supply speed of 28 m / s, An analysis was performed on the air flow velocity at each position in the branch path. In addition,
The pipe inner diameter at the valve body position was 800 mm, and the distance from the rotation axis of the valve body to the center of the branch path was 1390 mm.

As a result, when air is supplied in accordance with the present invention, as shown in FIG. 2, although a local increase in flow velocity is very slight in the immediate vicinity of the outlet side of the flow control valve, the wind resistance in the branch path is small. The specifications are 30 m / s or less (see reference material), and the wear amount of the ceramic fiber is 5.
While it was confirmed that the value was 6 mm / year, it was confirmed to be 0 mm / year, whereas in the comparative example, the wind resistance was 35 m / s in the branch path where the ceramic fiber freeb was arranged as shown in FIG. A local increase in flow velocity of 50 m / s, well above the The angle θ of the valve body is 4
When the angle is shifted from 5 °, the maximum flow velocity in the branch path increases. However, it was confirmed that the wind resistance specification of 30 m / s or less can be achieved if the angle θ of the valve body is in the range of 30 to 60 °.

[0018]

According to the present invention, the supply medium can be fed in a state where the wind resistance specification of the path in which the lining is provided is satisfied. Damage can be suppressed, and the resulting shutdown of operations can be avoided, thereby greatly improving productivity. In particular, when applied to a steel heating furnace, equipment design that is excellent in energy saving can be performed.

[Brief description of the drawings]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an explanatory view of an embodiment of the present invention, in which (a) is a view showing a cross section of a feeding path, and (b) is a plan view thereof.

FIG. 2 is a diagram showing a flow velocity state when air is supplied according to the present invention.

FIG. 3 is a diagram showing a flow velocity state when air is supplied according to a conventional procedure.

FIG. 4 is a perspective view of a walking beam type heating furnace.

FIG. 5 is a diagram showing a main part of a feeding path of a walking beam type heating furnace taken out.

[Description of Signs] 1 supply path 2 T-type header 3 flow control valve 4 branch path 8 hot air pipe (supply path) 9 gas pipe (supply path) 10 burner 11 T-type header 12 T-type header 13 branch path 14 branch path 15 Flow control valve 16 Flow control valve 17 Ceramic fiber block 18 Ceramic fiber sleeve 19 Ceramic fiber castable

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Takaaki Ishikawa 1 Kawasaki-cho, Chuo-ku, Chiba City, Chiba Prefecture Inside the Chiba Works of Kawasaki Steel Corporation (72) Inventor Koichi Uemura 1 Kawasaki-cho, Chuo-ku, Chiba City, Chiba Prefecture Kawasaki F term in Chiba Works (reference) 3J071 AA02 AA04 BB14 CC12 DD14 FF05 4K034 AA03 BA08 CA01 DB08 EA15 GA18 4K050 AA01 BA02 CD02 EA06

Claims (3)

[Claims] 1. A supply medium supply piping structure having a supply medium supply path connected to a T-shaped header via a flow control valve, and a branch path branched from the T-shaped header in two directions. The flow control valve has a valve body that rotates about a rotation axis arranged in a radial direction of a pipeline, and an angle of the rotation axis with respect to a center line of the branch path is within a range of 30 to 60 °. A supply pipe structure for supplying a supply medium. 2. In feeding a supply medium in a pipe to respective branch paths of a T-shaped header that branches right and left through a flow control valve having a rotation axis arranged in a radial direction of the pipe, A method of feeding a supply medium, wherein the supply medium is supplied while maintaining a rotation axis of a valve body of the flow control valve at an angle of 30 to 60 degrees with respect to a center axis of a branch path. 3. The method for feeding a supply medium according to claim 2, wherein the supply medium is air or a fuel gas as a combustion aid used in a heating furnace such as a billet.