JPH04187254A - Manufacture of dust collection electrode in duct type electrostatic precipitator - Google Patents

Abstract

PURPOSE:To enhance dust collection efficiency and to make pressure drop small by nearly keeping a gap equal to the width of a square pipe and parallel arranging a first prescribed number of the square pipe in the equal intervals so that the upper side faces thereof are made horizontal and forming a first step, and bringing the lower part corner of the square pipe into contact with the upper part corners of the respective square pipes of the first step and welding the same contact parts. CONSTITUTION:The interval equal to the width of a square pipe 1 is nearly kept and the prescribed number N of the square pipe is parallel arranged so that the upper side faces thereof are made horizontal and a first step (a) is formed. The lower part corner (m) of the square pipe 1 is brought into contact with the upper part corners (l) of the respective square pipes 1 of the first step (a). The contact parts are discontinuously welded (f). The prescribed number N+ or -1 is parallel arranged in the equal intervals so that the upper faces are made horizontal and a second step (b) is formed. The lower part corner (m) of the square pipe 1 is brought into contact with the upper part corners (l) of the respective square pipes 1 of the second step (b). The contact parts are discontinuously welded (f). The prescribed number N is parallel arranged in the equal intervals so that the upper faces are made horizontal and a third step (c) is formed. Hereinafter, the same operation as the second and third steps is performed repeatedly and the prescribed number M step is formed. Thereby the dust collection electrode of a duct type electrostatic precipitator is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for manufacturing a dust collection electrode for a duct type electrostatic precipitator.

[Conventional technology]

When collecting and removing particulate matter such as dust and mist from gas, it is recommended to use an electrostatic precipitator (hereinafter referred to as BP), which has advantages in terms of running costs such as high collection efficiency and low pressure loss. , is widely known as a powerful method. In recent years, there has been a great demand and expectation for even higher performance and compactness of EP, and as duct type P,
The inside of the duct is divided into multiple small ducts, a discharge electrode is placed in each small duct, and the wall of each duct is used as a collection pole, making each small duct into a small space (narrow spacing) for collecting dust. EPs featuring the following are attracting attention.

[Problems to be Solved by the Invention] The basic principle for achieving high performance and compactness of the duct type BP has already been explained in Japanese Patent Application Laid-Open No. 1-274852, and detailed explanation will be omitted. In duct-type EP, the inside of the duct is partitioned with multiple small ducts to create a smaller space (
It is essential to realize a dust collection space with narrow spacing, and higher manufacturing precision is required in terms of electrode positioning etc. than in normal BP.

The method of partitioning the duct by inserting a plurality of square pipes into the duct to form the small duct is used as a practical method. Regarding the positioning of the square pipe, as mentioned above, precision is required, and a conventional method for positioning and fixing the square pipe is to use a mounting bracket 19 as shown in FIG. 3, for example. but,
This mounting bracket supports the entire weight of the square pipe, so depending on the length of the square pipe, it tends to be a fairly large member.
In that case, there is a possibility that it becomes a large obstacle in the gas flow path, or that electric lines of force concentrate when a voltage is applied and have an unfavorable effect on charging. In addition, the method of fixing such a group of square pipes to the duct wall is often a problem. For example, the simplest method is to weld the parts of both ends of the square pipes that contact the inner surface of the duct, as shown in Figure 3. There is a method of combining in step 21. This method is convenient as it does not require additional mounting parts.

However, when there are a large number of square pipes or their length is long, a large welding area is required in order to support the entire weight of the square pipes with only the welded part, but the effective length of the weld is Since there is a restriction on the length of the contact between the end of the square pipe and the inner surface of the duct I, there is no choice but to increase the effective throat thickness of welding, and as a result, there are disadvantages such as having to increase the plate thickness of the square pipe. It was born. Further, by carrying out continuous welding with large leg lengths over almost the entire circumference of the inner surface of the duct, large welding distortions tend to occur, which also poses problems in terms of manufacturing accuracy.

[Means to solve the problem]

The present invention takes the following measures to solve the above problems.

That is, as a method for manufacturing a dust collection electrode for a duct-type electrostatic precipitator, (1) Arrange multiple square pipes in a duct, partition the cross section of the duct into small ducts in a grid pattern, and use the walls of these small ducts to In a duct-type electrostatic precipitator in which a bar-shaped discharge electrode is provided at the center of each of the small ducts in addition to serving as a collection electrode, the square pipes are arranged parallel to each other at equal intervals with a gap of approximately the width of the first predetermined pipe. The upper sides of the square pipes are arranged horizontally to form a first stage, the lower corners of the square pipes are brought into contact with the upper corners of the respective square pipes of the first stage, and the contact portions are welded, and second predetermined pipes are arranged in parallel and at equal intervals. The upper sides of the square pipes are arranged horizontally to form a second stage, the lower corners of the square pipes are brought into contact with the upper corners of the respective square pipes of the second stage, and the contact parts are welded, and the second stage is arranged in parallel and at equal intervals. A predetermined number of upper surfaces of 1 are arranged horizontally to form a third stage, and the same operations as in the second and third stages are repeated to form a third predetermined number of stages to form a grid-like small duct.

(2) In the above claim (1), welding is performed by intermittent welding.

(3) In claims (1) and (2) above, the third
After manufacturing a predetermined number of stages, a duct wall having a hole inscribed in the outermost surface of the square pipe and penetrating through the inscribed portion is arranged, and the contact portion of the through hole is welded.

(Operations) (1) The means described in paragraph (1) above operates as follows.

As a first stage, a first predetermined number (N) of square pipes are arranged in parallel and equally spaced with gaps of approximately the same width, with their upper surfaces horizontal.

As a second stage, a contact part is welded by bringing the lower corner of the square pipe into contact with the upper corner of each square pipe of the first stage,
The second predetermined number (N±
1) Arranged.

As the third stage, the lower corners of the square pipes in the second stage are brought into contact with the upper corners of the square pipes, and the contact portions are welded, and a predetermined number (N) are arranged in parallel and at equal intervals with the upper surfaces horizontal. be done.

Thereafter, the same operations as in the second and third stages are repeated until the third predetermined number (M) stages are reached and the process ends.

(2) By means of item (2) above, the corner contact portions of the upper and lower corner pipes are welded intermittently.

(3) After the Mth stage is completed by the means of paragraph (3) above,
The contact portion has a through hole, and a duct wall inscribed in the outermost surface of the square pipe is disposed, and the contact portion of the through hole with the outermost surface of the square pipe is welded.

In the manner described above, the square pipes are arranged and connected with high precision and efficiency, and a dust collection electrode of a duct type electrostatic precipitator is manufactured which has no protrusions that cause flow loss or charging obstruction.

〔Example] An embodiment of the present invention will be described with reference to FIGS. 1 and 2.

In FIG. 1, a predetermined number ('N) of rectangular pipes 1 are arranged parallel to each other with their upper surfaces horizontal, spaced apart by approximately the same width as a first stage a.

The upper corner of each square pipe 1 in the first stage a! The lower corner m of the square pipe 1 is brought into contact with the lower corner m of the square pipe 1, the contact portion is intermittent welded f, and a predetermined number (N±1) of pipes are arranged in parallel and at regular intervals with the upper surface horizontal to form two-pronged pipes.

The upper corner of each corner pipe 1 of the second stage! The lower corners m of the square pipes 1 are brought into contact with each other, and the contact parts are intermittent welded f, and a predetermined number (N) of pipes are arranged in parallel and evenly spaced with the upper surfaces horizontal, and the third stage C
is made.

Thereafter, operations similar to those for the second and third stages are repeated to create a predetermined number (M) of stages.

Note that the process may end at the second or third stage if necessary.

As described above, the grid-like small ducts of the duct type electrostatic precipitator are arranged with precision, have sufficient strength, and are manufactured without protrusions that may cause flow loss or charging problems. .

□ Also, as shown in Fig. 2, a duct wall 13 is arranged which is inscribed in the outermost surface g of the square pipe 1 of the small duct made above and has a through hole in the inscribed part. Square pipe outermost surface g
The contact area is welded.

As described above, the dust collection electrode of the duct type electrostatic precipitator is
It is manufactured with high precision, sufficient strength, and no protrusions that can cause damage or charging problems.

[Effect of the invention] □ As explained above, according to the present invention, a grid-like small duct with high precision and sufficient strength is formed, and the small duct can be attached to the duct wall with high precision and sufficient strength. It is fixed and the dust collection electrode of the duct type electrostatic precipitator can be changed.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of the structure of an embodiment according to claims 1 and 2 of the present invention, FIG. 2 is a perspective view of the structure of an embodiment according to claim 3 of the present invention, and FIG. The figure is an assembly diagram of a conventional duct type dust collector. 1.18... Square pipe, f... Intermittent welding. 13, 20...Duct wall, h...Through hole. 19...Mounting bracket.

Claims (3)

[Claims] (1) Arrange multiple square pipes in the duct, divide the cross section of the duct into grid-like small ducts, use the walls of these small ducts as dust collection poles, and place a rod-shaped pipe in the center of each small duct. In a duct type electrostatic precipitator provided with a discharge electrode, a first stage is formed by arranging a first predetermined number of the square pipes horizontally with their upper surfaces spaced parallel and at equal intervals with gaps of approximately the same width, and the first stage The lower corner of the square pipe is brought into contact with the upper corner of each of the square pipes, and the contact portion is welded, and a predetermined number of second upper surfaces are horizontally arranged in parallel and at equal intervals to form a second stage. The lower corner of the square pipe is brought into contact with the upper corner of each of the square pipes in the tier, and the contact portion is welded, and the first predetermined number of upper surfaces are horizontally arranged in parallel and at equal intervals to form the third tier. A method for manufacturing a dust collecting electrode for a duct type dust collector, characterized in that the same operations as in the second stage and the third stage are repeated to form a grid-like small duct as a third predetermined number of stages. (2) A method for manufacturing a dust collection electrode for a duct type electrostatic precipitator according to claim (1), characterized in that welding is performed by intermittent welding. (3) In claims (1) and (2) above, the third
After manufacturing a predetermined number of stages, a duct wall is arranged that is inscribed in the outermost surface of the square pipe and has a hole that penetrates through the inscribed part, and the contact part of the through hole is welded. Method for manufacturing dust collection electrodes for type electrostatic precipitators.