JPS6215431A - Automatic sampling device for dust coal - Google Patents

Abstract

PURPOSE:To give reproducibility to a locus of a nozzle and to sample dust coal automatically by connecting a device which turns the L-shaped nozzle reciprocatively, and moves it back and forth with a holding member which holds the L-shaped nozzle extending out outside a coal sending pipe easily attachably and detachably. CONSTITUTION:A sampling device is provided on a mounding seat 28 which holds the relative position with the coal sending pipe 1 where the dust coal is flowed. Then, a bracket 19 on a frame 13 is moved using a manual handle 21 and installed thereon fitting its central position on the center of the L-shaped nozzle 4. Then, the nozzle 4 is moved back and forth, and oscillated right and left from the position of a full line to the position of a dotted line in diagram driving a motor 18 for moving back and forth, and a motor 24 for oscillation by a controller. In this way, the reproducibility is given to the locus of the nozzle 4 and the reliability of a measured value is improved. Further, the programming is performed for every measured place and the optimum collection of the dust coal is made possible.

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to an apparatus for taking a sample to measure the fineness (particle size distribution) of pulverized coal, and a pulverized coal automatic system that can be easily and fully automated. This invention relates to a sampling device.

<Prior art and its problems> In recent years, boilers have increasingly been burning coal instead of oil. When using coal, small boilers often use stoker-fired coal, but large boilers often use pulverized coal. In order to use it as pulverized coal, it is necessary to crush the coal so that the fineness is below the specified level (passing 80 inches through a 200 mesh). If the grains of pulverized coal are coarse, the surface area per unit amount will be small, resulting in poor combustion and a large amount of unburned coal.

Therefore, it is preferable that the particles of pulverized coal be as fine as possible.

To measure this fineness, it is necessary to collect the pulverized coal that is supplied to the mill (coal crusher) and the boiler in the middle of the coal pipe using a specified method.

In ASME 4.2, sampling is performed at several points on two orthogonal radial axes (c, y) of the coal conveyance pipe 1 as shown in Figure 10, but in DIN, sampling is performed at several points on the two orthogonal radial axes (c, y) as shown in Figure 12. Type nozzle 4. The tip 5 of the nozzle 4 moves back and forth (front and back) as shown in FIG. 12 while swinging to the left and right as shown by the broken lines in FIG.
Sample by passing through. ASM in DIN
We have also verified the method of E.
The DIH method is said to be able to collect pulverized coal in a way that is more appropriate for the actual particle size distribution.

However, there is no suitable device on the market to carry out this method, and currently a person holds an L-shaped nozzle in their hand and uses a stopwatch and a scale to move the nozzle and collect the sample by feeling, but the reproducibility and sampling are difficult. There were problems and doubts about its reliability, and the trenches required a lot of manpower.

Therefore, the following equipment conditions are required for automatic sampling of pulverized coal.

(1) The duct must have an error in shape and a dimensional error in the relative position of the pedestal for the automatic sampling device to the sampling nozzle, so that the sampling nozzle can be easily and quickly held after the device is installed.

(2) The nozzle opening position of the sampling nozzle for collecting pulverized coal must follow the correct planned position trajectory so that the particle size distribution of the measurement results is reliable. In other words, it must be a device that automatically corrects positional errors due to inertia of the drive device.

(3) Also related to the above-mentioned item (2), it is necessary to have a memory and a device for issuing commands to change the reciprocating rotation and forward and backward speed of the L-shaped nozzle (sampling nozzle) in accordance with the sampling position.

(4) The amount of suction gas per unit time must be displayed correctly. The suction gas velocity must be equal to the gas flow velocity in the coal pipe.

(This concerns the reliability of the ratio [density] of pulverized coal to the unit gas amount.) Objective of the Invention The objective of the present invention is to eliminate the drawbacks of the prior art described above, and to install an L-shaped nozzle in the middle of a coal mining pipe. After installation, it is fully automated, enables highly reproducible and reliable movement, corrects variations in each coal mining pipe (there are large variations because they are made from cans), and allows changes in the trajectory of the nozzle tip. The object of the present invention is to provide a device that can easily perform optimal collection without an operator.

Summary of the Means> In short, the present invention is based on an automatic sampling device that controls and moves an L-shaped nozzle (a straight pipe nozzle may be used) with two variable rotor motors and an NO device, and the two motors have an interpolation function number. By set and toto? 4) The trajectory is reproducible and easy to change, the control box has memory and command functions to facilitate correction, and the speed can be varied at various points along the trajectory to enable optimal collection. .

Embodiment 1> Fig. 1.2 is a drawing showing an embodiment of the present invention 9, in which a frame 8 is slidably placed on a slide base 7, and a nozzle 11 is attached with a screw 9 and a nut 10. The frame 8 used is movable left and right (perpendicular to the plane of the paper), the slide frame 16 is movably mounted on the frame 8 by means of a guide bar 12, and the pole screw L14 and nut 15 are mounted.
Move the slide frame 1 back and forth onto the frame B. At one end of the ball screw 14 there is a gear 1.
6 and is engaged with the motor gear 17. The motor 18 holds the gear 17 and is mounted on the frame 8.

The slide bracket 19 is vertically and slidably suspended on the slide frame 16 and is moved up and down on the slide frame 13 by a screw 20 and a handle 21.

The size bracket 19 rotatably holds the sleeve 22 with a worm wheel, and at the same time holds the sleeve 22 with a worm wheel.
It holds a worm 26 which is engaged with the worm 2. The worm 23 is connected to a motor 24, and an encoder 25 is connected to the motor 24 by a coupling 26.

The sleeve 22 with worm foil has a notch 27 L
The mold nozzle 4 can be attached and held from the side without piercing.

The entire device above consists of a mounting seat 2 that maintains its relative position to the coal pipe 1.
It is installed on 8.

The longitudinal motor 18 and the swing motor 24 are driven by an NO control device (not shown).

A detailed explanation will be given below with reference to the drawings.

Figure 4 shows the nozzle 4 moving back and forth, and the rotation of the motor 1B is transmitted to the gear 16 of the ball screw 14 through the gear 17 attached to the motor 18.
The nut 15 that is engaged with the
- a frame 16 holding a frame 16 and a slide bracket 19 placed thereon; The sleeve 22 and the like move back and forth on the guide bar 12 (from the solid line position to the dotted line position).

FIG. 4 is a diagram showing how the nozzle 4 is swung left and right, and the motor 2
By repeating forward and reverse rotation of the worm 2 connected to the worm 26, the sleeve 22 with the worm foil engaged with the worm 26 swings, and the nozzle 4 fixed to the sleeve 22 swings between the two-dot chain line position and the dotted line position. It was designed to make you exercise. 1 (The drive device refers to the combination of a motor and a wheel, etc. that is driven by the motor.

Figure 5 is a diagram showing manual left and right positioning on the base 7. A moving frame 8 is rotatably fixed to a base 7, and by rotating a handle 11 and a screw 9, a nut 10 engaged with the screw 9 is moved, and the frame 8 holding the nut 10 moves from the solid line position to the dotted line position. This is what I did.

Figure 6 is a diagram showing manual alignment of the two bottoms.
) Bracket 19 sliding on frame 13 and frame 1
Handle 21 and screw 20 rotatably fixed to 6
By turning the nut (
The bracket 19 holding the nut moves from the solid line position to the dotted line position by moving the bracket 19 (not shown, the same structure as in FIG. 11).

Since the structure is as described above, use the manual handle 11° 21 to adjust the center position vertically and horizontally to align it with the center of the L-shaped nozzle 4, and then attach the L-shaped nozzle 4 and use the NO control device (
(not shown) and a back-and-forth movement motor 18 and a swing motor 24.
By driving the tip 5 of the nozzle 4, it is possible to automatically move the tip 5 of the nozzle 4 along the trajectory shown in FIG. The control will be explained in detail below.

When two motors are used to perform a synthesized movement, even if the speed ratio in the constant speed range is set to a constant ratio due to the difference in load inertia, the speed ratio changes in the acceleration/deceleration range, resulting in the path shown by the solid line in Figure 7. In reality, instead of passing through the dotted line route, the target reaches B' or B'' without reaching the desired destination B. In this case, the trajectory cannot be reproducible, so the movement of one of the two motors is In order to measure the reproducibility of the movement, an interpolation function is added to the control device so that the movement of the other side is calculated and the movement is passed along a predetermined path.

This also works effectively for changing the route (because it has a calculation effect), it is easy to change the trajectory.

A boiler that uses pulverized coal usually uses several burners instead of just one. Therefore, since the pulverized coal leaving the mill is divided into several coal feeding pipes and sent to several burners, it is necessary to measure the fineness of each coal feeding pipe. This means that there are several measurement points. However, since the coal pipes are manufactured from iron ore, they have large tolerances (in terms of diameter and shape), and it is difficult to always install this device in the same position for each coal pipe. This makes it necessary to modify the program for each coal pipe in accordance with the actual situation. To deal with this, a teaching function is added to the control device so that corrections can be made. The way to correct this is to issue a command to move to point C in Figure 8, and detect when the nozzle collides with the coal pipe by using an encoder (a device that encodes input signals to be suitable for the next device) and stepping motor to step out. If a collision is detected, the encoder output stops, but the stepping motor continues to be inputted while being out of step. The position at that time (detected by reading the pulse difference) is programmed. By repeating this process, the trajectory can be easily reproduced as shown in FIG. 14.

Furthermore, as shown in Figure 9, the flow velocity of pulverized coal in the coal feed pipe is faster in the center and slower in the wall, and as shown in Figure 16, when the nozzle is tilted, the suction port becomes an ellipse. . This means that optimal collection may be possible if the speed of the nozzle tip that follows the trajectory shown in FIG. 14 is not constant at each location. The control device of the present invention also makes it possible to easily change the speed partially at various points along the trajectory. The above-mentioned control is performed by memory and command signals from the command signal output device 29.

<Embodiment 2> In the previous description, the case where a stepping motor (pulse motor) was used was explained as an example, but the same effect can be obtained with an AC or DC servo motor with a built-in tachometer and encoder.

Furthermore, instead of detecting a collision by stepping out of step of the stepping motor, a proximity switch or the like can be used to detect the collision.

Effects> By implementing the present invention, there is no manual operation and the trajectory is reproducible, so the measured values are reliable. ), as it is an automatic device, it can be unmanned, it can be easily programmed according to the actual object at each measurement point, it is possible to obtain optimal sampling, and it is easy to select various trajectories. It has various effects such as:

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional view of a device according to a first embodiment of the present invention;
Fig. 2 is a view taken along the line A-A in Fig. 1, Fig. 6 is a drawing showing the longitudinal displacement of the device due to the drive of the motor 18, Fig. 4 is a surface measurement drawing showing the reciprocating rotation of the L-shaped nozzle, and Fig. 5 Figure 6 is a schematic diagram showing manual left-right displacement adjustment, Figure 6 is a schematic diagram showing manual front-rear displacement adjustment, and Figure 7 requires displacement correction due to the inertia of the drive device when reciprocating the L-shaped nozzle. An explanatory diagram of the correction of the trajectory, Fig. 8 is an explanatory diagram of the double movement caused by the opening end of the L-shaped nozzle coming into contact with the sending end pipe wall, and Fig. 9 is an explanatory diagram showing the flow velocity of pulverized coal in the coal feeding pipe. Figure 10 shows AS
Figure 11 is a longitudinal sectional view showing a conventional pulverized coal collection device connected to a coal feeding pipe; Figure 12 is a diagram showing the longitudinal displacement of a DIN L-shaped nozzle; The figure is a drawing showing the reciprocating rotation of the L-shaped nozzle, Fig. 14 is a plan view showing the locus of the tip opening of the L-shaped nozzle, and Fig. 15 is a drawing showing an example of the particle size distribution of pulverized coal in the coal conveyance pipe. It is. 1... Coal feed pipe 2... Straight pipe nozzle 6...
・Collection point 4...L-shaped nozzle 5...Nozzle tip opening 6...Tip opening locus 11.21...
Manual handle 22...Sleeve with worm wheel 29...Device for storing and outputting command signals Fig. 7 Fig. 9 Fig. 1 [1]

Claims (1)

[Scope of Claims] 1. In an apparatus in which an L-shaped nozzle is located in a coal-feeding pipe through which gas containing pulverized coal flows to collect pulverized coal and examine its particle size distribution, an L-shaped nozzle extending outside the coal-feeding pipe is used. A device having a holding member for easily attaching and detaching the nozzle, and connected to the holding member to cause the L-shaped nozzle to reciprocate and move forward and backward is connected and positioned on a pedestal connected to the coal feed pipe, A pulverized coal automatic sampling device characterized in that a driving device for forward and backward movement is connected to a device for storing memory and issuing command signals. 2. The memory section of the device for issuing memory and command signals stores interpolation operations for correcting the locus due to the inertia of the drive device, and also outputs commands for controlling the speed of reciprocating rotation and forward/backward motion corresponding to the sampling position. The automatic pulverized coal sampling device according to claim 1, characterized in that it stores information. 3. After the drive device connected to the holding member is installed on the pedestal connected to the coal feed pipe, it can be moved vertically, horizontally, and
The automatic pulverized coal sampling device according to claim 1 or 2, further comprising a manual adjustment mechanism that moves the holding member back and forth to bring the holding member to the L-shaped nozzle holding position.