JPH0735893B2 - Soot blower device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial field of application> The present invention relates to a structure of a soot blower (soot blower) for removing dust attached to a water wall pipe of a boiler, particularly a coal-fired boiler.

<Prior art and its problems> In the conventional short-insertion soot blower device, when the valve opening operation of the medium reaches a predetermined position, the valve is fully opened to clean the water cooling wall pipe.
Depending on the type of coal, there was a lot of dust, and this phenomenon of soot blowing often caused water wall pipes to wear. Further, the injection medium nozzle of the soot blower is set so that the injection start from the nozzle is set at a position slightly inside the furnace from the water wall tube surface in the furnace, and the injection medium is concentrically injected. The nozzle is set to spray at a certain angle with respect to the wall surface of the water in order to improve the spraying effect, but at the beginning of spraying, the medium also contains moisture and the heat transfer surface is prone to wear due to the mixture of ash and moisture. It was

In such a conventional technique, the valve that supplies the injection medium is fully opened almost at the same time when the injection is started, and the heat transfer surface in the range of the medium injection trajectory of the nozzle is easily worn.

<Object of the Invention> An object of the present invention is to propose a soot blower structure for suppressing the phenomenon of wear and enhancing the cleaning effect in the soot blower for cleaning the heat transfer surface.

In addition, since the medium drain at the start of injection causes erosion, this is to be suppressed.

<Summary of Means> In short, according to the present invention, an outer tube of a soot blower is rotatably connected to a reduction gear case, a roller member connected to the gear case is brought into contact with an operation mechanism of a main valve of an injection medium, and Disclosed is a soot blower structure in which the structure of the cam is appropriate, the drain is discharged by slightly opening the valve, and the valve is fully opened slightly away from the wall surface of the water pipe.

<Means for solving the problem> When the valve for feeding the medium of the sootblower device is opened / closed, the injection nozzle comes to a predetermined position and the valve opening operation is started. By pressing to open the valve all at once. Therefore, when the medium is jetted from the jet nozzle, the medium is blown out together with the drain in the jetted medium, so that the heat transfer surface is easily worn. According to the present invention, as a method of suppressing the pressure at the start of injection, the cam mechanism is used to open the valve so that the pressure is suppressed at the beginning of injection and the drain is discharged at the same time. In order to prevent wear, the jet nozzle rotates and strokes simultaneously so that the jet medium spirally hits the heat transfer surface.

<Embodiment> FIGS. 4 and 5 are external views of a conventional short pull-out soot blower. The rotation of the motor 4'is transmitted to the screw tube 9 ', and the nozzle 2'moves forward (backward by the reverse rotation of the motor) by the screw processed on the outer surface of the screw tube 9'. The cam 7'has a structure which moves back and forth together with the screw shaft 9'while being restrained from rotating by the guide bar 10 '. When the cam 7'progresses above the valve 6 ', the trigger 8'is engaged with the cam 7'by the groove of the cam 7'as shown in FIG. By releasing the movement, the trigger 8'depresses the valve 6'downward by the cam 7 ', and fully opens the valve 6'at a stretch. As a result, the ejection medium is ejected from the ejection hole 3 of the nozzle 2'and is rotated on the spot.

1 and 2 are a plan view and a side view of a short slippage soot blower according to an embodiment of the present invention. The rotation of the motor 4 is transmitted to the screw shaft 14 by the chain 19 and the outer tube 12 is rotated by the gear 17 in the gear casing 16.
Further, the gear casing 16 is structured to move back and forth by the screw of the screw shaft 14.

The outer tube 12 rotates into the furnace side wall tube 20 by the rotation of the screw shaft 14, and enters the furnace side wall tube 20 to a certain position from the surface of the furnace side wall tube 20.
The roller 15 on the upper part of 16 contacts and rotates the cam 7. A trigger 8 is connected to the cam 7 via an arm 18. When the cam 7 rotates in accordance with the movement of the gear casing 16, the trigger 8 operates and pushes the valve 6 downward to fully open the valve 6.

The nozzle 2 jets the jetting medium from the jetting hole 3 while rotating the jetted medium, and when the nozzle 2 further advances, the nozzle 2 moves backward by the reverse rotation of the motor 4 and moves backward from the furnace side wall tube 20.

FIG. 3 is a plan view showing a state where the cam 7 is operated. The cam 7 is gradually opened until the contact surface becomes parallel to the outer tube axis center after the roller contacts, so that the drain discharge does not damage the water wall tube.

When the valve 6 is fully opened, the cam 7 is in the state shown in FIG.
Since the valve 6 is fully opened and does not rotate more than the outer diameter of the roller 15 when it is rotated by a certain angle, the valve 6 is held at the fully opened position even if the gear case sink 16 further advances. At the time of returning, the reverse process is performed, and the valve 6 gradually progresses from fully open to fully closed from the start of rotation of the cam 7 to the stop of rotation.

<Effects of the Invention> In the apparatus according to the present invention, the cam mechanism is operated until the valve is fully opened to suppress the injection pressure at the beginning of blowing, and the drain is discharged during this period. As a result, the drain is not discharged at a low pressure and the heat transfer surface is not worn.

On the other hand, at the same time, in the injection nozzle, the distance from the nozzle to the heat transfer surface is increased as the valve opening is fully opened, so that the pressure receiving surface from the injection medium is not subjected to extreme pressure. At the same time, since the trajectory of the jetting medium becomes spiral, the medium does not blow on the same surface, so the cleaning effect of the heat transfer surface is improved, but the wear due to ash is suppressed.

[Brief description of drawings]

1 is a plan view of a short pull-out soot blower according to an embodiment of the present invention, FIG. 2 is a sectional view taken along the line II of FIG. 1, FIG. 3 is a partial plan view showing the operation of a cam device, and FIG. Is a perspective view of a conventional short pull-out soot blower, and FIG. 5 is a rear view (viewed from the motor side) of the soot blower. 1 …… Short-plugging soot blower 2 …… Nozzle 3 …… Injection hole 4 …… Motor 5 …… Valve body 6 …… Valve, 7 …… Cam 8 …… Trigger, 12 …… Outer tube 15 …… Roller, 16 ...... Gear casing

Claims (1)

[Claims] 1. A soot blower for injecting a soot-blowing medium from an injection nozzle to clean a heat transfer surface, having a means for gradually opening a valve for supplying the soot-blowing medium according to the stroke of the injection nozzle. A special soot blower device.