JPS62431B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a device for detecting an abnormality due to lump adsorption that occurs during slag suction in a vacuum suction type sludge remover.

During suction slag removal in vacuum suction type slag removers used for torpedo cars, hot metal pots, molten steel pots, etc.
Brick shavings floating in the slag and lumps of solidified slag may be attracted to the suction port of the suction head. When this happens, the flow path of the suction port of the suction head is constricted, causing an increase in the vacuum suction force and drifting, which sucks not only the slag, but also hot metal and molten steel when the slag is thin, causing damage to the inner surface of the tip of the suction head or the bent pipe. There is a risk of melting the inner surface or causing a steam explosion due to abnormal contact with cooling water.

Conventionally, abnormalities during lump adsorption have been detected by detecting changes in the source pressure or intermediate pressure of the vacuum pump, but it was clear that there was a difference between the pressure change during normal suction and the pressure change due to relatively small lump adsorption. It was difficult to tell the difference, and this was compensated for by constant visual inspection of the tip of the suction head.

SUMMARY OF THE INVENTION An object of the present invention is to provide a device that can accurately and immediately detect even abnormalities during adsorption of small lumps.

Generally, it is clear from Bernoulli's theorem that the static pressure of a fluid decreases downstream of an obstruction inserted in a flow path, that is, a restriction.

1/2ρv ² +ρgh+P ₁ = constant ρ: fluid density, v: flow velocity, g: power acceleration P: static pressure In the above equation, a decrease in the static pressure in the third term corresponding to the increase in fluid velocity in the first term occurs. do.

The present invention focuses on the fact that the mass adsorbed at the tip of the suction head of a vacuum suction type has a constriction function, and uses the above theorem to detect changes in the static pressure near the constriction point. This was done based on the knowledge that the accuracy is higher than that at a distant location, and a vacuum pressure measurement port for detecting the pressure immediately after squeezing, that is, at the tip of the suction head, is opened at the tip of the suction head on the inner surface of the suction head. There is a characteristic in the place where it is set up.

Next, the present invention will be explained using the drawings.

FIG. 1 is an overall explanatory diagram of a vacuum suction type slag remover equipped with the lump adsorption detection device of the present invention, where 1 indicates hot metal,
A ladle containing a molten material such as molten steel, 2 the molten material in the ladle, 3 slag floating on the molten material, 4 a suction head above the slag, 5 having the suction head at the tip. A suction tube, 6 is a slag separation tank with which the suction tube communicates, 7 is a steam condenser, 8 is a vacuum pump, 9 is a suction tip pressure measuring section of the suction head 4, 10 is the measuring section 9 and the vacuum pressure Impulse tube connecting converter 11, 1
2 is an amplifier connected to the vacuum pressure converter 11;
13 is an alarm setting device connected to the amplifier 12.

In the sludge removing machine shown in FIG. 1, a vacuum pump 8 maintains a vacuum state in a suction head 4 and a suction tube 5, sucks sludge 3 floating on the melt 2 in the ladle 1 into the suction tube, and After being conveyed to the slag separator 6 via the slag 5, the separated sludge is discharged.

The situation during suction work using the suction head is shown in Figures 2 and 3.

FIG. 2 shows a normal working situation, in which the slag 3 is suctioned smoothly by the suction head 4 without any hindrance. FIG. 3 is an explanatory diagram of the situation during lump adsorption. The lump-like slag 14 is adsorbed to the suction port of the suction head 4, which obstructs the suction of the slag 3 and increases the degree of vacuum (pressure decrease) in the suction head, causing the above-mentioned problems. occurs.

FIG. 4 is a diagram of the lump suction detection device of the present invention, in which a vacuum pressure measuring port 9 is opened at a location on the inner surface of the suction head 4 as close to the tip as possible. As mentioned above, the detection accuracy decreases as the position of the measurement port moves away from the tip of the suction head, so it is best to place it as close to the tip as possible.For example, if the length of the suction head is about 1000 mm, it is recommended to place it 100 mm from the tip. It is best to set it within

As shown in FIG. 1, a flexible pressure impulse tube 10 is connected to the measurement port 9 and is placed along the suction head.
Extend to a place where the temperature is not harsh (more than 5m),
It is connected to a vacuum pressure transducer 11, and the vacuum pressure transducer 11 converts the change in pressure at the tip of the suction head into an electrical signal.This electrical signal is received by an alarm setting device 13, and an alarm is issued depending on the classification of the signal.

Fig. 5 is an example of the vacuum pressure measured by the detection device of the present invention. Part A is the vacuum pressure near the tip inside the suction head when the tip of the suction head is open, and part B is 1/4 of the opening area of the suction head due to the adsorption of lumpy slag. When closed, part C is the same vacuum pressure when 1/2 is closed, and part D is the vacuum pressure when 3/4 is closed.

From this figure, 1/4 of the suction head opening area
The difference between the pressure when closed and the pressure when the opening is fully open is approximately
25mmHg, which is significantly different from the range of pressure change when the suction head is fully open. Therefore, if a situation occurs where at least 1/4 of the suction head opening area is closed, an alarm should be issued immediately. I can do it. In fact, by setting the electrical signal section immediately after the pressure change range when the valve is fully opened, it is possible to detect the adsorption of extremely small opening obstructions.

Note that some of the water droplets of spray water for cooling the slag may accumulate at the measurement port of the suction head, but a branch pipe should be installed between the measurement port and the impulse pipe between the vacuum pressure converter and a portion of the atmosphere to be sucked out. This allows water droplets to be blown away without causing large errors in vacuum pressure measurements.

Although the measurement may be made at one location at the tip of the suction head, lump adsorption can be detected more reliably by measuring the vacuum pressure at three locations at every 120° angle on the circumference.

According to this device, since the measurement port is installed at the tip of the inner surface of the suction head, it is possible to detect pressure changes at a location far away from the suction head. This has the effect that even abnormalities can be detected quickly. By detecting in this way,
Using known means, the suction head can be evacuated at a safe stage and the adsorbed lumps can be removed in a safe place when they are small, thereby preventing damage to the suction head, preventing steam explosions, etc. Furthermore, this has the effect of helping to ensure operator safety.

[Brief explanation of the drawing]

Fig. 1 is an overall explanatory diagram of a vacuum suction type sludge remover to which the device of the present invention is applied, Fig. 2 is a diagram of the normal suction action by the suction head, Fig. 3 is a diagram when similarly lumpy sludge is adsorbed; FIG. 4 is a detailed view of a suction head provided with a vacuum pressure measuring port of the present invention, and FIG. 5 is a diagram showing changes in vacuum pressure measured by the device of the present invention. 1: ladle, 2: melt, 3: slag, 4: suction head, 5: suction tube, 6: slag separator, 7: steam condenser, 8: vacuum pump, 9: suction tip pressure measuring section, 10: Impulse tube, 11: Vacuum pressure converter, 12: Amplifier, 13: Alarm setting device, 1
4: Clumped slag.

Claims (1)

[Claims] 1. A lump adsorption detection device for a vacuum suction type sludge remover, characterized in that a vacuum pressure measuring port is opened at the tip of the suction head on the inner surface of the suction head.