JP2003065944A - Method of detecting abnormality of transportation pipeline, method of monitoring condition and safety of transport, and abnormality detector - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable an article transportation facility, such as the pneumatic powder feeding facility, etc., of a converter to surely prevent the occurrence of a secondary accident or disaster caused by the leakage of a transported article or fluid by surely detecting in an early stage such a deficit as the perforation of a transport pipeline, such as a pneumatic pipeline, liquid feed pipeline, etc., caused by wear, corrosion, etc., by means of a relatively simple inexpensive device. SOLUTION: Double-pipe abnormality detectors 20 for transportation pipeline are installed to the transporting direction changing sections 5a, 5b, and 5c which are the specific wearing sections of the pneumatic pipeline 5 of the pneumatic powder feeding facility. The pressure P2 between the inner pipe 21 and outer pipe 22 of each detector 20 is preset to meet P3 >P2 >P1 (wherein, P3 is the internal pressure of the pipeline 5 during pneumatic feeding and P1 is the internal pressure of the pipeline 5 while the pneumatic feeding is stopped) and always monitored. When the measured P2 value rises (P2 becomes equal to P3 during pneumatic feeding or drops (P2 becomes equal to P1 while pneumatic feeding is stopped), it is discriminated that the pneumatic feeding pipeline is perforated by corrosion.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for detecting an abnormality in a transportation pipeline such as a pneumatic pipeline or a liquid pipeline, a transportation status safety monitoring method, and an abnormality detection apparatus, for example, in a steel refining process. -It is effectively applied to powder transportation equipment used for technology to remove harmful substances in molten steel, and powder transportation equipment for dephosphorization, desulfurization, desiliconization, etc.

[0002]

2. Description of the Related Art FIG. 3 shows an example of powder feeding equipment used in a steel refining process. FIG. 3 is a powder pneumatic equipment used for performing hot metal dephosphorization (hereinafter referred to as dephosphorization) in a converter, and mainly includes a dust collector 3 that stores powder from the powder receiving section 1. Storage tank 2 provided with the powder, a powder feeding pipe 4 for feeding the powder in the powder receiving portion 1 to the storage tank 2, and a powder for feeding the powder in the storage tank 2 to the powder blowing lance 6 of the converter. It is composed of a body air delivery pipe 5.

[0003] The powder care delivery carrier gas, the cost is cheaper, and safety management on the problem with little inert gas (N _2,
Ar, CO ₂ etc. are used. In FIG. 3, a carrier gas supply pipe 7 is connected to the bottom of the storage tank 2, and the powder in the tank is blown by the powder gas feeding pipe 5 by N ₂ or the like blown therein.
Is being introduced to.

In the powder pneumatic pipe 5 in which the powder is pumped by a carrier gas such as N ₂ , a portion such as a curved pipe that changes the pneumatic direction is a place where collision wear is likely to occur, Specifically, as shown in FIG. 4, wear countermeasures such as build-up welding 50 and liner welding using wear-resistant steel of high Cr steel, or attachment of ceramic chips or ceramic rings have been implemented to deal with the problem.

Further, in recent years, there has been disclosed a method of carrying out hot metal degassing P in a converter using such a powder pneumatic equipment.
No. 3,115,23 and JP-A No. 11-172313. In these proposals, CaO powder or CaO powder and Al ₂ O
It is stated that the use of oxygen is required as a powder carrier gas for a mixture of _three powders. In FIG. 3, an O ₂ carrier gas supply pipe 8 is connected to the most upstream side of the powder feeding pipe 5, and oxygen is mixed as a carrier gas.

[0006]

In such powder pneumatic equipment, the most difficult technically in terms of equipment is the estimation of the perforation life due to wear of the pneumatic piping. On the other hand, on the other hand, depending on the type of gas for powder transportation, how to ensure safety in the event of a wear hole punching problem, and how to prevent wear hole punching problems before they occur In comparison with cost, equipment technology is being pursued with a balance between safety assurance and cost reduction.

However, in reality, it is very difficult to predict or estimate this wear hole drilling timing, and even if it is predicted, the actual situation is that it does not work. That is, the life of the pneumatic piping is such that the thinning of the pneumatic piping due to collision wear of the powder progresses, leading to perforation. The factors differ depending on the properties of the powder, but the specific gravity, hardness, The main factors are the shape, size, concentration, speed, etc., and the flow velocity (determined by the pressure and flow rate) of the powder transport gas. If any one of these factors is different, it will greatly affect wear. It is difficult to estimate the life on the desk.

Therefore, at present, even if wear holes are formed,
Secondary disasters rarely occur N ₂Inert gas such as gas
Is used as a carrier gas. But the above
As disclosed in Japanese Patent Application Laid-Open No. 11-172313,
As a method of efficiently refining in a converter,
The most important thing is to transport the powder using oxygen and blow it into the converter.
It is good. However, if oxygen is used as a carrier gas,
In this case, the occurrence of collision wear hole punching of pneumatic equipment immediately causes "fire / explosion".
There is a risk of inducing secondary disasters such as "departure".

The present invention has been made to solve the above-mentioned problems, and in object transportation equipment such as powder pneumatic equipment of a converter, it is possible to reveal wear holes in transportation piping such as pneumatic piping and liquid feeding piping. Defects such as pits and corrosion holes can be reliably detected early by a relatively simple and inexpensive device, and secondary accidents and disasters due to leakage of transport objects and transport fluids can be reliably prevented. It is an object of the present invention to provide a transportation pipe abnormality detection method, a transportation condition safety monitoring method, and an abnormality detection device that can be used.

[0010]

Means for Solving the Problems In order to achieve the above-mentioned object, the inventors of the present invention have conducted various studies and experiments, and have been able to detect the perforation phenomenon of pneumatic piping due to collision wear of powder. By developing a "double-pipe pneumatic delivery pipe" called a "wear detection pipe" and attaching it to a specific part of the pneumatic delivery pipe and constantly monitoring it, we were able to quickly detect defects such as wear holes. Furthermore, a transportation status safety monitoring system was completed to perform a secondary trouble prevention countermeasure operation using the "double pipe pneumatic piping".

A first aspect of the present invention is a method for detecting an abnormality in a transportation pipe for transporting an object, which detects a defect in the transportation pipe at an initial stage by constantly monitoring the state of wear in the transportation pipe. This is a characteristic method for detecting abnormalities in transportation piping.

In the present invention, the transportation pipe for transporting the object is powder pneumatic transportation pipe or other pneumatic transportation liquid or liquid transportation pipe. By measuring the internal pressure change at a specific site with a pressure detector, it is constantly monitored, and when an internal pressure change occurs, it is determined that the transport piping is defective.

A second aspect of the present invention is a method for detecting abnormality in a transportation pipe for transporting an object, wherein an arbitrary portion of the transportation pipe is a double pipe in which a space between the inner pipe and the outer pipe is sealed, and the inner pipe is It is a method for detecting abnormality in a transportation pipe, characterized by detecting a defect in the transportation pipe at an initial stage by continuously measuring an internal pressure between the outer pipe and the outer pipe.

According to the second aspect of the present invention, a "double pipe type transportation pipe", which is a "wear detecting pipe", is provided at an arbitrary portion of the transportation pipe, and an inner pipe of the "double pipe type transportation pipe" is provided. The internal pressure P ₂ between the outer pipe and the outer pipe is continuously measured, and the internal pressure P ₂ is compared with the internal pressure P _{1 of the} transportation pipe (when transportation is stopped) / P ₃ (during transportation) to monitor the internal pressure P _2. When the change in the pressure P ₂ occurs, it is determined that the transportation pipe is defective.

According to a third aspect of the present invention, in the abnormality detecting method according to the second aspect, by filling a gas or a liquid between the inner pipe and the outer pipe of the double pipe, the inner pipe of the double pipe is formed. A method for detecting abnormalities in transportation pipes, characterized in that the internal pressure between the outer pipes is controlled to a constant value, this internal pressure is continuously measured, and when this measurement value fluctuates, it is determined that the transportation pipes were missing. is there.

According to the third aspect of the present invention, a gas (an inert gas such as N ₂ ) or a liquid is filled between the inner pipe and the outer pipe of the double pipe, and the internal pressure P ₂ is adjusted according to the fluctuating transport amount. The internal pressure P ₂ is adjusted or fixed to a set value when the transportation amount is constant, and the internal pressure P ₂ is remarkably changed (increased or decreased) when the inner pipe is damaged. .

According to a fourth aspect of the present invention, in the abnormality detecting method according to the second or third aspect, the pressure in the transportation pipe when the object is not transported is P _1, and the inner pipe and the outer pipe of the double pipe are set. the internal pressure between the tubes and P _2, P ₂ such that P _2> P ₁
Is controlled and it is determined that the transportation pipe is defective when P ₂ becomes lower than the control value.

According to claim 4, detection of a defect at the time of stopping transportation
And the pressure P in the transportation pipe when transportation is stopped₁Is
Atmospheric pressure (gauge pressure = 0) or pressure close to it,
P₂Is set to a pressure higher than atmospheric pressure, and the inner tube is
P₂= P₁And the measured value P₂Drops
To do so. P₂And P₁Is constantly measured and compared, P ₂
= P₁If so, it may be determined that a defect has occurred, and P₂
Always measure only the measured value P₂Is the set value P₁Descend to
Then, it can be determined that a defect has occurred.

According to a fifth aspect of the present invention, in the abnormality detecting method according to the second, third or fourth aspect, the pressure in the transportation pipe during the transportation of the object is set to P _3, and the inner pipe and the outer pipe of the double pipe are set. the internal pressure between the P _2, by controlling the P ₂ such that P _3> P _2, transportation pipeline when the P ₂ is higher than the control value, characterized in that it is determined that the missing transport This is a method for detecting abnormalities in piping.

Claim 5 is a case of detecting a defect during transportation, the pressure P ₃ in the transportation pipe during transportation is high, and P ₂ is set to a pressure lower than P _3. Every
Due to the perforation of the inner tube, P ₂ = P ₃ and the measured value P
Allow ₂ to rise. The pressure P ₃ is a pressure that increases in proportion to the transport amount per unit time, and the internal pressure P ₂ is adjusted so that P ₃ > P ₂ according to the fluctuating transport amount, or the transport amount is When constant, the internal pressure P ₂
Fix to a set value that satisfies ₃ > P ₂ . Also in this case, P
₂ and P ₃ are constantly measured and compared, and when P ₂ = P ₃ ,
It may be determined that a defect has occurred, or if only P ₂ is constantly measured and the measured value P ₂ rises to the set value P ₃ , it can be determined that a defect has occurred.

[0021] Claim 6 of the present invention includes claims 1, 2, 3,
In the abnormality detection method according to 4 or 5, the portion that detects a defect in the transportation pipe is a direction conversion unit that changes the transportation direction of the transportation pipe.

The sixth aspect is a case where the location for detecting a defect of the transportation pipe, that is, the installation position of the pressure detector or the "double pipe type transportation pipe" is limited. That is, in the transportation system, the parts that cause collision wear due to powder or fluid are
It is almost decided from theoretical and empirical ones. That part is the direction change part (curved part) where the pipe changes from the guide function of transportation to the function to control the direction of transportation, and a pressure detector and "double pipe type transportation pipe" are installed here. .

Claim 7 of the present invention includes claims 1, 2, 3 and
When a defect in the transportation pipe is detected by the abnormality detection method described in 4, 5, or 6, an alarm is issued, the operation of the transportation system equipment is automatically stopped, and the inside of the transportation pipe is purged. It is a monitoring method.

According to the present invention, when an abnormal change in the internal pressure is detected by a pressure detector, a "double pipe type transportation pipe" or the like, an alarm is given to an operator of the equipment, for example, a powder feeding equipment in a converter. Then, stop powder transportation, block shutoff valves related to operation and disaster prevention, send inert gas such as N ₂ into the pneumatic piping, and purge internal powder and carrier gas such as oxygen. A series of operations are automatically performed to prevent the occurrence of secondary accidents and disasters.

An eighth aspect of the present invention is an apparatus for detecting an abnormality in a transportation pipe for transporting an object, comprising an inner pipe and an outer pipe, the inner pipe being connected to the transportation pipe so as to communicate therewith, and the inner pipe and the outer pipe. An abnormality detection device for a transportation pipe, comprising: an abnormality detection pipe having a sealed state between pipes; and a pressure detector for detecting an internal pressure between an inner pipe and an outer pipe.

[0026] Claim 8 is a specific structure of the "double pipe type transportation pipe" which is the "wear detecting pipe", and the internal pressure P between the inner pipe and the outer pipe of the double pipe is detected by the pressure detector. ₂ detected,
The measured value is output to the computer with a wired or wireless transmitter. P ₂ and P ₁ · P ₃ are constantly measured and compared, P ₂ =
When P ₁ and P ₂ = P ₃ , it may be judged that a defect has occurred. If only P ₂ is constantly measured and the measured value P ₂ falls or rises to the set values P ₁ and P ₃ , the defect is detected. It can also be determined to occur.

According to a ninth aspect of the present invention, in the abnormality detecting device according to the eighth aspect, there is provided a supply pipe for supplying a gas or a liquid between the inner pipe and the outer pipe. It is a device.

According to the ninth aspect, by supplying a gas (an inert gas such as N ₂ ) or a liquid between the inner pipe and the outer pipe, the internal pressure P ₂ between the inner pipe and the outer pipe is P ₃ > P ₂ > P
It is designed to be controlled so as to satisfy ₁ .

A tenth aspect of the present invention is the eighth or ninth aspect.
In the anomaly detection device described in (1), the anomaly detection pipe is a transportation pipe anomaly detection device characterized by comprising a curved pipe portion and a straight pipe portion connected to a downstream side of the curved pipe portion. .

The tenth aspect of the present invention is "double pipe type transportation pipe".
Is installed in the transport direction changing portion (curved portion) as the wear specific portion, and is abnormal from the bend pipe portion of the bend pipe of 15 ° to 180 ° and the straight pipe portion of a certain range that passes through the bend pipe portion. Configure a detector tube so that wear holes can be reliably detected.

According to an eleventh aspect of the present invention, in the abnormality detecting device according to the tenth aspect, when the radius of curvature of the curved pipe portion is R, the length of the straight pipe portion is 0.5R to 1.0R. An abnormality detection device for transportation piping, which is characterized in that

That is, if the length of the straight pipe portion is shorter than 0.5R, there is a high possibility that the defect cannot be found, and it is empirically unlikely that the defect will exceed 1.0R and the defect will occur.
The length of the straight pipe part is 0.5R because it costs too long.
It is preferable to be set to 1.0R.

In the present invention having the above-mentioned structure, the pressure detector constantly monitors the internal pressure change at a specific worn portion of the transportation pipe or the abnormality detection device of the "double pipe type transportation pipe" is used as the transportation pipe. The internal pressure P between the inner pipe and the outer pipe of the double pipe is arranged at the transport direction changing portion, which is the specific wear portion of
₂ to P ₃ (internal pressure of the transportation pipe during transportation)> P ₂ > P
_{It is} set so as to satisfy ₁ (the internal pressure of the transport pipe when the transport is stopped), and the internal pressure P ₂ between the inner pipe and the outer pipe is constantly monitored, so that the pneumatic pipe, the liquid pipe, etc. Defects such as wear perforation and corrosion perforation of the transportation pipe can be detected early and reliably by a relatively simple and inexpensive device regardless of whether it is being transported or not.

That is, in the case of the "double pipe type transportation pipe", the internal pressure P ₂ between the inner pipe and the outer pipe is set so as to satisfy P ₃ > P ₂ > P ₁ and the transportation is carried out. When a hole is formed in the inner pipe of the double pipe, the space between the inner pipe and the outer pipe communicates with the inner pipe, that is, the transportation pipe, so that the internal pressure P ₂ between the inner pipe and the outer pipe.
= P ₃ (internal pressure of the transportation pipe during transportation) and the measured value P ₂ rises, so that it can be determined that the hole is perforated. In addition, if the wear-reducing pipe part is cracked due to some reason (thermal expansion / contraction, natural force such as earthquake) while not being transported, internal pressure P ₂ between the inner pipe and the outer pipe =
It becomes P ₁ (internal pressure of the transportation pipe when transportation is stopped) and the measured value P ₂ is lowered, so that it can be determined that the hole is perforated.

Further, when the abnormality detecting device for the double pipe type transportation pipe is used, since the double pipe is composed of the inner pipe and the outer pipe, there is an outer pipe even if the inner pipe has a hole. Therefore, the powder, the fluid, etc. do not leak, and the transportation can be continued.

Further, as described above, the perforation of the transportation pipe is quickly caught, and an alarm is given to the operator of the equipment,
By automatically stopping the operation of the transportation system equipment and purging the inside of the transportation pipe, it is possible to reliably prevent a secondary accident / secondary disaster due to leakage of a transportation object or a transportation fluid.

[0037]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described below based on illustrated embodiments. This embodiment is an example applied to a powder pneumatic equipment used for carrying out hot metal P removal in a converter. FIG. 1 is a system diagram showing an example of powder feeding equipment to which the present invention is applied. FIG. 2 shows a specific example of the abnormality detection device used in the present invention.

As in the case of FIG. 3, the powder pneumatic equipment of FIG. 1 mainly comprises a powder receiving section 1, a storage tank 2 with a dust collector 3,
From the powder pneumatic piping 4 for feeding the powder in the powder receiving section 1 to the storage tank 2 and the powder pneumatic piping 5 for feeding the powder in the storage tank 2 to the powder blowing lance 6 of the converter. A carrier gas supply pipe 7 of N ₂ or the like is connected to the bottom of the storage tank 2, and an O ₂ carrier gas supply pipe 8 is connected to the most upstream side of the powder feeding pipe 5.

A base end shutoff valve 10 is provided at the base end of the powder feeding pipe 5 on the storage tank 2 side, and a tip shutoff valve 11 is provided at the tip end on the powder blowing lance 6 side. There is.
The carrier gas supply pipe 7 for N ₂ or the like is provided with a shutoff valve 12, a pressure adjusting valve 13 and the like. The O ₂ carrier gas supply pipe 8 is provided with a shutoff valve 14, a flow rate adjusting valve 15, a flow rate control orifice 16 and the like. Further, the upstream side of the carrier gas supply pipe 7 for N ₂ or the like and the downstream side of the cutoff valve 14 of the O ₂ carrier gas supply pipe 8 are connected by a bypass pipe 18 having a cutoff valve 17, and a powder feeding pipe. An inert gas such as N ₂ can be supplied into the chamber 5 in place of O ₂ .

In the powder pneumatic equipment having the above-described structure, as shown in FIG. 1, the abnormal parts according to the present invention are provided in the direction changing portions 5a, 5b, 5c in which the pneumatic direction of the powder pneumatic piping 5 changes. A detection device 20 is provided.

As shown in FIG. 2, the abnormality detecting device 20 is a "double pipe type air feeding pipe" which is a "wear detecting pipe".
Further, there are a 15 to 60 ° bend pipe type used for the direction changing portion 5a, a 90 ° bend pipe type used for the direction changing portion 5b, a 180 ° bend pipe type used for the direction changing portion 5c, and the like. It is composed of an inner pipe 21 and an outer pipe 22 having a shape corresponding to the conversion portions 5a, 5b, 5c.

The inner pipe 21 is a pipe having the same diameter as the powder feeding pipe 5, and the outer pipe 22 is a pipe having an inner diameter larger than the outer diameter of the inner pipe 21. By attaching the connection flanges 23 to both ends of the double pipe by welding or the like and closing the openings, a sealed space 24 having a ring-shaped cross section is formed between the inner pipe 21 and the outer pipe 22. By bolting the connection flange 23 to the connection flange 25 of the powder feeding pipe 5, the wear detecting air feeding pipe 20 can be integrated with the powder feeding pipe 5 to feed the powder, and as will be described later. It is possible to detect wear hole drilling at an early stage.

The outer tube 22 of such a wear detecting pneumatic tube 20
Further, a fluid supply pipe 30 capable of supplying a gas or liquid such as N ₂ into the sealed space 24 and a pressure detector 31 for detecting the pressure P ₂ inside the sealed space 24 are connected. The fluid supply pipe 30 is provided with an opening / closing valve 32 and a one-touch joint 33. The pressure detector 31 has a wired or wireless transmitter 34, and is connected to the outer pipe 22 via an opening / closing valve 35. It should be noted that a wireless transmitter can be installed and monitored in places where a wired transmitter cannot be environmentally attached in an important part.

Here, the pressure in the powder pneumatic piping 5 during pneumatic transportation
P₃Increases in proportion to the amount of powder delivered per unit time.
Since the pressure fluctuation range is relatively large,
To P ₃> P₂> P₁(Inside the powder pneumatic piping 5 when pneumatic transportation is stopped
Pressure P in the sealed space 24 so that the pressure P₂
To control. When using a fixed fixed amount
, P₃If the fluctuation of
Pressure P₂Can be set to a constant pressure.

The pressure P ₃ in the powder air feeding pipe 5 during air feeding and the pressure P ₁ in the powder air feeding pipe 5 at the time of stopping air feeding are set to appropriate values for the powder air feeding pipe 5 shown in FIG. Position and wear detection pneumatic tube 20
A pressure detection transmitter can be installed in the inner tube 21 of the device for measurement.

Measured pressure P₁, P₂, P₃Is shown
Not entered on the computer, P ₂And P₁Or P₃
Is constantly compared, P₂= P₁(When air is stopped) or P₂
= P ₃When it is (in transit), it is judged as perforated as described later.
Security measures are implemented as described below. Note that P
₁Or P₃Is not measured, but is set or measured in advance.
The measured value P₂And compare the set value
It can also be judged as perforated.

As shown in FIG. 2, the wear detecting pneumatic tube 20 has a curved pipe portion (15 ° to 90 ° to 180 ° bend pipe) 40 having a radius of curvature R and a downstream side of the curved pipe portion 40. Since the straight pipe portion 41 is integrally continuous and the curved portion of the pipe that is most likely to be damaged and the specific wear portion in a certain range that passes through this portion are used as the defect monitoring portion, the defect can be reliably detected. To do.

The length of the straight pipe portion 41 is 0.5R to
It is preferably 1.0R. That is, if the defect monitoring region is shorter than 0.5R from the downstream side of the curve, the possibility that the defect cannot be found increases. Also, the wear detection pneumatic tube 2
A length of 0 is preferable because the monitoring site increases as the length becomes longer, but the length of the straight pipe portion 41 is set to 1.0R or less in consideration of the place and the cost where defects frequently occur.

Further, the fluid supply pipe 30 and the pressure detector 3
1 is preferably installed on the upstream side of the wear detecting pneumatic tube 20 and inside the curve. This is to prevent the pressure detector and the like from being destroyed by the effluent at the time of pipe deficiency because the occurrence frequency of deficiency is high outside the curve and the deficiency is likely to increase toward the downstream side.

[A] Detection of perforation of wear hole (1) Generally, when pneumatic design is carried out, the pneumatic pressure P ₃ is 0.1 MPa to 1 MPa, although it depends on the preconditions. The pressure P ₁ during the air supply stop is generally atmospheric pressure (gauge pressure =
0) or a pressure close thereto, which is 0 to 0.01 MPa. Therefore, the pressure setting of the wear detection pneumatic tube 20 that is constantly monitored, that is, the pressure P ₂ in the sealed space 24 is P _{3 to} P _3.
It is best to control during ₁ . This P ₂ is, for example, 0.05 MPa to 1 MPa, but it is better to be as close to the atmospheric pressure as possible. The reason is that pressure is constantly applied, and it is desirable that the pressure be low when considering leaks. Above P ₁ , P ₂ , P
The relationship of ₃ is P ₃ > P ₂ > P ₁ (however, in the case of vacuum pressure transportation, P ₃ becomes a negative pressure).

(2) Direction changing portions 5a, 5b, 5c of FIG.
When perforation due to collision wear occurs in the inner tube 21 of the wear detecting air feeding tube 20 installed in the air feeding during air feeding, the sealed space 24 communicates with the inner tube 21, that is, the powder air feeding pipe 5, and the sealed space 24
The pressure P ₂ of the inner rises P ₂ = P _3, and the the air transfer pressure P _3. In the computer, P ₂ and P ₃ are compared and P ₂
= P ₃ , it is determined that the hole is open. Even if the inner tube 21 is perforated, the outer tube 22 prevents the powder, oxygen gas, and the like from leaking, so that pneumatic transportation can be continued.

(3) For some reason (heat expansion / contraction, natural force such as earthquake) when air is not being sent, a crack hole is formed in the wear-reducing pipe portion of the inner pipe 21 of the wear-detecting air-feeding pipe 20. When it occurs, the sealed space 24 communicates with the inside of the inner pipe 21, that is, the inside of the powder feeding pipe 5, and the pressure P ₂ inside the sealed space 24 is P ₂ = P
_It becomes ₁ and falls to the pressure P ₁ at the time of stopping air feeding. The computer compares P ₂ and P ₁ , and if P ₂ = P ₁ , determines that the hole is perforated.

[B] Prevention of Secondary Accident / Disaster (1) As described above, by constantly monitoring the pressure P ₂ in the sealed space 24 of the wear detecting pneumatic tube 20, during pneumatic or non- pneumatic transportation. Regardless of this, it is possible to detect the perforation of the powder pneumatic pipe 5 at the same time as it is generated, and an alarm is output to the operator by the perforation detection.

(2) Simultaneously with this alarm, the base end shutoff valve 10 on the supply side of the powder pneumatic equipment and the shutoff valve 14 of the carrier gas supply pipe 8 for O ₂ shown in FIG. The supply of O ₂ is stopped. The tip shutoff valve 11 is also closed depending on the detection site.

(3) Next, the shut-off valve 17 of the bypass pipe 18 for the inert gas such as N ₂ is opened to supply N ₂ or the like into the powder feeding pipe 5, and then the powder feeding pipe 5 Purge the remaining powder in. If the tip shutoff valve 11 is closed,
It goes without saying that the opening operation is performed.

As described above, a series of operations from the shutoff valve opening / closing operation after the detection of collision wear perforation at a specific wear site to the execution of purging are automatically performed to leak powder or O ₂ Surely prevent secondary accidents and disasters caused by.

[0057]

EXAMPLE In order to test the function of the wear detecting pneumatic feeding pipe 20 shown in FIG. 2 using the powder pneumatic feeding equipment shown in FIG. 1, powder transportation was repeatedly carried out. The step I was intended for the wear detection system to function normally, and the step II was for the purpose of grasping the wear state of the pneumatic piping system.

When the refining powder is supplied from the upper blowing lance to the hot metal and molten steel, the internal pressure P ₃ of the pneumatic piping is 0.3 to
It became 0.6 MPa. This is a value that changes depending on the amount of powder delivered to the air. When the amount of air delivered (changing the solid-gas ratio) is increased, the pressure loss increases and the pressure becomes high. Further, the internal pressure P ₁ of the pneumatic piping when the pneumatic transportation is stopped is 0.0
It was MPa. In addition, assuming that the specific wear site causes wear thinning holes during this large-scale test and P ₂ and P ₃ have the same pressure, P ₂ is set to 0.098 MPa,
I ran the system. P ₂ continued to be maintained at 0.098 MPa.

Unfortunately, no perforation did not occur during such a large amount test, so the double pipe portion of the specific wear site was forcibly opened from the outside during non-pneumatic delivery, and P ₂ = P ₁ = large When a test was conducted to change the pressure to atmospheric pressure, an "alarm" was issued and the emergency shutoff valve was "closed", confirming that the functions of the original plan could be achieved.

The wear detecting tube and the constant pressure monitoring system as described above are as follows.
Of course, it can also be applied to other pneumatic systems. For example, as shown in FIG. 1, N ₂ is used as a carrier gas for powder feeding from the powder receiving unit 1 (jet back vehicle) to the storage tank 2. It can also be used for 4.

Further, although the powder pneumatic feeding equipment in the converter has been exemplified above, the present invention can be used not only for powder transportation but also widely for detecting perforation of wear and corrosion of general pneumatic feeding pipes and liquid feeding pipes. . Specific examples thereof include a gas / liquid transportation pipe for transporting a specific weak point portion of the pipe such as a bent portion of a pipe or a portion where drainage is accumulated, or a case where a flammable or harmful toxic substance is transported.

Another object of the present invention is to attach a "wear detection tube" to a specific wear range, constantly monitor it, and detect an abnormality, and at the same time, to automatically take an emergency response. Yes, there is a series of equipment operations for this purpose and its operation method / safety management system. As a matter of course, when a person gives a warning when "abnormality detection" is made and a judgment is made by a human, a series of methods including the field of "software" for operating these devices such as the order of shutoff valves "closed" are also included. It is a thing.

[0063]

Since the present invention is constructed as described above, it has the following effects.

(1) The pressure detector constantly monitors changes in internal pressure in a specific worn portion of the transportation pipe, or an abnormality detection device that is a double pipe type transportation pipe is used to detect the direction of transportation in the specific worn portion of the transportation pipe. By arranging in the conversion part, etc., and constantly monitoring the internal pressure P ₂ between the inner pipe and the outer pipe of the double pipe, wear pipes such as air feeding pipes and liquid feeding pipes are missing holes such as holes. Can be detected early in a reliable manner by a relatively simple and inexpensive device regardless of whether it is being transported or not.

(2) When the double pipe type transportation pipe abnormality detecting device is used, since it is a double pipe consisting of an inner pipe and an outer pipe, there is an outer pipe even if a hole is formed in the inner pipe. The powder, fluid, etc. do not leak, and the transportation can be continued.

(3) As described above, the perforation of the transportation pipe is quickly caught, the operator of the facility is alerted, the operation of the transportation system equipment is automatically stopped, and the inside of the transportation pipe is purged, thereby transporting the transportation object. It is possible to reliably prevent secondary accidents and disasters due to leakage of transportation fluid. As a result, in the method of supplying the refining powder to the hot metal / molten steel by pneumatic feeding, a refining method that requires oxygen as a carrier gas has been realized. It can also be used in powder transportation and gas / liquid transportation in which perforation due to wear and corrosion of piping in general pneumatic / liquid transportation equipment poses a problem.

[Brief description of drawings]

FIG. 1 is a system diagram showing an example of a powder pneumatic equipment to which the present invention is applied.

FIG. 2 is a side view showing a specific example of an abnormality detection device used in the present invention.

FIG. 3 is a system diagram showing an example of a powder pneumatic feeding facility that has been conventionally used.

FIG. 4 is a bend pipe in a conventional powder pneumatic pipe,
(a) is a side view in which a part thereof is cut away, and (b) is a sectional view.

[Explanation of symbols]

1 ... Powder receiving part 2 ... Storage tank 3 ... Dust collector 4 ... Powder pneumatic piping 5 ... Powder pneumatic piping 5a, 5b, 5c ... Direction changing part 6 ... Powder blowing lance 7 ... Carrier gas supply pipe for N ₂ etc. 8 Carrier gas supply pipe for O ₂ 10 Base end shutoff valve 11 Tip shutoff valve 12 Shutoff valve 13 Pressure adjusting valve 14 Shutoff valve 15 ... Flow rate adjusting valve 16 ... Flow rate control orifice 17 ... Shutoff valve 18 ... Bypass pipe 20 ... Abnormality detection device (wear detection air feeding pipe) 21 ... Inner pipe 22 ... Outer pipe 23 ... Connection flange 24 ... ... Sealed space 25 ... Connection flange 30 ... Fluid supply pipe 31 ... Pressure detector 32 ... Open / close valve 33 ... One-touch joint 34 ... Transmitter 35 ... Open / close valve 36 ... Pressure detection transmitter 40 ... Curved pipe part 41 ... Straight pipe part

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Toshinori Ando             Sumitomo Metal Industries, No. 3, Hikari, Oshima, Kashima City, Ibaraki Prefecture             Kashima Steel Works Co., Ltd. (72) Inventor Haruo Watanabe             Denka, 6-5 Goi Minami Coast, Ichihara City, Chiba Prefecture             Engineering Co., Ltd. Chiba Office F-term (reference) 3F047 AB00 AB02 BA02 BA04 CA02                       CC28                 4K070 AB02 AB05 AB06 AC01 AC02                       CE04

Claims (11)

[Claims] 1. A method for detecting an abnormality in a transportation pipe for transporting an object, comprising detecting a defect in the transportation pipe at an initial stage by constantly monitoring a state of wear in the transportation pipe. Anomaly detection method. 2. A method for detecting an abnormality in a transportation pipe for transporting an object, wherein an arbitrary portion of the transportation pipe is a double pipe in which an inner pipe and an outer pipe are hermetically sealed, and the inner pipe and the outer pipe are connected to each other. A method for detecting an abnormality in a transportation pipe, which detects a defect in the transportation pipe at an initial stage by continuously measuring an internal pressure. 3. The abnormality detecting method according to claim 2, wherein gas or liquid is filled between the inner pipe and the outer pipe of the double pipe so that the inside of the double pipe is between the inner pipe and the outer pipe. A method for detecting abnormality in a transportation pipe, comprising controlling the pressure to be constant, continuously measuring the internal pressure, and determining that the transportation pipe is defective when the measured value fluctuates. 4. The abnormality detection method according to claim 2, wherein the pressure in the transportation pipe when the object is not transported is P _1, and the internal pressure between the inner pipe and the outer pipe of the double pipe is set. To P ₂
And P ₂ is controlled so that P ₂ > P _1, and this P ₂
A method for detecting an abnormality in a transportation pipe, characterized in that it is determined that the transportation pipe has been lost when is lower than a control value. 5. The method according to claim 2, 3 or 4, wherein the pressure in the transportation pipe during transportation of the object is P ₃
And the internal pressure between the inner and outer pipes of the double pipe is P ₂ ,
A method for detecting an abnormality in a transport pipe, which comprises controlling P ₂ so that P ₃ > P ₂ and determining that the transport pipe is defective when P ₂ becomes higher than a control value. 6. The method for detecting an abnormality according to claim 1, 2, 3, 4, or 5, wherein the portion for detecting a defect in the transportation pipe is a direction changing portion for changing the transportation direction of the transportation pipe. A method for detecting abnormalities in transportation piping. 7. When a defect of the transportation pipe is detected by the abnormality detecting method according to claim 1, 2, 3, 4, 5 or 6, an alarm is issued and the operation of the transportation system equipment is automatically stopped,
A transportation condition safety monitoring method characterized by purging the inside of a transportation pipe. 8. An abnormality detection device for a transportation pipe for transporting an object, comprising an inner pipe and an outer pipe, the inner pipe being connected to the transportation pipe so as to be able to communicate with each other, and the inner pipe and the outer pipe being in a sealed state. And a pressure detector for detecting the internal pressure between the inner pipe and the outer pipe. 9. The abnormality detecting device according to claim 8, further comprising a supply pipe for supplying gas or liquid between the inner pipe and the outer pipe. 10. The abnormality detecting device according to claim 8 or 9, wherein the abnormality detecting pipe is composed of a curved pipe portion and a straight pipe portion connected to a downstream side of the curved pipe portion. An abnormality detection device for transportation piping. 11. The transportation according to claim 10, wherein when the radius of curvature of the curved pipe portion is R, the length of the straight pipe portion is 0.5R to 1.0R. Piping abnormality detection device.