JPH0882518A - Slag thickness measuring apparatus - Google Patents
Slag thickness measuring apparatusInfo
- Publication number
- JPH0882518A JPH0882518A JP6218625A JP21862594A JPH0882518A JP H0882518 A JPH0882518 A JP H0882518A JP 6218625 A JP6218625 A JP 6218625A JP 21862594 A JP21862594 A JP 21862594A JP H0882518 A JPH0882518 A JP H0882518A
- Authority
- JP
- Japan
- Prior art keywords
- slag
- furnace
- echo
- thickness
- probe
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Withdrawn
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- Investigating Or Analyzing Materials By The Use Of Ultrasonic Waves (AREA)
- Length Measuring Devices Characterised By Use Of Acoustic Means (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は石炭燃焼炉、ガス化炉、
等の火炉内壁に付着するスラグ厚み計測装置に関する。The present invention relates to a coal combustion furnace, a gasification furnace,
The present invention relates to a slag thickness measuring device that adheres to the inner wall of a furnace.
【０００２】[0002]
【従来の技術】石炭燃焼炉、石炭ガス化炉等の火炉内壁
に付着するスラグ（石炭に含まれる灰分が高温１５００
℃程度で溶け液状になったものであり、１２００℃以下
では凝固して固体となる）の厚みはそれが大きくなると
炉の運転に支障があるため常時モニタする必要がある。
炉内は高温のため、スラグ厚みを計測するセンサ、等の
物体を挿入できないため、炉の外側より計測する必要が
あるが、従来は図４に示すような超音波を使った計測方
法を使用していた。2. Description of the Related Art Slag adhering to the inner wall of a furnace such as a coal combustion furnace or a coal gasification furnace (ash contained in coal has a high temperature of 1500
(It melts into a liquid state at about 0 ° C and solidifies at 1200 ° C or less to become a solid). If the thickness increases, it hinders the operation of the furnace and must be constantly monitored.
Since the inside of the furnace is hot, it is necessary to measure from the outside of the furnace because objects such as sensors for measuring slag thickness cannot be inserted. Conventionally, the ultrasonic measurement method shown in Fig. 4 was used. Was.
【０００３】図４において、炉壁１の炉内１０側にスラ
グ２が付着している。この付着厚みを計測する場合に、
超音波探触子３より超音波をスラグ２内に入射するが、
スラグ２は高温のため、直接探触子３を接触させること
ができないこと、及び炉壁１は耐火材で構成され、通常
多孔質なため超音波は透過しないことにより、超音波が
透過しやすい遅延材２４を炉壁１に挿入し、これを介し
てスラグ２内に超音波を入射している。５は超音波送受
信器であり、探触子３を作動させて超音波を送信すると
ともに、探触子３で受信された受信信号を増幅し、オシ
ロスコープ６に出力する。そしてオシロスコープ６にて
送受信信号をモニタする。In FIG. 4, a slag 2 is attached to the inside 10 of the furnace wall 1. When measuring this adhesion thickness,
An ultrasonic wave is injected into the slug 2 from the ultrasonic probe 3,
Since the slag 2 has a high temperature, the probe 3 cannot be directly contacted with it, and since the furnace wall 1 is made of a refractory material and is usually porous and does not transmit ultrasonic waves, ultrasonic waves easily pass through. The delay material 24 is inserted into the furnace wall 1, and the ultrasonic wave is injected into the slag 2 via the delay material 24. An ultrasonic wave transmitter / receiver 5 operates the probe 3 to transmit ultrasonic waves, amplifies the reception signal received by the probe 3, and outputs the amplified signal to the oscilloscope 6. Then, the transmission / reception signal is monitored by the oscilloscope 6.
【０００４】ここで、送受信の状況を説明すると、探触
子３より発せられた超音波の送信波７は遅延材２４の中
を伝播し、その炉内側端面８にて一部反射されるが残り
はスラグ２の中に入射される。スラグ２内に入射された
超音波はスラグ２の炉内側表面９にて全反射され、７′
で示すように送信と同じ経路を通って探触子３にて受信
される。Here, the transmission and reception conditions will be described. The ultrasonic transmission wave 7 emitted from the probe 3 propagates in the delay material 24 and is partially reflected by the furnace inner end surface 8. The rest is injected into the slag 2. The ultrasonic waves incident on the inside of the slag 2 are totally reflected by the furnace inner surface 9 of the slag 2, and 7 '
As shown by, the probe 3 receives the signal through the same route as the transmission.
【０００５】その時のオシロスコープ６でのモニタ例を
図５に示す。図５において、横軸は送信時を基準とした
時間であり、縦軸は受信信号の強度である。送信波７は
時間０の所にあり、それよりｔ1 時間経過した所に遅延
材端面８でのエコー１１が現れ、更にｔ3 経過の所にス
ラグの炉内側表面９でのスラグ面エコー１２が現れる。FIG. 5 shows an example of monitoring by the oscilloscope 6 at that time. In FIG. 5, the horizontal axis is the time with reference to the time of transmission, and the vertical axis is the intensity of the received signal. The transmitted wave 7 is at time 0, an echo 11 appears at the end face 8 of the delay material at a time t 1 hours after that, and a slag surface echo 12 at the furnace inner surface 9 at a time t 3 further. Appears.
【０００６】エコー１１とエコー１２との時間差ｔ3 が
スラグ２内での超音波の往復伝播時間である。スラグ２
の厚みＬとこのｔ3 の大きさとは次式の関係にあるた
め、スラグの厚みＬを求めることができる。The time difference t 3 between the echo 11 and the echo 12 is the round-trip propagation time of ultrasonic waves in the slag 2. Slag 2
Since the thickness L of the slag and the size of this t 3 have the following relationship, the thickness L of the slag can be obtained.
【０００７】Ｌ＝（ｔ3 ／２）×Ｃ； ここで、Ｌ：ス
ラグ厚み（ｍ）、Ｃ：スラグ内での超音波音速（ｍ／se
c ）である。[0007] L = (t 3/2) × C; wherein, L: slag thickness (m), C: ultrasonic speed of sound in the slag (m / se
c).
【０００８】[0008]
【発明が解決しようとする課題】従来例では遅延材２４
を用いることにより高温スラグ２の厚みを計測できた
が、遅延材の長さが大きくなると遅れエコーと呼ばれる
別のエコーが発生し、スラグ面からのエコーの判別を困
難にする問題点があった。In the conventional example, the delay member 24 is used.
Although the thickness of the high-temperature slag 2 can be measured by using, the problem is that if the length of the delay material increases, another echo called a delayed echo is generated, which makes it difficult to distinguish the echo from the slag surface. .
【０００９】遅れエコーとは、図６（ｂ）に示すよう
に、遅延材の側面に当った縦波がＡ点で横波に変わり
（モード変換という）、さらにＢ点で再び縦波に変って
探触子に戻るためである。また、横波での複数回の側面
反射もあるなど各種の経路があるため、図６（ａ）に示
すようにＢ′、Ｂ′′、Ｂ′′′と多数のエコー１３を
生じることである。遅れエコー１３が底面エコーＢより
遅れる時間Δｔは次式により求められる。As shown in FIG. 6 (b), the delayed echo means that a longitudinal wave hitting the side surface of the delay material changes to a transverse wave at point A (called mode conversion), and further changes to a longitudinal wave at point B. This is to return to the probe. Further, since there are various paths such as multiple side reflections due to transverse waves, B ', B'',B''' and many echoes 13 are generated as shown in FIG. 6 (a). . The time Δt at which the delayed echo 13 lags the bottom echo B is calculated by the following equation.
【００１０】[0010]
【数１】 [Equation 1]
【００１１】ここで、ＣL ：縦波の音速、ＣS ：横波の
音速である。これにより、一応判別はできるが、図７に
示すように遅れエコー１３が計測対象とするスラグ面か
らのエコー１２と重なるため、それが判別できにくいと
ゆう問題点があった。Here, C L is a longitudinal wave sound velocity, and C S is a transverse wave sound velocity. As a result, although it is possible to make a distinction, the delayed echo 13 overlaps with the echo 12 from the slag surface to be measured as shown in FIG. 7, which makes it difficult to make a distinction.
【００１２】[0012]
【課題を解決するための手段】本発明はこのような課題
を解決するために、超音波が伝播する遅延材の形状を炉
内に向って一部又は全長が超音波の拡り角に合わせてテ
ーパ状に広がった形状として遅れエコーが発生しない形
状とした計測装置とする。In order to solve such a problem, the present invention adjusts the shape of a delay material in which ultrasonic waves propagate to the inside of the furnace so that a part or the whole length thereof is adjusted to the spread angle of ultrasonic waves. The measuring device has a taper-like shape that does not cause delayed echo.
【００１３】即ち、本発明は、燃焼炉の炉壁を貫通して
挿入した遅延材と、その一端に設けた探触子から前記遅
延材を介して超音波を受発信し、同超音波の伝播時間に
より炉内の前記炉壁に付着したスラグ厚みを計測するス
ラグ厚み計測装置において、前記遅延材は前記探触子と
スラグの間で前記炉内に向って広がったテーパ状である
ことを特徴とするスラグ厚み計測装置を提供する。That is, according to the present invention, a delay member inserted through the furnace wall of a combustion furnace and an ultrasonic wave are transmitted and received from a probe provided at one end of the delay member through the delay member, In the slag thickness measuring device for measuring the slag thickness attached to the furnace wall in the furnace by the propagation time, the delay material is a tapered shape that spreads toward the inside of the furnace between the probe and the slag. A characteristic slag thickness measuring device is provided.
【００１４】[0014]
【作用】本発明はこのような手段により、探触子から発
射した送信波は、遅延材が炉内に向って広がったテーパ
形状であり、このテーパ形状を超音波の拡がり角に合わ
せておくと超音波は遅延材の側面に当って反射すること
なくそのまま伝播する。伝播した超音波は炉内側端面で
一部が反射し、残りがスラグ内に入り、スラグ表面で全
反射し、再び遅延材を伝播して探触子に戻ってくる。こ
の時の炉内側端面で反射した際に生ずる遅延材端面エコ
ーとスラグ表面で反射した際に生ずるスラグ面エコーと
の時間差よりスラグの厚さが求まるが、遅延材の側面で
の反射で生ずる遅れエコーが発生しないので前述のエコ
ーと遅れエコーとの重なりもなく、スラグの厚みを正確
に計測することができる。According to the present invention, the transmission wave emitted from the probe by such means has a taper shape in which the delay material spreads toward the inside of the furnace, and this taper shape is adjusted to the spread angle of ultrasonic waves. And the ultrasonic wave propagates as it is without hitting the side surface of the delay member and being reflected. A part of the propagated ultrasonic wave is reflected on the end surface inside the furnace, the rest enters the slag, is totally reflected on the surface of the slag, propagates again through the delay material, and returns to the probe. At this time, the thickness of the slag is obtained from the time difference between the echo of the end surface of the delay material that occurs when reflected on the end face inside the furnace and the echo of the slag surface that occurs when reflected on the slag surface. Since the echo does not occur, the aforementioned echo and the delayed echo do not overlap with each other, and the thickness of the slag can be accurately measured.
【００１５】[0015]
【実施例】以下、本発明の実施例を図面に基づいて具体
的に説明する。図１は本発明の第１の実施例に係るスラ
グ厚み計測装置の構成図、図２は図１における遅延材の
外形寸法を示す図である。図１において、符号１乃至３
及び５乃至１０は図４の従来例と同じであるので詳しい
説明は省略し、そのまま引用して説明する。本発明の特
徴となる部分は遅延材４の部分にあり、遅延材４は図２
に示すようにテーパ状としたものである。Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a configuration diagram of a slag thickness measuring device according to a first embodiment of the present invention, and FIG. 2 is a diagram showing external dimensions of the delay material in FIG. In FIG. 1, reference numerals 1 to 3
Since 5 and 10 are the same as those in the conventional example of FIG. The characteristic part of the present invention resides in the part of the delay member 4, which is shown in FIG.
As shown in FIG.
【００１６】遅延材４としては、図１、２に示すように
炉内側の直径を少くとも探触子３から発する送信波７の
拡がり角に合せて炉外側より大きくし、テーパ状とした
ものを用いる。遅延材４の形状・寸法を図２に示す。超
音波の拡がり角θは通常次式で表される。As the delay member 4, as shown in FIGS. 1 and 2, the diameter of the inside of the furnace is made larger than that of the outside of the furnace in accordance with the divergence angle of the transmitted wave 7 emitted from the probe 3, and is tapered. To use. The shape and dimensions of the delay member 4 are shown in FIG. The spread angle θ of ultrasonic waves is usually expressed by the following equation.
【００１７】θ≒１４０×λ／Ｄ（度）；ここで、λ：
超音波波長、Ｄ：探触子直径である。Θ≈140 × λ / D (degrees); where λ:
Ultrasonic wavelength, D: probe diameter.
【００１８】遅延材材質をセラミック、超音波周波数を
２ＭHzとすると、λは５mm程度である。Ｄを２０mmとす
るとθは３５°である。When the delay material is ceramic and the ultrasonic frequency is 2 MHz, λ is about 5 mm. If D is 20 mm, θ is 35 °.
【００１９】図２に示すように、遅延材の超音波入射側
の直径をｄ、長さをＬ1 とすると、 ｄ1 ＝２×Ｌ1 ×tan （θ／２）；となる。As shown in FIG. 2, when the diameter of the delay member on the ultrasonic wave incident side is d and the length is L 1 , d 1 = 2 × L 1 × tan (θ / 2);
【００２０】テーパの長さＬ2 は、Ｌ2 ＝１／２×（ｄ
1 −ｄ）／tan （θ／２）；となる。The length L 2 of the taper is L 2 = 1/2 × (d
1- d) / tan (θ / 2);
【００２１】Ｌ1 を１００mm、ｄを２０mmとすると、ｄ
1 ＝６３mm、Ｌ2 ＝６８となる。If L 1 is 100 mm and d is 20 mm, d
1 = 63 mm and L 2 = 68.
【００２２】このようなテーパ状の形状・寸法の遅延材
４を用いると、図１において探触子３より発射された超
音波の送信波７は途中で遅延材４の側面に当ることなく
遅延材４の内部を伝播し、その端面８にて一部反射され
るが、残りはスラグ２の中に入射される。スラグ２内に
入射された超音波はスラグの表面９にて全反射され、送
信と同じ経路を通って探触子３にて受信される。When the delay member 4 having such a tapered shape and size is used, the ultrasonic transmission wave 7 emitted from the probe 3 in FIG. 1 is delayed without hitting the side surface of the delay member 4 on the way. The light propagates inside the material 4 and is partially reflected by the end face 8, but the rest is incident on the slag 2. The ultrasonic wave that has entered the slag 2 is totally reflected by the surface 9 of the slug 2 and is received by the probe 3 through the same path as the transmission.
【００２３】この場合，遅延材４は超音波の拡がり角に
合せ、テーパ状となっているため側面に当っての反射波
がなくなり、遅れエコーが発生しないので、図５のよう
にスラグ面からのエコー１２を明瞭に判別できるためス
ラグ厚みを精度良く計測できる。In this case, since the delay material 4 is tapered in accordance with the spread angle of ultrasonic waves, the reflected wave that strikes the side surface disappears and a delayed echo does not occur. Therefore, as shown in FIG. Since the echo 12 can be clearly discriminated, the slag thickness can be accurately measured.
【００２４】図３は遅延材の形状を変えた第２実施例
で、遅延材１４として全長をラッパ状にテーパ形状とし
たものである。この場合は寸法ｄ′の一端より探触子か
ら超音波を発し、テーパの形状を少くとも超音波の拡が
り角度に合わせるようにすれば、前述の第１実施例と同
様の作用、効果を奏するものである。FIG. 3 shows a second embodiment in which the shape of the delay member is changed, and the delay member 14 has a trumpet shape in its entire length. In this case, if the ultrasonic wave is emitted from the probe from one end of the dimension d'and the taper shape is adjusted to at least the spread angle of the ultrasonic wave, the same operation and effect as the above-described first embodiment can be obtained. It is a thing.
【００２５】なお、本発明の計測装置は、スラグの厚み
測定の実施例で説明したが、これに限定されず、溶鉄、
溶鋼の厚み、回収ボイラ炉内のチャー厚み、等にも適用
できるものである。Although the measuring device of the present invention has been described in the embodiment for measuring the thickness of slag, the measuring device is not limited to this, and molten iron,
It can also be applied to the thickness of molten steel, the thickness of char in the recovery boiler furnace, and the like.
【００２６】[0026]
【発明の効果】以上、具体的に説明したように、本発明
においては、超音波が伝播する遅延材の形状を炉内に向
って広がったテーパ状として遅れエコーが発生しないよ
うな構成としたので、遅れエコーの発生によるエコーの
重なりがなく、炉内のスラグ厚みを精度良く計測できる
ため、炉の運転状態を的確に把握でき、運転効率の向
上、安全性の向上に寄与するため産業上有益である。As described above in detail, in the present invention, the configuration of the delay material in which ultrasonic waves propagate is tapered so as to spread toward the inside of the furnace so that delayed echo does not occur. Since there is no overlap of echoes due to the generation of delayed echoes, and the slag thickness in the furnace can be measured accurately, it is possible to accurately grasp the operating state of the furnace and contribute to the improvement of operating efficiency and safety, which is an industrial advantage. Be beneficial.
【図１】本発明の第１実施例に係るスラグ厚み計測装置
の構成図である。FIG. 1 is a configuration diagram of a slag thickness measuring device according to a first embodiment of the present invention.
【図２】本発明の第１実施例における遅延材の寸法を示
す図である。FIG. 2 is a diagram showing dimensions of the retarder in the first embodiment of the present invention.
【図３】本発明の第２実施例における遅延材の外形を示
す図である。FIG. 3 is a diagram showing an outer shape of a delay member according to a second embodiment of the present invention.
【図４】従来のスラグ厚み計測装置の構成図である。FIG. 4 is a configuration diagram of a conventional slag thickness measuring device.
【図５】スラグ厚み計測装置の一般的な波形図で、遅れ
エコーがない時のエコーの状態を示す。FIG. 5 is a general waveform diagram of a slag thickness measuring device, showing an echo state when there is no delayed echo.
【図６】従来の計測装置で発生する遅れエコーの説明図
で、（ａ）は探傷波形図、（ｂ）は超音波の経路図をそ
れぞれ示す。6A and 6B are explanatory diagrams of a delayed echo generated in a conventional measuring device, FIG. 6A is a flaw detection waveform diagram, and FIG. 6B is an ultrasonic path diagram.
【図７】従来の計測装置での遅れエコーがある時の波形
図である。FIG. 7 is a waveform diagram when there is a delayed echo in the conventional measuring device.
１ 炉壁 ２ スラグ ３ 探触子 ４ 遅延材 ５ 超音波送受信器 ６ オシロスコープ ７ 送信波 ８ 炉内側端面 ９ スラグ炉内側表面 １０ 炉内 １４ 遅延材 1 Furnace Wall 2 Slag 3 Probe 4 Delay Material 5 Ultrasonic Transceiver 6 Oscilloscope 7 Transmitted Wave 8 Inner End Face 9 Slag Inner Surface 10 Inside Furnace 14 Delay Material
Claims (1)
と、その一端に設けた探触子から前記遅延材を介して超
音波を受発信し、同超音波の伝播時間により炉内の前記
炉壁に付着したスラグ厚みを計測するスラグ厚み計測装
置において、前記遅延材は前記探触子とスラグの間で前
記炉内に向って広がったテーパ状であることを特徴とす
るスラグ厚み計測装置。1. A delay material inserted through a furnace wall of a combustion furnace, and an ultrasonic wave is transmitted and received from a probe provided at one end of the delay material through the delay material, and a furnace is generated according to a propagation time of the ultrasonic wave. In the slag thickness measuring device for measuring the slag thickness attached to the furnace wall inside, the delay member is a slag that is spread between the probe and the slag toward the inside of the furnace. Thickness measuring device.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP6218625A JPH0882518A (en) | 1994-09-13 | 1994-09-13 | Slag thickness measuring apparatus |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP6218625A JPH0882518A (en) | 1994-09-13 | 1994-09-13 | Slag thickness measuring apparatus |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0882518A true JPH0882518A (en) | 1996-03-26 |
Family
ID=16722892
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP6218625A Withdrawn JPH0882518A (en) | 1994-09-13 | 1994-09-13 | Slag thickness measuring apparatus |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0882518A (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20020052748A (en) * | 2000-12-26 | 2002-07-04 | 이구택 | Thickness measurement of ceramic paste at a blast furnace |
| TWI456162B (en) * | 2012-01-20 | 2014-10-11 | China Steel Corp | Blast furnace stave thickness ultrasonic measuring method and device thereof |
| JP2018179790A (en) * | 2017-04-14 | 2018-11-15 | 日立造船株式会社 | Space determination method, space determination system and elastic wave detection method |
| CN113654501A (en) * | 2021-04-28 | 2021-11-16 | 温州广业建设有限公司 | Floor height detection device for building construction quality inspection |
-
1994
- 1994-09-13 JP JP6218625A patent/JPH0882518A/en not_active Withdrawn
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR20020052748A (en) * | 2000-12-26 | 2002-07-04 | 이구택 | Thickness measurement of ceramic paste at a blast furnace |
| TWI456162B (en) * | 2012-01-20 | 2014-10-11 | China Steel Corp | Blast furnace stave thickness ultrasonic measuring method and device thereof |
| JP2018179790A (en) * | 2017-04-14 | 2018-11-15 | 日立造船株式会社 | Space determination method, space determination system and elastic wave detection method |
| CN113654501A (en) * | 2021-04-28 | 2021-11-16 | 温州广业建设有限公司 | Floor height detection device for building construction quality inspection |
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Legal Events
| Date | Code | Title | Description |
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| A300 | Withdrawal of application because of no request for examination |
Free format text: JAPANESE INTERMEDIATE CODE: A300 Effective date: 20011120 |