JPH0550234A - Device for underwater cutting of steel material - Google Patents
Device for underwater cutting of steel materialInfo
- Publication number
- JPH0550234A JPH0550234A JP21503791A JP21503791A JPH0550234A JP H0550234 A JPH0550234 A JP H0550234A JP 21503791 A JP21503791 A JP 21503791A JP 21503791 A JP21503791 A JP 21503791A JP H0550234 A JPH0550234 A JP H0550234A
- Authority
- JP
- Japan
- Prior art keywords
- cutting
- cutting device
- arc
- frequency generator
- water
- 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.)
- Granted
Links
Landscapes
- Placing Or Removing Of Piles Or Sheet Piles, Or Accessories Thereof (AREA)
- Arc Welding In General (AREA)
Abstract
Description
【０００１】[0001]
【産業上の利用分野】本発明は、水中に打設された鋼管
杭、鋼管矢板等の鋼材を切断する技術に関する。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for cutting steel materials such as steel pipe piles and steel pipe sheet piles that are cast in water.
【０００２】[0002]
【従来の技術】本発明者らは、岸壁水中構造物、橋脚立
設工事、水中仮締切工事、岸壁・埋立工事等で水底に打
設された鋼管杭、鋼管矢板等の鋼材の竣工後の不要部分
を除去するための水中切断技術について鋭意研究の結
果、プラズマアーク切断によるきわめて高能率の切断技
術を完成し、特開昭64-90317号公報、特開平1-170579号
公報、特開平2-132225号公報等により公開されている。2. Description of the Related Art The inventors of the present invention have proposed that after the completion of construction of steel materials such as steel pipe piles and steel pipe sheet piles that have been cast on the bottom of the water in quay underwater structures, pier erection work, underwater temporary shutoff work, quay / landfill work, etc. As a result of diligent research on underwater cutting technology for removing unnecessary portions, a very high efficiency cutting technology by plasma arc cutting was completed, and JP-A 64-90317, JP-A 1-170579, and JP-A 2 -132225 publication.
【０００３】図５、図６に示すのは特開平2-132225号公
報に記載の切断装置の一実施例で、図５は全体図であ
る。切断すべき鋼管１の上端に、任意の高さ調整手段２
を介して支持台座３を設置し、この支持台座３から吊り
索４、４を介して切断装置本体５を鋼管１内に吊り下げ
る。2aは装置全体を吊りこむクレーンロープで、支持台
座３の設置後はゆるめても支障ない。図６は本体部分の
詳細図で、切断装置本体５の下板5aには、切断装置本体
５を鋼管１の内面に保持固定する保持手段８が設けられ
ていて、液体圧シリンダ等により前進・後退し、吊り下
げて高さ調整が完了するとこの保持手段が前進して切断
装置本体５を鋼管１に対して固定する。なお、この保持
手段８は、のちに図１に示すように、切断装置本体５の
上下に２段に設置してもよい。FIGS. 5 and 6 show an embodiment of the cutting device disclosed in Japanese Patent Laid-Open No. 2-132225, and FIG. 5 is an overall view. An arbitrary height adjusting means 2 is provided on the upper end of the steel pipe 1 to be cut.
The support pedestal 3 is installed via the pedestal, and the cutting device main body 5 is hung from the support pedestal 3 via the suspension lines 4 and 4 in the steel pipe 1. Reference numeral 2a is a crane rope for suspending the entire apparatus, which can be loosened after the support base 3 is installed. FIG. 6 is a detailed view of the main body portion. The lower plate 5a of the cutting device main body 5 is provided with a holding means 8 for holding and fixing the cutting device main body 5 to the inner surface of the steel pipe 1, and the moving means is advanced by a liquid pressure cylinder or the like. When it is retracted, suspended and height adjustment is completed, this holding means moves forward and fixes the cutting device body 5 to the steel pipe 1. The holding means 8 may be installed in two stages above and below the cutting device body 5, as shown in FIG.
【０００４】一方、切断装置本体５の下板5a中央部には
モータ10、減速機11が取り付けられ、減速機11からの回
転軸11a は下方に突出し、下端に台座12が水平に取り付
けられている。この台座12の下面には流体圧シリンダ13
がおなじく水平に設置され、この流体圧シリンダ13のピ
ストンロッド13a 先端部下面にはプラズマトーチ14が水
平に設置され、流体圧シリンダ13の前進動作によりプラ
ズマトーチ14の先端が鋼管１の内面に接近し、前記回転
軸11a の回転により鋼管１の内面を一周してこれを切断
するようになっている。On the other hand, a motor 10 and a speed reducer 11 are attached to the central portion of the lower plate 5a of the cutting device body 5, a rotary shaft 11a from the speed reducer 11 projects downward, and a pedestal 12 is horizontally attached to the lower end. There is. The bottom surface of this pedestal 12 is a fluid pressure cylinder 13
Is installed horizontally, and the plasma torch 14 is installed horizontally on the lower surface of the tip of the piston rod 13a of the fluid pressure cylinder 13. The forward movement of the fluid pressure cylinder 13 causes the tip of the plasma torch 14 to approach the inner surface of the steel pipe 1. Then, the inner surface of the steel pipe 1 is circulated by the rotation of the rotating shaft 11a and cut.
【０００５】プラズマトーチ14先端と切断対象物である
鋼管１の内面とはスタンドオフと称する一定の距離を保
持することが望ましいので、前記ピストンロッド13a 先
端には鋼管１の内面に接触する位置決めローラ（図示し
ない) が設けられている。なお、プラズマアーク用雰囲
気ガス源、プラズマアーク用電源、モータ用電源、液体
圧シリンダ用液体圧発生装置等はいずれも切断作業現場
近傍の地上にこれらの制御装置とともに設置され、これ
らと切断装置とはケーブルやホース（以下これらを総称
してケーブル類という）で連絡されている。これらケー
ブル類、特に電源ケーブルは水中における絶縁性を確保
するため防水構造がとられていることは、いうまでもな
い。Since it is desirable to maintain a certain distance called a standoff between the tip of the plasma torch 14 and the inner surface of the steel pipe 1 to be cut, the tip of the piston rod 13a has a positioning roller which contacts the inner surface of the steel pipe 1. (Not shown) is provided. Atmosphere gas source for plasma arc, power source for plasma arc, power source for motor, liquid pressure generator for liquid pressure cylinder, etc. are all installed with these control devices on the ground near the cutting work site. Are connected by cables and hoses (hereinafter collectively referred to as cables). It goes without saying that these cables, especially the power cable, have a waterproof structure in order to ensure insulation in water.
【０００６】[0006]
【発明が解決しようとする課題】ところで、上記のよう
な切断装置は、切断位置が大気中や、水中でも浅い部分
であれば問題なく高能率を発揮し、通常の作業において
は全く問題がなかったが、海水中や河川水中などの水深
25m 以上の深い位置で切断を行おうとすると、プラズマ
のパイロットアークが点火せず、切断が行えないという
問題点のあることが明らかとなった。By the way, the above-mentioned cutting device exhibits high efficiency without any problem if the cutting position is in the atmosphere or in a shallow portion in water, and there is no problem in normal work. The depth of seawater or river water
It became clear that there was a problem that the cutting could not be done because the pilot arc of the plasma did not ignite when cutting was attempted at a deep position of 25 m or more.
【０００７】これはパイロットアーク着火用の高周波高
電圧の電圧電流が伝達距離による減衰作用をうけ、充分
にトーチ部に伝達されないためで、水中においてとくに
この減衰が激しい。このため電源側でより高い電圧を発
生させても、それだけ損失分が増えるだけで有効到達エ
ネルギは増加せず、効果はほとんど見られなかった。本
発明はこうした問題点を解決し、大水深においても切断
できる水中切断技術を提供することを目的とする。This is because the high-frequency high-voltage voltage current for pilot arc ignition is attenuated by the transmission distance and is not sufficiently transmitted to the torch portion, and this attenuation is particularly severe in water. For this reason, even if a higher voltage is generated on the power supply side, the effective amount of energy does not increase and the effect is hardly seen because the amount of loss increases. An object of the present invention is to solve these problems and provide an underwater cutting technique capable of cutting even at a deep water depth.
【０００８】[0008]
【課題を解決するための手段】本発明は、プラズマアー
クを用いて水中の鋼材を切断する切断装置であって、該
プラズマアーク点火用パイロットアーク発生のための高
周波発生装置をプラズマトーチの近傍に設置したことを
特徴とする。SUMMARY OF THE INVENTION The present invention is a cutting device for cutting a steel material in water using a plasma arc, and a high frequency generator for generating a pilot arc for plasma arc ignition is provided near a plasma torch. It is characterized by being installed.
【０００９】[0009]
【作 用】本発明によれば、プラズマアーク点火用のパ
イロットアーク着火用電源である高周波、高電圧を発生
させる電源部分を切断装置本体に接近させて設置し、電
源部分とプラズマトーチとの水中における距離を短縮し
て、高周波、高電圧電流の水中における減衰を最小限度
としてプラズマアークの安定した着火を保持し、大水深
下における切断を可能とした。[Operation] According to the present invention, a power source part for generating high frequency and high voltage, which is a pilot arc ignition power source for plasma arc ignition, is installed close to the cutting device body, and the power source part and the plasma torch are submerged. By shortening the distance, the stable ignition of the plasma arc was maintained with the minimum attenuation of high frequency and high voltage current in water, and cutting under deep water was possible.
【００１０】[0010]
実施例１ 図１は本発明の第１の実施例の切断装置を示す。構成の
大半はさきに説明した図５の従来の装置と共通であり、
同一部分には同じ符号を用いているので詳細な説明は省
略する。相違しているのは、高周波発生装置16を切断装
置本体５のやや上方位置に支持台座３より高周波発生装
置用吊り索17で吊り下げて設置し、図示しない地上の電
源装置とこの高周波発生装置16との間は電源ケーブル15
で、高周波発生装置16と切断装置本体５との間は短い二
次ケーブル15a で結んだ点である。First Embodiment FIG. 1 shows a cutting device according to a first embodiment of the present invention. Most of the configuration is common to the conventional device of FIG. 5 described above,
The same reference numerals are used for the same parts, and detailed description thereof will be omitted. The difference is that the high-frequency generator 16 is installed at a position slightly above the cutting device main body 5 by being suspended from the support pedestal 3 by the high-frequency generator suspension ropes 17, and a power supply device on the ground (not shown) and this high-frequency generator. Power cable between 16 and 15
The high frequency generator 16 and the cutting device body 5 are connected by a short secondary cable 15a.
【００１１】高周波発生装置16の詳細を図２に示す。こ
の装置は防水型のケーシング16a 、変圧器16b 、導体ギ
ャップ16c により構成されているが、高周波の高電圧を
発生させる変圧器16b と導体ギャップ16c とは、従来の
装置では地上の電源装置に内蔵されていたもので、本発
明ではこれらをプラズマトーチに接近させるため分離
し、水中となるため防水型のケーシングに収めた。パイ
ロットアーク着火回路のスイッチが入ると高周波でかつ
高圧の電流がプラズマトーチ14の電極とノズルの間に作
用し、この間の気体流の絶縁状態が破壊されて雰囲気が
イオン化した電離状態、すなわちパイロットアークがオ
ンの状態となり、この瞬間に結果として被切断鋼材とプ
ラズマトーチ間の電気抵抗が大幅に低下し、パイロット
アークがメインアークに円滑に移行して切断が開始され
ることになる。The details of the high frequency generator 16 are shown in FIG. This device is composed of a waterproof casing 16a, a transformer 16b, and a conductor gap 16c.The transformer 16b and conductor gap 16c that generate high-frequency high voltage are built into the ground power supply device in the conventional device. However, in the present invention, these are separated in order to approach the plasma torch, and they are put in water, so that they are housed in a waterproof casing. When the pilot arc ignition circuit is turned on, a high-frequency and high-voltage current acts between the electrode and nozzle of the plasma torch 14, the insulating state of the gas flow is destroyed and the atmosphere is ionized, that is, the pilot arc. Is turned on, and as a result, the electric resistance between the steel material to be cut and the plasma torch is greatly reduced at this moment, and the pilot arc smoothly transfers to the main arc to start cutting.
【００１２】ちなみにパイロットアーク着火用の高周波
電流は、数百kHz 、電圧はトーチの水深にもよるが、た
とえば水深10m では数kV程度で、切断位置が深くなるほ
どプラズマ雰囲気ガスの電離が困難となるので高電圧を
必要とする。高周波、高電圧の電流は伝送中に減衰作用
を受ける。その程度は、伝達ケーブルの長さにもよる
が、水中では特に減衰が激しい。本発明者らの水中にお
ける実験によれば、高周波伝達ケーブルの長さは、５m
以内であれば減衰の問題はないが、これを越えると急激
に減衰が大となり、25m では数十％程度減衰してしま
う。By the way, the high frequency current for pilot arc ignition is several hundred kHz, and the voltage depends on the water depth of the torch. For example, at a water depth of 10 m, it is about several kV. As the cutting position becomes deeper, it becomes more difficult to ionize the plasma atmosphere gas. So need high voltage. High-frequency, high-voltage current is attenuated during transmission. The degree depends on the length of the transmission cable, but the attenuation is particularly strong underwater. According to the experiments by the present inventors in water, the length of the high frequency transmission cable is 5 m.
If it is within the range, there will be no problem of attenuation, but if it exceeds this, the attenuation will rapidly increase, and at 25 m, it will decrease by several tens of percent.
【００１３】なお、地上と切断装置との間にはパイロッ
トアーク着火用電源のほかにもケーブル類としてプラズ
マメインアーク用電源ケーブル、プラズマ雰囲気ガス、
シリンダ作動用液体、切断部排水用高圧空気等の各種流
体用ホースが連絡しているが、パイロットアーク着火用
電源以外のケーブル類には伝達距離による減衰の問題は
ないので、必ずしも前記の高周波発生装置16のケーシン
グ16a 内を経由させる必要はなく、経由させずに別途ケ
ーブル類を直結してもよい。In addition to the power source for pilot arc ignition, a power cable for plasma main arc, plasma atmosphere gas,
The hose for various fluids such as cylinder operating liquid and high pressure air for draining the cutting part is connected, but there is no problem of attenuation due to transmission distance in cables other than the power source for pilot arc ignition, so the above high frequency generation is not always required. It is not necessary to pass through the inside of the casing 16a of the device 16, and separate cables may be directly connected without passing through.
【００１４】この実施例は、以下の他の実施例と比較す
ると配線の中間に高周波発生装置16を取り付けるのみ
で、切断装置本体は従来のものをそのまま使用するか
ら、既存の装置を利用して大水深下における切断を行う
場合にその改造が容易である。 実施例２ 図３は本発明の切断装置の第２の実施例で、構成の大半
はさきに説明した図６の従来の装置と共通であり、同一
部分には同じ符号を用いているので詳細な説明は省略す
る。相違しているのは、高周波発生装置16を切断装置本
体５の上面に直接取り付けていることで、さきの実施例
に比較して高周波発生装置16を別個に吊り下げなくてよ
いから作業性が良く、プラズマトーチ14への二次ケーブ
ル15a も固定配線できるので故障のおそれがない。In this embodiment, compared with the other embodiments described below, only the high-frequency generator 16 is attached in the middle of the wiring, and the conventional cutting device is used as it is. It is easy to modify when cutting under deep water. Second Embodiment FIG. 3 shows a second embodiment of the cutting device of the present invention, and most of the configuration is common to the conventional device of FIG. 6 described above, and the same reference numerals are used for the same parts, so that details will be described. Detailed description is omitted. The difference is that the high-frequency generator 16 is directly attached to the upper surface of the cutting device body 5, so that the high-frequency generator 16 does not have to be individually hung as compared with the previous embodiment, so workability is improved. Since the secondary cable 15a to the plasma torch 14 can also be fixedly wired, there is no risk of failure.
【００１５】実施例３ 図４は本発明の切断装置の第３の実施例で、構成はさき
に例示した特開昭64-90317号公報記載の装置を改造した
ものである。この装置は鋼管矢板切断用のもので、この
ため本管Ｂ切断用のプラズマトーチ14のほかに継手管Ｃ
を切断するための砥石カッタ20を備え、かつ２種類の切
断手段の取り付け高さが異なるため切断装置本体５を上
下に２分割して上部ケーシング50、下部ケーシング51と
し、上部ケーシング50に対し下部ケーシング51が昇降で
きる昇降機構を備えているが、これらについては本発明
と直接関係しないので説明を省略する。改造点は高周波
発生装置16を上部ケーシング50の内部に直接取り付けて
いることで、第２の実施例と同様高周波発生装置16を別
個に吊り下げなくてよいから作業性が良く、プラズマト
ーチ14への二次ケーブル15a も固定配線できるので故障
のおそれがない。Embodiment 3 FIG. 4 shows a third embodiment of the cutting apparatus of the present invention, which is a modification of the apparatus described in Japanese Patent Application Laid-Open No. 64-90317 mentioned above. This device is for cutting steel pipe sheet piles. Therefore, in addition to plasma torch 14 for cutting main pipe B, joint pipe C
Equipped with a grindstone cutter 20 for cutting, and the cutting device main body 5 is divided into upper and lower parts into an upper casing 50 and a lower casing 51 because the mounting heights of the two kinds of cutting means are different, and the lower part with respect to the upper casing 50. Although the casing 51 is provided with an elevating mechanism capable of ascending and descending, these are not directly related to the present invention, and therefore description thereof is omitted. The modification is that the high-frequency generator 16 is directly attached to the inside of the upper casing 50, so that the high-frequency generator 16 does not have to be hung separately as in the second embodiment, so that the workability is good and the plasma torch 14 can be installed. Since the secondary cable 15a can also be fixedly wired, there is no risk of failure.
【００１６】以上の各実施例にみるように、高周波発生
装置16を地上の電源装置から分離してプラズマトーチ14
の近傍に設置したことが本発明の特徴であって、対象と
なる切断装置は上記の実施例のものに限定されるわけで
はなく、切断する鋼材も鋼管や鋼管矢板に限定されず、
本発明は大水深における水中であらゆる鋼材を切断する
任意のプラズマトーチに適用することができる。As shown in each of the above embodiments, the high frequency generator 16 is separated from the ground power supply device and the plasma torch 14 is separated.
It is a feature of the present invention that it is installed in the vicinity of, the target cutting device is not limited to those of the above embodiment, the steel material to be cut is not limited to the steel pipe or steel pipe sheet pile,
INDUSTRIAL APPLICABILITY The present invention can be applied to any plasma torch for cutting any steel material in water at a deep water depth.
【００１７】[0017]
【発明の効果】本発明によれば、プラズマアークの安定
した着火を保持し、大水深においても鋼材の切断が可能
である。According to the present invention, the stable ignition of the plasma arc can be maintained and the steel material can be cut even at a large water depth.
【図１】本発明の第一実施例の全体断面図である。FIG. 1 is an overall sectional view of a first embodiment of the present invention.
【図２】本発明の高周波発生装置の部分拡大図である。FIG. 2 is a partially enlarged view of the high frequency generator of the present invention.
【図３】本発明の第二実施例の全体断面図である。FIG. 3 is an overall sectional view of a second embodiment of the present invention.
【図４】本発明の第三実施例の全体断面図である。FIG. 4 is an overall sectional view of a third embodiment of the present invention.
【図５】従来の切断装置の全体断面図である。FIG. 5 is an overall sectional view of a conventional cutting device.
【図６】図５の切断装置本体部の部分拡大図である。6 is a partially enlarged view of the cutting device body of FIG.
１ 鋼管 ３ 支持台座 ４ 吊り索 ５ 切断装置本体 ８ 保持手段 14 プラズマトーチ 15 電源ケーブル 15a 二次ケーブル 16 高周波発生装置 16a ケーシング 16b 変圧器 16c 導体ギャップ 17 高周波発生装置用吊り索 1 Steel pipe 3 Support pedestal 4 Suspension line 5 Cutting device body 8 Holding means 14 Plasma torch 15 Power cable 15a Secondary cable 16 High frequency generator 16a Casing 16b Transformer 16c Conductor gap 17 Suspension line for high frequency generator
Claims (3)
断する切断装置であって、該プラズマアーク点火用パイ
ロットアーク発生のための高周波発生装置をプラズマト
ーチの近傍に設置したことを特徴とする鋼材の水中切断
装置。1. A cutting device for cutting steel material in water using a plasma arc, wherein a high frequency generator for generating a pilot arc for plasma arc ignition is installed in the vicinity of a plasma torch. Underwater cutting device.
生装置を、切断装置本体のやや上方の水中に吊り下げて
設置した請求項１記載の鋼材の水中切断装置。2. The underwater cutting apparatus for steel products according to claim 1, wherein a high frequency generator for generating a pilot arc is installed by being suspended in water slightly above the cutting apparatus body.
生装置を、切断装置本体に直接取り付けた請求項１記載
の鋼材の水中切断装置。3. The underwater cutting device for steel material according to claim 1, wherein a high-frequency generator for generating a pilot arc is directly attached to the main body of the cutting device.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3215037A JP2655955B2 (en) | 1991-08-27 | 1991-08-27 | Underwater cutting equipment for steel |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3215037A JP2655955B2 (en) | 1991-08-27 | 1991-08-27 | Underwater cutting equipment for steel |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0550234A true JPH0550234A (en) | 1993-03-02 |
| JP2655955B2 JP2655955B2 (en) | 1997-09-24 |
Family
ID=16665711
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP3215037A Expired - Fee Related JP2655955B2 (en) | 1991-08-27 | 1991-08-27 | Underwater cutting equipment for steel |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2655955B2 (en) |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2009256927A (en) * | 2008-04-15 | 2009-11-05 | Nippon Tetto Kogyo Kk | Boring device |
| CN102513645A (en) * | 2011-11-14 | 2012-06-27 | 中国石油大学(华东) | Deep water casing cutting device based on electric arc cutting |
| CN103215951A (en) * | 2013-05-11 | 2013-07-24 | 天津二十冶建设有限公司 | Method for underwater processing bridge deformed steel retaining cylinder |
| EP3617407A1 (en) * | 2018-09-03 | 2020-03-04 | Innogy SE | Decommissioning of foundation piles |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6475175A (en) * | 1987-09-18 | 1989-03-20 | Hitachi Ltd | Method and device for plasma cutting |
-
1991
- 1991-08-27 JP JP3215037A patent/JP2655955B2/en not_active Expired - Fee Related
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6475175A (en) * | 1987-09-18 | 1989-03-20 | Hitachi Ltd | Method and device for plasma cutting |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2009256927A (en) * | 2008-04-15 | 2009-11-05 | Nippon Tetto Kogyo Kk | Boring device |
| CN102513645A (en) * | 2011-11-14 | 2012-06-27 | 中国石油大学(华东) | Deep water casing cutting device based on electric arc cutting |
| CN102513645B (en) * | 2011-11-14 | 2015-06-03 | 中国石油大学(华东) | Deep water casing cutting device based on electric arc cutting |
| CN103215951A (en) * | 2013-05-11 | 2013-07-24 | 天津二十冶建设有限公司 | Method for underwater processing bridge deformed steel retaining cylinder |
| EP3617407A1 (en) * | 2018-09-03 | 2020-03-04 | Innogy SE | Decommissioning of foundation piles |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2655955B2 (en) | 1997-09-24 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| LAPS | Cancellation because of no payment of annual fees |