JPH0392138A - Heat insulating apparatus for static magnetic field-generating apparatus for mri - Google Patents
Heat insulating apparatus for static magnetic field-generating apparatus for mriInfo
- Publication number
- JPH0392138A JPH0392138A JP1229188A JP22918889A JPH0392138A JP H0392138 A JPH0392138 A JP H0392138A JP 1229188 A JP1229188 A JP 1229188A JP 22918889 A JP22918889 A JP 22918889A JP H0392138 A JPH0392138 A JP H0392138A
- Authority
- JP
- Japan
- Prior art keywords
- magnetic field
- magnetic
- heat insulating
- coil
- temp
- 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
- 230000003068 static effect Effects 0.000 title claims abstract description 14
- 239000011810 insulating material Substances 0.000 claims abstract description 8
- 238000005481 NMR spectroscopy Methods 0.000 claims abstract description 7
- 238000005259 measurement Methods 0.000 claims description 3
- 238000000034 method Methods 0.000 description 8
- 238000002595 magnetic resonance imaging Methods 0.000 description 5
- 230000020169 heat generation Effects 0.000 description 4
- 238000003384 imaging method Methods 0.000 description 4
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 2
- 229910052782 aluminium Inorganic materials 0.000 description 2
- 230000004907 flux Effects 0.000 description 2
- 238000009413 insulation Methods 0.000 description 2
- 238000001208 nuclear magnetic resonance pulse sequence Methods 0.000 description 2
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- 229920006328 Styrofoam Polymers 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000012774 insulation material Substances 0.000 description 1
- 235000000396 iron Nutrition 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000013421 nuclear magnetic resonance imaging Methods 0.000 description 1
- 239000008261 styrofoam Substances 0.000 description 1
- 239000002470 thermal conductor Substances 0.000 description 1
Landscapes
- Magnetic Resonance Imaging Apparatus (AREA)
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は、永久磁石方式ＭＲＩ装置、特にその磁気回路
の温度制御を行う断熱構造に関する。DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a permanent magnet MRI apparatus, and particularly to a heat insulating structure for controlling the temperature of a magnetic circuit thereof.
核磁気共鳴イメージング装置（以下ＭＲＩ装置と称する
）において永久磁石を使用した磁気回路は、周囲温度の
変化により磁場強度が変化するとの欠点がある。一般に
その温度係数は、−１０００ｐｐｍ／’Ｃ、即ち、温度
が１℃上がると、磁場強度は１０００ｐｐｍ弱くなる。A magnetic circuit using a permanent magnet in a nuclear magnetic resonance imaging apparatus (hereinafter referred to as an MRI apparatus) has a drawback in that the magnetic field strength changes with changes in ambient temperature. Generally, the temperature coefficient is -1000 ppm/'C, that is, when the temperature increases by 1C, the magnetic field strength weakens by 1000 ppm.
ＭＨＩ装置では、静磁界に傾斜磁界を加えて、位置を磁
界の大きさに対応さサ、位置に応じた共鳴周波数を発生
させる。In an MHI device, a gradient magnetic field is added to a static magnetic field, the position is adjusted to correspond to the magnitude of the magnetic field, and a resonant frequency corresponding to the position is generated.
この共鳴周波数を持っＮＭＲ信号を検出し、位置の特定
を行う。An NMR signal having this resonance frequency is detected and the position is specified.
然るに、静磁界の大きさが温度の影響を受けて変化する
と，結局、位置の特定に誤差を含むこととなる。更に位
置検出のずれは、面像の歪み、ぼけをも生む。However, if the magnitude of the static magnetic field changes due to the influence of temperature, an error will eventually be included in determining the position. Furthermore, the deviation in position detection also causes distortion and blurring of the surface image.
一般に、磁界の変化によって画像に影響を与える制限値
は、５ｐｐＩＩ１／時間であるとされる。この基準でゆ
くと，温度変化は、１時間に５／１０００℃以内に抑え
ることが必要となる。Generally, the limit value for influencing the image by changes in the magnetic field is 5 ppII1/hour. According to this standard, it is necessary to suppress the temperature change to within 5/1000°C per hour.
この一つの方法として，先に本発明者らは、特願昭６１
−１８５２７７及び特願昭６２−１１２３５８に記した
ように、磁気回路の周囲を断熱材でおおい、内部に、温
度調整用ヒータを設け、ヒータへの電流を制御して、磁
気回路温度を一定に保つ制御方法を提案している。As one method for this, the present inventors previously proposed
-185277 and Japanese Patent Application No. 62-112358, the magnetic circuit is surrounded by a heat insulating material, a temperature adjustment heater is provided inside, and the current to the heater is controlled to keep the magnetic circuit temperature constant. We are proposing a control method to maintain
また、このとき用いる傾斜磁場コイルとしては種々のも
のが提案されているが、本発明者らが、先に出願した，
特願昭６１− ２０７９３０に記載したものが適してい
る，
ところで、最近のＭＲＩ装置には、高速撮像患者スルー
プットの向上が要求されており，これに伴ない、グラジ
エントエコー法など、新しい高速シーケンスが用いられ
るようになった。このシーケンスは、従来のスピンエコ
ー法と異なり、スピンの結像に１８０” ＲＦパルスを
用いず，傾斜磁場の反転を利用するものである。従って
，傾斜磁場コイルに印加される電流も大きく、使用頻度
（デュテイ）も高くなってきた。傾斜磁場コイルは、基
本的には、銅線から構威されているので、有限の電気抵
抗値を持っている．従って、傾斜磁場を形成するためコ
イルに電流を流すと、そこで熱が電流の二乗に比例して
発生する。In addition, various gradient magnetic field coils have been proposed for use in this case, but the present inventors have previously filed an application,
The one described in Japanese Patent Application No. 61-207930 is suitable. Incidentally, recent MRI apparatuses are required to improve high-speed imaging patient throughput, and along with this, new high-speed sequences such as gradient echo method are being developed. came to be used. This sequence differs from the conventional spin echo method in that it does not use 180" RF pulses to image spins, but instead utilizes the reversal of the gradient magnetic field. Therefore, the current applied to the gradient magnetic field coils is also large, making it difficult to use. The frequency (duty) has also increased.Gradient magnetic field coils are basically constructed from copper wire, so they have a finite electrical resistance value.Therefore, in order to form gradient magnetic fields, it is necessary to When a current is passed through it, heat is generated in proportion to the square of the current.
上記従来技術（特願昭６１−１８５２７７）は，傾斜磁
場コイルの発熱の点には配慮しておらず、後述する断熱
材でおおって形成する断熱部の内部に配置していた。従
って、コイルで発生した熱が，近傍の磁極片を介して永
久磁石に伝わり，永久磁石の温度を上昇させ．結果的に
核磁気共鳴周波数を変化させる要因となっていた。The above-mentioned prior art (Japanese Patent Application No. 61-185277) does not take into consideration the heat generation of the gradient magnetic field coil, and instead places the gradient magnetic field coil inside a heat insulating section covered with a heat insulating material, which will be described later. Therefore, the heat generated by the coil is transferred to the permanent magnet via the nearby magnetic pole piece, raising the temperature of the permanent magnet. As a result, it became a factor that changed the nuclear magnetic resonance frequency.
本発明の目的は、傾斜磁場コイルが大電流、高デュテイ
で使用されたときにおいても，その熱が．永久磁石に伝
わりにくい構成とすることにより、磁気回路の温度を目
標とする温度に常に制御することにある。The purpose of the present invention is to prevent heat generation even when gradient magnetic field coils are used with large current and high duty. The purpose is to constantly control the temperature of the magnetic circuit to a target temperature by having a configuration that does not easily transmit the magnetic force to the permanent magnet.
本発明は，Ｄ止磁界用の磁気回路と、該磁気回路′全体
を被覆する断熱部と、該断熱部に埋め込んだ温度調整可
能なヒータ部とを備えた。The present invention includes a magnetic circuit for the D stopping field, a heat insulating part that covers the entire magnetic circuit, and a temperature-adjustable heater part embedded in the heat insulating part.
また、上記目的を達或するため、傾斜磁場コイルの配置
を断熱部の外側とした。Furthermore, in order to achieve the above object, the gradient magnetic field coils are arranged outside the heat insulating section.
〔作用）
本発明では、ヒータに目標値と周囲温度との差分の信号
相当の電流を印加し、目標値になるように温度調整が可
能となる。更に、断熱部は、周囲温度の影響を磁気回路
に極力与えないように働く。[Function] According to the present invention, a current corresponding to a signal of the difference between the target value and the ambient temperature is applied to the heater, and the temperature can be adjusted so as to reach the target value. Furthermore, the heat insulating section works to minimize the influence of ambient temperature on the magnetic circuit.
傾斜磁場コイルが断熱部の外部に配置されているので、
コイルの発熱が内部変動要因とならず、高精度な温度制
御が可能となる。Since the gradient magnetic field coils are placed outside the insulation section,
The heat generated by the coil does not become a factor of internal fluctuations, allowing highly accurate temperature control.
以下，本発明の一実施例を添付図面にもとづいて説明す
る。Hereinafter, one embodiment of the present invention will be described based on the accompanying drawings.
第１図は、本発明に係るＭＲＩ装置の静磁場発生装置を
含む磁石ガントリ部全体の構或を示す斜視図であり、分
かりやすくするため内部を一部開示している。まず、静
磁界発生装置である永久磁石を用いた磁気回路について
説明する。すなわち、第１図において、一対の永久磁石
１ａ，ｌｂは、両者間に被検体が入り得る空隙Ａを形威
して上下に対向配置されている。これらの永久磁石１ａ
，１ｂは、上記空隙Ａ内に静磁場を発生するためのもの
で、例えば，形状が円盤に形成されており、それぞれ上
下の継鉄２ａ，２ｂによって支持されている。これらの
継鉄２ａ，２ｂは、上記永久磁石１ａ，ｌｂ及び後述の
磁極片５ａ，５ｂを所定の間隔をあけて対向配置すると
共に磁路を形成するもので、例えば横幅よりも奥行きの
方が短い長方形に形成されている。FIG. 1 is a perspective view showing the entire structure of a magnet gantry section including a static magnetic field generator of an MRI apparatus according to the present invention, and a portion of the inside is shown for clarity. First, a magnetic circuit using a permanent magnet, which is a static magnetic field generator, will be explained. That is, in FIG. 1, a pair of permanent magnets 1a and lb are arranged vertically to face each other with a gap A between them in which a subject can enter. These permanent magnets 1a
, 1b are for generating a static magnetic field within the gap A, and are formed, for example, in the shape of a disk, and are supported by upper and lower yokes 2a and 2b, respectively. These yokes 2a, 2b have the permanent magnets 1a, lb and magnetic pole pieces 5a, 5b (described later) facing each other at a predetermined interval and form a magnetic path.For example, the depth is larger than the width. It is formed into a short rectangle.
上記上下の継鉄２ａ，２ｂは、複数の縦の継鉄３，３・
・・によって対向支持されている。これらの縦の継鉄３
は、上下の継鉄２ａ，２ｂを所定の間隔をあけて対向配
置すると共に上記永久磁石１ａ，１ｂによる磁路を閉じ
させるもので、内部に磁束を通しやすい部材で形成され
、例えば上下の継鉄２ａ，２ｂの四隅に一本ずつ合計四
本立設されており、上記空隙Ａ内に設定された計測空間
を通る磁束の戻り回路をそれぞれ形成している。上記一
対の永久磁石１ａ，ｌｂの空隙Ａ側の対向面には、それ
ぞれ磁極片５ａ，５ｂが磁気的及び機械的に固着されて
いる。これらの磁極片５ａ，５ｂは、上記空隙Ａ内の所
定の領域に設定されると共に、被検体の検査部位が入る
計測空間における静磁場の均一性を高めるものであり、
略円盤状に形成され、その周縁部に環状突起を設けて構
威されている。（第２図も参照）
本実施例では、前記磁気回路全体を断熱材，たとえば発
泡スチロールやスポンジ体など６０でおおって断熱部（
断熱カバー）６を形成する。ただし、被検体が均一空間
に入れるよう、中央部は開口された形の断熱部としてい
る。さらに第１図には、ＭＲ４装置として必要なガント
リカバー７０ａ〜ｄを示しているが，これらガントリ力
バーは、前面用７０ａ，後面用７０ｂ，側面用７０ｃ，
上面用７０ｄより構成され、上記断熱カバー６の外側に
配置される。The above-mentioned upper and lower yokes 2a, 2b are composed of a plurality of vertical yokes 3, 3.
It is supported by... These vertical yokes 3
The upper and lower yokes 2a and 2b are arranged facing each other at a predetermined interval, and the magnetic path formed by the permanent magnets 1a and 1b is closed.The upper and lower yokes 2a and 2b are made of a material that easily allows magnetic flux to pass through the inside. A total of four poles are erected, one at each of the four corners of the irons 2a and 2b, each forming a return circuit for magnetic flux passing through the measurement space set within the air gap A. Magnetic pole pieces 5a and 5b are magnetically and mechanically fixed to opposing surfaces of the pair of permanent magnets 1a and lb on the air gap A side, respectively. These magnetic pole pieces 5a and 5b are set in a predetermined area within the air gap A, and are used to improve the uniformity of the static magnetic field in the measurement space where the test part of the subject enters.
It is formed approximately in the shape of a disk, and is provided with an annular protrusion on its periphery. (See also FIG. 2.) In this embodiment, the entire magnetic circuit is covered with a heat insulating material such as styrofoam or sponge body 60, and the heat insulating part (
A heat insulating cover) 6 is formed. However, the central part is an open heat insulating part so that the subject can be placed in a uniform space. Further, FIG. 1 shows gantry covers 70a to 70d necessary for the MR4 device, and these gantry force bars are 70a for the front, 70b for the rear, 70c for the side,
The upper surface 70d is arranged outside the heat insulating cover 6.
次に、断熱部の詳細及び、傾斜磁場コイル、照射コイル
、受信コイルについて、第１図の断熱部をより詳細に示
した、第２図及び第３図を用いて説明する。第２図の実
施例の断熱部の断面を含む斜視図であり、第３図は，同
縦断面図である。Next, the details of the heat insulating section, the gradient magnetic field coil, the irradiation coil, and the receiving coil will be explained using FIGS. 2 and 3, which show the heat insulating section in FIG. 1 in more detail. FIG. 3 is a perspective view including a cross section of the heat insulating part of the embodiment shown in FIG. 2, and FIG. 3 is a longitudinal sectional view thereof.
断熱部６の内側には、空隙Ａ面に面する面を除いてアル
ミ板８が貼りつけてある．アルミ板８の内側には、絶縁
物でおおわれた保温用の面状ヒーター７が固定されてい
る。被検体が入る空隙Ａ側の断熱材６１ａ，６ｌｂは、
傾斜磁場コイル３１ａ，３↓ｂと、磁極片５ａ，５ｂと
の間に配置してある。これにより、傾斜磁場コイルで発
生する熱は、磁極片及び、永久磁石１ａ，ｌｂに伝わら
ない。An aluminum plate 8 is attached to the inside of the heat insulating part 6 except for the surface facing the gap A side. A sheet heater 7 for heat retention covered with an insulating material is fixed inside the aluminum plate 8. The insulation materials 61a and 6lb on the side of the gap A where the subject enters are as follows:
It is arranged between the gradient magnetic field coils 31a, 3↓b and the magnetic pole pieces 5a, 5b. Thereby, the heat generated in the gradient magnetic field coils is not transmitted to the magnetic pole pieces and the permanent magnets 1a, lb.
なお、傾斜磁コイル３１ａ，３ｌｂは非熱伝導体のネジ
８０により磁極片５ａ，５ｂに取付けられる。本実施例
で用いる傾斜磁場コイルとしては、たとえば本発明者ら
が提案した特願昭６１− ２０７９３０が使用できる。Incidentally, the gradient magnetic coils 31a, 3lb are attached to the magnetic pole pieces 5a, 5b by screws 80 made of a non-thermal conductor. As the gradient magnetic field coil used in this embodiment, for example, Japanese Patent Application No. 61-207930 proposed by the present inventors can be used.
傾斜磁場コイル３１ａ，３ｌｂの内側には、被検体にＮ
ＭＲ現象を起こさせるための照射コイル３２が配置され
ている。さらにその内側には、被検体からのＮＭＲ信号
を受信する受信コイル３３を設けてある。Inside the gradient magnetic field coils 31a and 3lb, N is applied to the subject.
An irradiation coil 32 is arranged to cause the MR phenomenon. Further inside thereof, a receiving coil 33 is provided to receive the NMR signal from the subject.
磁気回路を目標温度に一定に保つ方法については、複数
の温度調整用ヒータ７と温度センサ（図示せず）、保温
用電源（図示せず）を用いて、断熱部６内を一定とする
が、その詳細は、本発明者らが出願した特願昭６１−１
８５２７７に記載した方怯と同じものを用いている。Regarding the method of keeping the magnetic circuit at a constant target temperature, the inside of the heat insulating part 6 is kept constant using a plurality of temperature adjustment heaters 7, temperature sensors (not shown), and a heat retention power source (not shown). , the details of which can be found in the patent application filed by the present inventors in 1986-1.
The same method as described in 85277 is used.
次に傾斜磁場コイル３１の発熱について述べる。Next, the heat generation of the gradient magnetic field coil 31 will be described.
実施例の傾斜磁場コイル３ｌは、第２図に示すように一
対の配置されるが、これは直交するＸ，Ｙ，Ｚ３方尚の
コイルより構或されている。それらのコイルの電気抵抗
値は、たとえば０．１〜１Ω程度である。ここでの発熱
は、前述の使用するパルスシーケンスにより決められる
が、最近は、高速撮像法の一つであるグラジエントエコ
ー法が多用されるが、電流値として十数アンペア、パル
スのデューテイも５０％前後と高いものであるので、傾
斜磁場コイル３１での発熱は数十ワット程度となる。The gradient magnetic field coils 3l of the embodiment are arranged in a pair as shown in FIG. 2, and are composed of coils in three orthogonal directions, X, Y, and Z. The electrical resistance value of these coils is, for example, about 0.1 to 1 Ω. The heat generation here is determined by the pulse sequence used as described above, and recently, the gradient echo method, which is one of the high-speed imaging methods, is often used, but the current value is more than 10 amperes and the pulse duty is 50%. Since the gradient magnetic field coil 31 generates a large amount of heat, the amount of heat generated in the gradient magnetic field coil 31 is approximately several tens of watts.
本発明によれば、上記傾斜磁場コイルで発生した熱は、
断熱部内にこもることがなく、カントリ外部へ放熱され
る。従って、
（１）ＭＲＩ撮像のためのパルスシーケンスにより、傾
斜磁場コイルに印加される電流によって発生する熱が，
断熱部６内に局所的に発生することがなくなり、磁気回
路の保温制御がより高精度で実現できるようになった。According to the present invention, the heat generated by the gradient magnetic field coil is
Heat is radiated to the outside of the country without being trapped inside the insulation part. Therefore, (1) Due to the pulse sequence for MRI imaging, the heat generated by the current applied to the gradient magnetic field coil is
This does not occur locally within the heat insulating section 6, making it possible to control the heat retention of the magnetic circuit with higher precision.
（２）よって、永久磁石方式ＭＨＩ装置において、グラ
ジエントエコー法など高速撮像で、良好な画像を提供で
きるようになった。(2) Therefore, in the permanent magnet type MHI device, it has become possible to provide good images by high-speed imaging such as the gradient echo method.
第１図は本発明の一実施例の斜視図、第２図は、第ｌ図
の断熱部を詳細に示した斜視図、第３図は、第２図の縦
断面図である。
１・・・永久磁石，２・・・継鉄，３・・・縦の継鉄、
５・・・磁極片、６・・・断熱部、７・・・温度調整用
ヒータ、６ｏ・・断熱材、６１ａ，６ｌｂ・・・空隙Ａ
面側断熱材、３１・・・傾斜磁場コイル、３２・・・照
射コイル、３３・・受信コイル。1 is a perspective view of one embodiment of the present invention, FIG. 2 is a perspective view showing details of the heat insulating section of FIG. 1, and FIG. 3 is a longitudinal sectional view of FIG. 2. 1...Permanent magnet, 2...Yoke, 3...Vertical yoke,
5... Magnetic pole piece, 6... Heat insulating part, 7... Heater for temperature adjustment, 6o... Heat insulating material, 61a, 6lb... Gap A
Surface side heat insulating material, 31... Gradient magnetic field coil, 32... Irradiation coil, 33... Receiving coil.
Claims (1)
磁極片と永久磁石と磁路とより成る静磁界用磁気回路と
、上記均一磁界に加算する傾斜磁界を発生する傾斜磁場
コイルと、測定空間内の被検体に核磁気共鳴を起させる
周波数の電磁波を印加する照射コイルと、上記被検体か
らの核磁気共鳴信号を受信する受信コイルと、を備える
と共に、上記静磁界用磁気回路の周囲を断熱材でおおつ
て断熱部を形成し、かつ該断熱部の内部に、温度調整用
ヒータを備え、上記各ヒータへの電流を制御して静磁界
用磁気回路の温度を目標温度に設定させる制御手段を設
けてなるが、上記傾斜磁場コイルを該断熱部の外部へ配
置したことを特徴とするＭＲＩ用静磁界発生装置。1. A static magnetic field magnetic circuit consisting of a magnetic pole piece, a permanent magnet, and a magnetic path for generating a uniform magnetic field, which face each other across a measurement space, and a gradient magnetic field coil that generates a gradient magnetic field to be added to the uniform magnetic field; An irradiation coil that applies an electromagnetic wave with a frequency that causes nuclear magnetic resonance to a subject in space, and a receiving coil that receives a nuclear magnetic resonance signal from the subject, and a surrounding area of the static magnetic field magnetic circuit. is covered with a heat insulating material to form a heat insulating part, and a temperature adjusting heater is provided inside the heat insulating part, and current to each of the heaters is controlled to set the temperature of the static magnetic field magnetic circuit to a target temperature. A static magnetic field generator for MRI, comprising a control means, and wherein the gradient magnetic field coil is disposed outside the heat insulating section.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1229188A JP2857888B2 (en) | 1989-09-06 | 1989-09-06 | Permanent magnet MRI system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1229188A JP2857888B2 (en) | 1989-09-06 | 1989-09-06 | Permanent magnet MRI system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0392138A true JPH0392138A (en) | 1991-04-17 |
| JP2857888B2 JP2857888B2 (en) | 1999-02-17 |
Family
ID=16888186
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1229188A Expired - Lifetime JP2857888B2 (en) | 1989-09-06 | 1989-09-06 | Permanent magnet MRI system |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP2857888B2 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2007330791A (en) * | 2006-06-12 | 2007-12-27 | Siemens Ag | Method of controlling temperature between magnetic field components of magnetic resonance system |
| CN108860568A (en) * | 2017-05-09 | 2018-11-23 | 波音公司 | The thermal insulation of aircraft component and its assembling and application method |
-
1989
- 1989-09-06 JP JP1229188A patent/JP2857888B2/en not_active Expired - Lifetime
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2007330791A (en) * | 2006-06-12 | 2007-12-27 | Siemens Ag | Method of controlling temperature between magnetic field components of magnetic resonance system |
| CN108860568A (en) * | 2017-05-09 | 2018-11-23 | 波音公司 | The thermal insulation of aircraft component and its assembling and application method |
| CN108860568B (en) * | 2017-05-09 | 2024-02-09 | 波音公司 | Thermal insulation for aircraft components and methods of assembly and use thereof |
Also Published As
| Publication number | Publication date |
|---|---|
| JP2857888B2 (en) | 1999-02-17 |
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