JPH0223837B2 - - Google Patents
Info
- Publication number
- JPH0223837B2 JPH0223837B2 JP58082972A JP8297283A JPH0223837B2 JP H0223837 B2 JPH0223837 B2 JP H0223837B2 JP 58082972 A JP58082972 A JP 58082972A JP 8297283 A JP8297283 A JP 8297283A JP H0223837 B2 JPH0223837 B2 JP H0223837B2
- Authority
- JP
- Japan
- Prior art keywords
- putty
- grease
- composition
- radiation shielding
- weight
- 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.)
- Expired - Lifetime
Links
Classifications
-
- G—PHYSICS
- G21—NUCLEAR PHYSICS; NUCLEAR ENGINEERING
- G21F—PROTECTION AGAINST X-RADIATION, GAMMA RADIATION, CORPUSCULAR RADIATION OR PARTICLE BOMBARDMENT; TREATING RADIOACTIVELY CONTAMINATED MATERIAL; DECONTAMINATION ARRANGEMENTS THEREFOR
- G21F1/00—Shielding characterised by the composition of the materials
- G21F1/02—Selection of uniform shielding materials
- G21F1/026—Semi-liquids, gels, pastes
Landscapes
- Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- High Energy & Nuclear Physics (AREA)
- Sealing Material Composition (AREA)
Description
本発明は放射線遮蔽パテ状組成物に関する。
原子力発電所の室壁や器壁を電線や配管が貫通
する空隙部ほか種々の空隙からの放射線の漏洩を
防止するために、従来、鉛毛を直接にかかる空隙
部に充填し、或いは鉛毛を袋詰めにしてこれを空
隙に充填することが行なわれている。しかし、こ
の方法によれば、空隙に鉛毛を充填する作業が煩
雑であり、しかも、空隙への鉛毛の充填率は精々
50％程度であるので、空隙を気密的に封止するこ
とができない。一方、鉛粉を含有する硬化性樹脂
組成物も知られている。一般に、放射線遮蔽効果
は、充填された遮蔽材の密度と厚さの積で定義さ
れる面密度に比例することが知られているが、上
記組成物を適用後に硬化し得るように、鉛粉末の
含有量が限られるので、空隙への適用は比較的簡
単であつても、放射線遮蔽性は尚不十分である。
しかも硬化後には容易にこれを除去することがで
きず、硬化後に電線や配管を増設する場合に支障
を来すことがある。
本発明は上記したような放射線の遮蔽における
問題を解決するためになされたものであつて、例
えば密度の大きい金属又は金属酸化物粉末のよう
な無機粉末を高含有量で含有して、放射線遮蔽効
果にすぐれると共に、パテ状であるため任意形状
の空隙への適用が簡単で、しかも、適用後の形態
保持性にすぐれ、更に、非硬化性であるために適
用後にも必要に応じて容易に除去することができ
る放射線遮蔽パテ状組成物を提供することを目的
とする。
本発明による放射線遮蔽パテ状組成物は、グリ
ース及びポリブテンから選ばれる少なくとも１種
からなり、25℃における粘度が104センチストー
クス以上からJIS K2220−1980による稠度が100
以上のバインダー100重量部について、350メツシ
ユ篩を93％以上パスする鉛微粉末1300〜2000重量
部と、繊維0.1〜50重量部とを含有し、且つ、非
硬化性であることを特徴とする。
本発明において用いるバインダーは、グリース
及びポリブテンから選ばれる少なくとも１種から
なり、25℃における粘度が104センチストークス
以上からJIS K2220−1980による稠度が10以上の
範囲にある粘稠なものである。25℃における粘度
が104センチストークスよりも小さいときは、自
己形態保持性を有するパテ状組成物を形成し難
く、一方、上記稠度が100よりも小さいときは、
放射線遮蔽効果を有するに足る十分な量の鉛微粉
末を組成物中に含有させた場合に、かかる組成物
がパテとして一体にまとまり難いからである。好
ましくは、バインダーは25℃における粘度が105
センチストークス以上から上記稠度が150以上、
特に好ましくは上記粘度が２×105センチストー
クス以上から上記稠度が200以上の範囲にある。
グリースは一般に天然若しくは合成の油状分散
媒、即ち、基油に増稠剤を分散させた常温で粘稠
な液状又は半固体物質であつて、通常、油状の潤
滑剤に対して潤滑グリース又は単にグリースと称
される。上記基油としては、例えは、トランス
油、スピンドル油、ケーブル油、絶縁油、機械油
等の石油系油、ロジン油、ヒマシ油、オリーブ
油、鯨油等の天然油、ポリブテン、塩素化パラフ
イン、ポリエチレングリコール等の合成重合体油
等が用いられ、また、増稠剤としては、例えば、
脂肪酸のバリウム、ストロンシウム、亜鉛、鉛、
カドミウム、カリルム、ナトリウム、カルシウ
ム、リチウム、アルミニウム等の金属塩である金
属石ケンのほか、非石ケン系としてベントナイ
ト、シリカゲル、銅フタロシアニン等が用いられ
る。勿論、上記した増稠剤の任意の２以上の混合
物も用いられる。
かかるグリースの具体例として、例えば、石ケ
ン系グリースとしてナトリウム石ケングリース、
カルシウム石ケングリース、リチウム石ケングリ
ース、アルミニウム石ケングリース、バリウム石
ケングリースを、また、非石ケン系グリースとし
て、ベントナイトグリース、シリカゲルグリース
等を挙げることができるが、特に、リチウム石ケ
ングリース、アルミニウム石ケングリース、ベン
トナイトグリース、シリカゲルグリース等が組成
物の形態保持性にすぐれるところから好ましく用
いられる。しかし、上記のほか、一般に知られて
いるグリース、例えば、堀口博著「潤滑油とグリ
ース」（三共出版(株)昭和45年発行）第402〜419頁
に記載されているグリースも用いることができ
る。
本発明による放射線遮蔽パテ状組成物は、上記
バインダー100重量部について、鉛微粉末を1300
〜2000重量部の範囲で含有する。本発明によれ
ば、かかる範囲で鉛微粉末を含有されることによ
つて、非常に高い放射線遮蔽効果を確保しつつ、
得られる組成物をパテ状に保つことができる。
また、鉛微粉末は、組成物中に上記のように多
量に含有させるために、その粒度が小さいことを
要し、本発明においてはJIS標準篩による350メツ
シユ篩を93％以上パスする微粉末のものが用いら
れる。
更に、本発明による放射線遮蔽パテ状組成物
は、これを所要の箇所に適用した後、長期にわた
つてその形状を保持させるために、バインダー
100重量部について繊維を0.1〜50重量部、好まし
くは１〜20重量部を含有する。ここに、繊維は無
機繊維でも有機繊維でもよいが、上記した理由か
ら繊維は、その直径が100μｍ以下、特に0.05〜
50μｍの範囲にあり、平均長さが0.1〜50mmの範囲
にあるのが望ましい。かかる繊維としては、無機
繊維も有機繊維も用いることができ、無機繊維と
しては、例えば、石綿、ロツクウール、ガラスウ
ール、炭素繊維、鉄、銅等の金属繊維を挙げるこ
とができ、また、有機繊維としては、例えば、ポ
リアミド繊維、フツ素樹脂繊維、フエノール系繊
維等を挙げることができるが、これらに限定され
るものではない。組成物に余りに多量の繊維を含
有させれば、組成物がパテ状に呈しなくなるので
好ましくはない。
本発明によるパテ状組成物は、上記したバイン
ダー、鉛微粉末及び繊維のほかに、必要に応じ
て、その他の充填剤、例えば、水酸化アルミニウ
ムのような難燃剤を適宜量含有させて難燃性を付
与することもでき、また、着色剤を含有させて着
色することもできる。
尚、本発明による放射線遮蔽パテ状組成物は、
その製造方法において何ら制限されないが、例え
ば、所要の成分をニーダー、ロール等の通常の方
法にて均一に混練することにより得ることができ
る。
上記のような組成を有する本発明の放射線遮蔽
パテ状組成物は、通常、JIS A5752に規定する軟
度が常温で１〜25（１mm）の範囲にあり、好まし
くは３〜18の範囲にあり、密度は４以上、好まし
くは６以上である。
本発明においては、上記の物性を満足する範囲
であれば、ジオクチルフタレートのような塩化ビ
ニル樹脂用の可塑剤や、その他の合成樹脂、ゴム
用の配合剤を含有されることもできる。
本発明による放射線遮蔽パテ状組成物は、この
ように密度の大きい鉛微粉末の高含有量にて含有
して、放射線遮蔽効果にすぐれると共に、このよ
うに密度が大きい組成物にかかわらずにパテ状を
呈し、かくして、放射線漏洩の原因となる任意の
形状の空隙部への適用が容易であり、しかも、非
硬化性であるので、適用後は硬化等の後処理を要
しない。更に、一旦、適用した後は、長期にわた
つてその形状を保持するが、必要に応じて、容易
に除去することもできる。また、加熱減量も殆ど
認められない。
以下に実施例を挙げて本発明を説明するが、本
発明はこれら実施例により何ら限定されるもので
はない。尚、組成物の放射線遮蔽効果は、前記し
たように、一般にその面密度に比例することが知
られているので、実施例には密度を挙げるに留め
た。
実施例
表に示す成分をロールで混練して、本発明によ
る放射線遮蔽パテ状組成物を調製した。これらは
いずれも鉛微粉末ほか金属酸化物粉末を多量に含
有し、表に示すように、密度の大きい組成物であ
りながら、適度の軟度と良好な自己形態保持性を
有し、従つて、適用性又は施工性はすぐれると共
に、非硬化性を有し、施工後の除去も容易であ
る。
尚、表におけるパテ特性のうち、自己形態保持
性の評価は次による。即ち、組成物を手にて十分
に捏ねて約１cm立方の立方体を作る際の容易さを
評価すると共に、得られた立方体の形態の安定性
を５段階評価した。
Ｓ…パテとしてまとまりが良好であり、適度の軟
度を有するために立方体への成形が容易であ
り、且つ、立方体の形態も非常に安定に保持さ
れる。
Ｅ…パテとしてのまとまりはＳに比べて僅かに劣
るが、立方体への成形性及びその安定性にもす
ぐれている。
Ｇ…パテとしてのまとまりを有し、また、立方体
への成形性と安定性も実用的には十分である。
Ｆ…パテとしてのまとまりを一応有し、立方体に
成形することもできるが、この立方体は僅かな
外力によつてもその形態がくずれる。
Ｐ…流動性が過度に大きく、パテとしてのまとま
りを有さないために、立方体に成形することが
困難である。
また、非硬化性は、組成物を常温で１か月間放
置した後の軟度変化が3.0以内を良とした。
The present invention relates to a radiation shielding putty-like composition. In order to prevent the leakage of radiation from various voids such as the voids where electric wires and piping pass through the chamber walls and vessel walls of nuclear power plants, lead wool has traditionally been filled directly into the voids, or The practice is to pack the materials into bags and fill the voids with them. However, according to this method, the work of filling the voids with lead hairs is complicated, and the filling rate of lead hairs into the voids is at most low.
Since it is about 50%, the void cannot be hermetically sealed. On the other hand, curable resin compositions containing lead powder are also known. It is generally known that the radiation shielding effect is proportional to the areal density defined as the product of the density and thickness of the filled shielding material. Since the content of is limited, even though it is relatively easy to apply to voids, the radiation shielding property is still insufficient.
Moreover, it cannot be easily removed after hardening, which may cause problems when adding electric wires or piping after hardening. The present invention has been made in order to solve the above-mentioned problems in shielding radiation. In addition to being highly effective, it is putty-like so it can be easily applied to voids of any shape, and it retains its shape well after application.Furthermore, since it is non-hardening, it can be easily applied as needed after application. The object of the present invention is to provide a radiation shielding putty-like composition that can be removed. The radiation shielding putty-like composition according to the present invention is composed of at least one selected from grease and polybutene, and has a viscosity of 104 centistokes or more at 25°C and a consistency of 100 centistokes or more according to JIS K2220-1980.
100 parts by weight of the above binder contains 1,300 to 2,000 parts by weight of fine lead powder that passes 93% or more of a 350 mesh sieve, and 0.1 to 50 parts by weight of fiber, and is characterized by being non-hardening. . The binder used in the present invention is composed of at least one selected from grease and polybutene, and is a viscous binder having a viscosity at 25° C. of 10 4 centistokes or more and a consistency of 10 or more according to JIS K2220-1980. When the viscosity at 25°C is less than 10 4 centistokes, it is difficult to form a putty-like composition with self-shape retention; on the other hand, when the consistency is less than 100,
This is because when a composition contains a sufficient amount of fine lead powder to have a radiation shielding effect, the composition is difficult to be putty together. Preferably, the binder has a viscosity of 10 5 at 25°C.
From centistokes or higher to the above consistency of 150 or higher,
Particularly preferably, the viscosity is in the range of 2×10 5 centistokes or more and the consistency is in the range of 200 or more. Grease is generally a natural or synthetic oily dispersion medium, i.e., a base oil with a thickener dispersed in it, and is a viscous liquid or semi-solid substance at room temperature. It is called grease. Examples of the base oil include petroleum oils such as transformer oil, spindle oil, cable oil, insulating oil, and machine oil, natural oils such as rosin oil, castor oil, olive oil, and whale oil, polybutene, chlorinated paraffin, and polyethylene. Synthetic polymer oils such as glycol are used, and as thickeners, for example,
Fatty acids barium, strontium, zinc, lead,
In addition to metal soaps that are metal salts of cadmium, potassium, sodium, calcium, lithium, aluminum, etc., bentonite, silica gel, copper phthalocyanine, etc. are used as non-soap soaps. Of course, mixtures of any two or more of the above-mentioned thickeners may also be used. Specific examples of such grease include, for example, sodium soap grease as soap-based grease;
Calcium soap grease, lithium soap grease, aluminum soap grease, barium soap grease, and non-soap greases include bentonite grease, silica gel grease, etc. In particular, lithium soap grease, Aluminum soap grease, bentonite grease, silica gel grease, etc. are preferably used because they have excellent shape retention properties of the composition. However, in addition to the above, commonly known greases such as those described in "Lubricating Oil and Grease" by Hiroshi Horiguchi (published by Sankyo Publishing Co., Ltd. in 1972), pages 402 to 419, can also be used. can. The radiation shielding putty-like composition according to the present invention contains 1300 parts by weight of fine lead powder per 100 parts by weight of the binder.
Contained in the range of ~2000 parts by weight. According to the present invention, by containing fine lead powder in this range, a very high radiation shielding effect is ensured, and
The resulting composition can be kept in the form of a putty. In addition, the lead fine powder must have a small particle size in order to be contained in a large amount in the composition as described above. are used. Further, the radiation shielding putty-like composition according to the present invention is coated with a binder in order to maintain its shape for a long period of time after being applied to a desired location.
It contains 0.1 to 50 parts by weight, preferably 1 to 20 parts by weight of fiber per 100 parts by weight. Here, the fibers may be inorganic fibers or organic fibers, but for the reasons mentioned above, the fibers have a diameter of 100 μm or less, especially 0.05 μm or less.
Preferably, the average length is in the range of 50 μm, and the average length is in the range of 0.1 to 50 mm. As such fibers, both inorganic fibers and organic fibers can be used. Examples of inorganic fibers include asbestos, rock wool, glass wool, carbon fibers, metal fibers such as iron and copper, and organic fibers. Examples of the fiber include polyamide fiber, fluororesin fiber, and phenolic fiber, but the fiber is not limited to these. If the composition contains too much fiber, the composition will not have a putty-like appearance, which is not preferable. In addition to the binder, fine lead powder, and fibers described above, the putty-like composition according to the present invention can be flame-retardant by containing an appropriate amount of other fillers, such as a flame retardant such as aluminum hydroxide, if necessary. It can also be colored by adding a coloring agent. In addition, the radiation shielding putty-like composition according to the present invention is
Although there are no restrictions on the manufacturing method, it can be obtained, for example, by uniformly kneading the required components using a conventional method such as a kneader or roll. The radiation shielding putty-like composition of the present invention having the above-mentioned composition usually has a softness specified in JIS A5752 in the range of 1 to 25 (1 mm) at room temperature, preferably in the range of 3 to 18. , the density is 4 or more, preferably 6 or more. In the present invention, plasticizers for vinyl chloride resins such as dioctyl phthalate, and compounding agents for other synthetic resins and rubbers can also be contained, as long as the above-mentioned physical properties are satisfied. The radiation shielding putty-like composition according to the present invention contains a high content of fine lead powder with a high density, and has an excellent radiation shielding effect, and has a high radiation shielding effect even though the composition has a high density. It has a putty-like appearance, and thus can be easily applied to voids of any shape that may cause radiation leakage, and is non-hardening, so post-treatment such as curing is not required after application. Furthermore, once applied, it retains its shape for a long period of time, but can be easily removed if necessary. In addition, almost no loss on heating was observed. The present invention will be explained below with reference to Examples, but the present invention is not limited to these Examples in any way. It should be noted that, as described above, it is known that the radiation shielding effect of a composition is generally proportional to its areal density, so the density is only mentioned in the Examples. Example A radiation shielding putty-like composition according to the present invention was prepared by kneading the components shown in the table with a roll. All of these contain large amounts of lead fine powder and metal oxide powder, and as shown in the table, although they are dense compositions, they have moderate softness and good self-shape retention. In addition to having excellent applicability or workability, it also has non-curing properties and is easy to remove after construction. Among the putty properties listed in the table, self-shape retention was evaluated as follows. That is, the ease of kneading the composition by hand to form a cube of approximately 1 cm was evaluated, and the stability of the resulting cube shape was evaluated on a five-point scale. S: It holds together well as a putty, has appropriate softness, and can be easily molded into a cube, and the cube shape is maintained very stably. E: The cohesion as a putty is slightly inferior to that of S, but the moldability into a cube and its stability are also excellent. G: It has a cohesive consistency as a putty, and has sufficient moldability and stability into a cube for practical use. F: It has a certain consistency as a putty and can be formed into a cube, but the cube loses its shape even with the slightest external force. P: The fluidity is excessively high and the putty does not form a cohesive structure, making it difficult to form into a cube. In addition, non-curing property was evaluated as good if the change in softness after leaving the composition at room temperature for one month was within 3.0.
【表】【table】
Claims (1)
とも１種からなり、25℃における粘度が104セン
チストークス以上からJIS K2220−1980による稠
度が100以上のバインダー100重量部について、
350メツシユ篩を93％以上パスする鉛微粉末1300
〜2000重量部と、繊維0.1〜50重量部とを含有し、
且つ、非硬化性であることを特徴とする放射線遮
蔽パテ状組成物。1 Regarding 100 parts by weight of a binder consisting of at least one selected from grease and polybutene and having a viscosity of 104 centistokes or more at 25°C and a consistency of 100 or more according to JIS K2220-1980,
1300 fine lead powder that passes over 93% of the 350 mesh sieve
~2000 parts by weight and 0.1 to 50 parts by weight of fiber,
A radiation shielding putty-like composition characterized in that it is non-curable.
Priority Applications (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP8297283A JPS59208500A (en) | 1983-05-12 | 1983-05-12 | Radiation shield putty composition |
| EP84303164A EP0125889B1 (en) | 1983-05-12 | 1984-05-10 | Radiation shielding putty-like composition |
| DE8484303164T DE3467655D1 (en) | 1983-05-12 | 1984-05-10 | Radiation shielding putty-like composition |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP8297283A JPS59208500A (en) | 1983-05-12 | 1983-05-12 | Radiation shield putty composition |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS59208500A JPS59208500A (en) | 1984-11-26 |
| JPH0223837B2 true JPH0223837B2 (en) | 1990-05-25 |
Family
ID=13789128
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP8297283A Granted JPS59208500A (en) | 1983-05-12 | 1983-05-12 | Radiation shield putty composition |
Country Status (3)
| Country | Link |
|---|---|
| EP (1) | EP0125889B1 (en) |
| JP (1) | JPS59208500A (en) |
| DE (1) | DE3467655D1 (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| RU2208851C2 (en) * | 2000-12-26 | 2003-07-20 | Пензенская государственная архитектурно-строительная академия | Composite for producing radiation shielding materials |
| RU2197760C2 (en) * | 2001-04-25 | 2003-01-27 | Региональная общественная организация - Институт эколого-технологических проблем | Biocide cement mortar |
| NZ517385A (en) * | 2002-02-21 | 2004-10-29 | Fletcher Building Holdings Ltd | Wallboard joint material containing barium sulphate |
| CN108276646B (en) * | 2018-02-06 | 2021-04-06 | 中国船舶重工集团公司第七一九研究所 | Proportioning type composite shielding material with neutron and gamma comprehensive shielding effect and preparation method thereof |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3102024A (en) * | 1958-04-30 | 1963-08-27 | Knapp Mills Inc | Metallic powder composition |
| US3114721A (en) * | 1961-01-23 | 1963-12-17 | Gen Electric | Radiation shielding compositions |
| JPS5942280B2 (en) * | 1977-02-25 | 1984-10-13 | 日本原子力研究所 | radiation shielding material |
| FR2485677B1 (en) * | 1980-06-27 | 1985-09-20 | Poujaud Edouard | FLEXIBLE AND ELASTIC PRODUCT FOR MAKING PROTECTIVE SEALS AND TRIMS |
| FR2485788A1 (en) * | 1980-06-27 | 1981-12-31 | Poujaud Edouard | Radiation absorbing material for mfg. protective screens - where foam made from polymers and boron carbide absorbs neutrons etc. and also functions as fire barrier |
| JPS5826298A (en) * | 1981-08-11 | 1983-02-16 | 昭和電工株式会社 | Neutron shielding material |
| DE3224105A1 (en) * | 1982-06-29 | 1984-01-05 | Nukem Gmbh, 6450 Hanau | Method for shielding against ionising radiation |
-
1983
- 1983-05-12 JP JP8297283A patent/JPS59208500A/en active Granted
-
1984
- 1984-05-10 EP EP84303164A patent/EP0125889B1/en not_active Expired
- 1984-05-10 DE DE8484303164T patent/DE3467655D1/en not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| DE3467655D1 (en) | 1987-12-23 |
| EP0125889B1 (en) | 1987-11-19 |
| JPS59208500A (en) | 1984-11-26 |
| EP0125889A1 (en) | 1984-11-21 |
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