JPH0136239B2 - - Google Patents
Info
- Publication number
- JPH0136239B2 JPH0136239B2 JP56086101A JP8610181A JPH0136239B2 JP H0136239 B2 JPH0136239 B2 JP H0136239B2 JP 56086101 A JP56086101 A JP 56086101A JP 8610181 A JP8610181 A JP 8610181A JP H0136239 B2 JPH0136239 B2 JP H0136239B2
- Authority
- JP
- Japan
- Prior art keywords
- sheathed heater
- heating wire
- cao
- powder
- metal pipe
- 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
Links
- 239000000843 powder Substances 0.000 claims description 28
- 238000010438 heat treatment Methods 0.000 claims description 18
- 229910052751 metal Inorganic materials 0.000 claims description 14
- 239000002184 metal Substances 0.000 claims description 14
- 239000000463 material Substances 0.000 claims description 10
- 229910004298 SiO 2 Inorganic materials 0.000 claims description 9
- 238000001035 drying Methods 0.000 claims description 6
- 229910021193 La 2 O 3 Inorganic materials 0.000 claims description 4
- CPLXHLVBOLITMK-UHFFFAOYSA-N Magnesium oxide Chemical compound [Mg]=O CPLXHLVBOLITMK-UHFFFAOYSA-N 0.000 description 14
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 11
- 150000001875 compounds Chemical class 0.000 description 10
- 238000009413 insulation Methods 0.000 description 10
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 description 8
- 239000000395 magnesium oxide Substances 0.000 description 7
- 239000002274 desiccant Substances 0.000 description 6
- 229910052681 coesite Inorganic materials 0.000 description 4
- 230000000052 comparative effect Effects 0.000 description 4
- 229910052906 cristobalite Inorganic materials 0.000 description 4
- 238000010292 electrical insulation Methods 0.000 description 4
- 239000011521 glass Substances 0.000 description 4
- 239000000377 silicon dioxide Substances 0.000 description 4
- 235000012239 silicon dioxide Nutrition 0.000 description 4
- 229910052682 stishovite Inorganic materials 0.000 description 4
- 229910052905 tridymite Inorganic materials 0.000 description 4
- 239000013078 crystal Substances 0.000 description 3
- 229920002050 silicone resin Polymers 0.000 description 3
- BHPQYMZQTOCNFJ-UHFFFAOYSA-N Calcium cation Chemical compound [Ca+2] BHPQYMZQTOCNFJ-UHFFFAOYSA-N 0.000 description 2
- PNEYBMLMFCGWSK-UHFFFAOYSA-N aluminium oxide Inorganic materials [O-2].[O-2].[O-2].[Al+3].[Al+3] PNEYBMLMFCGWSK-UHFFFAOYSA-N 0.000 description 2
- 229910001424 calcium ion Inorganic materials 0.000 description 2
- 238000006243 chemical reaction Methods 0.000 description 2
- 239000002131 composite material Substances 0.000 description 2
- 230000006866 deterioration Effects 0.000 description 2
- 229920006015 heat resistant resin Polymers 0.000 description 2
- 229910001120 nichrome Inorganic materials 0.000 description 2
- 230000001681 protective effect Effects 0.000 description 2
- 238000005979 thermal decomposition reaction Methods 0.000 description 2
- 229910018072 Al 2 O 3 Inorganic materials 0.000 description 1
- WGLPBDUCMAPZCE-UHFFFAOYSA-N Trioxochromium Chemical compound O=[Cr](=O)=O WGLPBDUCMAPZCE-UHFFFAOYSA-N 0.000 description 1
- DCCZSRCUYILDJV-UHFFFAOYSA-N [O-2].[Cr+3].[O-2].[Ca+2] Chemical compound [O-2].[Cr+3].[O-2].[Ca+2] DCCZSRCUYILDJV-UHFFFAOYSA-N 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 229910000423 chromium oxide Inorganic materials 0.000 description 1
- 229910052593 corundum Inorganic materials 0.000 description 1
- 230000007423 decrease Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000005350 fused silica glass Substances 0.000 description 1
- 229910001293 incoloy Inorganic materials 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 239000011148 porous material Substances 0.000 description 1
- 238000007789 sealing Methods 0.000 description 1
- 238000004804 winding Methods 0.000 description 1
- 229910001845 yogo sapphire Inorganic materials 0.000 description 1
Landscapes
- Resistance Heating (AREA)
Description
本発明は、シーズヒータに関し、特に高温多湿
雰囲気中に放置されても絶縁抵抗値が劣化しにく
く、かつ寿命の長いシーズヒータを提供しようと
するものである。
一般にシーズヒータは第１図に示すように両端
に端子棒１を備えた電熱線２を金属パイプ３に挿
入し、この金属パイプ３にマグネシア等の電気絶
縁粉末４を充填してなり、必要に応じて金属パイ
プ３の両端を耐熱性樹脂５やガラスで封口してな
るものである。
マグネシア等の電気絶縁粉末４は吸湿性を有す
るため、シーズヒータを多湿雰囲気中に放置する
と絶縁抵抗値が低下する。このため、電気絶縁粉
末４にシリコーン樹脂を添加したり、金属パイプ
３の両端をガラスで完全封口することが提案され
ていた。しかし、シリコーン樹脂を添加した電気
絶縁粉末４を用いると、シリコーン樹脂の耐熱温
度が450℃程度であるため500℃以上の高温では使
用できないという欠点があつた。一方、ガラスで
完全封口したシーズヒータは端子棒１に外力が加
わるとガラスにクラツクが生じ、封止効果がなく
なりシーズヒータの絶縁抵抗値が低下するという
欠点を有していた。
このため、本発明者らは、電気絶縁粉末とし
て、CaOとSiO2とを主成分とする無機質乾燥材
を添加することにより、高温多湿雰囲気中に放置
しても、絶縁抵抗値の劣化しにくいシーズヒータ
を得ることができるという結論を得ている。
しかし、このシーズヒータは、金属パイプ表面
温度650℃以上の高温で使用すると、短時間で電
熱線２が断線してしまうという欠点があつた。
例えば電熱線２としてニクロム線が使用される
と、シーズヒータ内のわずかな酸素により電熱線
表面に不連続または非常に薄い酸化クロム被膜が
形成されるが、この酸化クロム被膜と無機質乾燥
材中のカルシウムイオンが反応し、多孔質な酸化
カルシウム−酸化クロム複合化合物を形成すると
ともにカルシウムイオンがこの複合化合物の孔を
通つて電熱線内部にまで拡散し、電熱線２を著し
く細くして、終局的には断線させ、寿命を短くす
ると想定される。
本発明は、上記従来の欠点を解消し、所期の目
的を達成するシーズヒータを提供するものであ
る。
本発明者らは、電気絶縁粉末について各種検討
した結果、NiO、CoO、WO3、Nb2O5、Y2O3、
CeO2、La2O3の群から選ばれる少くとも一種の
酸化物と、CaOおよびSiO2を主成分とする無機
質乾燥材とを添加した電気絶縁粉末を用いること
により、高温多湿雰囲気中に放置されても絶縁抵
抗値が劣化しにくく、かつ寿命の長いシーズヒー
タを得ることができるという結論を得た。
これは、上記電気絶縁粉末を使用すると、製造
工程中または使用初期の段階で、電熱線と、上記
酸化物とが反応し、電熱線表面に、緻密で安定な
保護被膜が形成され、この結果、従来見られた電
熱線２と無機質乾燥材成分との反応が抑制され、
寿命が長くなるためであると想定される。
一方、CaOおよびSiO2を主成分とするCaO−
SiO2系化合物、CaO−Al2O3−SiO2系化合物、
CaO−MgO−SiO2系化合物等の無機質乾燥材は、
100℃以下の低温度域において、シーズヒータ内
部に侵入してきた湿気あるいは水分を結晶水また
は結合水の形で強固に吸収し、一方、200℃以上
の高温度域においては、その結晶水または結合水
を加熱分解により、広い温度範囲にまたがつて
徐々に遊離し、その遊離水分をシーズヒータ外部
に放出する機能を具備するものであり、かつこの
ような機能が常温〜1000℃の温度サイクルにおい
て可逆的、安定的に行なわれるために、高温多湿
雰囲気中に放置されても、シーズヒータの絶縁抵
抗値の劣化は抑制される。
以下、本発明の具体的な実施例について説明す
る。
CaOとSiO2とをモル比で３：２に配合し、そ
の混合物を1200℃の温度で２時間反応させ、CaO
−SiO2系化合物からなる無機質乾燥材を作成し
た。
電気絶縁粉末の主成分として、電融マグネシア
粉末を使用した。
この電融マグネシア粉末に、上記無機質乾燥材
と、NiOをそれぞれ重量比で10％および１％添加
し、均一に混合し、電気絶縁粉末４を準備した。
また、電熱線２として線径0.29mmのニクロム線
第１種を用い、これを巻径２mmのコイル状とし、
両端に端子棒１を接続した。
さらに、金属パイプ３として長さ413mm、外径
８mm、肉厚0.46mmのNCF2P（商品名インコロイ
800）を用いた。
この金属パイプ３に上記端子棒１を両端に接続
した電熱線２を挿入し、この金属パイプ３にあら
かじめ準備しておいた上記電気絶縁粉末４を充填
し、圧延減径、焼鈍（1050℃、10分間）の各工程
を経て、金属パイプ３を長さ500mm、外径6.6mmと
し、さらに金属パイプ３の両端を耐熱性樹脂５で
簡易封口してシーズヒータを完成した。
なお、比較のために、従来例として、電融マグ
ネシア粉末のみの電気絶縁粉末４を使用した場
合、さらに比較例として、上記CaO−SiO2系化
合物からなる無機質乾燥機を添加した電融マグネ
シア粉末を電気絶縁粉末４として使用した場合に
ついて、それぞれ、同様にしてシーズヒータを完
成した。
完成したそれぞれのシーズヒータを、40℃、相
対湿度95％の高温多湿雰囲気中に投入し、室温で
の絶縁抵抗値の経時変化を測定した。この結果を
第２図に示した。第２図において、ａは実施例、
ｂは従来例、ｃは比較例を示す。
また、パイプ表面温度が800℃になるように調
整し、20分on−10分offのサイクルテストによる
寿命試験を行い、電熱線２が断線するまでのサイ
クル（寿命）を調べた。
この結果を第１表に示す。
The present invention relates to a sheathed heater, and particularly aims to provide a sheathed heater whose insulation resistance value does not easily deteriorate even when left in a high temperature and humidity atmosphere, and which has a long life. Generally, a sheathed heater is made by inserting a heating wire 2 with terminal rods 1 at both ends into a metal pipe 3, as shown in Fig. 1, and filling this metal pipe 3 with an electrically insulating powder 4 such as magnesia. Accordingly, both ends of the metal pipe 3 are sealed with heat-resistant resin 5 or glass. Since the electrical insulating powder 4 such as magnesia has hygroscopicity, the insulation resistance value decreases when the sheathed heater is left in a humid atmosphere. For this reason, it has been proposed to add silicone resin to the electrically insulating powder 4 or to completely seal both ends of the metal pipe 3 with glass. However, when the electrical insulation powder 4 containing silicone resin is used, there is a drawback that it cannot be used at high temperatures of 500°C or higher because the silicone resin has a heat resistance temperature of about 450°C. On the other hand, a sheathed heater that is completely sealed with glass has the disadvantage that when external force is applied to the terminal bar 1, cracks occur in the glass, which loses the sealing effect and reduces the insulation resistance of the sheathed heater. For this reason, the present inventors added an inorganic desiccant material containing CaO and SiO 2 as main components to the electrical insulating powder so that the insulation resistance value would be less likely to deteriorate even if left in a high temperature and humid atmosphere. It has been concluded that a sheathed heater can be obtained. However, this sheathed heater has a drawback that when used at a high temperature of 650° C. or higher on the surface of the metal pipe, the heating wire 2 breaks in a short period of time. For example, when a nichrome wire is used as the heating wire 2, a discontinuous or very thin chromium oxide film is formed on the surface of the heating wire due to a small amount of oxygen in the sheathed heater. The calcium ions react to form a porous calcium oxide-chromium oxide composite compound, and at the same time, the calcium ions diffuse into the heating wire through the pores of this composite compound, making the heating wire 2 significantly thinner and ultimately It is assumed that this will cause wire breakage and shorten the lifespan. The present invention provides a sheathed heater that eliminates the above-mentioned conventional drawbacks and achieves the intended purpose. As a result of various studies on electrical insulating powders, the present inventors found that NiO, CoO, WO 3 , Nb 2 O 5 , Y 2 O 3 ,
By using an electrical insulating powder containing at least one kind of oxide selected from the group of CeO 2 and La 2 O 3 and an inorganic desiccant material mainly composed of CaO and SiO 2 , it is possible to leave the product in a high temperature and humid atmosphere. It was concluded that it is possible to obtain a sheathed heater that has a long lifespan and whose insulation resistance value does not easily deteriorate even when exposed to heat. This is because when the above electric insulating powder is used, the heating wire reacts with the above oxide during the manufacturing process or at the initial stage of use, forming a dense and stable protective film on the surface of the heating wire. , the reaction between the heating wire 2 and the inorganic desiccant component that was conventionally observed is suppressed,
It is assumed that this is because the lifespan becomes longer. On the other hand, CaO− whose main components are CaO and SiO2
SiO2 - based compounds, CaO- Al2O3 - SiO2- based compounds,
Inorganic drying materials such as CaO−MgO−SiO 2- based compounds are
In the low temperature range of 100℃ or less, moisture or water that has entered the sheathed heater is strongly absorbed in the form of crystal water or bound water, while in the high temperature range of 200℃ or higher, the crystal water or water It has the function of gradually liberating water over a wide temperature range through thermal decomposition and releasing the liberated moisture to the outside of the sheathed heater. Since this is performed reversibly and stably, deterioration of the insulation resistance value of the sheathed heater is suppressed even if it is left in a high temperature and humid atmosphere. Hereinafter, specific examples of the present invention will be described. CaO and SiO 2 were mixed in a molar ratio of 3:2, and the mixture was reacted at a temperature of 1200°C for 2 hours to form CaO
-An inorganic drying material made of SiO 2- based compound was created. Electrofused magnesia powder was used as the main component of the electrical insulating powder. To this electrofused magnesia powder, the above-mentioned inorganic drying material and NiO were added in a weight ratio of 10% and 1%, respectively, and mixed uniformly to prepare electrical insulation powder 4. In addition, a first type nichrome wire with a wire diameter of 0.29 mm was used as the heating wire 2, and this was made into a coil shape with a winding diameter of 2 mm.
Terminal bar 1 was connected to both ends. Furthermore, as the metal pipe 3, NCF2P (product name Incoloy) with length 413 mm, outer diameter 8 mm, wall thickness 0.46 mm
800) was used. The heating wire 2 with the terminal rod 1 connected to both ends is inserted into the metal pipe 3, the metal pipe 3 is filled with the electrical insulation powder 4 prepared in advance, and the metal pipe 3 is reduced in diameter and annealed (1050°C, After completing each step (10 minutes), the metal pipe 3 was made to have a length of 500 mm and an outer diameter of 6.6 mm, and both ends of the metal pipe 3 were simply sealed with heat-resistant resin 5 to complete a sheathed heater. For comparison, as a conventional example, electric insulating powder 4 containing only electrofused magnesia powder was used, and as a comparative example, electrofused magnesia powder to which an inorganic dryer made of the CaO-SiO 2 type compound was added was used. Sheathed heaters were completed in the same manner using each as the electrical insulating powder 4. Each completed sheathed heater was placed in a high-temperature and humid atmosphere of 40°C and 95% relative humidity, and changes in insulation resistance over time at room temperature were measured. The results are shown in FIG. In FIG. 2, a is an example,
b indicates a conventional example, and c indicates a comparative example. In addition, the pipe surface temperature was adjusted to 800° C., and a life test was conducted using a cycle test of 20 minutes on and 10 minutes off, and the cycle (life) until the heating wire 2 broke was investigated. The results are shown in Table 1.
【表】
第１表および第２図から明らかなように、実施
例のシーズヒータは、高温多湿雰囲気中に放置し
ても、絶縁抵抗値が劣化しにくく、比較例のシー
ズヒータと比較して、寿命は長くなつた。
このように、NiOは、CaOおよびSiO2を主成
分とする無機質乾燥材を添加した電融マグネシア
粉末を電気絶縁粉末として用いたシーズヒータの
寿命を長くすることが明らかとなつた。
なお、添加する酸化物として、実施例で示した
NiO以外に、CoO、Nb2O5、WO3、Y2O3、
CeO2、La2O3から選ばれる酸化物であつても同
様の傾向を示した。
また、無機質乾燥材として、実施例で示した
CaO−SiO2系化合物に代えて、CaO−Al2O3−
SiO2系化合物、CaO−MgO−SiO2系化合物でも
よく、電気絶縁粉末の主成分として、電融アルミ
ナ粉末、電融シリカ粉末でもよい。
以上の説明から明らかなように本発明によれ
ば、金属パイプに電熱線を挿入するとともに電気
絶縁粉末を充填してなるシーズヒータにおいて、
前記電気絶縁粉末として、CaOとSiO2を主成分
とする無機質乾燥材と、CoO、WO3、Nb2O5、
Y2O3、CeO2、La2O3の群から選ばれる少くとも
一種の酸化物とを添加したものを用いるようにし
たもので、このような電気絶縁粉末を用いること
により、製造工程中または使用初期の段階で、電
熱線と前記酸化物とが反応し、電熱線表面に緻密
で安定な保護被膜が形成されるため、従来見られ
た電熱線と無機質乾燥材成分との反応を抑制する
ことができ、これにより、長寿命化がはかれる。
一方、CaOとSiO2を主成分とする無機質乾燥材
は、100℃以下の低温度域においては、シーズヒ
ータ内部に侵入してきた湿気あるいは水分を結晶
水または結合水の形で強固に吸収し、また200℃
以上の高温度域においては、その結晶水または結
合水を加熱分解により、広い温度範囲にまたがつ
て徐々に遊離し、その遊離水分をシーズヒータの
外部に放出する機能を具備し、かつこのような機
能が常温〜1000℃の温度サイクルにおいて可逆
的、安定的に行なわれるため、高温多湿雰囲気中
に放置されても、シーズヒータの絶縁抵抗値の劣
化は抑制され、その結果、寿命の長いシーズヒー
タを提供することができるものである。[Table] As is clear from Table 1 and Figure 2, the insulation resistance value of the sheathed heater of the example is less likely to deteriorate even when left in a high temperature and humid atmosphere, compared to the sheathed heater of the comparative example. , life expectancy has become longer. In this way, it has been revealed that NiO extends the life of a sheathed heater using fused magnesia powder as an electrical insulating powder to which an inorganic desiccant material mainly composed of CaO and SiO 2 is added. In addition, as the oxide to be added, the
In addition to NiO, CoO, Nb 2 O 5 , WO 3 , Y 2 O 3 ,
A similar tendency was observed even with oxides selected from CeO 2 and La 2 O 3 . In addition, as an inorganic drying material,
CaO−Al 2 O 3 − instead of CaO−SiO 2 based compound
It may be a SiO2 - based compound or a CaO-MgO- SiO2 -based compound, or it may be a fused alumina powder or fused silica powder as the main component of the electrical insulating powder. As is clear from the above description, according to the present invention, in a sheathed heater formed by inserting a heating wire into a metal pipe and filling it with electrical insulating powder,
As the electrical insulating powder, an inorganic drying material containing CaO and SiO 2 as main components, CoO, WO 3 , Nb 2 O 5 ,
At least one oxide selected from the group of Y 2 O 3 , CeO 2 , and La 2 O 3 is added. By using such electrical insulating powder, Or, at the initial stage of use, the heating wire and the oxide react, forming a dense and stable protective film on the surface of the heating wire, suppressing the reaction between the heating wire and the inorganic desiccant component that was previously observed. This allows for longer life.
On the other hand, inorganic desiccant materials mainly composed of CaO and SiO 2 strongly absorb moisture or moisture that has entered the sheathed heater in the form of crystallized water or bound water at low temperatures below 100°C. Also 200℃
In the above high temperature range, the crystal water or bound water is gradually released over a wide temperature range by thermal decomposition, and the released water is released to the outside of the sheathed heater. This function is performed reversibly and stably in a temperature cycle from room temperature to 1000℃, so even if the sheathed heater is left in a high-temperature and humid atmosphere, the deterioration of the insulation resistance value of the sheathed heater is suppressed, resulting in a long-life sheathed heater. It can provide a heater.
第１図は一般的なシーズヒータの断面図、第２
図は本発明の実施例および従来例、比較例のシー
ズヒータにおける高温多湿雰囲気中に放置した時
の室温での絶縁抵抗値の経時変化を示す特性図で
ある。
２……電熱線、３……金属パイプ、４……電気
絶縁粉末。
Figure 1 is a cross-sectional view of a typical sheathed heater, Figure 2
The figure is a characteristic diagram showing changes over time in insulation resistance values at room temperature in sheathed heaters of examples of the present invention, conventional examples, and comparative examples when left in a high-temperature and humid atmosphere. 2... Heating wire, 3... Metal pipe, 4... Electrical insulation powder.
Claims (1)
絶縁粉末を充填してなるシーズヒータにおいて、
前記電気絶縁粉末としてCaOとSiO2を主成分と
する無機質乾燥材と、NiO、CoO、WO3、
Nb2O5、Y2O3、CeO2、La2O3の群から選ばれる
少くとも一種の酸化物とを添加したものを用いて
なるシーズヒータ。1 In a sheathed heater made by inserting a heating wire into a metal pipe and filling it with electrical insulating powder,
The electrical insulating powder is an inorganic drying material containing CaO and SiO 2 as main components, NiO, CoO, WO 3 ,
A sheathed heater containing at least one kind of oxide selected from the group of Nb 2 O 5 , Y 2 O 3 , CeO 2 and La 2 O 3 .
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP8610181A JPS57202083A (en) | 1981-06-03 | 1981-06-03 | Sheathed heater |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP8610181A JPS57202083A (en) | 1981-06-03 | 1981-06-03 | Sheathed heater |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS57202083A JPS57202083A (en) | 1982-12-10 |
| JPH0136239B2 true JPH0136239B2 (en) | 1989-07-28 |
Family
ID=13877311
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP8610181A Granted JPS57202083A (en) | 1981-06-03 | 1981-06-03 | Sheathed heater |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS57202083A (en) |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5478540A (en) * | 1977-12-06 | 1979-06-22 | Matsushita Electric Ind Co Ltd | Sheathed heater and making method thereof |
| JPS5590095A (en) * | 1978-12-28 | 1980-07-08 | Matsushita Electric Ind Co Ltd | Sheathed heater and method of fabricating same |
-
1981
- 1981-06-03 JP JP8610181A patent/JPS57202083A/en active Granted
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5478540A (en) * | 1977-12-06 | 1979-06-22 | Matsushita Electric Ind Co Ltd | Sheathed heater and making method thereof |
| JPS5590095A (en) * | 1978-12-28 | 1980-07-08 | Matsushita Electric Ind Co Ltd | Sheathed heater and method of fabricating same |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS57202083A (en) | 1982-12-10 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| US3959764A (en) | Gas analyzing element | |
| JPH0136239B2 (en) | ||
| JPS6021448B2 (en) | Electrical insulating material for burying metal heater wires and method for manufacturing the same | |
| US3425121A (en) | Method of making high-temperature encapsulated apparatus | |
| JPS587315Y2 (en) | High temperature thermistor type temperature sensor | |
| JPH0313714B2 (en) | ||
| JPH0138360B2 (en) | ||
| JPS6322642Y2 (en) | ||
| JPS6215998B2 (en) | ||
| JPH038075B2 (en) | ||
| JPS5921517Y2 (en) | Sea heater | |
| JPS6157674B2 (en) | ||
| JPS5951119B2 (en) | Metal pipe for sheathed heater and its manufacturing method | |
| CN1017647B (en) | Process of temp. sensing element made of ceramic platium resistance | |
| JPS6127871B2 (en) | ||
| JPS5914289A (en) | Sheathed heater | |
| JPS5953644B2 (en) | electrical insulation materials | |
| JPS6325472B2 (en) | ||
| JPS6015111B2 (en) | Sea heater | |
| JPS6134233B2 (en) | ||
| JPH0136240B2 (en) | ||
| JPS649716B2 (en) | ||
| JPH0148625B2 (en) | ||
| JPS59175585A (en) | Electrically insulating filling material of high temperaturesheathed heater | |
| JPS6037597B2 (en) | Sea heater |