JPH0338639Y2 - - Google Patents
Info
- Publication number
- JPH0338639Y2 JPH0338639Y2 JP1985126004U JP12600485U JPH0338639Y2 JP H0338639 Y2 JPH0338639 Y2 JP H0338639Y2 JP 1985126004 U JP1985126004 U JP 1985126004U JP 12600485 U JP12600485 U JP 12600485U JP H0338639 Y2 JPH0338639 Y2 JP H0338639Y2
- Authority
- JP
- Japan
- Prior art keywords
- furnace
- gas
- heat
- furnace body
- air
- 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
- 238000010438 heat treatment Methods 0.000 claims description 16
- 239000002245 particle Substances 0.000 claims description 9
- 239000007789 gas Substances 0.000 description 33
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 description 9
- 229910001873 dinitrogen Inorganic materials 0.000 description 7
- ATUOYWHBWRKTHZ-UHFFFAOYSA-N Propane Chemical compound CCC ATUOYWHBWRKTHZ-UHFFFAOYSA-N 0.000 description 6
- 238000005255 carburizing Methods 0.000 description 5
- 238000010586 diagram Methods 0.000 description 5
- 238000011282 treatment Methods 0.000 description 5
- QGZKDVFQNNGYKY-UHFFFAOYSA-N Ammonia Chemical compound N QGZKDVFQNNGYKY-UHFFFAOYSA-N 0.000 description 4
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 description 4
- 230000001276 controlling effect Effects 0.000 description 3
- 238000005121 nitriding Methods 0.000 description 3
- 230000003647 oxidation Effects 0.000 description 3
- 238000007254 oxidation reaction Methods 0.000 description 3
- 239000001294 propane Substances 0.000 description 3
- 238000010926 purge Methods 0.000 description 3
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-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
- 229910002092 carbon dioxide Inorganic materials 0.000 description 2
- 239000001569 carbon dioxide Substances 0.000 description 2
- 239000000919 ceramic Substances 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 230000001105 regulatory effect Effects 0.000 description 2
- 229910021529 ammonia Inorganic materials 0.000 description 1
- 238000005256 carbonitriding Methods 0.000 description 1
- 238000001816 cooling Methods 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 230000005611 electricity Effects 0.000 description 1
- 239000003779 heat-resistant material Substances 0.000 description 1
- 229910001026 inconel Inorganic materials 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 229910052757 nitrogen Inorganic materials 0.000 description 1
- 230000003134 recirculating effect Effects 0.000 description 1
- 230000000087 stabilizing effect Effects 0.000 description 1
- 238000011144 upstream manufacturing Methods 0.000 description 1
- 239000002918 waste heat Substances 0.000 description 1
Description
【考案の詳細な説明】
産業上の利用分野
この考案は炉本体より排出された炉気を加圧し
て再び炉本体へ循環させるようにした流動層熱処
理炉に関する。[Detailed Description of the Invention] Industrial Application Field This invention relates to a fluidized bed heat treatment furnace in which furnace air discharged from the furnace body is pressurized and circulated back to the furnace body.
従来の技術
従来この種の流動層熱処理炉としては、第４図
に示すものが特願昭59−53434号などですでに出
願されている。従来の熱処理炉は高温炉ａにより
排出された炉気を低温炉ｂ内の熱交換パイプｃ内
へ流通させて低温炉ｂ内の流動層と熱交換させた
後、フアンｄにより加圧して再び高温炉ａ内へ循
環させる構成で、廃熱、排ガス成分の再利用とと
もに、炉気の安定化が図れる効果がある。BACKGROUND ART Conventionally, as a fluidized bed heat treatment furnace of this type, the one shown in FIG. 4 has already been filed in Japanese Patent Application No. 59-53434. In the conventional heat treatment furnace, the furnace air discharged from the high-temperature furnace a is passed through the heat exchange pipe c in the low-temperature furnace b to exchange heat with the fluidized bed in the low-temperature furnace b. The configuration in which it is circulated into the high-temperature furnace a has the effect of reusing waste heat and exhaust gas components and stabilizing the furnace air.
考案が解決しようとする問題点
しかし従来の熱処理炉では常に高温炉ａと、低
温炉ｂの両方を運転する必要がある。もし高温炉
ａのみを運転した場合、高温の炉気が熱交換され
ないままフアンｄ内に吸引されるため、フアンｄ
が炉気により損傷されるなどの不具合が発生す
る。この考案は上記不具合を改善する目的でなさ
れたものである。Problems to be Solved by the Invention However, in the conventional heat treatment furnace, it is necessary to constantly operate both the high temperature furnace A and the low temperature furnace B. If only high-temperature furnace a is operated, high-temperature furnace air is sucked into fan d without heat exchange, so fan d
Problems such as damage to the furnace air may occur. This invention was made for the purpose of improving the above-mentioned problems.
問題点を解決するための手段及び作用
加熱手段を有する炉本体内に流動粒子よりなる
流動層を収容すると共に、炉本体内の炉気を耐熱
フアンにより炉本体内へ再循環させることによ
り、炉気の安定化と排ガス成分及び顕熱等の再利
用を図つた流動層熱処理炉。Means and action for solving the problem By housing a fluidized bed made of fluidized particles in the furnace body having a heating means and recirculating the furnace air inside the furnace body into the furnace body using a heat-resistant fan, the furnace A fluidized bed heat treatment furnace designed to stabilize air and reuse exhaust gas components and sensible heat.
実施例
この考案の一実施例を図面を参照して詳述す
る。図において１は周囲に加熱室１ａを有する流
動層熱処理炉の炉本体で、内部にアルミナ粒子な
どの流動粒子よりなる流動層２が収容されてい
る。上記炉本体１の上部には開閉自在な炉蓋３が
設けられていて、この炉蓋３を開放することによ
り流動層２内に熱処理すべきワーク４が投入でき
るようになつている。また炉本体１の底部からは
耐熱フアン５より送られた処理ガスや炉気が導入
されている。上記耐熱フアン５は翼車５ａがイン
コネルやセラミツクなどの耐熱材料により形成さ
れていて、電動機６により一定の回転速度で回転
されると共に、上記耐熱フアン５にはこれと並列
に流量調整弁７に接続されていて、この流量調整
弁７により炉本体１へ送られる処理ガスや炉気の
流量が自動調整できるようになつている。Embodiment An embodiment of this invention will be described in detail with reference to the drawings. In the figure, 1 is a furnace body of a fluidized bed heat treatment furnace having a heating chamber 1a around it, and a fluidized bed 2 made of fluidized particles such as alumina particles is housed inside. A furnace lid 3 that can be opened and closed is provided on the upper part of the furnace body 1, and by opening the furnace lid 3, a workpiece 4 to be heat-treated can be introduced into the fluidized bed 2. Furthermore, processing gas and furnace air sent from a heat-resistant fan 5 are introduced from the bottom of the furnace body 1. The heat-resistant fan 5 has a blade wheel 5a made of a heat-resistant material such as Inconel or ceramic, and is rotated by an electric motor 6 at a constant speed. The flow rate adjustment valve 7 is connected to the furnace body 1 so that the flow rate of the processing gas and furnace air sent to the furnace body 1 can be automatically adjusted.
一方炉本体１の底部へ導入された処理ガスや炉
気はガス分散板８により分散されて流動層２内へ
流入し、流動層２の流動粒子を流動させて、流動
層２内のワーク４を熱処理すると共に、流動層２
を通過した処理ガスや炉気は炉蓋３に設けられた
セラミツクよりなるフイルダ９を通過する際、ガ
ス中に混入された流動粒子が除去され、さらに排
気管１０へ排出される。排気管１０へ排出された
炉気は再び耐熱フアン５に吸入されて加圧された
後炉本体１へ再循環されて、炉本体１内の炉気の
安定化を図るようになつている。 On the other hand, the processing gas and furnace air introduced into the bottom of the furnace body 1 are dispersed by the gas distribution plate 8 and flow into the fluidized bed 2, causing the fluidized particles in the fluidized bed 2 to flow, and the workpieces in the fluidized bed 2 to be At the same time, the fluidized bed 2
When the processing gas and furnace air that have passed through pass through a ceramic filter 9 provided on the furnace lid 3, fluidized particles mixed in the gas are removed, and the gas is further discharged to the exhaust pipe 10. Furnace air discharged into the exhaust pipe 10 is sucked into the heat-resistant fan 5 again, pressurized, and then recirculated to the furnace body 1 to stabilize the furnace air within the furnace body 1.
一方、例えばレトルトサイズが400φの炉本体
１に80メツシユのアルミナ粒子を流動粒子として
収容した場合、これら流動粒子を流動させるガス
の流量は第２図に示すようになり、流量層温度の
上昇とともに変化する。すなわち炉内温度を全体
に亘つて一様にするためには、一定体積のガスを
炉内へ供給する必要があり、従つて流動層温度が
上れば、Ｎ（15℃、1ataでの体積）はシヤルル
の法則により小さくなる。そこで常に安定した炉
気を得るために、この考案の実施例では炉本体１
内の温度を熱電対などの温度検出器１１で検出す
ると共に、この温度信号をガス流量制御装置１２
へ送つている。ガス流量制御装置１２では温度検
出器１１から送られた温度信号に応じて制御信号
を流量調整弁７のアクチユエータ７ａへ出力し、
流量調整弁７により炉本体１へ送られるガス流量
を調整することにより、炉本体１内の温度が常に
全体に亘つて一様となるよう制御されている。 On the other hand, if, for example, 80 mesh alumina particles are housed as fluidized particles in the furnace body 1 with a retort size of 400φ, the flow rate of the gas that makes these fluidized particles flow will be as shown in Figure 2, and as the temperature of the flow bed increases, Change. In other words, in order to make the temperature inside the furnace uniform throughout, it is necessary to supply a constant volume of gas into the furnace. ) becomes smaller according to Scharles' law. Therefore, in order to always obtain stable furnace air, in the embodiment of this invention, the furnace main body 1
A temperature sensor 11 such as a thermocouple detects the temperature inside the gas flow controller 12, and this temperature signal is sent to a gas flow rate controller 12.
I am sending it to The gas flow rate control device 12 outputs a control signal to the actuator 7a of the flow rate adjustment valve 7 in response to the temperature signal sent from the temperature detector 11,
By adjusting the flow rate of gas sent to the furnace body 1 by the flow rate regulating valve 7, the temperature inside the furnace body 1 is controlled to be always uniform throughout.
次に作用を説明すると、いまワーク４を無酸化
加熱する場合は炉本体１内の温度を400〜1000℃
に加熱した状態で、管路１５に設けたバルブ１６
を開放して、窒素供給源より窒素ガスを炉本体１
内へ毎分１〜7Nの割合で送り込む。またワー
ク４を投入すべく炉蓋３を開放する場合は、耐熱
フアン５内に空気が吸込まれるのを防止するため
100〜150N／分の窒素ガスを送り込む。窒素ガ
スの供給開始時も同様な目的で100〜150N／分
の窒素ガスを20秒〜１分程度送り込む。その後は
１〜7N／分とし、低温処理の場合は供給量を
増大させる。 Next, to explain the operation, when heating the workpiece 4 without oxidation, the temperature inside the furnace body 1 is set to 400 to 1000℃.
The valve 16 provided in the conduit 15 is heated to
is opened and nitrogen gas is supplied from the nitrogen supply source to the furnace body 1.
Inject at a rate of 1 to 7 N per minute. Also, when opening the furnace lid 3 to load the workpiece 4, to prevent air from being sucked into the heat-resistant fan 5.
Inject nitrogen gas at 100-150N/min. When starting the supply of nitrogen gas, nitrogen gas is fed at a rate of 100 to 150 N/min for about 20 seconds to 1 minute for the same purpose. Thereafter, the feed rate is 1 to 7 N/min, and the feed rate is increased in the case of low temperature treatment.
以上は無酸化加熱の場合であるが、窒化処理す
る場合は、炉本体１内の温度を450〜700℃に昇温
した状態で、上記の無酸化加熱の場合と同様に窒
素ガスを供給して炉本体１内や循環経路内の空気
を排除（パージ）しながら管路１９に設けたバル
ブ２０を開放して、アンモニア供給源より炉本体
１へアンモニアガスを５〜30N／分供給する。 The above is a case of non-oxidation heating, but when performing nitriding treatment, nitrogen gas is supplied in the same way as in the case of non-oxidation heating with the temperature inside the furnace body 1 raised to 450 to 700°C. While purging the air inside the furnace body 1 and the circulation path, the valve 20 provided in the pipe line 19 is opened, and ammonia gas is supplied from the ammonia supply source to the furnace body 1 at a rate of 5 to 30 N/min.
また軟窒化処理の場合は、上記操作と同時に管
路２１のバルブ２２を開放して炭酸ガス供給源よ
り炭酸ガスを0.5〜3N／分を約１分間供給す
る。 In the case of soft nitriding treatment, the valve 22 of the conduit 21 is opened at the same time as the above operation, and carbon dioxide gas is supplied from the carbon dioxide gas supply source at a rate of 0.5 to 3 N/min for about 1 minute.
そして酸窒化処理の場合は、管路１３のバルブ
１４を開放して0.5〜3N／分の空気を供給す
る。 In the case of oxynitriding treatment, the valve 14 of the conduit 13 is opened to supply air for 0.5 to 3 N/min.
一方浸炭処理の場合は、窒素ガスを供給して空
気をパージした後管路２３のバルブ２４を開放し
てアルコール供給源よりアルコールを２〜20／
時供給し、さらに管路１７のバルブ１８を開放し
てプロパンガス供給源よりプロパンガスを０〜
3N／分程度供給する。このときプロパンガス
の流量を調整することにより、炉本体１内の浸炭
雰囲気を変化させることができると共に、浸炭ガ
ス雰囲気を自動制御するためには、炉本体１内の
ガスを赤外線ガス分析計やO2センサなどの炉内
ガス検出器２５により検出してガス雰囲気制御装
置２６へ送り、さらに制御装置２６の出力により
バルブ１８や絞り１８ａを開閉制御することによ
り、炉本体１内の浸炭ガス雰囲気が設定値となる
ように制御すればよい。 On the other hand, in the case of carburizing treatment, after purging the air by supplying nitrogen gas, the valve 24 of the pipe line 23 is opened, and 2 to 20% of alcohol is supplied from the alcohol supply source.
Then, open the valve 18 of the pipe line 17 to supply propane gas from the propane gas supply source to 0~
Supply approximately 3N/min. At this time, by adjusting the flow rate of propane gas, the carburizing atmosphere inside the furnace body 1 can be changed, and in order to automatically control the carburizing gas atmosphere, the gas inside the furnace body 1 can be measured using an infrared gas analyzer or an infrared gas analyzer. The carburizing gas atmosphere inside the furnace body 1 is detected by an in-furnace gas detector 25 such as an O 2 sensor and sent to the gas atmosphere control device 26, and the output of the control device 26 controls the opening and closing of the valve 18 and throttle 18a. It is only necessary to control so that the value becomes the set value.
浸炭窒化の場合は、さらにバルブ２０を開放し
て１〜5N／分のアンモニアガスを供給する。 In the case of carbonitriding, the valve 20 is further opened to supply ammonia gas at a rate of 1 to 5 N/min.
なお上記実施例において耐熱フアン５の能力
は、排出ガス流量1000N／分、排気圧1000mm／
Ag〜3000mm／Agである。 In the above embodiment, the capacity of the heat-resistant fan 5 is as follows: exhaust gas flow rate: 1000N/min, exhaust pressure: 1000mm/min.
Ag~3000mm/Ag.
また耐熱フアン５を駆動する電動機６の回転を
制御することにより耐熱フアンの流量制御を行つ
てもよく、さらに耐熱フアン５は第３図に示すよ
うに高圧空気により回転されるタービン２７によ
り駆動してもよい。この場合耐熱フアン５の流量
制御は、ガス流量制御装置１２より出力される制
御信号によりタービン２７の上流に設けられた流
量調整弁７のアクチユエータ７ａを制御すること
により行うもので、耐熱フアン５の駆動源の回転
を制御する場合に比べて周波数変換器などを必要
としないため、安価に実施することができる。 Further, the flow rate of the heat-resistant fan 5 may be controlled by controlling the rotation of the electric motor 6 that drives the heat-resistant fan 5. Furthermore, the heat-resistant fan 5 is driven by a turbine 27 rotated by high-pressure air as shown in FIG. You can. In this case, the flow rate control of the heat-resistant fan 5 is performed by controlling the actuator 7a of the flow rate regulating valve 7 provided upstream of the turbine 27 using a control signal output from the gas flow rate control device 12. Compared to controlling the rotation of the drive source, this method does not require a frequency converter, so it can be implemented at low cost.
考案の効果
この考案は以上詳述したように、炉本体内の炉
気を耐熱フアンを用いて炉本体内へ循環させ炉気
の安定化を図るようにしたもので、炉気を熱交換
させた後炉本体へ循環させる必要がないため、従
来のように低温炉と同時に運転する必要がない。
また排ガス中の成分や顕熱が再利用できると共
に、炉気を循環させない熱処理炉に比べて空気パ
ージに使用する窒素ガスの使用用が1/30〜1/10
に、また加熱に使用する電力量やガス量が3/4〜
２／３となり、非常に経済的である。Effects of the device As detailed above, this device uses a heat-resistant fan to circulate the furnace air inside the furnace body to stabilize the furnace air. Since there is no need to circulate it back to the furnace body after cooling, there is no need to operate it at the same time as the low-temperature furnace as in the past.
In addition, the components and sensible heat in the exhaust gas can be reused, and the amount of nitrogen gas used for air purge is 1/30 to 1/10 that of heat treatment furnaces that do not circulate furnace air.
In addition, the amount of electricity and gas used for heating is reduced by 3/4~
It is 2/3, which is very economical.
また上記耐熱フアンに並列に流量調整弁を接続
して、この流量調整弁により炉本体内へ流入する
処理ガスや炉気の流量を調整できるようにしたこ
とから、炉本体内の流動層の安定した流動が可能
となり、これによつて窒化処理や浸炭処理などの
熱処理の安定化が図れるようになるため、品質の
良好な熱処理品が得られるようになる。 In addition, a flow rate adjustment valve is connected in parallel to the heat-resistant fan, and the flow rate of the processing gas and furnace air flowing into the furnace body can be adjusted by this flow rate adjustment valve, which stabilizes the fluidized bed inside the furnace body. This makes it possible to stabilize heat treatments such as nitriding and carburizing, thereby making it possible to obtain heat-treated products of good quality.
図面はこの考案の一実施例を示し、第１図は全
体的な構成図、第２図は炉本体内の温度と流動ガ
ス量の関係を示す線図、第３図は耐熱フアン駆動
部の別の実施例を示す説明図、第４図は従来の説
明図である。
１は炉本体、２は流動層、５は耐熱フアン。
The drawings show one embodiment of this invention; Fig. 1 is an overall configuration diagram, Fig. 2 is a diagram showing the relationship between the temperature inside the furnace body and the amount of flowing gas, and Fig. 3 is a diagram showing the heat-resistant fan drive section. An explanatory diagram showing another embodiment, FIG. 4 is a conventional explanatory diagram. 1 is the furnace body, 2 is the fluidized bed, and 5 is the heat-resistant fan.
Claims (1)
る流動層２を収容し、かつ上記炉本体１内の炉気
を耐熱フアン５により炉本体１内に再循環させる
と共に、上記耐熱フアン５と並列に、処理ガスや
炉気の流量を調整する流量調整弁７を接続してな
る流動層熱処理炉。 A fluidized bed 2 made of fluidized particles is housed in a furnace body 1 having a heating means, and the furnace air in the furnace body 1 is recirculated into the furnace body 1 by a heat-resistant fan 5, which is parallel to the heat-resistant fan 5. A fluidized bed heat treatment furnace is constructed by connecting a flow rate adjustment valve 7 for adjusting the flow rate of processing gas and furnace air.
Priority Applications (4)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1985126004U JPH0338639Y2 (en) | 1985-08-20 | 1985-08-20 | |
| US06/896,783 US4730811A (en) | 1985-08-20 | 1986-08-15 | Heat treatment apparatus with a fluidized-bed furnace |
| DE3627941A DE3627941C2 (en) | 1985-08-20 | 1986-08-18 | Heat treatment device with a fluidized bed furnace |
| GB8620216A GB2179267B (en) | 1985-08-20 | 1986-08-20 | Heat treatment apparatus |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1985126004U JPH0338639Y2 (en) | 1985-08-20 | 1985-08-20 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS62105495U JPS62105495U (en) | 1987-07-06 |
| JPH0338639Y2 true JPH0338639Y2 (en) | 1991-08-14 |
Family
ID=31019403
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1985126004U Expired JPH0338639Y2 (en) | 1985-08-20 | 1985-08-20 |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0338639Y2 (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP5582792B2 (en) * | 2010-01-19 | 2014-09-03 | 株式会社 タニキカン | Heating device |
| JP2011149559A (en) * | 2010-01-19 | 2011-08-04 | Tani Kikan Kogyo Kk | Heating device |
Family Cites Families (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5675510U (en) * | 1979-11-12 | 1981-06-20 | ||
| JPS56112412U (en) * | 1980-01-25 | 1981-08-31 |
-
1985
- 1985-08-20 JP JP1985126004U patent/JPH0338639Y2/ja not_active Expired
Also Published As
| Publication number | Publication date |
|---|---|
| JPS62105495U (en) | 1987-07-06 |
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