JPS60215717A - Method for controlling furnace atmosphere in bright heat treatment - Google Patents

Method for controlling furnace atmosphere in bright heat treatment

Info

Publication number
JPS60215717A
JPS60215717A JP6839884A JP6839884A JPS60215717A JP S60215717 A JPS60215717 A JP S60215717A JP 6839884 A JP6839884 A JP 6839884A JP 6839884 A JP6839884 A JP 6839884A JP S60215717 A JPS60215717 A JP S60215717A
Authority
JP
Japan
Prior art keywords
gas
heating chamber
heat treatment
furnace
detected
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.)
Pending
Application number
JP6839884A
Other languages
Japanese (ja)
Inventor
Hitoshi Kabasawa
均 椛澤
Akira Yokoyama
明 横山
Kazuhiro Furuya
古谷　和啓
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Oriental Engineering Co Ltd
Toyota Motor Corp
Original Assignee
Oriental Engineering Co Ltd
Toyota Motor Corp
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by Oriental Engineering Co Ltd, Toyota Motor Corp filed Critical Oriental Engineering Co Ltd
Priority to JP6839884A priority Critical patent/JPS60215717A/en
Publication of JPS60215717A publication Critical patent/JPS60215717A/en
Pending legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
    • C21D1/74—Methods of treatment in inert gas, controlled atmosphere, vacuum or pulverulent material
    • C21D1/76—Adjusting the composition of the atmosphere

Abstract

PURPOSE:To control furnace atmosphere to the conditions optimum for a bright heat treatment by detecting the partial pressure of the remaining oxygen in a heating chamber, introducing a gas for adjusting the atmopshere, etc. therein according to the difference from a set value and controlling the amt. of the remaining oxygen, etc. CONSTITUTION:The partial pressure of the remaining oxygen in the heating chamber of a heat treating furnace is detected and gaseous hydrocarbon, reducing gas or liquid to generate said gas is introduced into the heating chamber when the detected value is higher than a set value. An oxidizing gas or liquid to generate said gas is introduced into the heating chamber to control the amt. of the remaining oxygen when the detected value is lower than the set value. The partial pressure of the remaining carbon monoxide in the heating chamber is detected and a neutral gas is passed in the heating chamber to control the amt. of the remaining carbon monoxide when the detected value exceeds the set value. The atmosphere in the heating chamber is thus controlled to the conditions optimum for a bright heat treatment.

Description

【発明の詳細な説明】 この発明は、光輝熱処理における炉気制御方法に関し、
とくに、加熱室に中性ガスを封入密閉するか、もしくは
中性ガスを流して炉外に放出させつつ行なう光輝熱処理
法において、加熱室内の残存酸素分圧を検出し、この検
出値と設定値とを比較して炭化水素ガス、還元性ガスも
しくはこれらのガスを発生する液体、あるいは酸化性ガ
スもしくはこのガスを発生する液体を導入して残存酸素
量を制御するとともに、加熱室内の残存−酸化炭素分圧
を検出して、この検出値が設定値を超えたときに中性ガ
スを導入して残存−酸化炭素量を制御することにより、
炉気を光輝熱処理に最も好適な条件に制御するようにし
たものである。[Detailed Description of the Invention] This invention relates to a furnace air control method in bright heat treatment,
In particular, in the bright heat treatment method in which the heating chamber is sealed with a neutral gas sealed or the neutral gas is flowed and released outside the furnace, the residual oxygen partial pressure in the heating chamber is detected, and this detected value and set value are In addition to controlling the amount of residual oxygen by introducing hydrocarbon gas, reducing gas, or a liquid that generates these gases, or oxidizing gas or a liquid that generates this gas, the remaining - oxidizing gas in the heating chamber is controlled. By detecting the carbon partial pressure and controlling the amount of residual carbon oxide by introducing neutral gas when this detected value exceeds the set value,
The furnace air is controlled to the most suitable conditions for bright heat treatment.

従来、被処理金属の雰囲気熱処理において、酸化、脱炭
、浸炭、スーテイング等を生じさせずに被処理金属を加
熱する方法として、種々の炉気制両方法が提案されてい
る。たとえば、炉内を大気圧よシ低い圧力まで減圧し、
その後、炉内圧力が大気圧か、その前後の圧力となるま
で窒素ガスにプロパンガス等の炭化水素ガスを適宜添加
して導入し、次いで、炉内を昇温して炉内温度がほぼ７
２３℃を超えた時点から酸素分析装置によって炉内の残
存酸素量を検出し、その検出値が設定値よシも高い場合
は炭化水素ガスを導入し、炉内酸素と反応させて一酸化
炭素や水素ガス等の還元性ガスに変え、検出値が設定値
よりも低い場合は、空気等の酸化性ガスを導入して残存
酸素量が一定値を保持するように制御する方法が知られ
ている（特公昭５６−２５２５４号公報参照）。Conventionally, various furnace air control methods have been proposed as methods for heating the metal to be treated without causing oxidation, decarburization, carburization, sooting, etc. in the atmospheric heat treatment of the metal to be treated. For example, by reducing the pressure inside the furnace to a pressure lower than atmospheric pressure,
After that, a hydrocarbon gas such as propane gas is appropriately added to the nitrogen gas and introduced until the pressure inside the furnace reaches atmospheric pressure or around it, and then the temperature inside the furnace is raised until the temperature inside the furnace reaches approximately 7.
Once the temperature exceeds 23°C, an oxygen analyzer detects the amount of oxygen remaining in the furnace. If the detected value is higher than the set value, hydrocarbon gas is introduced and reacts with the oxygen in the furnace to remove carbon monoxide. There is a known method to control the amount of residual oxygen by changing it to a reducing gas such as oxygen or hydrogen gas, and if the detected value is lower than the set value, introducing an oxidizing gas such as air to maintain the residual oxygen amount at a constant value. (Refer to Japanese Patent Publication No. 56-25254).

この制御方法によると、旧来のプロパンガス等の炭化水
素ガス、またはアルコール等の有機溶剤を窒素ガスに添
加した雰囲気ガスを多量に流しながら加熱処理する方法
や、被処理金属に酸化防止剤を塗布して酸化雰囲気（大
気）中、または窒素雰囲気中で加熱処理する方法に比べ
、酸化、脱炭等は皆無であり、高価な真空熱処理法によ
らず所期の目的を経済的かつ効果的に達成し得る利点が
ある。According to this control method, the conventional method of heat treatment while flowing a large amount of hydrocarbon gas such as propane gas or atmospheric gas in which an organic solvent such as alcohol is added to nitrogen gas, or the method of applying an antioxidant to the metal to be treated. Compared to heat treatment in an oxidizing atmosphere (air) or nitrogen atmosphere, there is no oxidation, decarburization, etc., and the desired purpose can be achieved economically and effectively without relying on expensive vacuum heat treatment. There are benefits that can be achieved.

しかしながら、上記の炉気制御方法は、被処理金属の表
面に水分や酸化物、あるいは油脂類が付着している場合
には、炉内雰囲気を密閉した状態で熱処理を行ったとき
でも、酸化、脱炭を防止する点ではすぐれた効果を収め
得るが、その反面、炉内に一酸化炭素が過剰に生成され
るため、浸炭防止の点では必ずしも満足すべき効果が得
られないという問題がある。However, the above furnace air control method does not allow oxidation or oxidation, even when heat treatment is performed with the furnace atmosphere sealed, when moisture, oxides, or oils and fats adhere to the surface of the metal to be treated. Although it can have an excellent effect in preventing decarburization, there is a problem in that it does not necessarily have a satisfactory effect in preventing carburization because excessive carbon monoxide is generated in the furnace. .

すなわち、被処理金属の表面に水分や酸化物が付着して
いると、被処理金属中の炭素［Ｃ］ｒとＨ２Ｏ，０２、
ＣＯ２等の酸化性ガスとが作用して下記式（１）ないし
く５）の反応により脱炭が起る。In other words, if moisture or oxides adhere to the surface of the metal to be treated, carbon [C]r and H2O,02 in the metal to be treated,
Decarburization occurs through the reaction of the following formulas (1) to 5) under the action of an oxidizing gas such as CO2.

〔Ｃ′３ｒ＋Ｈ２Ｏ２Ｈ２＋ＣＯ（１）［Ｃ］ｒ　＋２
Ｈ２０ｄ　２Ｈ２＋　ＣＯ２（２１［Ｃ）　ｒ　＋　０
２　：　ＣＯ２（３）２［Ｃ］ｒ　＋０２　：　２ＣＯ
（４）［Ｃ］ｒ　＋ＣＯ２：　２ＣＯ１５） 上記の脱炭を防止するために、プロパン（Ｃ３ＨＩｌ）
等の炭化水素ガスを導入して、酸化性ガスと反応させる
と、下記式（６）ないしく８）によりＣＯガス、Ｈ２ガ
スが生成する。[C'3r+H2O2H2+CO(1)[C]r +2
H20d 2H2+ CO2(21[C) r + 0
2: CO2(3)2[C]r +02: 2CO
(4) [C]r +CO2: 2CO15) In order to prevent the above decarburization, propane (C3HIl)
When a hydrocarbon gas such as the following is introduced and reacted with an oxidizing gas, CO gas and H2 gas are generated according to the following formulas (6) to 8).

２ｃ、ａｇ　＋　３０２　：　６ＣＯ＋４Ｈ２（６）２
Ｃ，Ｈｇ＋３Ｈ２０；！　３ＣＯ＋７Ｈ２１力２Ｃ，Ｈ
ｇ　＋３Ｃ０２：　６ＣＯ＋４Ｈ２（８）また、被処理
金属の表面に油脂類が付着している場合は、油脂類が加
熱分解して炭素として析出するので、これを防止するた
めに、空気等の酸化性ガスを導入して炭素と反応させる
と、下記式（９）および０ｅによりｏガスが生成する。2c, ag + 302: 6CO+4H2(6)2
C, Hg+3H20;! 3CO+7H21 force 2C,H
g +3C02: 6CO+4H2 (8) In addition, if oils and fats adhere to the surface of the metal to be treated, the oils and fats will be thermally decomposed and precipitated as carbon. When a gas is introduced and reacted with carbon, o gas is generated according to the following formula (9) and Oe.

Ｃ＋０２　；！　ＣＯ２（ｇ） ２Ｃ＋　ｏ２＝　２ＣＯ（１０） 上記のように、プロパン等の炭化水素ガスと空気等の酸
化性ガスとの何れのガスを導入する場合でも・２れらの
ガ３０導入によ？て００ガ７力゛生成されるから、炉内
を密閉して熱処理を行なうと、ＣＯガスが炉内に蓄積さ
れることになり、その濃度が一定限度を超えるとＣＯガ
スによる浸炭の問題を者膚する必要性が生じてくる。C+02 ;! CO2 (g) 2C+ o2 = 2CO (10) As mentioned above, regardless of whether a hydrocarbon gas such as propane or an oxidizing gas such as air is introduced, what is the difference between the two gases 30? Therefore, if the furnace is sealed and heat treatment is performed, CO gas will accumulate in the furnace, and if the concentration exceeds a certain limit, the problem of carburization due to CO gas will occur. The need to expose oneself to others arises.

ｃｏ　＋　ｃｏ　２系における浸炭反応式により雰囲気
ガスの炭素濃度を計算すると次のようになる。The carbon concentration of the atmospheric gas is calculated as follows using the carburizing reaction equation in the co + co 2 system.

Ｂｏｕｄｏｕａｒｄの浸炭反応は、下記式（１１１によ
り示される。Boudouard's carburizing reaction is represented by the following formula (111).

２ＣＯ：　［ｃ）ｒ　＋　ｃｏ２（ｉｌｌ上式（１１１
における平衡恒数には、下記式住って与えられる。2CO: [c)r + co2(ill above formula (111
The equilibrium constant in is given by the following formula.

ここに、ｐｃｏ　ｌ　ＰＣＯ２はそれぞれＣｏ　、　Ｃ
Ｏ２（７）分圧、ａは飽和度であり、 上式〇２＋およびａ３からＣ２０をめると、一方、平衡
恒数には、 ここに、Ｔ＝Ｆ’＋４６０ いま、炉内温度９０゛０℃における雰囲気ガス中のＣＯ
ガス濃度％を３３．２４．１５．５．３．１として残存
酸素分圧Ｐｏ２が１．ＩＶの一定値となるように制御し
た場合、ＣＯ／ＣＯ２＃１００となシ、飽和炭素濃度Ｃ
Ｐｅは１．２５であり、平衡恒数には弐〇５１から３１
．６５となるから、それぞれのＣＯガス濃度における平
衡炭素濃度ＣＰｅを０４式からめると次表に示すように
なる。Here, pco l PCO2 are Co and C, respectively.
O2 (7) partial pressure, a is the degree of saturation, and when C20 is subtracted from the above equations 〇2+ and a3, on the other hand, the equilibrium constant is: Here, T = F' + 460 Now, the furnace temperature is 90゛CO in atmospheric gas at 0°C
Assuming that the gas concentration % is 33.24.15.5.3.1, the residual oxygen partial pressure Po2 is 1. When IV is controlled to a constant value, CO/CO2 #100 and the saturated carbon concentration C
Pe is 1.25, and the equilibrium constant is 2051 to 31.
．． 65, the equilibrium carbon concentration CPe at each CO gas concentration can be calculated using equation 04 as shown in the following table.

上記の計算結果から明らかなように、ＣＯガス濃度が３
％以上になると、平衡炭素濃度ｃｐ、が０．１１８チ以
上となるから、この濃度で浸炭の可能性のある被処理金
属では必要かつ十分な光輝性が得られないことになる。As is clear from the above calculation results, the CO gas concentration is 3
% or more, the equilibrium carbon concentration, cp, becomes 0.118 or more, so that necessary and sufficient brightness cannot be obtained with the metal to be treated, which is likely to be carburized at this concentration.

この発明は、上記の問題を解決するためになされたもの
でアシ、この発明の目的は、被処理金属の表面に水分、
酸化物、油脂類が付着している場合でも、酸化、脱炭、
浸炭を生ずることがない光輝熱処理を行なうことにあり
、またこの発明の目的は、炉内の残存酸素量と残存−酸
化炭素量とを制御しながら行なう光輝熱処理法を提供す
ることにある。This invention was made in order to solve the above problem, and the purpose of this invention is to prevent moisture from forming on the surface of the metal to be treated.
Even when oxides and oils are attached, oxidation, decarburization,
It is an object of the present invention to perform a bright heat treatment that does not cause carburization, and another object of the present invention is to provide a bright heat treatment method that can be performed while controlling the amount of oxygen remaining in the furnace and the amount of residual carbon oxide.

すなわち、この発明は、加熱室と冷却室とを有する熱処
理炉の少なくとも加熱室に中性ガスを封入して密閉する
か、もしくは中性ガスを流して炉外に放出させながら行
なう光輝熱処理法において、加熱室内の残存酸素分圧を
検出して、該検出値が設定値よりも高いときは炭化水素
ガス、還元性ガス、あるいはこれらのガスを生じる液体
を、該検出値が設定値よりも低いときは酸化性ガス、あ
るいは酸化性ガスを生じる液体をそれぞれ加熱室内に導
入して残存酸素量を制御するとともに、加熱室内の残存
−酸化炭素分圧を検出して、該検出値が設定値を超えた
ときに中性ガスを加熱室内に流しながら炉外に放出させ
て残存−酸化炭素量を制御することを特徴とする光輝熱
処理における炉気制御方法に係る。That is, the present invention provides a bright heat treatment method in which at least the heating chamber of a heat treatment furnace having a heating chamber and a cooling chamber is filled with a neutral gas and sealed, or the neutral gas is caused to flow and discharged outside the furnace. , detects the residual oxygen partial pressure in the heating chamber, and when the detected value is higher than the set value, removes hydrocarbon gas, reducing gas, or the liquid that produces these gases, and the detected value is lower than the set value. At the same time, the amount of residual oxygen is controlled by introducing an oxidizing gas or a liquid that produces an oxidizing gas into the heating chamber, and the residual-carbon oxide partial pressure in the heating chamber is detected, and the detected value matches the set value. This relates to a furnace air control method in bright heat treatment characterized by controlling the amount of residual carbon oxide by flowing neutral gas into the heating chamber and releasing it outside the furnace when the amount exceeds the amount of carbon oxide.

以下、この発明の方法を、第１図に示した熱処理炉を用
いて実施する場合について説明する。この熱処理炉は、
トレープッシャ一式の連続焼準炉であり、前部パージ室
１０、加熱室１１、冷却室１２および後部パージ室１３
から構成され、前部パージ室１０の側面にはエアシリン
ダ１５によつシリンダ１７．１９によって開閉する真空
扉１８と断熱扉２０とを介して連続し、加熱室１１と冷
却室１２との間は、エアシリンダ２１によって開閉する
断熱扉２２を介して連続し、冷却室１２と後部パージ室
１３との間は、エアシリンダ２３によって開閉する真空
扉２４を介して連続し、後部パージ室１３の出口側には
、エアシリンダ２５によって開閉する真空扉２６が設け
である。Hereinafter, the case where the method of the present invention is implemented using the heat treatment furnace shown in FIG. 1 will be explained. This heat treatment furnace is
It is a continuous normalizing furnace with a tray pusher set, and includes a front purge chamber 10, a heating chamber 11, a cooling chamber 12, and a rear purge chamber 13.
The side of the front purge chamber 10 is connected to the heating chamber 11 and the cooling chamber 12 through a vacuum door 18 and an insulating door 20, which are opened and closed by an air cylinder 15 and a cylinder 17, 19. The cooling chamber 12 and the rear purge chamber 13 are connected through a vacuum door 24 that is opened and closed by an air cylinder 23. A vacuum door 26 that is opened and closed by an air cylinder 25 is provided on the exit side.

上記熱処理炉の各室の底部には、レール２８が長さ方向
に敷設してあり、該レール２８にはトレー３０が載置さ
れ、このトレー３０に被処理金属１を載せて、前部パー
ジ室１０の入口側から油圧シリンダ３２によシ順次押し
出して移動させる。At the bottom of each chamber of the heat treatment furnace, a rail 28 is laid in the length direction, and a tray 30 is placed on the rail 28. The metal to be treated 1 is placed on this tray 30, and the front purge is carried out. They are sequentially pushed out and moved by the hydraulic cylinder 32 from the entrance side of the chamber 10.

すなわち、まず前部パージ室１０内を、排気弁４０を介
して接続されている真空ポンプ（図示せず）により大気
圧より低い圧力に減圧した後、電磁制御弁４１と流量計
４２とを介して接続されているＮ２ガスボンベ（図示せ
ず）からＮ２ガスを導入して大気圧前後の圧力としてか
ら、被処理金属１が前部パージ室１０内に搬入され、然
る後、真空扉１８と断熱扉２０とを開いて加熱室１１内
に送り込まれる。加熱室１１および冷却室１２のうち、
少なくとも加熱室１１には、前記電磁制御弁４１と流量
計４２とを介して一定量のＮ２ガスを封入して外部に漏
出させない密閉した状態とするか、あるいは適宜量のＮ
２ガスを流して放出弁４３．４５から外部に放出させる
状態として、加熱室１１内のＮ２ガスを攪拌機３３によ
り攪拌しながら発熱体３４により被処理金属１の加熱処
理が行なわれる。That is, first, the inside of the front purge chamber 10 is reduced to a pressure lower than atmospheric pressure by a vacuum pump (not shown) connected via the exhaust valve 40, and then the pressure is reduced to below atmospheric pressure via the electromagnetic control valve 41 and the flow meter 42. The metal to be processed 1 is introduced into the front purge chamber 10 after introducing N2 gas from a N2 gas cylinder (not shown) connected to the tank to bring the pressure to around atmospheric pressure. The heat insulating door 20 is opened and the heat is sent into the heating chamber 11. Of the heating chamber 11 and the cooling chamber 12,
At least the heating chamber 11 is sealed with a certain amount of N2 gas via the electromagnetic control valve 41 and the flow meter 42 to prevent leakage to the outside, or an appropriate amount of N2 gas is sealed.
The metal to be treated 1 is heated by the heating element 34 while the N2 gas in the heating chamber 11 is stirred by the stirrer 33, with the N2 gas flowing and being discharged to the outside from the release valves 43, 45.

この加熱処理がなされた被処理金属１は、断熱扉２２を
開いて冷却室１２内に送られ、冷却室１２内の空冷用送
風機３５と水冷用蛇管３６とによシ冷却される。次に後
部パージ室１３内を、排気弁４７を介して真空ポンプ（
図示せず）により大気圧より低い圧力に減圧し、さらに
Ｎ２ガスを大気圧前後の圧力となるまで導入した後に真
空扉２４を開いて冷却された被処理金属１が、後部パー
ジ室１３内に送り込まれる。前記の工程を経て後部パー
ジ室１３の真空扉２６を開いて被処理金属１が外部に搬
出される。The heat-treated metal 1 is sent into the cooling chamber 12 by opening the heat insulating door 22, and is cooled by the air-cooling blower 35 and the water-cooling corrugated pipe 36 inside the cooling chamber 12. Next, a vacuum pump (
(not shown) to reduce the pressure to lower than atmospheric pressure, and then introduce N2 gas until the pressure is around atmospheric pressure. After that, the vacuum door 24 is opened and the cooled metal 1 is transferred into the rear purge chamber 13. sent. After the above steps, the vacuum door 26 of the rear purge chamber 13 is opened and the metal to be processed 1 is carried out.

上記熱処理炉の加熱室１１には、前述したＮ２ガス導入
用の電磁制御弁４１および流量計４２のほかに、図示し
ないプロパン（Ｃ３Ｈ８）ガスボンベがｔ磁制御弁４９
と流量計５０とを介して、また、図示しない空気圧縮機
が、電磁制御弁５１と流量計５２とを介して、それぞれ
接続されている。また、加熱室１１には、酸素分析装置
（たとえば酸素濃淡電池）３７と一酸化炭素分析装置（
たとえば赤外線ＣＯ分析計）３８とが連結されている。In addition to the aforementioned electromagnetic control valve 41 and flowmeter 42 for introducing N2 gas, a propane (C3H8) gas cylinder (not shown) is installed in the heating chamber 11 of the heat treatment furnace.
and a flowmeter 50, and an air compressor (not shown) is connected via an electromagnetic control valve 51 and a flowmeter 52, respectively. The heating chamber 11 also includes an oxygen analyzer (for example, an oxygen concentration battery) 37 and a carbon monoxide analyzer (
For example, an infrared CO analyzer) 38 is connected.

上記の酸素分析装置３７は、第２図に示すように、酸素
分圧設定部５５と調節アンプ５６とを有する調節計５４
に接続され、該調節計５４の調節アンプ５６には、Ｃ５
Ｈ８ガス導入用の電磁制御弁４９と空気導入用の電磁制
御弁５１とを接続して、酸素分析装置３７によって加熱
室１１内の残存酸素分圧を検出し、その検出値を調節計
５４に出力して調節計５４の酸素分圧設定部５５の設定
値と比較し、検出値が設定値よりも高いときは、調節ア
ンプ５６の信号をＣうＨｇガス導入用の電磁制御弁４９
に出力して該電磁制御弁４９を作動させ、これと反対に
検出値が設定値よりも低いときは、調節アンプ５６の信
号を空気導入用の電磁制御弁５１に出力して該電磁制御
弁５１を作動させるようにしである。As shown in FIG.
C5 is connected to the control amplifier 56 of the controller 54.
The electromagnetic control valve 49 for introducing H8 gas and the electromagnetic control valve 51 for introducing air are connected, the residual oxygen partial pressure in the heating chamber 11 is detected by the oxygen analyzer 37, and the detected value is sent to the controller 54. The output is compared with the set value of the oxygen partial pressure setting section 55 of the controller 54, and when the detected value is higher than the set value, the signal of the regulating amplifier 56 is outputted to the electromagnetic control valve 49 for introducing Hg gas.
On the other hand, when the detected value is lower than the set value, a signal from the regulating amplifier 56 is output to the air introduction solenoid control valve 51 to operate the solenoid control valve 49. 51 is to be activated.

また、上記の一酸化炭素分析装置３８も、同様に一酸化
炭素分圧設定部５８と調節アンプ５９表を有する調節計
５７に接続され、該調節計５７の調節アンプ５９にはＮ
２ガス導入用の電磁制御弁４１を接続して、−酸化炭素
分析装置３８によって加熱室１１内の残存−酸化炭素分
圧を検出し、その検出値を調節計５７に出力して調節計
５７の一酸化炭素分圧設定部５８の設定値と比較し、検
出値が設定値よりも高いときに調節アンプ５９の信号を
Ｎ２ガス導入用の電磁制御弁４１に出力して該電磁制御
弁４１を作動させるようにしである。Further, the carbon monoxide analyzer 38 is similarly connected to a controller 57 having a carbon monoxide partial pressure setting section 58 and an adjustment amplifier 59 table, and the adjustment amplifier 59 of the controller 57 has an N
The electromagnetic control valve 41 for introducing two gases is connected, and the residual carbon oxide partial pressure in the heating chamber 11 is detected by the carbon oxide analyzer 38, and the detected value is output to the controller 57. The detected value is compared with the set value of the carbon monoxide partial pressure setting section 58, and when the detected value is higher than the set value, a signal from the adjustment amplifier 59 is output to the electromagnetic control valve 41 for introducing N2 gas. It should be activated.

上記構成の炉気自動制御装置を用いると、被処理金属の
表面に、水分や酸化物が付着したまま加熱室１１内に搬
入された場合、加熱室１１内の雰囲気ガス中に酸化成分
が持ち込まれるため、ｏ２、ＣＯ２、■２０等の酸化性
ガスが発生して残存酸素量が増加するが、この残存酸素
分圧は酸素分析装置３７によって検出され、この検出値
が調節計５４の酸素分圧設定部５５の設定値よシも高く
なるから、調節アンプ５６の信号により、Ｃ５Ｈ８ガス
導入用の電磁制御弁４９を介してＣ３Ｈ８ガスが加熱室
１１内に導入される。これにより、酸化性ガスとＣ５Ｈ
ｇガスとが反応してＣ０１Ｈ２等の還元性ガスが生成さ
れるので、残存酸素量は一定に保持される。When the automatic furnace air control device having the above configuration is used, if the metal to be processed is brought into the heating chamber 11 with moisture or oxides attached to its surface, oxidizing components will be brought into the atmospheric gas in the heating chamber 11. As a result, oxidizing gases such as 02, CO2, and Since the set value of the pressure setting unit 55 also becomes higher, C3H8 gas is introduced into the heating chamber 11 via the electromagnetic control valve 49 for introducing C5H8 gas in response to a signal from the adjustment amplifier 56. As a result, oxidizing gas and C5H
Since reducing gas such as CO1H2 is generated by the reaction with g gas, the amount of residual oxygen is kept constant.

また、被処理金属の表面に、油脂類が付着したまま加熱
室１１内に搬入された場合には、油脂類の加熱分解によ
ｐ炭素が析出して残存酸素量が減少するが、この場合は
、酸素分析装置３７の検出値が調節計５４の酸素分圧設
定部５５の設定値よシも低くなるから、調節アンプ５６
の信号により、空気導入用の電磁制御弁５１を介して空
気が加熱室１１内に導入される。これにより、酸化性ガ
スが増加するので、残存酸素量は一定に保持される。In addition, if the metal to be treated is brought into the heating chamber 11 with oils and fats still attached to the surface, p-carbon will precipitate due to thermal decomposition of the oil and fats, and the amount of residual oxygen will decrease. Since the detected value of the oxygen analyzer 37 is lower than the set value of the oxygen partial pressure setting section 55 of the controller 54, the control amplifier 56
In response to this signal, air is introduced into the heating chamber 11 via the electromagnetic control valve 51 for air introduction. This increases the amount of oxidizing gas, so the amount of residual oxygen is kept constant.

さらに、上記のＣ３Ｈ，ガスまたは空気の導入によって
、加熱室１１内の雰囲気ガス中にＣＯガスが生成され、
これらの導入ガス量の増加に伴って残存−酸化炭素量が
増加するが、この残存−酸化炭素分圧は一酸化炭素分析
装置３８によって検出され、この検出値が調節計５７の
一酸化炭素分圧設定部５８の設定値よりも高くなるから
、調節アンプ５９の信号により、Ｎ２ガス導入用の電磁
制御弁４１を介してＮ２ガスが加熱室１１内に導入され
る。この場合、加熱室１１が密閉されているときは、放
出弁４３を開いてＮ２ガスをキャリアガスとして加熱室
１１に流しながら外部に放出させる。−これによシ、加
熱室１１内の雰囲気ガスがＮ２ガスによって希釈される
ので、残存−酸化炭素量は一足に保持される。Furthermore, by introducing the above-mentioned C3H, gas or air, CO gas is generated in the atmospheric gas in the heating chamber 11,
As the amount of introduced gas increases, the amount of residual carbon oxide increases, and this residual carbon oxide partial pressure is detected by the carbon monoxide analyzer 38, and this detected value is the carbon monoxide content of the controller 57. Since the pressure becomes higher than the set value of the pressure setting unit 58, N2 gas is introduced into the heating chamber 11 via the electromagnetic control valve 41 for N2 gas introduction in response to a signal from the adjustment amplifier 59. In this case, when the heating chamber 11 is sealed, the release valve 43 is opened to allow N2 gas to flow into the heating chamber 11 as a carrier gas and to be released to the outside. - Accordingly, the atmospheric gas in the heating chamber 11 is diluted by the N2 gas, so that the amount of residual carbon oxide is kept at a constant level.

上記の自動制御におけるＣ、Ｈ８ガス、空気およびＮ２
ガスの導入量は、被処理金属の表面の水分、酸化物、油
脂類の種類とその付着量によって異なるから、これらの
付着物に応じてそれぞれのガスの導入量をあらかじめ設
定して、各電磁制御弁の開度を調節アンプの出力信号に
よって制御する。C, H8 gas, air and N2 in the above automatic control
The amount of gas introduced varies depending on the types of moisture, oxides, oils and fats on the surface of the metal to be treated, and the amount of these substances. The opening degree of the control valve is controlled by the output signal of the control amplifier.

前述の炉気制御は、自動制御によるものであるが、酸素
分析装置および一酸化炭素分析装置の検出値を目視して
、Ｃ５Ｈ８ガス、空気およびＮ２ガスのそれぞれの制御
弁を手動で操作することもできる。The above-mentioned reactor air control is based on automatic control, but the control valves for C5H8 gas, air, and N2 gas can be manually operated by visually observing the detection values of the oxygen analyzer and carbon monoxide analyzer. You can also do it.

また、加熱室内に導入するガスは、Ｃ５Ｈ８ガスに限ら
ず、その他の炭化水素ガス、または還元性ガス、あるい
はこれらのガスを生じる液体を使用してもよく、まだ、
空気を導入する場合も空気以外の酸化性ガス、あるいは
酸化性ガスを生じる液体を使用してもよく、さらに、キ
ャリアガスとしてＮ２ガス以外の中性ガス−を導入して
もよい。Furthermore, the gas introduced into the heating chamber is not limited to C5H8 gas, but other hydrocarbon gases, reducing gases, or liquids that produce these gases may be used.
When introducing air, an oxidizing gas other than air or a liquid that produces an oxidizing gas may be used, and furthermore, a neutral gas other than N2 gas may be introduced as a carrier gas.

以上説明したところから明らかなように、この発明によ
れば、加熱室内の雰囲気ガスの残存酸素分圧を検出し、
設定値との高低に応じて雰囲気調整用のガスもしくは液
体を導入して残存酸素が一定量を保つように制御してい
るから、被処理金属の表面に水分、酸化物、油脂類が付
着している場合でも、酸化、脱炭、炭素析出等を生じさ
せることのない光輝熱処理を行なうことができるだけで
なく、雰囲気ガスの残存−酸化炭素分圧を検出して、そ
の検出値が設定値を超えたときは中性ガスを導入して炉
外に放出させることにより、残存−酸化炭素が一足量を
保つように制御しているから、浸炭が生ずることもなく
、きわめて光輝性にすぐれた熱処理が可能となる。As is clear from the above explanation, according to the present invention, the residual oxygen partial pressure of the atmospheric gas in the heating chamber is detected,
Since the atmosphere is controlled to maintain a constant amount of residual oxygen by introducing gas or liquid for atmosphere adjustment depending on the level of the setting value, moisture, oxides, oils and fats will not adhere to the surface of the metal being treated. In addition to being able to perform bright heat treatment without causing oxidation, decarburization, carbon precipitation, etc. even when When the amount exceeds the limit, neutral gas is introduced and released outside the furnace to control the amount of residual carbon oxide, so carburization does not occur and extremely bright shine is achieved. Heat treatment becomes possible.

【図面の簡単な説明】[Brief explanation of drawings]

第１図は、この発明の実施装置の一例を示す縦断面図、
第２図は炉気自動制御装置を示すブロック図である。 図中、１１は加熱室、１２は冷却室、３７は酸素分析装
置、３８は一酸化炭素分析装置、４１はＮ２ガス導入用
の電磁制御弁、イ９はＣ，Ｈ８ガス導入用の電磁制御弁
、５１は空気導入用の電磁制御弁である。FIG. 1 is a longitudinal sectional view showing an example of an implementation device of the present invention;
FIG. 2 is a block diagram showing the automatic reactor air control system. In the figure, 11 is a heating chamber, 12 is a cooling chamber, 37 is an oxygen analyzer, 38 is a carbon monoxide analyzer, 41 is an electromagnetic control valve for introducing N2 gas, and 9 is an electromagnetic control valve for introducing C and H8 gases. A valve 51 is an electromagnetic control valve for introducing air.

Claims (2)

【特許請求の範囲】[Claims] （１）　加熱室と冷却室とを有する熱処理炉の少なくと
も加熱室に中性ガスを封入して密閉するか、もしくは中
性ガスを流して炉外に放出させながら行なう光輝熱処理
法において、加熱室内の残存酸素分圧を検出して、該検
出値が設定値よりも高いときは炭化水素ガス、還元性ガ
ス、あるいはこれらのガスを生じる液体を、該検出値が
設定値よりも低いときは酸化性ガス、あるいは酸化性ガ
スを生じる液体をそれぞれ加熱室内に導入して残存酸素
量を制御するとともに、加熱室内の残存−酸化炭素分圧
を検出して、該検出値が設定値を超えたときに中性ガス
を加熱室内に流しながら炉外に放出させて残存−酸化炭
素量を制御することを特徴とする光輝熱処理における炉
気制御方法。(1) In the bright heat treatment method, in which at least the heating chamber of a heat treatment furnace having a heating chamber and a cooling chamber is filled with a neutral gas and sealed, or the neutral gas is flowed and released outside the furnace, the heating chamber is detects the residual oxygen partial pressure of The amount of residual oxygen is controlled by introducing an oxidizing gas or a liquid that produces an oxidizing gas into the heating chamber, and the residual-carbon oxide partial pressure in the heating chamber is detected, and when the detected value exceeds the set value. 1. A furnace air control method in bright heat treatment, characterized by controlling the amount of residual carbon oxide by flowing neutral gas into a heating chamber and releasing it outside the furnace. （２）酸素濃淡電池を用いて残存酸素分圧を検出し、赤
外線Ｃｏ分析計を用いて残存−酸化炭素分圧を検出する
特許請求の範囲第１項記載の光輝熱処理における炉気制
御方法。(2) The reactor air control method in bright heat treatment according to claim 1, wherein the residual oxygen partial pressure is detected using an oxygen concentration battery and the residual carbon oxide partial pressure is detected using an infrared Co analyzer.
JP6839884A 1984-04-07 1984-04-07 Method for controlling furnace atmosphere in bright heat treatment Pending JPS60215717A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP6839884A JPS60215717A (en) 1984-04-07 1984-04-07 Method for controlling furnace atmosphere in bright heat treatment

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP6839884A JPS60215717A (en) 1984-04-07 1984-04-07 Method for controlling furnace atmosphere in bright heat treatment

Publications (1)

Publication Number Publication Date
JPS60215717A true JPS60215717A (en) 1985-10-29

Family

ID=13372545

Family Applications (1)

Application Number Title Priority Date Filing Date
JP6839884A Pending JPS60215717A (en) 1984-04-07 1984-04-07 Method for controlling furnace atmosphere in bright heat treatment

Country Status (1)

Country Link
JP (1) JPS60215717A (en)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH03243717A (en) * 1990-02-21 1991-10-30 Furukawa Electric Co Ltd:The Furnace pressure control method for atmosphere heat treating furnace
BE1006007A3 (en) * 1989-12-26 1994-04-19 Tong Yang Nylon Co Ltd Process for setting the atmosphere in an oven for heat treatment.
WO2013146520A1 (en) 2012-03-27 2013-10-03 関東冶金工業株式会社 Method for heat treatment and heat treatment apparatus, and heat treatment system
WO2014007046A1 (en) 2012-07-04 2014-01-09 関東冶金工業株式会社 Heat treatment method, heat treatment device, and heat treatment system
EP4194570A1 (en) * 2021-12-10 2023-06-14 Linde GmbH Method and device for controlling carbon potential of an atmosphere

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5558326A (en) * 1978-10-19 1980-05-01 Trw Inc Method of heat treating iron member
JPS5625254A (en) * 1979-08-04 1981-03-11 Nippon Shiyuuhenki Kk Skew correction system

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5558326A (en) * 1978-10-19 1980-05-01 Trw Inc Method of heat treating iron member
JPS5625254A (en) * 1979-08-04 1981-03-11 Nippon Shiyuuhenki Kk Skew correction system

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
BE1006007A3 (en) * 1989-12-26 1994-04-19 Tong Yang Nylon Co Ltd Process for setting the atmosphere in an oven for heat treatment.
JPH03243717A (en) * 1990-02-21 1991-10-30 Furukawa Electric Co Ltd:The Furnace pressure control method for atmosphere heat treating furnace
WO2013146520A1 (en) 2012-03-27 2013-10-03 関東冶金工業株式会社 Method for heat treatment and heat treatment apparatus, and heat treatment system
US9581389B2 (en) 2012-03-27 2017-02-28 Kanto Yakin Kogyo Co., Ltd. Method for heat treatment, heat treatment apparatus, and heat treatment system
WO2014007046A1 (en) 2012-07-04 2014-01-09 関東冶金工業株式会社 Heat treatment method, heat treatment device, and heat treatment system
EP2871248A4 (en) * 2012-07-04 2015-12-16 Kanto Yakin Kogyo Co Ltd Heat treatment method, heat treatment device, and heat treatment system
EP4194570A1 (en) * 2021-12-10 2023-06-14 Linde GmbH Method and device for controlling carbon potential of an atmosphere
WO2023104344A1 (en) * 2021-12-10 2023-06-15 Linde Gmbh Method and device for controlling carbon potential of an atmosphere

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