JPS63207468A - Manufacture of roll for rolling - Google Patents
Manufacture of roll for rollingInfo
- Publication number
- JPS63207468A JPS63207468A JP3835087A JP3835087A JPS63207468A JP S63207468 A JPS63207468 A JP S63207468A JP 3835087 A JP3835087 A JP 3835087A JP 3835087 A JP3835087 A JP 3835087A JP S63207468 A JPS63207468 A JP S63207468A
- Authority
- JP
- Japan
- Prior art keywords
- outer shell
- molten metal
- mold
- arbor
- casting
- 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
Links
- 238000005096 rolling process Methods 0.000 title claims abstract description 13
- 238000004519 manufacturing process Methods 0.000 title claims description 19
- 238000010438 heat treatment Methods 0.000 claims abstract description 28
- 238000009750 centrifugal casting Methods 0.000 claims abstract description 22
- 229910052751 metal Inorganic materials 0.000 claims abstract description 19
- 239000002184 metal Substances 0.000 claims abstract description 19
- 229910001018 Cast iron Inorganic materials 0.000 claims abstract description 12
- 238000005266 casting Methods 0.000 claims abstract description 12
- 239000000463 material Substances 0.000 claims abstract description 11
- 230000005496 eutectics Effects 0.000 claims abstract description 10
- 238000000034 method Methods 0.000 claims description 21
- 150000001247 metal acetylides Chemical class 0.000 claims description 7
- 239000011257 shell material Substances 0.000 abstract description 40
- 239000002131 composite material Substances 0.000 abstract description 9
- 230000008021 deposition Effects 0.000 abstract 1
- 238000002844 melting Methods 0.000 description 5
- 230000008018 melting Effects 0.000 description 5
- 230000000694 effects Effects 0.000 description 4
- 229910052804 chromium Inorganic materials 0.000 description 3
- 239000011651 chromium Substances 0.000 description 3
- 238000001816 cooling Methods 0.000 description 3
- 239000000203 mixture Substances 0.000 description 3
- 239000012071 phase Substances 0.000 description 3
- 239000000126 substance Substances 0.000 description 3
- VYZAMTAEIAYCRO-UHFFFAOYSA-N Chromium Chemical compound [Cr] VYZAMTAEIAYCRO-UHFFFAOYSA-N 0.000 description 2
- 238000005336 cracking Methods 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 238000005098 hot rolling Methods 0.000 description 2
- 239000004576 sand Substances 0.000 description 2
- 238000003466 welding Methods 0.000 description 2
- 230000002411 adverse Effects 0.000 description 1
- 238000005054 agglomeration Methods 0.000 description 1
- 230000002776 aggregation Effects 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 238000005469 granulation Methods 0.000 description 1
- 230000003179 granulation Effects 0.000 description 1
- 230000006698 induction Effects 0.000 description 1
- 239000012774 insulation material Substances 0.000 description 1
- 230000001788 irregular Effects 0.000 description 1
- 239000007791 liquid phase Substances 0.000 description 1
- 238000010791 quenching Methods 0.000 description 1
- 230000000171 quenching effect Effects 0.000 description 1
- 230000000717 retained effect Effects 0.000 description 1
- 239000007790 solid phase Substances 0.000 description 1
- 230000006641 stabilisation Effects 0.000 description 1
- 238000011105 stabilization Methods 0.000 description 1
- 238000005496 tempering Methods 0.000 description 1
Abstract
Description
【発明の詳細な説明】
（産業上の利用分野）
本発明は、遠心鋳造法によって圧延用ロールを製造する
方法に係り、特に、耐摩耗性、耐熱き層性に優れた圧延
用複合ロールの製造方法に関するものである。Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a method for manufacturing rolling rolls by centrifugal casting, and in particular, to a method for manufacturing rolling rolls using a centrifugal casting method. This relates to a manufacturing method.
（従来の技術および問題点）
従来、熱間圧延用の遠心鋳造複合ロールは、遠心鋳造機
上を回転する鋳型に、まず外殻溶湯を鋳込み、外殻がほ
ぼ凝固した後、この外殻を内装した遠心鋳造鋳型にアー
バ溶湯を鋳込み、外殻とアーバとを冶金的に溶着一体化
せしめることにより製造されている。(Conventional technology and problems) Conventionally, centrifugal casting composite rolls for hot rolling have been manufactured by first casting a molten outer shell into a mold rotating on a centrifugal casting machine, and then casting the outer shell after the outer shell has almost solidified. It is manufactured by pouring arbor molten metal into an internal centrifugal casting mold and metallurgically welding the outer shell and arbor together.
そしてかかるロールは、鋳造後一旦室温まで降温させた
後、鋳型から取り出し、その化学成分や用途に応じて焼
入れ、焼戻し、残留応力低減、組織調整などの熱処理を
適宜行っている。また、特殊なものとして特開昭６１−
１２４５３２号公報で開示されたように鋳造後、−挙に
室温まで冷却せずに冷却途中で鋳型から取り出して所定
温度に保持し、前記熱処理の一部を済ませてしまうこと
もある。 −
このように、従来ロールに対する熱処理は、全て遠心鋳
造終了後、鋳型から取り出してから行っていた。After the roll is cast, the temperature is once lowered to room temperature, and then the roll is taken out of the mold and subjected to appropriate heat treatments such as quenching, tempering, residual stress reduction, and structure adjustment depending on its chemical composition and use. In addition, as a special item, JP-A-61-
As disclosed in Japanese Patent No. 124532, after casting, a part of the heat treatment may be completed by taking the material out of the mold during cooling and maintaining it at a predetermined temperature without cooling it to room temperature at all. - In this way, conventional heat treatment for rolls was performed after centrifugal casting was completed and after the rolls were removed from the mold.
ところで、本出願人は特願昭６１−１０７５５２号公報
において、鋳鉄の熱処理方法として、画期的な方法を提
案した。By the way, the present applicant proposed an innovative method for heat treating cast iron in Japanese Patent Application No. 107552/1982.
すなわち、網目状の共晶炭化物を有する鋳鉄を〔固相線
〕〜〔固相線＋８０°Ｃ〕の温度域に加熱し保持するこ
とにより、炭化物の円滑な凝集・粒状化が起こり、しか
もこのような炭化物の形状変化は耐摩耗性や耐肌荒れ性
並びに耐熱き裂性に影響を及ぼさないばかりか、靭性改
善効果によってこれらの特性を一段と向上させることが
できることを開示した。In other words, by heating and holding cast iron having network-like eutectic carbides in the temperature range from [solidus line] to [solidus line +80°C], smooth agglomeration and granulation of the carbides occur, and this It has been disclosed that such changes in the shape of carbides not only do not affect wear resistance, rough skin resistance, and heat cracking resistance, but also can further improve these properties by improving toughness.
そして、前記加熱・保持温度が固相線よりも低いと幾ら
長時間加熱・保持したとしても網目状共晶炭化物の形状
を本質的に変化させることが出来ず、一方、固相線より
も８０℃高いと被熱処理材が部分的に溶融し始めて元の
形状を保持できなくなるから、加熱・保持温度は〔固相
線〕〜〔固相線＋８０°Ｃ〕が良いことも開示した。If the heating and holding temperature is lower than the solidus line, no matter how long the heating and holding temperature is, the shape of the network-like eutectic carbide cannot be essentially changed; It was also disclosed that the heating and holding temperature should be between [solidus line] and [solidus line +80°C] because if the temperature is too high, the material to be heat treated will start to partially melt and will not be able to maintain its original shape.
しかし、本発明者が、鋭意検討したところ、被熱処理材
を同相線温度を越えるような温度に加熱・保持すると、
たとえ〔固相線〕〜〔同相線＋８０℃〕の温度であって
も、液相と固相の共存状態となり溶融部分を生じている
ため、小さな応力でも極めて容易に形状変化を来たすこ
とがねかった。However, after careful study by the present inventor, we found that if the material to be heat treated is heated and held at a temperature exceeding the in-phase line temperature,
Even if the temperature is between [solidus line] and [common mode line +80°C], the liquid phase and solid phase coexist, creating a molten part, so even a small stress can cause a shape change extremely easily. won.
つまり、熱間圧延用複合ロールの如き大形で大重量の物
を従来熱処理と同様に、鋳造終了後鋳型から取り出して
から外殻鋳鉄の〔固相線〕〜〔固相線＋８０°Ｃ〕の温
度域に加熱・保持すると、まず、外殻材よりも溶融温度
の低いアーム相が先に溶は始めてしまう他、ロール自身
の重量効果と高温軟化によ変形や表面しわなどの溶損障
害が誘発され、ロール形状を完全に維持することができ
ないという問題点が生じたのである。In other words, in the same way as with conventional heat treatment, a large and heavy object such as a composite roll for hot rolling is removed from the mold after casting and then heated to the [solidus line] to [solidus line +80°C] of the outer shell cast iron. When heated and maintained at a temperature range of This caused the problem that the roll shape could not be maintained completely.
このようにロールに生じた損傷は、たとえそれが極めて
軽微なものであったとしてもロールに対する熱的・力学
的負荷が益々過酷化し、製品の高品質化が要求される今
日においては、致命的な欠陥となるため、本発明の優れ
た効果を有する圧延用複合ロールの製造を実現するには
、この問題を避けて通ることはできない。Even if the damage caused to the rolls is extremely slight, it can be fatal in today's world where thermal and mechanical loads on rolls are becoming increasingly severe and high quality products are required. Therefore, this problem cannot be avoided in order to realize the production of a rolling composite roll having the excellent effects of the present invention.
本発明は、このような事情に鑑みてなされたものであり
、遠心鋳造途中で網目状の共晶炭化物を含有する鋳鉄か
らなる外殻のみを〔同相線〕〜〔固相線＋８０℃〕の温
度域に加熱・保持することにより圧延用ロールの耐摩耗
性、耐熱き裂性を一段と改善させる新規な製造方法を提
供せんとするものである。The present invention has been made in view of these circumstances, and only the outer shell made of cast iron containing network-like eutectic carbides is removed during centrifugal casting from [home phase line] to [solidus line +80°C]. The object of the present invention is to provide a new manufacturing method that further improves the wear resistance and heat cracking resistance of rolling rolls by heating and maintaining the rolls within a temperature range.
（問題点を解決するための手段）
本発明は、遠心鋳造法によってロールを製造する方法に
おいて、遠心鋳造機上を回転する鋳型に、まず網目状共
晶炭化物を現出する鋳鉄成分からなる外殻溶湯を鋳込み
、外殻を形成した後当該材料の〔固相線〕〜〔固相線＋
８０℃〕の温度域に加熱・保持し、しかる後アーバ溶湯
を鋳込み、冶金学的に両者を溶着一体化せしめることを
要旨とする圧延用複合ロールの製造方法である。(Means for Solving the Problems) The present invention provides a method for manufacturing rolls by centrifugal casting, in which a mold rotating on a centrifugal casting machine is provided with a cast iron component that first develops a network-like eutectic carbide. After casting the shell molten metal and forming the outer shell, the [solidus line] to [solidus line +
This is a method for producing a composite roll for rolling, which consists of heating and maintaining the roll at a temperature of 80° C., then pouring the molten metal into an arbor, and metallurgically welding and integrating the two.
なお、前記加熱・保持する時期は、外殻が完全に凝固し
た後でもよいし、完全に凝固しなくとも、前記加熱・保
持の熱処理が有効に働く状態になっておればよい。Note that the heating and holding may be performed after the outer shell is completely solidified, or may not be completely solidified as long as the heating and holding heat treatment is effective.
（作 用）
本発明に係る圧延用ロールの製造方法は、遠心鋳造法に
よってロールを製造する方法において、遠心鋳造機上を
回転する鋳型に、まず網目状共晶炭化物を現出する鋳鉄
成分からなる外殻溶湯を鋳込み、外殻を形成した後当該
材料の〔固相線〕〜〔固相線＋８０°Ｃ〕の温度域に加
熱・保持し、しかる後アーバ溶湯を鋳込み、冶金学的に
両者を溶着一体化せしめるものである為、遠心力効果に
より外殻層形状を常に同心円状に維持したまま、前記熱
処理を施すことができ、しかも外殻材よりも溶融温度の
低いアーバ材は、前記熱処理終了後に鋳込まれるため従
来のようなアーバ溶融の問題は根本的に生じない。(Function) The method for manufacturing a rolling roll according to the present invention is a method for manufacturing a roll by a centrifugal casting method, in which a cast iron component is first added to a mold rotating on a centrifugal casting machine, from which a cast iron component in which reticulated eutectic carbides appear. After casting the outer shell molten metal and forming the outer shell, it is heated and maintained in the temperature range of [solidus line] to [solidus line + 80°C] of the material, and then the arbor molten metal is poured and metallurgically Since the two are welded and integrated, the above heat treatment can be performed while the outer shell layer shape is always maintained concentrically due to the centrifugal force effect, and the arbor material has a lower melting temperature than the outer shell material. Since the casting is performed after the heat treatment is completed, the problem of arbor melting as in the prior art does not fundamentally occur.
つまり、本発明の製造方法により、従来前記熱処理の際
に生じた外殻層形状異状やアーバ溶融の問題が一挙に解
決されるのである。In other words, the manufacturing method of the present invention solves all the problems of outer shell layer shape irregularities and arbor melting that conventionally occurred during the heat treatment.
（実 施 例） 以下、本発明方法を添付図面に基づいて説明する。(Example) Hereinafter, the method of the present invention will be explained based on the accompanying drawings.
第１図は本発明方法の１例を説明するための概略図（傾
斜型遠心鋳造法）であり、図中１は外スリーブ、２は内
スリーブ、３は砂型、４は底板であり、これらで鋳型を
構成している。そしてこの鋳型はモータ５及び動力伝達
装置６によってローラ７上を回転せしめられるようにな
っている。FIG. 1 is a schematic diagram for explaining one example of the method of the present invention (inclined centrifugal casting method), in which 1 is an outer sleeve, 2 is an inner sleeve, 3 is a sand mold, and 4 is a bottom plate. The mold is made up of: This mold can be rotated on rollers 7 by a motor 5 and a power transmission device 6.
しかして、本発明方法はかかる構成の鋳型を高速回転さ
せながら、この鋳型内に外殻溶湯を鋳込み、この外殻溶
湯が第２図（イ）に示すように凝固した後、あるいは第
２図（ロ）に示すような未凝固状態の時に例えば第１図
に示す高周波誘導加熱等公知の小型加熱装置８を挿入し
て外殻溶湯の〔固相線〕〜〔固相線＋８０°Ｃ〕の温度
域に加熱し所定時間保持するのである。Therefore, in the method of the present invention, the molten outer shell is cast into the mold while rotating the mold having such a configuration at high speed, and after the molten outer shell has solidified as shown in FIG. 2(A), or as shown in FIG. When the molten metal is in an unsolidified state as shown in (b), a known small heating device 8 such as the high-frequency induction heating shown in FIG. It is heated to a temperature range of
そして、その後前記小型加熱装置８を鋳型内から取り外
し、外殻内面が凝固又は未凝固状態のときに、この外殻
材９を内装した鋳型にアーバ溶湯を鋳込むことにより、
外殻とアーバを冶金学的に完全に溶着一体化させて一体
複合ロールとするのである。Then, the small heating device 8 is removed from the mold, and when the inner surface of the outer shell is in a solidified or unsolidified state, the arbor molten metal is poured into the mold containing the outer shell material 9.
The outer shell and arbor are metallurgically completely welded together to form an integral composite roll.
かかる如くすることによって外殻層の形状異状及びアー
バ溶融の問題を解決することができる。By doing so, the problems of irregular shape of the outer shell layer and arbor melting can be solved.
なお、以上説明した本発明に係る製造方法は、複合ロー
ルに限らず一体物つまり外殻材とアーバが同一化学成分
でも同様に適用できることは言うまでもない。It goes without saying that the above-described manufacturing method according to the present invention can be applied not only to a composite roll but also to an integral body, that is, an outer shell material and an arbor having the same chemical composition.
次に、本発明方法により製品胴径φ７６０ｍ、胴長１７
８０ｍの複合高クロムロールを製造した結果について説
明する。Next, by the method of the present invention, a product with a body diameter of 760 m and a body length of 17
The results of manufacturing an 80 m composite high chromium roll will be explained.
■ 外殻として下記表に示す化学成分の高クロム鋳鉄溶
湯を用い、これを遠心鋳造機上で高速回転する鋳型内に
、１４１０ ’ｃの鋳込温度で鋳込んだ。(2) A high-chromium cast iron molten metal having the chemical composition shown in the table below was used as the outer shell, and this was cast into a mold rotating at high speed on a centrifugal casting machine at a casting temperature of 1410'C.
■ 外殻が完全に凝固した後、小型加熱装置を鋳型内に
挿入し、固相線直上の１２３０ ’Ｃに加熱し５時間保
持した。(2) After the shell was completely solidified, a small heating device was inserted into the mold, and the temperature was heated to 1230'C, just above the solidus line, and maintained for 5 hours.
■ 鋳型から小型加熱装置を取出し、外殻が再び完全に
凝固した後、外殻を内装した遠心鋳造用鋳型にアーバ材
として下記表に示したアーバ溶湯を１３５０ °ｃで鋳
込んで鋳型内を完全に満たした後、上端を押湯保温材で
カバーした。■ After the small heating device is removed from the mold and the outer shell is completely solidified again, the arbor molten metal shown in the table below is poured as an arbor material into the centrifugal casting mold with the outer shell inside at 1350 °C, and the inside of the mold is heated. After filling completely, the top end was covered with riser insulation material.
■ 完全に冷却した後、ロールを鋳型から出し、残留応
力低減熱処理及び組織安定化熱処理を施した。■ After cooling completely, the roll was taken out of the mold and subjected to residual stress reduction heat treatment and structure stabilization heat treatment.
□□−一
（単位：重量％）
このようにして製造された遠心鋳造複合高クロムロール
の外殻層形状は、同心円状であり、しかも溶損等は発見
されなかった。□□-1 (Unit: Weight %) The outer shell layer shape of the centrifugally cast composite high chromium roll manufactured in this manner was concentric circles, and no melting damage or the like was found.
また、硬度検査を行ったところ、外殻層硬度は表面でＨ
３７８であった。In addition, when we conducted a hardness test, the hardness of the outer shell layer was H at the surface.
It was 378.
さらに、外殻層組織を顕微鏡観察した結果、共晶炭化物
が、充分に凝集、粒状化しているのが確認された。Further, as a result of microscopic observation of the outer shell layer structure, it was confirmed that the eutectic carbide was sufficiently agglomerated and granulated.
なお、本実施例では、傾斜型遠心鋳造法を例に取って説
明をしたが、水平型、竪型などの遠心鋳造法によっても
同様に本発明の製造方法を実施することができることは
勿論である。Although the present embodiment has been explained by taking the inclined centrifugal casting method as an example, it goes without saying that the manufacturing method of the present invention can be similarly carried out using horizontal or vertical centrifugal casting methods. be.
（発明の効果）
以上説明したように、本発明に係る圧延用ロールの製造
方法は、遠心鋳造法によってロールを製造する方法にお
いて、遠心鋳造機上を回転する鋳型に、まず網目状共晶
炭化物を現出する鋳鉄成分からなる外殻溶湯を鋳込み、
外殻溶湯を形成した後当該材料の〔同相線〕〜〔固相線
＋８０’ｃ）の温度域に加熱・保持し、しがる後アーハ
溶湯を鋳込み、冶金学的に両者を溶着一体化せしめるも
のである為、網目状共晶炭化物を現出する鋳鉄からなる
外殻層のみをロール形状に悪影響を与えることなくその
〔固相線〕〜〔同相線＋８０”ｃ）の温度域に加熱・保
持することができる。(Effects of the Invention) As explained above, in the method for manufacturing a rolling roll according to the present invention, in a method for manufacturing a roll by centrifugal casting, a reticulated eutectic carbide is first added to a mold rotating on a centrifugal casting machine. The outer shell molten metal consisting of cast iron components is poured to reveal
After forming the outer shell molten metal, it is heated and maintained in the temperature range of [in-phase line] to [solidus line + 80'c) of the material concerned, and then the Aha molten metal is cast and metallurgically welded and integrated the two. Therefore, only the outer shell layer made of cast iron that reveals network-like eutectic carbides is heated to a temperature range of [solidus line] to [homeophase line + 80"c) without adversely affecting the roll shape.・Can be retained.
これによって耐摩耗性や靭性を一段と改善された圧延用
ロールが実現できるなど、産業上極めて有用な効果がも
たらされるのである。This brings about extremely useful effects industrially, such as the realization of rolling rolls with further improved wear resistance and toughness.
第１図は本発明に係る圧延用ロールの製造方法の１例を
説明するための概略図、第２図は本発明方法の具体的手
順を示すものであり、（イ）は一旦凝固させてから再加
熱、保持、冷却する例を、（ロ）は未凝固のままで所定
の温度に保持し、その後冷却する例をそれぞれあられし
たものである。
１は外スリーブ、２は内スリーブ、３は砂型、４は底板
、８は加熱装置、９は外殻材。
第１図Fig. 1 is a schematic diagram for explaining one example of the method for manufacturing a rolling roll according to the present invention, and Fig. 2 shows a specific procedure of the method of the present invention. (2) shows an example in which the material is reheated, held, and cooled, and (2) shows an example in which the material is held at a predetermined temperature in an unsolidified state and then cooled. 1 is an outer sleeve, 2 is an inner sleeve, 3 is a sand mold, 4 is a bottom plate, 8 is a heating device, and 9 is an outer shell material. Figure 1
Claims (1)
て、遠心鋳造機上を回転する鋳型に、網目状共晶炭化物
を現出する鋳鉄成分からなる外殼溶湯を鋳込み、外殻を
形成した後当該材料の〔固相線〕〜〔固相線＋８０℃〕
の温度域に加熱・保持し、しかる後アーバ溶湯を鋳込む
ことを特徴とする圧延用ロールの製造方法。(1) In a method of manufacturing rolls by centrifugal casting, a molten shell made of a cast iron component that reveals network-like eutectic carbides is cast into a mold rotating on a centrifugal casting machine, and after forming an outer shell, the material is [solidus line] ~ [solidus line +80℃]
1. A method for manufacturing a rolling roll, which comprises heating and maintaining the rolling roll at a temperature range of 1.0 and then casting molten metal into an arbor.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3835087A JPS63207468A (en) | 1987-02-20 | 1987-02-20 | Manufacture of roll for rolling |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP3835087A JPS63207468A (en) | 1987-02-20 | 1987-02-20 | Manufacture of roll for rolling |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS63207468A true JPS63207468A (en) | 1988-08-26 |
Family
ID=12522833
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP3835087A Pending JPS63207468A (en) | 1987-02-20 | 1987-02-20 | Manufacture of roll for rolling |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS63207468A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5355932A (en) * | 1992-03-06 | 1994-10-18 | Hitachi Metals, Ltd. | Method of producing a compound roll |
-
1987
- 1987-02-20 JP JP3835087A patent/JPS63207468A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5355932A (en) * | 1992-03-06 | 1994-10-18 | Hitachi Metals, Ltd. | Method of producing a compound roll |
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