JP2011252522A

JP2011252522A - Mechanical seal

Info

Publication number: JP2011252522A
Application number: JP2010125555A
Authority: JP
Inventors: Masamori Akamatsu; 正守赤松; Takeshi Yamanoi; 毅山野井
Original assignee: Nippon Pillar Packing Co Ltd
Current assignee: Nippon Pillar Packing Co Ltd
Priority date: 2010-06-01
Filing date: 2010-06-01
Publication date: 2011-12-15
Anticipated expiration: 2030-06-01
Also published as: JP5530808B2

Abstract

PROBLEM TO BE SOLVED: To provide a mechanical seal having excellent durability and reliability by suppressing increase of a friction coefficient even in severe environment, such as a condition without a sufficient lubricating liquid over a sliding part of a static sealing ring made of an SiC sliding material, or a dry condition.SOLUTION: In the mechanical seal which has a rotary sealing ring 2, the static sealing ring 4, and an elastic mechanism 5 pressing seal faces 2a and 4a of them to form a seal part S, the static seal ring 4 is configured with a seal ring part 4A having a seal face 4a and a supporting ring part 4B supporting the seal ring part 4A and fixed to a housing 3. The seal ring part 4A is formed with the SiC sliding material, in which a permeation leakage quantity F of the liquid per unit time from an outer circumferential face to an inner circumferential face of the ring-like body processed with a predetermined standard dimension is defined by inequality of 0.01 ml/24 hr≤F≤500 ml/hr. A supply flow channel 15, which internally introduces a sealing liquid f into the seal ring part 4A, is formed.

Description

本発明は、静止密封環の材料としてＳｉＣ摺動材を用いたメカニカルシールに関するものである。 The present invention relates to a mechanical seal using a SiC sliding material as a material for a stationary seal ring.

ＳｉＣ（炭化珪素）はメカニカルシールや軸受等の摺動材として優れた特性を持っているが、摺動部に十分な潤滑液が回り込まない状況やドライ状況においては摩擦係数が高くなり、異常磨耗を招き易いという不利も有している。そこで対策としては、ＳｉＣ摺動材にハイドロカットや溝加工を施したり、シール背面よりクエンチング等を実施する等の工夫が行われている。 SiC (silicon carbide) has excellent properties as a sliding material for mechanical seals and bearings, but the friction coefficient is high and abnormal wear occurs in situations where sufficient lubricating liquid does not flow into the sliding part or in dry conditions. There is also a disadvantage that it is easy to invite. Therefore, as countermeasures, contrivances such as hydrocutting and grooving of the SiC sliding material, quenching and the like from the back of the seal have been taken.

特許文献１においては、相対回転摺接する２つの密封環１，３の一方又は両方が、平均気孔径１０〜４０μｍの独立気孔が均一に配置されており且つ気孔率が３〜１０％である炭化珪素焼結材で構成される密封環を持つメカニカルシールが開示されている。これにより、相手密封環が炭化珪素等の硬質材製のもの又はカーボン等の軟質材製のものの何れである場合にも、相手密封環との間の潤滑性を大幅に向上させることができ、シール条件に拘わらず、耐摩耗性等の耐久性及びシール性に極めて優れたメカニカルシールの実現に寄与している。 In Patent Document 1, one or both of the two sealing rings 1 and 3 that are in relative sliding contact with each other are carbonized in which independent pores having an average pore diameter of 10 to 40 μm are uniformly arranged and the porosity is 3 to 10%. A mechanical seal having a sealing ring made of silicon sintered material is disclosed. Thereby, even when the mating seal ring is made of a hard material such as silicon carbide or a soft material such as carbon, the lubricity between the mating seal ring can be greatly improved, Regardless of the sealing conditions, it contributes to the realization of a mechanical seal that is extremely excellent in durability such as wear resistance and sealing performance.

特許文献２においては、炭化珪素焼結部品の結晶粒平均径が０．０１０から０．０３０ｍｍの大きさで、その結晶粒界の間に気孔が形成され、気孔の大きさが０．００１から０．０２０の範囲に形成されて気孔率が３から１０容量％のものとされる静止密封環を持つメカニカルシールが開示されている。これにより、強度に優れ、耐摩耗性、耐食性及び耐高温に優れ、メカニカルシールに好適な炭化珪素焼結部品としての静止密封環が得られる、と記載されている。 In Patent Document 2, the crystal grain average diameter of the sintered silicon carbide part is 0.010 to 0.030 mm, pores are formed between the crystal grain boundaries, and the pore size is 0.001. A mechanical seal with a stationary seal ring formed in the range of 0.020 and having a porosity of 3 to 10% by volume is disclosed. Thus, it is described that a static seal ring as a silicon carbide sintered part which is excellent in strength, excellent in wear resistance, corrosion resistance and high temperature resistance and suitable for a mechanical seal can be obtained.

特許文献３においては、平均粒子径が０．１以上、１０μｍ以下のα−ＳｉＣ粉末と、平均粒子径が０．１以上、１０μｍ以下のβ−ＳｉＣ粉末と、プラズマＣＶＤ法により気相合成された平均粒子径が０．１μｍ未満のＳｉＣ超微粉末とを所望の比率で混合してＳｉＣ混合粉末を得、このＳｉＣ混合粉末を加熱焼結して成る密封環を持つメカニカルシールが開示されている。これにより、炭化珪素焼結体の比抵抗値を低くすることができ、かつ、この比抵抗を広範囲に制御できる炭化珪素焼結体の比抵抗制御方法を提供できる、と記載されている。 In Patent Document 3, an α-SiC powder having an average particle diameter of 0.1 or more and 10 μm or less, a β-SiC powder having an average particle diameter of 0.1 or more and 10 μm or less, and vapor phase synthesis by a plasma CVD method. A mechanical seal having a sealing ring formed by mixing SiC ultrafine powder having an average particle diameter of less than 0.1 μm at a desired ratio to obtain SiC mixed powder and heating and sintering the SiC mixed powder is disclosed. Yes. Thus, it is described that the specific resistance value of the silicon carbide sintered body can be provided which can reduce the specific resistance value of the silicon carbide sintered body and can control the specific resistance over a wide range.

以上のように、ＳｉＣ摺動材を用いて密封環の耐摩耗性向上が図られたメカニカルシールはよく知られた技術である。しかしながら、シール対象流体の多様化やシール対象流体が摺動部に回り込まない条件下での使用では、ＳｉＣ摺動材製のメカニカルシール用密封環としの性能が十分に発揮され難いこともあり、前述のように、ハイドロカットや溝加工を施す対策があるが、加工が難しいとか、コストや手間が掛かるという慢性的な問題がある。 As described above, the mechanical seal in which the wear resistance of the sealing ring is improved by using the SiC sliding material is a well-known technique. However, diversification of the fluid to be sealed and use under conditions in which the fluid to be sealed does not go into the sliding portion, it may be difficult to fully exhibit the performance as a seal ring for mechanical seal made of SiC sliding material. As described above, there are measures to perform hydrocutting and grooving, but there are chronic problems such as difficulty in processing and cost and labor.

一方、カーボン、黒鉛、ＢＮ、ＭｏＳ₂ 、フッ素樹脂等の低摩擦材を含浸させる等、ＳｉＣ摺動材に自己潤滑性を有する材料を配合したものによる密封環を持つメカニカルシールも開発されているが、製造が難しくコストも非常に高いことから、使用用途が限られるものであった。このように、種々の利点を有するＳｉＣ摺動材製の密封環を、使用条件によっては摩擦係数が高くなって摩耗が早くなるという問題が解消又は抑制されたものとするには、さらなる改善の余地が残されていた。
特許第３５１７７１１号公報特開２００２−３３８３６８号公報特開平９−２５５４２８号公報 On the other hand, a mechanical seal having a sealing ring made of a material having a self-lubricating property mixed with a SiC sliding material, such as impregnating with a low friction material such as carbon, graphite, BN, MoS ₂ , or a fluororesin, has been developed. However, since the production is difficult and the cost is very high, the intended use is limited. As described above, in order to eliminate or suppress the problem that the friction coefficient is increased and the wear is accelerated depending on use conditions, the seal ring made of SiC sliding material having various advantages is further improved. There was room left.
Japanese Patent No. 3517711 JP 2002-338368 A JP-A-9-255428

本発明の目的は、鋭意研究を進めることにより、基本的にＳｉＣ摺動材を用いた静止密封環を持つものとしながら、摺動部に十分な潤滑液が回り込まない状況やドライ状況といった厳しい環境下においても、摩擦係数が高くなる不都合を抑制又は解消して、耐久性や信頼性に優れるメカニカルシールを実現して提供する点にある。 The object of the present invention is to have a stationary seal ring using SiC sliding material by conducting earnest research, and in a severe environment such as a situation where sufficient lubricating liquid does not flow into the sliding part and a dry situation Even below, it is in the point which implement | achieves and provides the mechanical seal which is excellent in durability and reliability, suppressing or canceling the disadvantage that a friction coefficient becomes high.

請求項１に係る発明は、回転軸１に相対回転不能に支持される回転密封環２と、ハウジング３に相対回転不能に支持される静止密封環４と、前記回転密封環２の回転側シール面２ａと前記静止密封環４の静止側シール面４ａとを互いに回転軸の軸心Ｘ方向に押付けてシール部Ｓを形成するための弾性機構５とを有して成るメカニカルシールにおいて、
前記静止密封環４が、前記静止側シール面４ａを有するシール輪部４Ａと、前記シール輪部４Ａを支持し、かつ、前記ハウジング３に相対回転不能に支持される支持輪部４Ｂとから構成され、
前記シール輪部４Ａが、これを所定の規格寸法に加工して成る環状体の外周面から内周面に向けての単位時間当りの液体の浸透漏れ量Ｆが、
０．０１ｍｌ／２４ｈｒ≦Ｆ≦５００ｍｌ／１ｈｒ
で規定されるＳｉＣ摺動材で形成されるとともに、
前記シール輪部４Ａに、前記ハウジング３を介して供給されてくるシール用液体ｆを内部導入するための供給流路１５が形成されていることを特徴とするものである。 The invention according to claim 1 includes a rotary seal ring 2 supported on the rotary shaft 1 so as not to be relatively rotatable, a stationary seal ring 4 supported on the housing 3 so as not to be relatively rotatable, and a rotary side seal of the rotary seal ring 2. A mechanical seal having an elastic mechanism 5 for pressing the surface 2a and the stationary seal surface 4a of the stationary seal ring 4 in the direction of the axis X of the rotation shaft to form the seal portion S;
The stationary sealing ring 4 includes a sealing ring portion 4A having the stationary side sealing surface 4a, and a supporting ring portion 4B that supports the sealing ring portion 4A and is supported by the housing 3 so as not to be relatively rotatable. And
The amount of permeation leakage F of the liquid per unit time from the outer peripheral surface to the inner peripheral surface of the annular body formed by processing the seal ring portion 4A into a predetermined standard dimension is
0.01ml / 24hr ≦ F ≦ 500ml / 1hr
And is formed of a SiC sliding material defined in
A supply flow path 15 for introducing the sealing liquid f supplied through the housing 3 into the seal ring portion 4A is formed.

請求項２に係る発明は、請求項１に記載のメカニカルシールにおいて、前記供給流路１５が前記シール部Ｓに貫通して前記回転密封環２の回転側シール面２ａで閉塞される先端開放状の内部流路１５Ｂを有して形成されていることを特徴とするものである。 The invention according to claim 2 is the mechanical seal according to claim 1, wherein the supply flow path 15 penetrates the seal portion S and is closed by the rotation-side seal surface 2a of the rotary seal ring 2. It is characterized by having an internal flow path 15B.

請求項３に係る発明は、請求項１又は２に記載のメカニカルシールにおいて、前記支持輪部４Ｂが、前記弾性機構５による付勢力を受け止めるべく前記軸心Ｘ方向で前記ハウジング３と前記シール輪部４Ａとの間に配置される第１支持輪３１と、前記ハウジング３に内嵌され、かつ、前記シール輪部４Ａ及び前記第１輪部３１との双方に外嵌されるとともに前記ハウジング３からのシール用流体ｆが供給される取込口１４を備える第２支持輪３２と、を有して構成されていることを特徴とするものである。 According to a third aspect of the present invention, in the mechanical seal according to the first or second aspect, the support ring portion 4B is configured so that the housing 3 and the seal ring are arranged in the direction of the axis X so as to receive a biasing force by the elastic mechanism 5. The first support wheel 31 disposed between the housing 4 and the housing 3, and the housing 3 is externally fitted to both the seal wheel 4 A and the first wheel 31. And a second support wheel 32 provided with an intake port 14 to which a sealing fluid f is supplied.

請求項４に係る発明は、請求項３に記載のメカニカルシールにおいて、前記供給流路１５が、前記シール輪部４Ａと前記第１支持輪３１との前記軸心Ｘ方向間に形成されて前記取込口１４に連通する径方向流路１５Ａと、前記径方向流路１５Ａの径内側端部に連通して前記静止側シール面４ａに向かって延びる軸心方向流路１５Ｂと、を有して構成されていることを特徴とするものである。 According to a fourth aspect of the present invention, in the mechanical seal according to the third aspect, the supply channel 15 is formed between the seal ring portion 4A and the first support ring 31 in the axial center X direction. A radial flow path 15A that communicates with the intake port 14, and an axial flow path 15B that communicates with the radially inner end of the radial flow path 15A and extends toward the stationary-side seal surface 4a. It is characterized by being configured.

請求項５に係る発明は、請求項１に記載のメカニカルシールにおいて、前記供給流路１５が、その終端が前記シール輪部４Ａの内部に位置する行止り状のものに形成されていることを特徴とするものである。 According to a fifth aspect of the present invention, in the mechanical seal according to the first aspect, the supply flow path 15 is formed in a dead end shape whose end is located inside the seal ring portion 4A. It is a feature.

請求項１の発明によれば、詳しくは実施形態の項にて説明するが、ＳｉＣ摺動材として十分な強度と硬度を有しながら、内部流路を用いてシール用液体をＳｉＣ摺動材に浸透させることができる。従って、その液体浸透によって程よく濡れている状態が維持でき、静止側シール面（摺動面）を常に液体雰囲気とすることが可能になる。そして、静止密封輪を構成するシール輪部を所定の規格寸法に加工して成る環状体の浸透漏れ量も定義することにより、製品によって異なる寸法の密封輪の漏れ量も直接又は換算して規定できる便利さがある。 According to the first aspect of the present invention, as will be described in detail in the section of the embodiment, the sealing liquid is supplied to the SiC sliding material using the internal channel while having sufficient strength and hardness as the SiC sliding material. Can penetrate. Therefore, the wet state can be maintained moderately by the liquid permeation, and the stationary-side sealing surface (sliding surface) can always be in a liquid atmosphere. And by defining the amount of seepage leak of the annular body formed by processing the seal ring part that constitutes the stationary seal ring to the specified standard size, the leak amount of the seal ring of different dimensions depending on the product is specified directly or converted. There is convenience that can be done.

さらに、ハウジングに支持される静止密封環におけるシール輪部であるＳｉＣ摺動材にシール用液体を供給する内部経路が形成されているから、回転している回転密封環をＳｉＣ摺動材製として内部流路を持たせる場合に比べて、シール用液体の供給経路構造が簡単で廉価に構成できる利点がある。そして、シール用液体が浸透してシール部に迅速に及ぶようになり、内部流路が形成されていないものに比べて、シール用液体の供給開始から実際にシール部に及ぶまでの応答時間が短縮化され、シール用液体がシール部へ及ぶ応答性に優れるものとなる。その結果、基本的にＳｉＣ摺動材によるシール輪部を有する静止密封環を備えるものとしながら、摺動部に十分な潤滑液が回り込まない状況やドライ状況といった厳しい環境下においても、摩擦係数が高くなる不都合を抑制又は解消して、耐久性や信頼性に優れるメカニカルシールを提供することができる。 Furthermore, since the internal path for supplying the sealing liquid to the SiC sliding material which is the seal ring portion in the stationary sealing ring supported by the housing is formed, the rotating rotary sealing ring is made of the SiC sliding material. Compared with the case of having an internal flow path, there is an advantage that the structure for supplying the sealing liquid supply path is simple and inexpensive. Then, the sealing liquid penetrates quickly and reaches the sealing portion, and the response time from the start of supplying the sealing liquid to actually reaching the sealing portion compared to the case where the internal flow path is not formed. It is shortened, and the responsiveness that the sealing liquid reaches the seal portion becomes excellent. As a result, the friction coefficient can be reduced even under severe conditions such as a situation where a sufficient amount of lubricating liquid does not flow into the sliding part and a dry situation, while basically including a stationary sealing ring having a sealing ring part made of SiC sliding material. It is possible to provide a mechanical seal excellent in durability and reliability by suppressing or eliminating the inconvenience of increasing.

そして、静止密封環が、静止側シール面を有するＳｉＣ摺動材製のシール輪部と、シール輪部を支持し、かつ、ハウジングに相対回転不能に支持される支持輪部との複数の部品で構成されているから、静止密封環全てをＳｉＣ摺動材で形成する場合に比べてＳｉＣ摺動材の体積を減らすことができる。また、複数部品化により、各部品単体における形状のシンプル化を図り、生産性に優れるようにすることも可能である。 The stationary seal ring includes a plurality of parts including a seal ring part made of SiC sliding material having a static seal surface and a support ring part that supports the seal ring part and is supported relative to the housing so as not to be relatively rotatable. Therefore, the volume of the SiC sliding material can be reduced as compared with the case where all the stationary sealing rings are formed of the SiC sliding material. In addition, by using a plurality of parts, the shape of each part can be simplified and the productivity can be improved.

請求項２の発明によれば、内部流路が静止密封環を貫通してシール部で閉塞される構造とされているので、シール用液体がより迅速にシール部に及ぶようになり、前述の応答性がより良くなる利点がある。 According to the invention of claim 2, since the internal flow path is configured to pass through the stationary sealing ring and closed by the seal portion, the sealing liquid reaches the seal portion more quickly. There is an advantage that the responsiveness is improved.

請求項３の発明によれば、支持輪部が、弾性付勢力を受け止めるべく軸心方向でハウジングとシール輪部との間に配置される第１支持輪と、ハウジングに内嵌され、かつ、シール輪部及び第１輪部との双方に外嵌されるとともにハウジングからのシール用流体が供給される取込口を備える第２支持輪と、を有して構成されるので、機能別に別部品とすることができて支持輪部の作り易さや生産性をより向上させることが可能になるという良さがある。 According to the invention of claim 3, the support wheel portion is fitted in the housing, the first support wheel disposed between the housing and the seal wheel portion in the axial direction so as to receive the elastic biasing force, and And a second support wheel that is externally fitted to both the seal wheel part and the first wheel part and has an intake port to which a sealing fluid is supplied from the housing. There is a merit that it can be used as a part, and it becomes possible to further improve the ease of making the support ring part and the productivity.

請求項４の発明によれば、静止密封環としての外周面からシール用流体を取り込むことができて、ハウジングの液路を単一等の少ないものとしながらも、静止密封環に形成される供給流路に無理なく円滑に、かつ、廉価にシール用液体をバランス良く供給することが可能となる利点が得られる。 According to the fourth aspect of the present invention, the sealing fluid can be taken in from the outer peripheral surface as the stationary sealing ring, and the supply formed in the stationary sealing ring while the number of liquid passages in the housing is reduced to a single unit. There is an advantage that it is possible to smoothly and inexpensively supply the sealing liquid in a balanced manner in the flow path without difficulty.

請求項５の発明によれば、シール輪部の供給流路を行止り状の内部流路としてあるので、ある程度の圧を持たせたシール用流体でもってしてＳｉＣ摺動材の内部に浸透させ、静止側シール面（摺動面）を液体雰囲気とすることが可能になる。この場合、静止側シール面には浸透による均一な分布状態でシール用流体を供給することが可能になる、という利点がある。 According to the invention of claim 5, since the supply flow path of the seal ring part is a dead-end internal flow path, it penetrates into the inside of the SiC sliding material with a sealing fluid having a certain pressure. This makes it possible to make the stationary seal surface (sliding surface) a liquid atmosphere. In this case, there is an advantage that the sealing fluid can be supplied to the stationary seal surface in a uniform distribution state by permeation.

メカニカルシール及びその構造を示す要部の断面図（実施例１）Sectional drawing of the principal part which shows a mechanical seal and its structure (Example 1) 静止密封環の浸透性測定用の実験装置を示す断面図Sectional view showing an experimental device for measuring the permeability of a stationary seal ring 図２の実験装置に試験液が満たされた状態の断面図FIG. 2 is a cross-sectional view of the test apparatus filled with the test solution. （ａ）複数の実施例及び比較例の各種特性図、（ｂ）は各実施例の気孔率と自己浸透性との表を示す図(A) Various characteristic diagrams of a plurality of examples and comparative examples, (b) is a diagram showing a table of porosity and self-permeability of each example ＳｉＣ摺動材の拡大表面状況を示し、（ａ）は実施例１、（ｂ）は実施例４The enlarged surface condition of a SiC sliding material is shown, (a) is Example 1, (b) is Example 4. ＳｉＣ摺動材の拡大表面状況を示し、（ａ）は比較例１、（ｂ）は比較例２、（ｃ）は比較例４The expansion | swelling surface condition of a SiC sliding material is shown, (a) is the comparative example 1, (b) is the comparative example 2, (c) is the comparative example 4. メカニカルシール用密封環の製造方法を示すブロック図Block diagram showing a method for manufacturing a sealing ring for a mechanical seal 実施例２によるメカニカルシールを示す要部の断面図Sectional drawing of the principal part which shows the mechanical seal by Example 2.

以下に、本発明によるメカニカルシール、ＳｉＣ製の静止用密封環、及びその製造方法の実施の形態を、図面を参照しながら説明する。 Embodiments of a mechanical seal, a static sealing ring made of SiC, and a manufacturing method thereof according to the present invention will be described below with reference to the drawings.

メカニカルシールＭは、図１に示すように、回転軸１に対してその軸心Ｘ方向に移動可能な状態で外嵌されて一体回転（相対回転不能）する回転密封環２と、ハウジング３に相対回動不能に内嵌される静止密封環４と、回転密封環２を静止密封環４に押付けてシール部Ｓを形成するための弾性機構５とを有して構成されている。つまり、このメカニカルシールＭは、ハウジング３と回転軸１との間を含む機内側（プロセス側）Ｐと、ハウジング３と回転軸１との間を含む機外側（大気側）Ｔとをシールするものであり、シール対象液体（プロセス液）としては、プラント設備等における水（工業用水、水道水）、薬液、原油関係液、洗浄液等が挙げられる。 As shown in FIG. 1, the mechanical seal M is attached to a rotating seal ring 2 that is externally fitted to the rotating shaft 1 so as to be movable in the direction of the axis X thereof, and rotates together with the rotating shaft 1. The stationary sealing ring 4 is fitted in such a manner that it cannot be rotated relative to the stationary sealing ring 4, and the elastic mechanism 5 for pressing the rotary sealing ring 2 against the stationary sealing ring 4 to form the seal portion S. That is, the mechanical seal M seals the machine interior (process side) P including the space between the housing 3 and the rotary shaft 1 and the machine exterior (atmosphere side) T including the space between the housing 3 and the rotary shaft 1. Examples of the liquid to be sealed (process liquid) include water (industrial water, tap water), chemical liquids, crude oil related liquids, cleaning liquids and the like in plant facilities and the like.

回転軸１の機内側には、軸ビス９で軸外周１ａに押圧係止される固定支持輪１３が外装され、その機外側には作用輪７が軸心Ｘ方向に移動可能に遊外嵌されており、軸心Ｘ方向に沿う姿勢でそれら固定支持輪１３と作用輪７とに亘って介装されるコイルばね８を軸心Ｘ回りの均等角度毎に配置することで弾性機構５が構成されている。そして、回転密封環２は、回転軸１に軸心Ｘ方向移動可能に外嵌される保持輪６の先端側に蜜内嵌又は圧入保持されており、保持輪６は、その基端軸部６ａが作用輪７の貫通孔７ａに挿入されてその作用輪７と一体回転するように構成されている。保持輪６と回転軸１との間にはシール用のＯリング１２が介装され、保持輪６と作用輪７との間にも一対のＯリング３７，３８が介装されている。従って、コイルばね８の付勢力が作用輪７と保持輪６とを介して回転密封環２に作用する。 A fixed support wheel 13 that is pressed and locked to the shaft outer periphery 1a by a shaft screw 9 is externally mounted on the inner side of the rotary shaft 1, and a working wheel 7 is loosely fitted on the outer side of the rotary shaft 1 so as to be movable in the axis X direction. The elastic mechanism 5 is arranged by arranging the coil springs 8 interposed between the fixed support wheel 13 and the working wheel 7 at equal angles around the axis X in a posture along the direction of the axis X. It is configured. The rotary seal ring 2 is nipped or press-fitted and held on the distal end side of a holding ring 6 that is fitted to the rotary shaft 1 so as to be movable in the axial center X direction. 6 a is configured to be inserted into the through hole 7 a of the working wheel 7 and rotate integrally with the working wheel 7. A sealing O-ring 12 is interposed between the holding wheel 6 and the rotating shaft 1, and a pair of O-rings 37 and 38 are also interposed between the holding wheel 6 and the working wheel 7. Therefore, the urging force of the coil spring 8 acts on the rotary seal ring 2 via the action wheel 7 and the holding ring 6.

ハウジング３には、静止密封環４が、軸心Ｘ方向で機外側Ｔへの移動、及び軸心Ｘ回りの回動ができないように、かつ、回転軸１には遊外嵌される状態で内嵌されている。回転密封環２は弾性機構５によって機外側Ｔに押圧付勢されており、従ってその機外側の側周面である回転側シール面２ａと静止密封環４の機内側の先端側周面である静止側シール面４ａとが軸心Ｘ方向で互いに圧接され、それによって環状のシール部Ｓが形成されている。尚、回転密封環２はカーボン又はその他の材料によって形成されている。 In the housing 3, the stationary sealing ring 4 is in a state in which the stationary sealing ring 4 cannot be moved to the machine outside T in the direction of the axis X and cannot be rotated around the axis X and is loosely fitted to the rotary shaft 1. It is fitted inside. The rotary seal ring 2 is pressed and urged toward the machine outer side T by the elastic mechanism 5, and therefore, the rotary side seal surface 2 a which is the side peripheral surface of the machine outside and the tip side peripheral surface inside the machine of the stationary seal ring 4. The stationary seal surface 4a is in pressure contact with each other in the direction of the axis X, whereby an annular seal portion S is formed. The rotary seal ring 2 is made of carbon or other material.

静止密封環４は、静止側シール面４ａを有するシール輪部４Ａと、シール輪部４Ａを支持し、かつ、ハウジング３に相対回転不能に支持される支持輪部４Ｂとから構成され、支持輪部４Ｂは、第１支持輪１７と第２支持輪１８とから構成されている。つまり、静止密封環４は、シール輪部４Ａと第１支持輪１７と第２支持輪１８との３部品で構成されている。シール輪部４Ａは、静止側シール面４ａを持つ環状主部１９、及び環状主部１９の内周側から軸心Ｘ方向に延びる筒軸部分３９を有しており、環状主部１９には、軸心Ｘ方向に沿って貫通する横流路１５Ｂが周方向の複数箇所に形成されるとともに、静止側シール面４ａには、横流路１５Ｂに連通する冷却水充填用の側周溝１６が形成されている。側周溝１６は、軸心Ｘに関する環状のものが望ましいが、複数箇所の横流路１５Ｂ毎に対応して設けられる軸心Ｘに関する所定角度の円弧状のもの（周方向に間欠配置される複数の側周溝）でも良い。 The stationary sealing ring 4 includes a sealing ring portion 4A having a stationary side seal surface 4a, and a supporting ring portion 4B that supports the sealing ring portion 4A and is supported by the housing 3 so as not to be relatively rotatable. The part 4 B includes a first support wheel 17 and a second support wheel 18. That is, the stationary seal ring 4 is composed of three parts, that is, the seal ring portion 4A, the first support ring 17 and the second support ring 18. The seal ring portion 4A has an annular main portion 19 having a stationary side seal surface 4a, and a cylindrical shaft portion 39 extending in the axial center X direction from the inner peripheral side of the annular main portion 19, The transverse flow path 15B penetrating along the axis X direction is formed at a plurality of locations in the circumferential direction, and the cooling water filling side circumferential groove 16 communicating with the lateral flow path 15B is formed on the stationary side seal surface 4a. Has been. The side circumferential grooves 16 are preferably annular with respect to the axis X, but are arc-shaped with a predetermined angle with respect to the axis X provided corresponding to each of the plurality of lateral flow paths 15B (a plurality of intermittently arranged in the circumferential direction). Side circumferential groove).

支持輪部４Ｂは、弾性機構５による付勢力を受け止めるべく軸心Ｘ方向でハウジング３の内向きフランジ３Ｆとシール輪部４Ａとの間に配置される第１支持輪３１と、ハウジング３に内嵌され、かつ、シール輪部４Ａ及び第１輪部３１との双方に外嵌されるとともにハウジング３からのシール用流体ｆが供給される取込口１４を備える第２支持輪３２と、を有して構成されている。第１支持輪３１は、筒軸部分３９にＯリング３３を伴って外嵌し、かつ、Ｏリング３４を伴って内嵌される嵌合筒部３１Ａと、回転軸１に遊外嵌され、かつ、内向きフランジ３Ｆに軸心Ｘ方向で当接する支持筒部３１Ｂとを有する環状体に形成されている。嵌合筒部３１Ａには、周方向の複数箇所に軸心Ｘ方向でシール輪部４Ａに向けて張出して環状主部１９の側壁１９ａに当接可能な突出部分３５が形成されている。この突出部分３５の存在により、支持筒部３１Ｂにおける突出部分３５の基端面である内奥側周面３１ｂとの軸心Ｘ方向間に縦流路１５Ａが形成されている。また、支持筒部３１Ｂから軸心Ｘ方向で機外側に突出するピン部３１ｐと内向きフランジ３Ｆの孔部３ｋとの嵌合構造により、支持筒部３１Ｂ、即ち静止密封輪４の回り止めが為されている。 The support ring portion 4B includes a first support ring 31 disposed between the inward flange 3F of the housing 3 and the seal ring portion 4A in the axis X direction so as to receive the urging force of the elastic mechanism 5, and the housing 3 A second support wheel 32 that is fitted and is fitted to both the seal wheel portion 4A and the first wheel portion 31 and includes the intake port 14 to which the sealing fluid f from the housing 3 is supplied. It is configured. The first support wheel 31 is externally fitted to the rotary shaft 1 with a fitting cylinder portion 31A fitted to the cylindrical shaft portion 39 with the O-ring 33 and fitted with the O-ring 34, And it is formed in the annular body which has the support cylinder part 31B contact | abutted to the inward flange 3F in the axial center X direction. The fitting cylinder portion 31A is formed with protruding portions 35 that protrude toward the seal ring portion 4A in the axial center X direction at a plurality of locations in the circumferential direction and can come into contact with the side wall 19a of the annular main portion 19. Due to the presence of the protruding portion 35, a longitudinal flow path 15 A is formed between the inner peripheral side peripheral surface 31 b which is the base end surface of the protruding portion 35 in the support cylinder portion 31 B in the axial center X direction. Further, the support cylinder part 31B, that is, the stationary sealing ring 4 is prevented from being rotated by the fitting structure of the pin part 31p protruding from the support cylinder part 31B in the axial center X direction and the hole part 3k of the inward flange 3F. It has been done.

第２支持輪３２は、Ｏリング３４を伴う嵌合筒部３１Ａ及びＯリング３６を伴う環状主部１９に外嵌し、かつ、一対のＯリング１０，１１を伴ってハウジング３に内嵌する環状部材である。第２支持輪３２の軸心Ｘ方向での中間部には、ハウジング３に形成されている液路３Ｗと径方向流路１５Ａとを連通する一又は複数の径方向貫通孔、即ち取込口１４が形成されている。つまり、静止密封輪４として、シール部Ｓを生むためのシール機能はシール輪部４Ａが担い、シール部Ｓを生じさせるための弾性機構５の付勢力を受止める機能は第１支持輪３１が担い、ハウジング３に内嵌支持する支持機能及びシール流体ｆを漏れなく取り込む機能は第２支持輪３２が担う、という機能別の３部品から静止密封輪４が構成されている。 The second support wheel 32 is externally fitted to the fitting cylinder portion 31 A with the O-ring 34 and the annular main portion 19 with the O-ring 36, and is fitted to the housing 3 with the pair of O-rings 10 and 11. An annular member. One or a plurality of radial through-holes, that is, intake ports, that communicate the liquid passage 3W formed in the housing 3 and the radial flow passage 15A at the intermediate portion in the axial center X direction of the second support wheel 32 14 is formed. That is, as the stationary sealing ring 4, the sealing ring part 4 A has a sealing function for generating the sealing part S, and the first supporting ring 31 has a function of receiving the urging force of the elastic mechanism 5 for generating the sealing part S. The stationary sealing ring 4 is composed of three parts according to function that the second supporting ring 32 bears the supporting function for supporting the inner fitting in the housing 3 and the function of taking in the sealing fluid f without leakage.

シール輪部４Ａは、自己浸透性を有するＳｉＣ摺動材で形成されている。ＳｉＣ摺動材の材料であるＳｉＣは通常の焼結体であり、焼結温度や成形面圧等で低密度化を実現させ、かつ、自己潤滑材は配合していないので、低密度でもメカニカルシールＭに必要となる性能を満足する硬度や強度を有している。このＳｉＣ摺動材の製造方法は、図７に示すように、ＳｉＣ粉末とメタノールとを混ぜる混合工程ａ、混合工程ａによる混合液を噴霧乾燥させて造粒材を作成する造粒工程ｂ、造粒工程ｂによる造粒材を型に入れてプレス成形することで環状の成形体を作成する成形工程ｃ、成形工程ｃによる成形体を所定高温のアルゴン雰囲気中で焼成させて炭化珪素焼結体を作成する焼成工程ｄ、とを有して成る。 The seal ring portion 4A is formed of a SiC sliding material having self-penetration. SiC, which is the material of the SiC sliding material, is a normal sintered body, which realizes low density due to the sintering temperature, molding surface pressure, etc., and does not contain a self-lubricating material. It has hardness and strength that satisfy the performance required for the seal M. As shown in FIG. 7, the manufacturing method of this SiC sliding material includes a mixing step a in which SiC powder and methanol are mixed, a granulating step b in which a mixture is spray-dried to create a granulated material, A granulated material obtained by the granulating step b is put into a mold and press-molded to form an annular shaped body, and the shaped body obtained by the forming step c is fired in a predetermined high-temperature argon atmosphere to sinter silicon carbide. And a firing step d for creating a body.

上述の製造方法によって得られた炭化珪素焼結体、即ち焼成工程ｄによる炭化珪素焼結体の一端面（一方の側周面）又は両端面を表面研磨してシール用の密封環を作成する仕上げ工程ｅを経ることにより、前述のシール輪部４Ａが作成される。つまり、図７に示すように、メカニカルシール用摺動材の製造方法に、焼成工程による炭化珪素焼結体の一端面を表面研磨する仕上げ工程ｅを追加することにより、メカニカルシール用静止密封環４におけるシール輪部４Ａの製造方法として定義することができる。 A silicon carbide sintered body obtained by the above-described manufacturing method, that is, one end surface (one side peripheral surface) or both end surfaces of the silicon carbide sintered body by the firing step d is polished to create a sealing ring for sealing. By passing through the finishing step e, the aforementioned seal ring portion 4A is created. That is, as shown in FIG. 7, by adding a finishing step e for polishing the one end surface of the silicon carbide sintered body by the firing step to the method for manufacturing the sliding material for mechanical seal, the stationary seal ring for mechanical seal is added. 4 can be defined as a manufacturing method of the seal ring portion 4A.

シール輪部４Ａの製造方法について詳述する。まず、混合工程ａは、粒子径約１．０μｍのα−ＳｉＣ粉末或いはβ−ＳｉＣ粉末１００ｇに、焼結助材としてのＢ４Ｃ粉末０．５ｇ及びカーボン源としてのフェノール樹脂４ｇを添加し、さらに成形助材としてＰＥＧ（ポリエチレングリコール）２９ｇ及びステアリン酸１ｇを添加して、これらを溶剤であるメタノールと共にボールミルで２４時間混合する、という工程である。 A manufacturing method of the seal ring portion 4A will be described in detail. First, the mixing step a is performed by adding 0.5 g of B4C powder as a sintering aid and 4 g of phenol resin as a carbon source to 100 g of α-SiC powder or β-SiC powder having a particle size of about 1.0 μm, In this process, 29 g of PEG (polyethylene glycol) and 1 g of stearic acid are added as molding aids, and these are mixed with methanol as a solvent in a ball mill for 24 hours.

造粒工程ｂは、混合工程ａで得られた混合液（流動性懸濁液）を、スプレードライヤーにより噴霧乾燥させることによって造粒し、径３０〜１００μｍの球形状の造粒材を得る、という工程である。成形工程ｃは、造粒工程ｂで得られた硬質の造粒材を所定の金型に充填してから、冷間プレス成形（成形圧：１００ＭＰａ）を行って環状形態を為す成形体を得る、という工程である。 The granulation step b is granulated by spray-drying the liquid mixture (fluid suspension) obtained in the mixing step a with a spray dryer to obtain a spherical granulated material having a diameter of 30 to 100 μm. It is a process. In the molding step c, the hard granulated material obtained in the granulation step b is filled in a predetermined mold, and then cold press molding (molding pressure: 100 MPa) is performed to obtain a molded body having an annular shape. This is the process.

焼成工程ｄは、成形工程ｃで得られた成形体を、加圧することなく１８５０〜２０５０℃のアルゴン雰囲気中で焼成させて炭化珪素焼結体を得る、という工程であり、この焼成工程ｄを経て作成される環状のものがメカニカルシール用摺動材である。そして、仕上げ工程ｅは、焼成工程ｄで得られた炭化珪素焼結体の一端面をＲａ＝０．０５〜０．２５の鏡面に表面研磨（ラップ）する等により密封環を得る、という工程である。ここで言う「密封環」とは回転密封環としても、又静止密封環としても使用可能な環のことであり、本発明においてはその密封環を「静止密封環４のシール輪部４Ａ」として使用している。尚、シール輪部４Ａの鏡面部分はシール面４ａ（密封端面）として機能する。 The firing step d is a step of firing the molded body obtained in the molding step c in an argon atmosphere at 1850 to 2050 ° C. without applying pressure to obtain a silicon carbide sintered body. The annular material created through this is a sliding material for mechanical seal. And the finishing step e is a step of obtaining a sealing ring by surface polishing (wrapping) one end surface of the silicon carbide sintered body obtained in the firing step d to a mirror surface of Ra = 0.05 to 0.25. It is. The “sealing ring” mentioned here is a ring that can be used as both a rotary sealing ring and a stationary sealing ring. In the present invention, the sealing ring is referred to as a “sealing ring portion 4A of the stationary sealing ring 4”. I use it. The mirror surface portion of the seal ring portion 4A functions as a seal surface 4a (sealed end surface).

上記製造方法によって得られる密封環、即ち実施例１〜実施例４の密封環の密度、気孔率、曲げ強度、硬度等の各種特性表を図４に示す。密度は水置換法により計測し、炭化珪素（ＳｉＣ）の理論密度を３．２ｇ／ｃｍ³ として気孔率を計算してある。一例として実施例１の気孔率Ｋ１は、Ｋ１＝１−（摺動材の測定密度）／（理論密度）＝（１−２．６０５／３．２）×１００＝１８．６（％）である。尚、図４の特性表に示すように、上記諸条件の範囲外である比較例１〜比較例４の密封環も作成し、その特性を確認してある。 FIG. 4 shows various characteristic tables such as density, porosity, bending strength, and hardness of the seal ring obtained by the above manufacturing method, that is, the seal rings of Examples 1 to 4. The density was measured by a water displacement method, and the porosity was calculated by setting the theoretical density of silicon carbide (SiC) to 3.2 g / cm ³ . As an example, the porosity K1 of Example 1 is K1 = 1− (measured density of sliding material) / (theoretical density) = (1-2.605 / 3.2) × 100 = 18.6 (%). is there. In addition, as shown in the characteristic table of FIG. 4, the sealing rings of Comparative Examples 1 to 4 which are outside the range of the above conditions were also prepared, and the characteristics were confirmed.

そして、本発明による密封環、即ちシール輪部４Ａと、例えばカーボン製の回転密封環２とを組み込んだメカニカルシール（図１に示すメカニカルシールＭ）を使用して工業用水によるシール試験を行い、密封環の性能及びシール性能を確認した。また、静止密封環４のシール輪部４Ａとして使用する密封環の自己浸透性を測定するために、図２に示すような実験装置Ａを作成し、その実験装置Ａによる測定値も、図４に示す特性表に記載することとした。 Then, a seal test with industrial water is performed using a mechanical seal (mechanical seal M shown in FIG. 1) incorporating a seal ring according to the present invention, that is, a seal ring portion 4A and a rotating seal ring 2 made of carbon, for example. The performance of the sealing ring and the sealing performance were confirmed. Further, in order to measure the self-permeability of the seal ring used as the seal ring portion 4A of the stationary seal ring 4, an experimental apparatus A as shown in FIG. 2 is created, and the measured values by the experimental apparatus A are also shown in FIG. It was decided to be described in the characteristic table shown in.

図１に示すメカニカルシールＭを用いての摺動テストの条件は、回転密封環２と静止密封環４とによるシール部Ｓの径＝４０ｍｍ（アンバランス型）、回転速度＝３６００回転／分、フラッシング流量＝３リットル／分、試験用液体＝工業用水、運転時間＝１００時間、液体温度＝３０℃、圧力＝２．５ＭＰａである。尚、摺動テスト結果（図４の「摺動特性」※）における◎、○、△、×の意味は下記のようである。
◎：回転密封環２及びシール輪部４Ａ（静止密封環４）共に摩耗が検出できず
○：単位時間当たりの摩耗量が、回転密封環２が０．０１μｍ／ｈｒ以下、かつ、シール輪部４Ａ（静止密封輪４）が０．１μｍ／ｈｒ以下
△：単位時間当たりの摩耗量が、回転密封環２が０．０１μｍ／ｈｒ以下、かつ、シール輪部４Ａ（静止密封輪４）が０．１μｍ／ｈｒ以上
×：回転密封環２の単位時間当たりの摩耗量が０．０１μｍ／ｈｒ以上 The condition of the sliding test using the mechanical seal M shown in FIG. 1 is that the diameter of the seal portion S by the rotating seal ring 2 and the stationary seal ring 4 = 40 mm (unbalanced type), the rotation speed = 3600 rotations / minute, Flushing flow rate = 3 liters / minute, test liquid = industrial water, operation time = 100 hours, liquid temperature = 30 ° C., pressure = 2.5 MPa. In the sliding test results (“sliding characteristics” * in FIG. 4), the meanings of “」 ”,“ ◯ ”,“ Δ ”, and“ X ”are as follows.
◎: Wear is not detected in both the rotary seal ring 2 and the seal ring portion 4A (stationary seal ring 4). ○: The amount of wear per unit time is 0.01 μm / hr or less for the rotary seal ring 2 and the seal ring portion. 4A (stationary sealing ring 4) is 0.1 μm / hr or less Δ: Wear amount per unit time is 0.01 μm / hr or less for the rotary sealing ring 2 and the sealing ring portion 4A (stationary sealing ring 4) is 0 .1 μm / hr or more x: Wear amount per unit time of the rotary seal ring 2 is 0.01 μm / hr or more

次に、自己浸透性の実験装置Ａについて説明する。図２，図３に示すように、実験装置Ａは、略ドーナツ状のシール輪部４Ａ（密封環）が装填される円形凹入部２３を有する実験ケース本体２１と、円形凹入部２３に内嵌されてその上面をカバーする状態で実験ケース本体２１の上面に複数のボルト２４で固定される蓋ケース２２と、から成る実験器２０を有して構成されている。実験ケース本体２１には、円形凹入部２３に装填されている回転密封環２の外周面２ｂのほぼ全面に開口する環状凹入部２５、及び環状凹入部２５に連通する入口路２６が形成されている。蓋ケース２２の中央部には、漏れ出た液体を測定するための円形の大径口２２Ａが形成されている。尚、２７、２８はＯリングである。 Next, the self-penetrating experimental apparatus A will be described. As shown in FIGS. 2 and 3, the experimental apparatus A includes an experimental case main body 21 having a circular recessed portion 23 in which a substantially donut-shaped sealing ring portion 4 A (sealing ring) is loaded, and an internal fit in the circular recessed portion 23. The experimenter 20 includes a lid case 22 fixed to the upper surface of the experiment case main body 21 with a plurality of bolts 24 in a state of covering the upper surface. The experiment case main body 21 is formed with an annular recess 25 that opens to almost the entire outer peripheral surface 2 b of the rotary seal ring 2 loaded in the circular recess 23, and an inlet passage 26 that communicates with the annular recess 25. Yes. A circular large-diameter port 22 A for measuring the leaked liquid is formed at the center of the lid case 22. Reference numerals 27 and 28 denote O-rings.

実験装置Ａによるシール輪部４Ａの実験方法は、円形凹入部２３にシール輪部４Ａを配置して蓋ケース２２で蓋をした実験状態（図２参照）において、実験ケース本体２１の側面２１Ａに開口する入口路２６から正圧を有する試験液ｒを供給し、図３に示すように環状凹入部２５に満たす。その実験液ｅで環状凹入部２５が満たされている状態を所定時間維持し、静止密封環４の内周面４ｃから漏れ出た試験液ｒの量を測定するのである。尚、実験条件の一例は、試験液ｒとして、温度３０℃で２．５ＭＰａの圧が掛けられた工業用水であり、シール輪部４Ａのサイズ例は、外径×内径×厚さがφ５４×φ４０×６（単位：ｍｍ）である。 The experiment method of the seal ring portion 4A by the experimental apparatus A is as follows. In the experimental state (see FIG. 2) in which the seal ring portion 4A is disposed in the circular recessed portion 23 and covered with the lid case 22 (see FIG. 2). A test solution r having a positive pressure is supplied from the opening inlet passage 26 and fills the annular recess 25 as shown in FIG. The state in which the annular recess 25 is filled with the experimental liquid e is maintained for a predetermined time, and the amount of the test liquid r leaking from the inner peripheral surface 4c of the stationary seal ring 4 is measured. An example of the experimental conditions is industrial water applied with a pressure of 2.5 MPa at a temperature of 30 ° C. as the test solution r, and an example of the size of the seal ring portion 4A is an outer diameter × inner diameter × thickness of φ54 ×. φ40 × 6 (unit: mm).

図４の特性表における「自己浸透性」は、目視で漏れが確認できたとき（図３参照）から計測し始めた（シール輪部４Ａの内周面４ｃから滲み出てきた液体を測定する）。また、「自己浸透性」における×とは、「２４ｈｒ（時間）計測しても目視で漏れが確認できなかったこと」を意味している。図４（ａ）は、焼成温度を１８００℃〜２２００℃超の範囲で種々に変更設定した場合の各種特性を示し、図４（ｂ）は、図４（ａ）における摺動特性が合格（評価が○と◎）である実施例１〜４について、気孔率と浸透漏れ量（自己浸透性）とを計測したものである。 “Self-permeability” in the characteristic table of FIG. 4 starts to be measured when leakage can be visually confirmed (see FIG. 3) (measures the liquid that has oozed out from the inner peripheral surface 4c of the seal ring portion 4A). ). In addition, “x” in “self-penetration” means “a leak could not be visually confirmed even when measured for 24 hours (hours)”. FIG. 4A shows various characteristics when the firing temperature is variously changed in the range of 1800 ° C. to over 2200 ° C., and FIG. 4B shows that the sliding characteristics in FIG. About Examples 1-4 whose evaluation is (circle) and (double-circle)), a porosity and the amount of osmotic leakage (self-permeability) are measured.

比較例１のものは、自己浸透性はあったが、焼結密度が低いためか強度、硬度が低く、また摩耗量も多く（摺動特性は×）、メカニカルシールとしての特性は不十分である。比較例２〜４のものは、強度や硬度はあり、また摺動特性の評価が○のもの（比較例２）もあったが、いずれも自己浸透性が無かったため摺動面の面荒れが発生し、摩耗も認められた。比較例３のものは、従来の高密度化ＳｉＣ製であり、ＳｉＣ摺動材（メカニカルシール用密封環）として一般的に使用されているものである。試験用のメカニカルシールＭはその従来品に関する選定基準をはるかに超える負荷条件であるが故に、比較例３のものには摩耗、面荒れが発生し、当然ながら不合格である。 Comparative Example 1 had self-penetration, but due to its low sintered density, its strength and hardness were low, and the amount of wear was large (sliding property was x), and the properties as a mechanical seal were insufficient. is there. The comparative examples 2 to 4 have strength and hardness, and there were also those with good sliding characteristics (comparative example 2) (comparative example 2). Occurred and wear was also observed. The thing of the comparative example 3 is a product made from the conventional high density SiC, and is generally used as a SiC sliding material (sealing ring for mechanical seals). Since the test mechanical seal M is under a load condition that far exceeds the selection criteria for the conventional product, the comparative example 3 suffers from wear and surface roughness, and of course is rejected.

実験結果による図４（ａ）の特性表から、ＳｉＣ摺動材製のメカニカルシール用密封環（シール輪部４Ａ）は、焼成温度が１８５０℃〜２０５０℃で、焼結密度が２．６ｇ／ｃｍ³ 〜３．０ｇ／ｃｍ³ で、強度が４００ＭＰａ以上、硬度が１６００Ｈｖ以上のＳｉＣ焼結体であることが分かる。そして、その場合のＳｉＣ焼結体においては、外周面Ｗｂから内周面Ｗｃに向けての単位時間当りの液体の浸透漏れ量Ｆは０．０１ｍｌ／２４ｈｒ≦Ｆ≦５００ｍｌ／１ｈｒの範囲である。このようなメカニカルシール用密封環では、図１に示すメカニカルシールＭにおける前述の過負荷条件においても良好なメカニカルシール機能が発揮される。尚、参考として、実施例１〜４のＳｉＣ摺動材（シール輪部４Ａ）における気孔率と浸透漏れ量（自己浸透性）を図４（ｂ）に示す。また、実施例１，４、及び比較例１，２，４の各ＳｉＣ摺動材の表面状況写真を図５（ａ），（ｂ）及び図６（ａ），（ｂ），（ｃ）に示す。 From the characteristic table of FIG. 4A based on the experimental results, the sealing ring for the mechanical seal made of SiC sliding material (seal ring part 4A) has a firing temperature of 1850 ° C. to 2050 ° C. and a sintered density of 2.6 g / It can be seen that the SiC sintered body has a strength of 400 MPa or more and a hardness of 1600 Hv or more at cm ^{3 to} 3.0 g / cm ³ . In the SiC sintered body in that case, the permeation leakage amount F per unit time from the outer peripheral surface Wb to the inner peripheral surface Wc is in the range of 0.01 ml / 24 hr ≦ F ≦ 500 ml / 1 hr. . In such a seal ring for mechanical seal, a good mechanical seal function is exhibited even under the above-described overload condition in the mechanical seal M shown in FIG. For reference, the porosity and permeation leakage amount (self-permeability) in the SiC sliding materials (seal ring portion 4A) of Examples 1 to 4 are shown in FIG. Moreover, the surface condition photograph of each SiC sliding material of Examples 1, 4 and Comparative Examples 1, 2, 4 is shown in FIGS. 5 (a), (b) and FIGS. 6 (a), (b), (c). Shown in

ところで、前記浸透漏れ量Ｆが規定の範囲（０．０１ｍｌ／２４ｈｒ≦Ｆ≦５００ｍｌ／１ｈｒ）であることの確認を実験装置Ａで行うに当り、メカニカルシール用密封環そのものでは不可のときがある。即ち、メカニカルシールが異なれば回転及び静止の各密封環の寸法（サイズ）も種々に異なることが多いので、実験装置Ａの寸法に合わないことがあるからである。そのような場合には、密封環を所定の規格寸法に加工（切削等）して環状体(図示省略)を作成し、その規格寸法に加工された環状体を用いることで実験装置Ａによる漏れ量測定が可能になる。規格寸法の例としては、前述の「外径×内径×厚さがφ５４×φ４０×６（単位：ｍｍ）」が挙げられるが、その他でも良い。尚、所定の規格寸法より密封環が小さい場合には、計算によって規格寸法に合せた換算値でも良い。 By the way, when the experiment apparatus A confirms that the permeation leakage amount F is within a specified range (0.01 ml / 24 hr ≦ F ≦ 500 ml / 1 hr), the mechanical seal seal ring itself may not be possible. . That is, if the mechanical seals are different, the sizes (sizes) of the rotating and stationary sealing rings are often different, and therefore may not match the dimensions of the experimental apparatus A. In such a case, an annular body (not shown) is created by machining (cutting, etc.) the sealing ring to a predetermined standard dimension, and leakage by the experimental apparatus A is performed by using the annular body machined to the standard dimension. Quantity measurement is possible. As an example of the standard dimension, the above-mentioned “outer diameter × inner diameter × thickness is φ54 × φ40 × 6 (unit: mm)” may be mentioned, but other dimensions may be used. If the seal ring is smaller than a predetermined standard dimension, a converted value matched to the standard dimension by calculation may be used.

本発明による自己浸透性を有するＳｉＣ摺動材製のシール輪部４Ａ（メカニカルシール用密封環）は、数μｍの不連続気孔及び連続気孔を有しており、十分な強度と硬度を有しながら、ある程度の液体圧をかけると液体が摺動材内部まで浸透する。故に、浸透によって程よく濡れている状態が維持できることから、摺動面は常に液体雰囲気になり、メカニカルシールや軸受け等の起動時に発生するドライ状況が改善され、円滑に起動することが可能になる。また、運転中においても液体が摺動面に常に内部から送り出されているので、安定した液体膜が形成され続けてシール特性を良好に保つことができる。そして、浸透した液体が大気側で溜まることでクエンチ効果が得られるという利点もある。 The seal ring portion 4A (sealing ring for mechanical seal) made of a SiC sliding material having self-penetration according to the present invention has discontinuous pores and continuous pores of several μm, and has sufficient strength and hardness. However, when a certain amount of liquid pressure is applied, the liquid penetrates into the sliding material. Therefore, since the moderately wet state can be maintained by the permeation, the sliding surface is always in a liquid atmosphere, and the dry condition that occurs when starting the mechanical seal, the bearing, and the like is improved, and the start can be performed smoothly. In addition, since the liquid is always sent from the inside to the sliding surface even during operation, a stable liquid film can be continuously formed and the sealing characteristics can be kept good. And there exists an advantage that the quenching effect is acquired because the penetrated liquid accumulates on the atmosphere side.

さて、図１に示すように、静止密封環４には、ハウジング３に形成されている液路３Ｗを介して供給されてくる冷却水（シール用液体の一例）ｆを取り込むための取込口１４及びこれに続く行止り状の供給流路１５が形成されている。供給流路１５は、軸心Ｘに対する径方向に向く縦流路（径方向流路の一例）１５Ａと、軸心Ｘに沿う方向に向く横流路（軸心方向流路の一例）１５Ｂとを有し、シール部Ｓに貫通して回転密封環２のシール面２ａで閉塞される状態に構成されている。そして、前述したように、シール輪部４Ａのシール面４ａに、軸心Ｘに関する環状で、かつ、内部流路１５のシール面側開口部を含む状態の冷却水充填用の側周溝１６が形成されている。 As shown in FIG. 1, the stationary sealing ring 4 has an intake port for taking in cooling water (an example of a sealing liquid) f supplied via a liquid path 3W formed in the housing 3. 14 and the following dead-end supply flow path 15 are formed. The supply flow path 15 includes a longitudinal flow path (an example of a radial flow path) 15A facing in the radial direction with respect to the axial center X, and a lateral flow path (an example of the axial flow path) 15B facing in a direction along the axial center X. And is configured to penetrate through the seal portion S and be blocked by the seal surface 2a of the rotary seal ring 2. As described above, the side circumferential groove 16 for filling the cooling water in a state of being annular with respect to the axis X and including the opening on the seal surface side of the internal flow path 15 is formed on the seal surface 4a of the seal ring portion 4A. Is formed.

供給流路１５は、一部品としての静止密封輪4と見る場合には、取込口１４も縦流路１５Ａも横流路１５Ｂも内部流路であると言え、シール輪部４Ａと支持輪部４Ｂとの集合体と見る場合には、横流路１５Ｂは内部流路（シール輪部４Ａの内部に形成される）であるが、シール輪部４Ａと支持筒部３１Ｂとの間に形成される縦流路１５Ａは内部流路ではなく、言わば「間隙流路」であると言える。従って、本明細書においては、これら内部流路や間隙流路を総称して「供給流路」と呼ぶものとしている。 When the supply flow path 15 is viewed as a stationary sealing ring 4 as one component, it can be said that the intake port 14, the vertical flow path 15A, and the horizontal flow path 15B are internal flow paths. When viewed as an aggregate with 4B, the lateral flow path 15B is an internal flow path (formed inside the seal ring portion 4A), but is formed between the seal ring portion 4A and the support cylinder portion 31B. The vertical flow path 15A is not an internal flow path but can be said to be a “gap flow path”. Therefore, in this specification, these internal flow paths and gap flow paths are collectively referred to as “supply flow paths”.

自己浸透性を有するＳｉＣ摺動材製のシール輪部４Ａに内部流路である横流路１５Ｂが形成されているから、冷却水ｆが浸透してシール面４ａに迅速に及ぶようになり、供給流路１５が形成されていないものに比べて、冷却水ｆの供給開始から実際に静止密封環４のシール面４ａに及ぶまでの応答時間が短縮化される。つまり応答性が良くなる。そして、横流路１５Ｂがシール輪部４Ａを貫通して回転密封環２のシール面２ａで閉塞される構造とすることで応答性がより良くなるとともに、側周溝１６を設けることで一層応答性が改善されるという利点がある。 Since the transverse flow path 15B, which is an internal flow path, is formed in the seal ring portion 4A made of a SiC sliding material having self-permeability, the cooling water f permeates and quickly reaches the seal surface 4a. Compared with the case where the flow path 15 is not formed, the response time from the start of the supply of the cooling water f to the actual seal surface 4a of the stationary seal ring 4 is shortened. That is, responsiveness is improved. The lateral flow path 15B penetrates the seal ring portion 4A and is closed by the sealing surface 2a of the rotary seal ring 2. The responsiveness is further improved, and the side circumferential groove 16 is provided to further increase the responsiveness. There is an advantage that is improved.

〔実施例２〕
図８に示すように、静止密封環４がＳｉＣ摺動材製のシール輪部４Ａと支持輪部４Ｂとの２部品で成る構造を持つメカニカルシールＭでも良い。図１に示す実施例１のメカニカルシールＭと比較した場合、シール輪部４Ａはほぼ同じ形状のものであり、支持輪部４Ｂは、静止密封環４としての断面が略矩形形状を呈するようにシール輪部４Ａの大気側外周部を補填するような小部品に形成されている。従って、図１に示すメカニカルシールＭと同じ部位や同じ機能を有する箇所には同じ符号を付してその説明が為されたものとする。 [Example 2]
As shown in FIG. 8, the stationary seal ring 4 may be a mechanical seal M having a structure composed of two parts of a seal ring portion 4A made of SiC sliding material and a support ring portion 4B. When compared with the mechanical seal M of Example 1 shown in FIG. 1, the seal ring portion 4A has substantially the same shape, and the support ring portion 4B has a substantially rectangular cross section as the stationary seal ring 4 It is formed in a small part that fills the atmosphere side outer periphery of the seal ring portion 4A. Therefore, it is assumed that the same parts as the mechanical seal M shown in FIG.

この場合、図１における一対のＯリング３４，３６が省略されており、ハウジング３は第１ハウジング３Ａと第２ハウジング３Ｂとで成っている。対ハウジング用のＯリング１１は、第１及び第２ハウジング３Ａ，３Ｂどうしのシールも兼ねるものとなっており、もう一つのハウジング用のＯリング１０は、支持輪部４Ｂに伝わる弾性機構５の付勢力を第２ハウジング３Ｂに伝えるための部材にもなっている。 In this case, the pair of O-rings 34 and 36 in FIG. 1 is omitted, and the housing 3 includes a first housing 3A and a second housing 3B. The O-ring 11 for the housing also serves as a seal between the first and second housings 3A and 3B, and the other O-ring 10 for the housing is an elastic mechanism 5 that is transmitted to the support wheel portion 4B. It is also a member for transmitting the urging force to the second housing 3B.

〔別実施例〕
横流路１５Ｂは、静止側シール面４aに届かずに行止り状となるもの（図１の仮想線の部分参照）でも良い。また、シール用流体は、冷却水（冷却液）のほか、クエンチング液、フラッシング液、潤滑液等の種々のものを含む概念である。 [Another Example]
The lateral flow path 15B may be a dead end without reaching the stationary seal surface 4a (see the phantom line in FIG. 1). Further, the sealing fluid is a concept including various types such as a quenching liquid, a flushing liquid, and a lubricating liquid in addition to the cooling water (cooling liquid).

１回転軸
２回転密封環
２ａ回転側シール面
３ハウジング
４静止密封環
４Ａシール輪部
４Ｂ支持輪部
４ａ静止側シール面
４ｂ外周面
５弾性機構
１４取込口
１５供給流路
１５Ａ径方向流路
１５Ｂ軸心方向流路、内部流路
３１第１支持輪
３２第２支持輪
Ｆ浸透漏れ量
Ｓシール部
Ｘ軸心
ｆシール用液体 DESCRIPTION OF SYMBOLS 1 Rotating shaft 2 Rotating sealing ring 2a Rotating side sealing surface 3 Housing 4 Static sealing ring 4A Sealing ring part 4B Supporting ring part 4a Static side sealing surface 4b Outer peripheral surface 5 Elastic mechanism 14 Intake port 15 Supply channel 15A Radial direction channel 15B Axial direction flow path, internal flow path 31 1st support ring 32 2nd support ring F Permeation leak amount S Seal part X Shaft center f Seal liquid

Claims

A rotary seal ring that is supported relative to the rotary shaft so as not to rotate relative to the rotary shaft; a stationary seal ring that is supported relative to the housing so as not to rotate relative thereto; a rotary seal surface of the rotary seal ring; and a static seal surface of the static seal ring. A mechanical seal having an elastic mechanism for forming a seal portion by pressing each other in the axial direction of the rotation shaft,
The stationary seal ring is composed of a seal ring portion having the stationary-side seal surface, and a support ring portion that supports the seal ring portion and is supported by the housing so as not to be relatively rotatable.
The sealing ring portion has a permeation leakage amount F of liquid per unit time from the outer peripheral surface to the inner peripheral surface of the annular body formed by processing this into a predetermined standard dimension.
0.01ml / 24hr ≦ F ≦ 500ml / 1hr
And is formed of a SiC sliding material defined in
A mechanical seal in which a supply flow path for introducing a sealing liquid supplied through the housing into the seal ring portion is formed.

2. The mechanical seal according to claim 1, wherein the supply flow path is formed in an open front end internal flow path that penetrates the seal portion and is closed by the rotation-side seal surface.

A first support wheel disposed between the housing and the seal wheel part in the axial direction so as to receive an urging force by the elastic mechanism; And a second support wheel that is fitted on both the seal wheel part and the first wheel part and includes a suction port to which a sealing fluid is supplied from the housing. The mechanical seal according to 1 or 2.

The supply flow path is formed between the seal ring portion and the first support ring in the axial direction and communicates with the intake port; and a radially inner end of the radial flow path The mechanical seal according to claim 3, further comprising an axial flow path that communicates with a portion and extends toward the stationary seal surface.

2. The mechanical seal according to claim 1, wherein the supply flow path is formed in a dead end shape whose end is located inside the seal ring portion.