CN1051227A - 用于柱塞型阀门的对中及密封环回缩装置 - Google Patents
用于柱塞型阀门的对中及密封环回缩装置 Download PDFInfo
- Publication number
- CN1051227A CN1051227A CN90108618A CN90108618A CN1051227A CN 1051227 A CN1051227 A CN 1051227A CN 90108618 A CN90108618 A CN 90108618A CN 90108618 A CN90108618 A CN 90108618A CN 1051227 A CN1051227 A CN 1051227A
- Authority
- CN
- China
- Prior art keywords
- ring
- groove
- spool
- valve
- mentioned
- 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
- 230000006872 improvement Effects 0.000 description 5
- 238000007789 sealing Methods 0.000 description 4
- 210000002421 cell wall Anatomy 0.000 description 2
- 230000000295 complement effect Effects 0.000 description 2
- 239000012467 final product Substances 0.000 description 2
- 230000000712 assembly Effects 0.000 description 1
- 238000000429 assembly Methods 0.000 description 1
- 230000015572 biosynthetic process Effects 0.000 description 1
- 230000008859 change Effects 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000008030 elimination Effects 0.000 description 1
- 238000003379 elimination reaction Methods 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000000034 method Methods 0.000 description 1
- 230000000737 periodic effect Effects 0.000 description 1
- 238000010248 power generation Methods 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 1
Images
Classifications
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
- F16K3/00—Gate valves or sliding valves, i.e. cut-off apparatus with closing members having a sliding movement along the seat for opening and closing
- F16K3/22—Gate valves or sliding valves, i.e. cut-off apparatus with closing members having a sliding movement along the seat for opening and closing with sealing faces shaped as surfaces of solids of revolution
- F16K3/24—Gate valves or sliding valves, i.e. cut-off apparatus with closing members having a sliding movement along the seat for opening and closing with sealing faces shaped as surfaces of solids of revolution with cylindrical valve members
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16J—PISTONS; CYLINDERS; SEALINGS
- F16J9/00—Piston-rings, e.g. non-metallic piston-rings, seats therefor; Ring sealings of similar construction
- F16J9/12—Details
- F16J9/22—Rings for preventing wear of grooves or like seatings
-
- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16K—VALVES; TAPS; COCKS; ACTUATING-FLOATS; DEVICES FOR VENTING OR AERATING
- F16K3/00—Gate valves or sliding valves, i.e. cut-off apparatus with closing members having a sliding movement along the seat for opening and closing
- F16K3/22—Gate valves or sliding valves, i.e. cut-off apparatus with closing members having a sliding movement along the seat for opening and closing with sealing faces shaped as surfaces of solids of revolution
- F16K3/24—Gate valves or sliding valves, i.e. cut-off apparatus with closing members having a sliding movement along the seat for opening and closing with sealing faces shaped as surfaces of solids of revolution with cylindrical valve members
- F16K3/243—Packings
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y10—TECHNICAL SUBJECTS COVERED BY FORMER USPC
- Y10T—TECHNICAL SUBJECTS COVERED BY FORMER US CLASSIFICATION
- Y10T137/00—Fluid handling
- Y10T137/8593—Systems
- Y10T137/86493—Multi-way valve unit
- Y10T137/86718—Dividing into parallel flow paths with recombining
- Y10T137/86759—Reciprocating
- Y10T137/86791—Piston
Landscapes
- Engineering & Computer Science (AREA)
- General Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Control Of Turbines (AREA)
- Lift Valve (AREA)
- Sliding Valves (AREA)
- Quick-Acting Or Multi-Walled Pipe Joints (AREA)
- Automatic Assembly (AREA)
Abstract
用于蒸汽节流阀上的阀芯组件包括一个阀体和
一个安装在阀体一端并可拆卸的导向环,导向环和阀
体共同形成一个圆周槽,该槽的一个侧壁上另开有一
个***磨损环的槽。磨损环有一个紧靠在压力密封
环上的支撑面,当阀芯突然动作时,会相应地在压力
密封环上产生某些回缩。
Description
本发明与用于蒸汽透平的蒸汽控制阀有关,尤其是与蒸汽节流阀中所用的改进压力密封环有关。
电力公用事业发电***中一般都有由透平驱动的交流发电机,而某些***用水力透平,大多数***则用蒸汽透平,在用蒸汽透平的***中,被控制流过透平的蒸汽流量调整驱动透平轴的转速,蒸汽流量随着对发电机的电功率需要量而进行控制,于是发电机产生的交流电频率保持恒定值,而与加给发电机的电力需要量的变化无关。蒸汽流量又受诸如节流阀和蒸汽傍通阀等各种流量控制阀调整。
本发明涉及到蒸汽透平流量控制阀,特别是节流阀的一项改进。过去,这些阀门都有一个装在阀罩圆柱筒内的阀芯,阀芯中有一条或几条压力密封环的槽。压力密封环能维持环前后的压力降,此压力降使压力密封环与阀芯接触。在运行时常常见到在阀芯沿着压力密封环槽边缘的接触表面被压力密封环磨出一个台阶,沿着槽边磨出的这个台阶会导致压力密封环嵌在阀芯和阀罩圆筒内腔之间,并导致当要求蒸汽透平实现超速保护时,该阀失去关闭能力。本发明的目的就是当压力密封环磨进阀芯上的密封槽壁的时候,防止压力密封环嵌入阀芯和阀罩圆筒内腔之间。
典型的节流阀和蒸汽旁通阀可见于先前授予Heymann《消声节流阀》的美国专利(№ 3,857,542)和授予Brown等人《蒸汽透平控制阀的结构》的美国专利(№3,602,261)以及授予Dawawala等人《周期性负载的蒸汽透平控制阀》的美国专利(№4,679,769)。后一个专利给出一种整体阀罩的控制阀的总体结构。这些专利全部转让给西屋电气公司。
阀芯在阀罩圆柱腔内的导向,流行的做法是由邻近阀芯上、下端处的间隙和压力密封环完成;阀杆与阀芯间是球窝式联接,在圆柱腔内实现铰接。横向的或沿着轨道运动的阻力只局限于球窝联接处的摩擦和压力密封环与相关的阀芯槽之间的阻滞摩擦。
最近,已经开发了一种设有压力密封环的节流阀,密封环置于阀芯周围的密封槽中,该槽有一个在槽的底表面相邻的一个槽壁处形成的减载槽;减载槽使密封槽的一个壁表面的宽度减小到比密封环的宽度要窄。这样,该窄的承载表面至少可以均匀地磨损到减载槽的深度,从而减少密封环嵌入或卡死的机会。关于这个方案的说明在转让给西屋公司的美国专利(№S.N.298,443)中有所描述。在那个专利中所陈述的发明提供了一种减轻密封槽磨损的影响和减少密封环嵌入可能性的方法,本发明的目的在于提供一种防止密封卡死和减少密封表面磨损的结构。
出于这个目的,本发明所考虑的有:
圆锥形部份保证绝对对中(中心活动)并对阀芯上部产生阻滞,当要求阀芯突然关闭时,楔形物的形状将使密封环趋于缩回,从而不与圆柱腔衬套接触,这有利于关闭。
为了更好地理解本发明,可能还必须参考对以下有关附图所做的详细描述。在这些附图中:
图1是阀芯和阀罩的局部剖视图,描述了压力密封环围绕着阀芯延伸的圆周槽中定位;
图2是一张类似的阀芯剖视图,给出压力密封环对密封槽侧壁磨损的情况;
图3是阀罩的局部剖视图,包括一个通常在蒸汽控制阀中能见到的那种阀芯;
图4是阀芯的一部份的局部剖视,阀芯按照本发明设置在阀罩内侧。
参考图1和图2,这里示出按先有技术的蒸汽透平蒸汽控制阀或叫有阀罩的阀门10的局部。这种先有技术结构包括一个与活塞相似的阀芯11,它装在阀罩圆筒13的圆筒腔12中。压力密封环14设在圆周槽15内,围绕阀体或阀芯11的外表面19上延伸,并相对于阀罩圆筒腔12内壁17的一个邻近接触表面滑动。正常工作时,环形空间P1是高压侧,而在密封环14的另一侧有更高的压力P2。应用这个压差驱动密封环14紧靠在密封槽15的内壁面18上。槽15还有一底面20和与壁18相对的另一侧壁21。
P1和P2之间的压差在槽15的侧壁18的表面上保持一个压力,当台阶22被磨得足够深的时候(就像图2所表示的那样),环14有卡在沿其外径24阀芯上磨出的台阶23与阀罩圆柱腔12之间任何一个地方的趋势。因此台阶22能够导致压力密封如所示那样嵌入,当要求蒸汽透平实现超速保护时,阀门不能关闭。
如图1局部剖视图所示,阀芯11包括一个阀体25,在其上形成压力密封环槽15。在阀罩筒腔内阀体25由导向环27导向。导向环27是一个精密机加工的零件,由诸如螺钉29等联结件直接固定在阀体25上并使阀芯在阀罩圆筒体内定位。在导向环27与阀罩圆筒腔的内表面12之间设有间隙30以便让阀芯11在圆筒腔内滑动。这个间隙30是让阀芯在圆筒腔内移动所必须的。在邻近阀芯11下端36设有类似的间隙34以帮助阀芯在圆筒腔12内导向。
现在看图3。这里给出一个完整的阀芯组件的剖视图。阀芯11是一个圆杯形组件,在阀罩13内分别由上、下导向环27和31导向。导向环27和31用若干以29和33表示的螺钉固定在阀芯11的每一端。阀芯11通过轴35来操纵,借助球窝式联接,轴35耦合到阀芯下端在图中所注的37处。轴35在支持架39中滑动,该支持架有适当的密封,以防止来自阀芯上部泄漏的蒸汽通过轴35与支持架39之间的滑动界面处漏出。为更好地描述图3中示出的这种形式蒸汽阀门,可参考转让给本发明受让人的美国3857542号专利。
现在再来看图4。这是一个阀芯组件的局部剖视图,这里的阀芯是根据本发明制成的,用于图3所描述的那种形式的蒸汽节流阀。这个阀芯有一个在41处表示的圆周压力密封环槽,围绕着阀芯,和位于槽41内的压力密封环43。改进后的阀芯有一个加宽了的上导向环45,沿着通过或横切槽41的平面49与阀体47相接。最好该平面49落在阀体47的上表面46上。这样,密封槽41就由装上了上导向环45的圆周外缘部份而形成,这种结构由于可以沿着导向环45的外缘构成槽41,所以简化了制造程序。请注意,这种方案可以在固定上导向环45之前即把密封环43放在阀体47的顶部,以简化了将密封环安装在槽41的程序。再有,在拆卸或检查压力密封环43时,只需拆掉螺钉29和上导向环45即可,而不碰伤或毁坏密封环。
如图4所示,还可作进一步改进,即在上导向环45的一个内壁53上开出一条附加切口51,然后把一个磨损环55置于该切口51中,以提供一个支撑面垫在压力密封环的上支撑面上。磨损环55的外支撑面57最好用一个带向内斜度的或圆锥形的表面构成;同样地,压力密封环43与磨损环55的支撑表面57相接触的表面59也做成有角度的。壁面53可以比外表面63切得更深一些,或切削到邻近密封槽41底表面。这样,当磨损环55上的支撑表面逐渐磨掉的时候,可以有足够的空间容纳压力密封环43的内边缘65。
倾斜的或者有角度的支撑面57和59的好处之一是有利于有一个较大的接触面积,从而减小了接触压力。当阀芯向下运动时,加在密封环倾斜表面处的惯性作用引起密封环向内运动,即缩回,因此减小了阀罩上的压力。压力密封环上的减小了的压力可以使压力密封环使用更长的时间,从而延长了它们的寿命。磨损环55可以用合适的材料制成,以便在与压力密封环43的支撑表面59的接触中逐渐被磨掉,因为这些磨损环很容易更换,只需从阀芯组件上将上导向环45拆下来即可。
推荐用于压力密封环43和磨损环55的圆锥形斜面能使阀芯组件与阀的中心线更好地保持一致,从而增加阀芯在圆柱腔内运动的稳定性或阻力。上导向环与阀芯在密封槽处联结便于组装、拆卸和检查阀芯组件的各部件等多种作业。还有,这种圆锥斜面的设计,以致阀芯向下的运动在密封环上产生一个周向均匀的压力,加在组合密封环上的这个压力将使密封环从与圆筒腔的接触中缩回,于是增大了防止密封环在腔壁与阀门导向环槽之间卡死的裕度。
至此我们讲过的是一种蒸汽节流阀或有罩阀门,它包括一个装在阀罩或阀芯室内,并有密封槽的阀芯组件,密封槽用于容纳压力密封环。密封环槽包括一个在阀芯外表面上构成的环形槽,它有一对侧壁和一个底面。一种形式的改进,它包括一个切口,至少在密封环槽的一个侧壁、密封槽底面的中间部位和阀芯外表面构成,环状的磨损环置于该切口中并紧紧地、完全地环绕着阀芯延伸。磨损环径向高度大于槽深,以便磨损环至少可以有一个预留部份露出在密封槽侧壁之外-这里所说的侧壁即是构成切口的那面壁。磨损环最好做成圆锥斜面的或者有向内倾角的锥形支撑面;压力密封环装在该密封槽内,并且也有倾斜的圆锥形支撑面,其形状恰与磨损环上的支撑面相匹配;磨损环和密封环上的支撑面的角度的选择要使阀芯下行时,磨损环对密封环在圆周上施加均匀向内的压力。上导向环构成为阀芯的一个部件,并可拆装地与在导向环外缘处形成的压力密封槽相装配。在此处导向环与阀芯相匹配。这种结构可以通过简单地从阀体上拆掉导向环达到拆下磨损环进行更换的目的。同样,只需从阀体上拆掉上导向环即可无损伤地拆下和检查压力密封环。
尽管本发明叙述只考虑一个较佳实施例,但对那些精于本行技术的人来说,其它的改进、方案和布置是显而易见的,因此其意图是本发明不局限于这种特定实施例,而是在全部权利要求范围之内。
Claims (2)
1、蒸汽透平的蒸汽控制阀(10)阀罩的圆筒(13)内装有阀芯(11),其外表面(19)上有环形的压力密封环槽(41),这个槽有一对相对的侧壁(46、53)和一个底面(61),且其间容纳有压力密封环(43),其特征是:槽(51)轴向延伸进入槽(41)底面(61)和阀芯(11)外表面(19)中间的密封环槽(41)的壁(46、53)之至少一个壁中;而环状磨损环(55)即装在上述的切口(51)中并与上述切口牢固地装配在一起,上述磨损环(55)轴向尺寸大于切口(51)的深度,并在其轴向自由端为倾斜的支撑面(57);且压力密封环(43)装在密封槽(41)内,上述密封环(43)也有倾斜的支撑面(59),其形状恰与上述磨损环(55)上的支撑面(57)相吻合;这上述密封环和磨损环的两个支撑面倾斜的角度要选得在阀芯(11)快速动作到关断阀门的位置时造成加到密封环(43)上向内的作用力。
2、根据权利要求1的阀芯,其特征是:上导向环(45)沿着通过压力密封环槽(41)分隔面可拆卸地装在阀体(47)上,并成为阀芯(11)的一个部件,上述导向环(45)的一部分构成密封环槽(41)的两侧壁(46、53)中至少一个,密封环槽(41)包含上述切口(51)。
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
US07/426,825 | 1989-10-26 | ||
US07/426,825 US4978102A (en) | 1989-10-26 | 1989-10-26 | Aligning and seal ring retracting apparatus for plug type valve |
Publications (1)
Publication Number | Publication Date |
---|---|
CN1051227A true CN1051227A (zh) | 1991-05-08 |
Family
ID=23692351
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
CN90108618A Pending CN1051227A (zh) | 1989-10-26 | 1990-10-25 | 用于柱塞型阀门的对中及密封环回缩装置 |
Country Status (7)
Country | Link |
---|---|
US (1) | US4978102A (zh) |
JP (1) | JPH03153975A (zh) |
KR (1) | KR910008323A (zh) |
CN (1) | CN1051227A (zh) |
CA (1) | CA2028608A1 (zh) |
ES (1) | ES2028550A6 (zh) |
IT (1) | IT1243811B (zh) |
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN104942585A (zh) * | 2015-06-30 | 2015-09-30 | 苏州昌飞自动化设备厂 | 阀芯自动组装机的阀芯顶针分料上料机构 |
Families Citing this family (10)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US6776419B2 (en) * | 2002-06-05 | 2004-08-17 | Gregory S. Antoun | Seal for a reciprocating plunger |
US20060096643A1 (en) * | 2004-11-10 | 2006-05-11 | Mccarty Michael W | Seal assembly for a fluid pressure control device |
US20070246679A1 (en) * | 2006-04-21 | 2007-10-25 | Max Widenmann Kg Armaturenfabrik | Valve, especially for use in fire-fighting |
DE102010037011B4 (de) * | 2010-08-16 | 2013-12-24 | Samson Ag | Stellgerät zur Steuerung eines Fluidstroms |
US9194501B2 (en) | 2012-11-20 | 2015-11-24 | Dresser, Inc. | Pressure balanced spring loaded overtravel sealing apparatus |
US9395019B2 (en) | 2013-06-27 | 2016-07-19 | Dresser, Inc. | Device for sealing a valve |
US10393283B2 (en) | 2017-09-25 | 2019-08-27 | Dresser, Llc | Regulating overtravel in bi-furcated plugs for use in valve assemblies |
WO2019168413A1 (en) * | 2018-02-27 | 2019-09-06 | Apex Valves Limited | Sealing arrangement |
KR102509705B1 (ko) * | 2019-12-30 | 2023-03-15 | 주식회사 삼양사 | 폴리카보네이트 선형 올리고머 혼합물의 분석 방법 및 이를 이용한 폴리카보네이트 고리형 올리고머의 합성 방법 |
CN111928813B (zh) * | 2020-06-30 | 2022-03-22 | 温州大学瓯江学院 | 阀芯组装方法 |
Family Cites Families (8)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US1419857A (en) * | 1920-08-09 | 1922-06-13 | Harry B Johnston | Piston and piston ring |
US1885290A (en) * | 1929-09-06 | 1932-11-01 | Universal Piston Company | Piston |
US2376147A (en) * | 1942-04-29 | 1945-05-15 | Harry B Johnston | Piston and piston ring |
US3605787A (en) * | 1969-12-04 | 1971-09-20 | Chas M Bailey Co Inc | Polyjet valve |
JPS5750368U (zh) * | 1980-09-09 | 1982-03-23 | ||
JPS6059473B2 (ja) * | 1980-11-14 | 1985-12-25 | 東急車輌製造株式会社 | ガス圧縮ピストンにおける高圧シ−ル |
JPS6094657A (ja) * | 1983-10-28 | 1985-05-27 | 合資会社森工場 | たて編方法及びたて編機 |
US4712769A (en) * | 1986-08-29 | 1987-12-15 | White Consolidated Industries, Inc. | High temperature balanced valve trim |
-
1989
- 1989-10-26 US US07/426,825 patent/US4978102A/en not_active Expired - Fee Related
-
1990
- 1990-10-08 IT IT2167490A patent/IT1243811B/it active IP Right Grant
- 1990-10-25 CA CA 2028608 patent/CA2028608A1/en not_active Abandoned
- 1990-10-25 ES ES9002707A patent/ES2028550A6/es not_active Expired - Lifetime
- 1990-10-25 KR KR1019900017138A patent/KR910008323A/ko active IP Right Grant
- 1990-10-25 CN CN90108618A patent/CN1051227A/zh active Pending
- 1990-10-26 JP JP2287399A patent/JPH03153975A/ja active Pending
Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN104942585A (zh) * | 2015-06-30 | 2015-09-30 | 苏州昌飞自动化设备厂 | 阀芯自动组装机的阀芯顶针分料上料机构 |
Also Published As
Publication number | Publication date |
---|---|
IT1243811B (it) | 1994-06-28 |
ES2028550A6 (es) | 1992-07-01 |
IT9021674A1 (it) | 1992-04-08 |
KR910008323A (ko) | 1991-05-31 |
IT9021674A0 (it) | 1990-10-08 |
JPH03153975A (ja) | 1991-07-01 |
CA2028608A1 (en) | 1991-04-27 |
US4978102A (en) | 1990-12-18 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
CN1051227A (zh) | 用于柱塞型阀门的对中及密封环回缩装置 | |
US5215384A (en) | Self-centering squeeze film damper bearing | |
US4981415A (en) | Support for oil film dampers | |
CA1285217C (en) | Wellhead with eccentric casing seal ring | |
US5433529A (en) | Fluid bearing construction employing thrust plate with pressure compensation ports | |
EP1359335B1 (en) | Assembly with an elastically mounted bearing with an oil damper and a method of manufacturing thereof | |
US4344629A (en) | Self-lapping high speed seal with wear-in lip | |
US4305567A (en) | Valve stem seal | |
US4911245A (en) | Metal seal with soft inlays | |
US5697708A (en) | Hydrodynamic bearing with reduced temperature sensitivity | |
EP0293140A2 (en) | Brush seals | |
EP0232178B1 (en) | A fitting for use in a pressurised fluid line | |
GB2263141A (en) | Anti-rotation wiper ring | |
CN1117231C (zh) | 轴的密封装置 | |
US5073036A (en) | Hydrostatic bearing for axial/radial support | |
US6637942B2 (en) | Bearing assembly and method | |
EP1196713B1 (en) | Swivel apparatus | |
CN1072534C (zh) | 轧钢机油膜轴承的互锁密封件和套筒 | |
CN1526977A (zh) | 轴颈密封 | |
JP3307940B2 (ja) | グランドシールアッセンブリ | |
EP0950279B1 (en) | Vibrational control system for stator coils | |
US5251579A (en) | Cylinder liners | |
US4333692A (en) | Hydrostatic axial thrust bearing | |
CA2218516C (en) | A gas seal with locking arrangement | |
EP0223457B1 (en) | Mechanical face seals |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
C06 | Publication | ||
PB01 | Publication | ||
C01 | Deemed withdrawal of patent application (patent law 1993) | ||
WD01 | Invention patent application deemed withdrawn after publication |