WO2001070121A2

WO2001070121A2 - Combined seal with rotary and stationary rings

Info

Publication number: WO2001070121A2
Application number: PCT/BA2001/000003
Authority: WO
Inventors: Tode Stojicic
Original assignee: Tode Stojicic
Priority date: 2000-03-21
Filing date: 2001-03-20
Publication date: 2001-09-27
Also published as: AU2001246253A1; WO2001070121A3

Abstract

Combined seal with rotary and unmoved rings in basic version consists of two unmoved rings, light pressing in the hole of supporting wall with radial gap through shaft and rotary ring between them that is pressing on the shaft and has a radial gap on his outer surface. High efficient seal has greater number in cyclic order mounted unmoved rings (12) and rotary rings (14) which are pressing in rotary (32) and consequently in unmoved part of seal housing (30). The rings have side grooves (26) in which O-rings are mounted through which serve to make slip contact and axial gap between them. Rotary part of housing (32) is put on the shaft (18), while unmoved is pressing in hole in the wall (16). For bad leading shafts and limited space capabilities very useful solutions are seals with thin unmoved lamellas and rotary lamellas. Between these lamellas has been making axial gap using circle convexity or using free installed O-rings. Seal versions mentioned above are very useful for high temperature and high pressure because there are no limits in material selection for working parts.

Description

COMBINED SEAL WITH ROTARY AND UNMOVED RINGS

Technical Field related to invention

Suggested invention is related to the seal with in cyclic order mounted rotary and unmoved circle rings at which have been using both labyrinth effects and local friction contact. The seal is intended for sealing of shafts and other different machines rotary parts like bearings, etc. and corresponding ICP preferable group may be: F 16 J 15/44; 15/54: F 16 C 33/72; 33/74; 33/76 and 33/78.

Background Art

Seals for rotary machine parts in many industrial applications have been exposed to high mechanical and thermal loads, aggressive media actions and very negative influences irregular o motions of rotary parts that are a product of: gaps in bearings, manufacturing errors, part deformations and oscillations during machine dynamic loads. Good hermetic state, reliable exploitation period, longlife and general economy are the basic demands for the best and most complicated seals and sometimes it is very difficult to achieve the same.

In solving of the above technical problem many different designs have been using. However, ι5 the following groups are the most popular: without contact and with friction contact of functional elements. The first group consists of great number of labyrinth seals for high temperature and lower pressure. In this case, incomplete sealing, complicate production and huge dimensions very often are the basic faults. The second group consists of seals based on the friction between parts in contact like full rings of elastic and soft materials. In this case high 2o friction losses, enormous friction wears and relatively short exploitation period are present. Use of improved seals with flexible lips and radial springs pressure is the most popular. These seals have good features, but in the same time a sensitivity of seal lips during hard exploitation period as well as temperature limit.

Also, improved two ring seals have been used. The basic characteristic of this seal is a high 25 axial pressure under spring action. Beside the complexity and greater dimensions, the loss of friction and limits of working temperatures are present too.

According to the domestic and international literature related with this problem area as well as information data of manufacturers (Goetze, Busak & Luyken, Kako, Carl Freudenberg Simrit, Angus & Co. Ltd, etc.) and working principles and design, there is no similar solution that 3₀ could be compare to the invention.

Disclosure of the Invention

The aim of the invention is a realization of seal for rotary machine parts that could solve all demands above mentioned. From this reason, the invention uses effect of labyrinth sealing, improved gaps (small and simple definable) between rings and their environment, effect of 3? reliable sealing through local small surface contacts on rings and therefore less friction loss. According to the invention, basic seal consist of simple, in cyclic order mounted rotary and unmoved rings (rectangle cross section). Rotary rings over own internal radial surfaces directly or over cut across layer of predominant softly material are light pressing on the shaft through fixed junction, while unmoved rings on the same way over outer radial surfaces pressing in the 5 holes in supporting wall. Mounted rings have side contact while small axial gap is seting up during initial rings rotating. Efficient sealing with less friction could be achieved by using of axial circle grooves. The grooves, like radial and axial gaps between rotary an unmoved parts, are mostly fill out with usual longlife lubricate mean.

According to the invention, for strict sealing demands and reliable during exploitation period

-10 seals with greater number of rings and axial grooves could be a very efficient solution, especially for high fluid pressure. The O-rings are mounted in the grooves what serves for axial contact and definition of axial gap between the rings. In this case, rotary and unmoved rings are mounted by pressing in corresponding parts of seal housing. A rotary part of seal housing is slip on the shaft while unmoved part is pressing in the hole of supporting wall. According to the

<_j5 same principles, the invention offers a special seal design for more stricter demands like application in the case of bad shaft leading. The special design is based on the combination of rotary and unmoved lamellas where axial contacts and axial gaps are solved by wire O-rings or circle convexity use. Beside good characteristics, lamella design of seal has smaller dimensions and very economic production. Based on the invention, the seal offers many advantages in zo relation with present state of the art and it is very useful in application with high temperature and high fluid pressure because there are no limits in material selection.

Brief Description of the Drawings

Given drawings are integral parts of the invention description. The figures represent:

Fig.1. Axial cross section of seal with series of simple rings. 25 Fig.2. Unmoved ring with grooves in the layers of soft material on the outer radial surface.

Fig.3. Rotary ring with grooves in the layers of soft material on the internal radial surface.

Fig.4. Ring with axial and radial grooves for lubrication or other similar sealing mean.

Fig.5. Seal assembly with series of rings with axial grooves and O-rings mounted at the grooves. 50 Fig.6. Unmoved and rotary ring with both side axial grooves for O-rings.

Fig.7. Unmoved and rotary rings with one side axial grooves for O-rings.

Fig.8. Seal with flat unmoved lamellas and both side convexes on the rotary lamellas.

Fig.9. Seal with flat lamellas and O-ring on the internal radial side of unmoved lamellas, and

Fig.10. Seal with free mounted O-rings between rotary lamellas.

35 Specific Description of the Invention

The basic invention is presented in the fig. l to fig.4. It is consisted from two simple unmoved rings 12 and rotary ring 14 between unmoved rings. Over outer radial surface unmoved rings 12 are light pressing in the hole of supporting wall 16, (small positive and negative gaps), while the rotary ring 14 over internal radial surface is light pressing on the shaft 18. Radial gaps £fθ between other radial surfaces exist. After installation, rings are making side contacts and after initial working the rings have been moved, depend of rotation shaft errors. On that way, a small axial gap is obtained in local area. For easier installation and better sealing on the outer surface of unmoved ring 12 could be made, according to fig. 2., cut across layer 20 of soft material as well as on the internal radial surface 20 of internal rotary ring 14, according to the fig. 3. The ring with low radial groove 22 and axial groove 24 that are fill up by full sealing mean or lubrication, according to the fig. 4., 5 obtains improved sealing.

According to the fig. 5. to fig. 1., better sealing could be achieved by seal with a greater number of unmoved rings 12 and rotary rings 14 which contain axial grooves 26 for location of O-rings 28. The O-rings serve to make local contacts and necessary axial gaps between the rings. Using assembly, unmoved rings 12 are pressing in the fixed part of housing 30, while rotary rings 14 0 are pressing in the rotary part of seal housing 32. During montage, rotary part of seal housing 32 has been pressing on the shaft 18 while unmoved part of seal housing 30 in the hole of supporting wall 16. Axial grooves 26 serve for leading O-rings 28 and could be both sides produced, that is shown in the fig. 6. Version with one side is shown in the fig.7. Axial and radial gaps usually contain mean for longlife lubrication in order to obtain efficient sealing. An 5 example of seal functioning is presented in the fig. 5. During shaft rotation, internal part of housing also performing rotation together with rotary ring 12 what results relatively motion in relation with wire O-ring 28 placed in axial groove 26. Since small radial and axial gaps are fill up with lubrication mean and according to the labyrinth effect high efficient sealing results could be achieved even in the case of great pressure differences. Complete effect of reliable ₀ sealing is obtained in local contacts between rotary rings 14 and unmoved rings 12 using wire O ring with presence of slipping in both grooves and low friction. These contacts and gaps make possible compensation of rotating shaft errors and own oscillations.

In the case of the seal, shown in the fig. 8., rings are replaced with flat unmoved lamellas 34 and rotary lamella 36 with two side circle axial convexes 37. High of these convexes define 5 axial gap between lamellas. Lamellas are made by pressing flat thin sheet metals and rotary lamellas 36 create internal hubs 37' while unmoved lamellas 34 create outer hubs 35. Lamellas are installed over these hubs with cyclic order (rotary-unmoved) in unmoved part 30 and rotary part of seal housing 32. Gaps are durable lubricated. After thermic treatment lamellas have spring properties and from that reason seals are flexible and they have possibilities to io compensate considerable errors during rotation of shafts and other rotary parts.

Versions presented in the fig. 9. and fig. 10. based on both labyrinth and friction contact sealing, but in this case all lamellas are flat. O-rings 38 on internal radial surface of unmoved lamella (fig. 9.) could be tightened or made as unique assembly; for example synthetic lamellas. According to the fig. 10., wire O-rings are installed in axial directions between the root of _ζ rotary lamellas 36 with small gaps and local contacts in radial directions through the tops of unmoved lamellas 34.

Industrial application

According to the invention, seal could be very useful in sealing of shafts and other rotary parts different machines as well as in conditions of high temperatures and pressures (IC engine, iro steam and gas turbine, etc.). Reasons for wide applications could be explained with the possibilities in material selection for different parts, also including "ceramics". Since presented inventions are better then great number of modern seals, up today experience could be enough for successful manufacturing any of presented type of seal presented in this invention.

Claims

1. Combined seal with rotary and unmoved rings, consisted of pair of rings, where one of them is usually put on the rotary part and the other on unmoved part and there is under relatively high axial pressure using special spring, characterized by, it is consist of in cyclic order mounted rotary and unmoved rings; said rotary rings over internal radial surface directly or

§ over cut across layer of a predominant soft material in the circular grooves on that surface mounted by pressing on the shaft through fixed junction; said unmoved rings over their outer radial surfaces pressing in the hole in supporting wall; said rings mounted with zero or very small axial gaps or with contacts; and said rings have radial gaps between unmoved rings and the shaft as well as between rotary rings and surface of hole in the supporting

\0 wall.

2. Seal defined in claim 1, characterized by, that seal consists of rotary part of seal housing which is pressed on the shaft and unmoved part of housing which is pressed in the hole of supporting wall; the rotary and unmoved rings mounted in cyclic order with pressing on the rotary part of seal housing and in unmoved part of seal housing; said rings having circular

1S grooves on its both side axial surfaces or only on its one side; the wire O-rings placed in said circular grooves; said seal rings have axial gaps between them; and said seal rings have radial gaps between unmoved rings and the rotary part of the seal housing and between rotary rings and unmoved part of housing .

3. Seal defined in claims 1 and 2, characterized by, that rotary and unmoved rings have a form lo of thin flat lamellas or lamellas with both side axial convexity; said unmoved lamellas are placed by pressing in the unmoved part of housing, while rotary lamellas are placed by pressing in the rotary part of seal housing; that between lamellas are small axial gaps; and that between said lamellas and corresponding housing port there are radial gaps.

4. Seal defined in claims 2 and 3, characterized by, that rotary and unmoved lamellas are flat 2S and that on the internal radial surface of unmoved lamellas there are wire O-rings.

5. Seal defined in claim 4, characterized by, that between rotary lamellas, near its roots, wire O-rings there are placed; and that in radial direction through hubs of rotary rings and internal surface of unmoved lamellas there are very small gaps.