Claims:WE CLAIM
1. A device (09) for protecting the stationary Spool Seal (01) arrangement for Guide bearing Assembly for Air preheater comprising:
an inner spool seal ring (10);
a Packing retainer plate (12);
a Packing Rope-B (11);
wherein the device (09) arrangement is introduced in the bottom side of the Guide Bearing Stationary Spool Seal (01) Arrangement.
2. The device (09) as claimed in claim 1, wherein the inner spool seal ring (10) is made up of thick walled plate in halves, which is positioned around the device (09) and both the halves are bolted each other.
3. The device (09) as claimed in claim 1, wherein the Packing Rope-B (11) is positioned in between inner spool seal ring (10) and Spool seal (01).
4. The device (09) as claimed in claim 1, wherein the Packing Rope-B (11) is tightly positioned in its location using packing retainer plate (12).
, Description:FIELD OF THE INVENTION:
[001] This invention relates generally to the development of improved sealing arrangement for the Stationary Spool Seal arrangement for Guide bearing assembly for Air preheater. More particularly the invention relates to an improved and better sealing arrangement to contain leakage and damage of packing insulation, sealing ropes and packing retainer caused by impinging high pressure hot Air with ash.

BACKGROUND/PRIOR ART OF THE INVENTION:
[002] Background description includes information that may be useful in understanding the present invention. It is not an admission that any of the information provided herein is prior art or relevant to the presently claimed invention, or that any publication specifically or implicitly referenced is prior art.

[003] Rotary Regenerative Air preheaters are used in thermal power station and industrial applications to extract the heat from the flue gases that are leaving the boiler furnace and transfer the heat to the incoming combustion air.

[004] For the effective heat transfer, Rotary Regenerative Air preheater uses rotor assembly, which is having heat transfer elements packed in baskets. The rotor is divided into compartments by a number of radially extending plates referred as diaphragms. These compartments are adapted to hold number of baskets which contain the mass of heat absorbent material commonly formed of stacked plate-like elements. The baskets are positioned and supported by Rotor post. The rotor post is revolving on support bearing assembly located in Cold End Centre section. The rotor post is guided by the trunnion revolving in the Guide bearing assembly which is positioned in the hot end centre section.

[005] The Guide bearing spool seal is provided to seal the Hot air which is leaving the Air-heater. However, during the rotation of rotor assembly, the sliding surfaces between spool seal and rotor is introducing a small gap between them. The high pressure Hot air with ash tends to impinge through this gap and damages the guide bearing assembly. Over the period of time, the high pressure Hot air laden ash, further damages the insulation rope available in the spool seal retainer and causes leakage in the air heater. The hot air leakage near guide bearing area is a perennial issue in Air preheaters.

[006] Presently, hot air with ash leakage over the guide bearing assembly is leading to contamination of guide bearing oil and heating up of the guide bearing and leading to substantial reduction in bearing life. It was observed in many operating Air preheaters that the hot air leakage near guide bearing area is heavy with ash. It was due to failure of the existing spool seal assembly due to high pressure contaminated hot air with ash jetting with higher velocity erodes the spool seal assembly in short time. The operation staff finding it difficult to approach the Guide bearing area for routine maintenance.

[007] In view of the above, there is requirement to devise an apparatus which can address the aforesaid shortcoming(s). Hence, the present invention has been introduced to overcome this problem.

[008] The information disclosed in this background of the disclosure section is only for enhancement of understanding of the general background of the invention and should not be taken as an acknowledgement or any form of suggestion that this information forms the prior art already known to a person skilled in the art.

OBJECTS OF THE INVENTION:
[009] It is therefore the object of the present subject matter to overcome the aforementioned and other drawbacks in prior method/product/apparatus.

[0010] The present invention is based on the object of providing an improved Guide bearing spool seal arrangement for the Guide bearing assembly of the air preheater.

[0011] Said object is achieved according to the invention by the features of claim 1. Further, particularly advantageous embodiments of the invention are disclosed in the sub-claims.

[0012] Another object of the present invention is to reduce damage of insulation and packing retainer caused by impinging high pressure hot Air.

[0013] Yet another objective of the present invention is to reduce the leakage of Air preheater system and improve the life of the Guide bearing Assembly.

[0014] These and other objects and advantages of the present invention will be apparent to those skilled in the art after a consideration of the following detailed description taken in conjunction with the accompanying drawings in which a preferred form of the present invention is illustrated.

SUMMARY OF THE INVENTION:
[0015] One or more drawbacks of conventional systems and process are overcome, and additional advantages are provided through the apparatus/composition and a method as claimed in the present disclosure. Additional features and advantages are realized through the technicalities of the present disclosure. Other embodiments and aspects of the disclosure are described in detail herein and are considered to be part of the claimed disclosure.

[0016] The sealing arrangement of Guide bearing stationary spool seal assembly is improved by introducing inner spool sealing ring with packing between the static and moving components of guide bearing assembly. This is accomplished by making necessary modifications in guide bearing stationary spool seal assembly by introducing inner spool seal. The inner spool is a thick walled ring, which is positioned around the spool using bolting arrangement. The packing rope is tightly positioned over the sealing ring and is kept in position by a locking retainer plate, which is fixed on the sealing ring by mechanical means.

[0017] By introducing the inner spool seal in the stationary spool seal arrangement, the air gap between the moving and static component is effectively reduced. Since the direct impingement of hot Air with ash is avoided, the life of Guide bearing assembly is improved. Also the effective performance of stationary spool seal arrangement is improved.

[0018] The present invention is achieved by the features of principal claim and subsequent claims.

[0019] Various objects, features, aspects, and advantages of the inventive subject matter will become more apparent from the following detailed description of preferred embodiments, along with the accompanying drawing figures in which like numerals represent like components.

[0020] It is to be understood that the aspects and embodiments of the disclosure described above may be used in any combination with each other. Several of the aspects and embodiments may be combined to form a further embodiment of the disclosure.

[0021] The foregoing summary is illustrative only and is not intended to be in any way limiting. In addition to the illustrative aspects, embodiments, and features described above, further aspects, embodiments, and features will become apparent by reference to the drawings and the following detailed description.

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS:

[0022] It is to be noted, however, that the appended drawings illustrate only typical embodiments of the present subject matter and are therefore not to be considered for limiting of its scope, for the invention may admit to other equally effective embodiments. The detailed description is described with reference to the accompanying figures. In the figures, a reference number identifies the figure in which the reference number first appears. The same numbers are used throughout the figures to reference like features and components. Some embodiments of system or methods or structure in accordance with embodiments of the present subject matter are now described, by way of example, and with reference to the accompanying figures, in which:

[0023] Figure 1 illustrates the prior art design of Stationary Spool sealing arrangement for Guide bearing.

[0024] Figure 2 illustrates the closer view of the inner sealing area for Prior Art Guide bearing.

[0025] Figure 3 illustrates the improved stationary spool sealing arrangement.

[0026] Figure 4 illustrates the closer view of improved inner spool sealing arrangement.

[0027] The figures depict embodiments of the disclosure for purposes of illustration only. One skilled in the art will readily recognize from the following description that alternative embodiments of the structures and methods illustrated herein may be employed without departing from the principles of the disclosure described herein.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENT(S) OF THE PRESENT INVENTION WITH REFERENCE TO THE ACCOMPANYING DRAWINGS:

[0028] While the embodiments of the disclosure are subject to various modifications and alternative forms, specific embodiment thereof have been shown by way of example in the figures and will be described below. It should be understood, however, that it is not intended to limit the disclosure to the particular forms disclosed, but on the contrary, the disclosure is to cover all modifications, equivalents, and alternative falling within the scope of the disclosure.

[0029] The present invention makes a disclosure regarding a technology pertinent to improving the sealing arrangement for the Stationary Spool Seal arrangement for Guide bearing assembly for Air preheater.

[0030] The Present invention relates to the improved and better sealing arrangement to reduce hot air leakage and damage of sealing insulation, sealing ropes and packing retainer caused by impinging high pressure hot Air.

[0031] Now reference may be made to Figure-1 and 2 illustrating the general arrangement of the Guide bearing stationary spool seal to protect the Guide bearing assembly from high pressure hot Air leaving the Air preheater. The guide bearing spool (01) is in contact with the sealing plate (02). Sealing Plate (02) is positioned in the retainer (04) with ceramic insulation (08). In the top side packing retainer (03) is provided, which is supported on the spool support ring (04). In between packing retainer (03) and spool seal (01), packing rope-A (05) is tightly positioned using packing cover ring (06) which is kept in tight condition using plate lock washer and Nut (07). The sealing plate (02) which is in contact with guide bearing Spool (01) is rubbing each other and over the period of time, the air gap is induced which leads to the entrapment of high pressure hot air and further causes the damage of ceramic insulation (08) as shown in Figure. 2.

[0032] Now referring to Figure-3 and 4 showing the Improved Guide bearing sealing arrangement. The new inner spool seal arrangement (09) is introduced in the bottom side of the Guide Bearing Stationary Spool Seal Arrangement. The inner spool seal (09) consists of inner spool seal ring, packing retainer plate (12) and Packing Rope-B (11). The inner spool seal ring (10) is made up of thick walled plate in halves, which is positioned around the spool seal and both the halves are bolted each other. Packing Rope-B (11) is positioned in between inner spool seal ring (10) and Spool seal (01). The Packing Rope-B (11) is tightly positioned in its location using packing retainer plate (12). By the development and the introduction of Inner Spool Seal (09) arrangement in the guide bearing Stationary Spool Seal, the direct impingement of high pressure hot air into the Guide bearing is avoided and the effectiveness of sealing system is improved.

[0033] The advantage of present Invention is that it reduces damage of insulation and packing retainer caused by impinging high pressure hot Air.

[0034] Another advantage of present Invention is that it reduces the leakage of Air preheater system.

[0035] One more advantage of present Invention is that it improves the life of the Guide bearing Assembly.

[0036] The material above has been given as an example without restricting scope of the invention to the same. Thus, other materials readily apparent to a person skilled in the art are within scope of the invention.

[0037] Each of the appended claims defines a separate invention, which for infringement purposes is recognized as including equivalents to the various elements or limitations specified in the claims. Depending on the context, all references below to the "invention" may in some cases refer to certain specific embodiments only. In other cases, it will be recognized that references to the "invention" will refer to subject matter recited in one or more, but not necessarily all, of the claims.

[0038] Groupings of alternative elements or embodiments of the invention disclosed herein are not to be construed as limitations. Each group member can be referred to and claimed individually or in any combination with other members of the group or other elements found herein. One or more members of a group can be included in, or deleted from, a group for reasons of convenience and/or patentability. When any such inclusion or deletion occurs, the specification is herein deemed to contain the group as modified thus fulfilling the written description of all groups used in the appended claims.

[0039] It will be understood by those within the art that, in general, terms used herein, and especially in the appended claims (e.g., bodies of the appended claims) are generally intended as “open” terms (e.g., the term “including” should be interpreted as “including but not limited to,” the term “having” should be interpreted as “having at least,” the term “includes” should be interpreted as “includes but is not limited to,” etc.). It will be further understood by those within the art that if a specific number of an introduced claim recitation is intended, such an intent will be explicitly recited in the claim, and in the absence of such recitation no such intent is present. For example, as an aid to understanding, the following appended claims may contain usage of the introductory phrases “at least one” and “one or more” to introduce claim recitations. However, the use of such phrases should not be construed to imply that the introduction of a claim recitation by the indefinite articles “a” or “an” limits any particulars claim containing such introduced claim recitation to inventions containing only one such recitation, even when the same claim includes the introductory phrases “one or more” or “at least one” and indefinite articles such as “a” or “an” (e.g., “a” and/or “an” should typically be interpreted to mean “at least one” or “one or more”); the same holds true for the use of definite articles used to introduce claim recitations. In addition, even if a specific number of an introduced claim recitation is explicitly recited, those skilled in the art will recognize that such recitation should typically be interpreted to mean at least the recited number (e.g., the bare recitation of “two recitations,” without other modifiers, typically means at least two recitations, or two or more recitations). Furthermore, in those instances where a convention analogues to “at least one of A, B and C, etc.” is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., “a system having at least one of A, B and C” would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). In those instances where a convention analogous to “at least one of A, B, or C, etc.” is used, in general such a construction is intended in the sense one having skill in the art would understand the convention (e.g., “a system having at least one of A, B, or C” would include but not be limited to systems that have A alone, B alone, C alone, A and B together, A and C together, B and C together, and/or A, B, and C together, etc.). It will be further understood by those within the art that virtually any disjunctive word and/or phrase presenting two or more alternative terms, whether in the description, claims, or drawings, should be understood to contemplate the possibilities of including one of the terms, either of the terms, or both terms. For example, the phrase “A or B” will be understood to include the possibilities of “A” or “B” or “A and B”.

[0040] The above description does not provide specific details of manufacture or design of the various components. Those of skill in the art are familiar with such details, and unless departures from those techniques are set out, techniques, known, related art or later developed designs and materials should be employed. Those in the art are capable of choosing suitable manufacturing and design details.

[0041] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the present disclosure. It will be appreciated that several of the above-disclosed and other features and functions, or alternatives thereof, may be combined into other systems or applications. Various presently unforeseen or unanticipated alternatives, modifications, variations, or improvements therein may subsequently be made by those skilled in the art without departing from the scope of the present disclosure as encompassed by the following claims.

[0042] The claims, as originally presented and as they may be amended, encompass variations, alternatives, modifications, improvements, equivalents, and substantial equivalents of the embodiments and teachings disclosed herein, including those that are presently unforeseen or unappreciated, and that, for example, may arise from applicants/patentees and others.

[0043] While various aspects and embodiments have been disclosed herein, other aspects and embodiments will be apparent to those skilled in the art. The various aspects and embodiments disclosed herein are for purposes of illustration and are not intended to be limiting, with the true scope and spirit being indicated by the following claims.