Description:
FIELD OF THE INVENTION:
[001] This invention is directed to an assembly of access door cum observation port for steam generator furnaces.

[002] This invention relates to the observation port mounted access door assembly design for High pressure High temperature Steam Generator for thermal power plants. More particularly the invention relates to new design of access door assembly on which an observation door assembly is attached. This assembly doubles up as a single unit serving both for access during shut down and for observing boiler under operation.

BACKGROUND/PRIOR ART OF THE INVENTION:
[003] 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.

[004] In a boiler many types of doors are being provided for various purposes. Water or air cooled Access doors, scaffold doors, observation ports are used extensively in steam generators. The doors are either located in a steam carrying tube wall or duct wall. The design of various types of doors depends on the type of steam generator operation. The operation of furnace can be positive pressure type, negative pressure type or balanced draft type. The access doors, observation ports are two unique assemblies and are located at various elevations of the steam generator based on the operation and/or maintenance requirements. The cooling arrangement of access doors, observation ports are based on water or air cooled types.

[005] According to the prior art the access door and observation ports are two different assemblies. They can be of water-cooled type or air cooled type depending on the operation parameters. The doors and ports are attached to a seal box. The seal box is in turn attached to the steam carrying tubed wall. Due to layout considerations, the access doors and observation ports are being provided on various elevations based on operation and maintenance requirements.

[006] An access door is being used as entry/exit into the steam generator while the unit is under shutdown. An observation port is used to monitor hot conditions inside the steam generator when it is under operation. According to the type of door, openings are being provided along with seal box frames in steam generator elevations. However the number of openings for an access door and an observation ports are different. So in selective locations where there is a need for both observation port and access doors, the same cannot be provided. This leads to lack of visibility of operating conditions inside of the steam generators as an access door cannot be opened during operation and is meant only for opening during shutdown and for maintenance of boiler. Opening the same causes high radiation of heat causing unsafe hot conditions on the opening platform thereby causing injury to the door operator.

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

OBJECTS OF THE INVENTION:
[008] An object of the present invention is to provide an assembly of access door cum observation port for steam generator furnaces, which has a single assembly design that has provisions for both access door and observation port.

[009] Another object of the present invention is to provide an assembly of access door cum observation port for steam generator furnaces,that doubles up as observation port while in operation and as access door while the steam generator is under shutdown.

[0010] Still another object of the present invention is to provide an assembly of access door cum observation port for steam generator furnaces, which also reduces number of openings that are to be provided at various elevations in steam generator, wherein a single opening at an elevation can mount an access door cum observation port.

[0011] Yet another object of the present invention is to provide an assembly of access door cum observation port for steam generator furnaces, which is simple in construction.

[0012] 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:
[0013] 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.

[0014] Accordingly, the observation port is mounted on the outer cover of the access door and in order to protect the heat, shaped refractory blocks with opening slots are provided to ensure visibility through observation port. With this setup there is no requirement for observation port seal box. An access door seal box, the access door assembly is mounted over which the observation door assembly is mounted. Thus, the new design ensures a combination of Access door with Observation door at a single elevation location of boiler.

[0015] However, this arrangement will work in negative pressure or balanced draft locations of steam generator zones. Thus the observation port mounted access door assembly has been conceived.

[0016] The present invention is achieved by the features of principal claim and subsequent claims.

[0017] 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.

[0018] 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.

[0019] 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:
[0020] The illustrated embodiments of the subject matter will be best understood by reference to the drawings, wherein like parts are designated by like numerals throughout. The following description is intended only by way of example, and simply illustrates certain selected embodiments of devices, systems, and processes that are consistent with the subject matter as claimed herein, wherein:-
[0021] Figure 1 shows the elevation view of existing assembly of access door.
[0022] Figure 2 shows the side view of the existing assembly of access door.
[0023] Figure 3 shows the plan view of the existing assembly of observation door.
[0024] Figure 4 shows elevation view of proposed assembly of access door mounted with observation port.
[0025] Figure 5 shows the side view of proposed assembly of access door mounted with observation port.
[0026] Figure 6 shows plan view of the proposed access door mounted with observation port.
[0027] Figure 7 shows the assembly of observation port mounted on Access door plate.

[0028] 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:

[0029] 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.

[0030] The present invention makes a disclosure regarding a technology pertinent to an assembly of access door cum observation port for steam generator furnaces.

[0031] Now reference may be made to Figure-1 illustrating the elevation view of the assembly of an access door comprising a cover plate (01). In order to strengthen the door cover plurality of stiffener plates (04) are provided. A door handle (06) is attached to the cover plate (01) so that the access door can be opened by using handle.

[0032] Now referring to Figure-2 showing the side view of the access door in which lug plates (02), (03), and (05) are attached to the door cover plate (01).

[0033] Figure- 3 shows the plan view of an access door assembly. From this view, a box type arrangement using plate (07) is seen which is provided to hold refractory (08) to prevent the cover plate (01) from heat attack. The refractory (08) is held in position using steel anchors (09). The refractory box and the whole door cover plate assembly is held together using fastener including screw nut and washer kit (10).

[0034] Now reference may be made to Figure-4, Figure-5 and Figure-6 showing new access door design having observation door assembly (11) mounted to its frame. The observation door assembly plate is directly welded to the access door frame (01) at desired observation location. The gap between the observation door assembly (11) and cover plate (01) is filled using packing rope (12). In order to get a complete view of the furnace inside, the refractory (08) is removed based on rectilinear profile of view port through observation door. Steel anchors (09) are re positioned to hold refractory with a view gap (08).

[0035] The Present invention relates to the access door with observation port design for steam generator for Thermal Power plants. The access door and observation port are located in different locations based on the operation and maintenance requirements. The new design can be provided at same opening location of furnace steam cooled walls. The design comprises of an observation port (11) that is mounted on the outer cover (1) of the access door. This combined door design can be located in steam carrying tube wall. The access door is being used as entry and exit into the steam generator for maintenance during shut down and observation port is provided for observing the working condition of the steam generator furnace. A door handle (6) is attached on the cover plate (1) to facilitate opening of access door. The gap between the cover plate (1) and observation port (11) is filled with packing ropes (12). Refractory (8) is provided for heat protection for operator as well as for cover plate from the heat attack.

[0036] The refractory (8) is placed in such a way that when an operator views by opening the observation port, the blocks have necessary gap through opening and hence do not obstruct the view of inside of the furnace. To hold the refractory inside, plate (7) is used and it is held in position with the help of steel anchors (9). The stiffener plates (4) and lug plates (2), (3), (5) are attached to the cover plate (1) for the purpose of strengthening the door. Therefore, the whole arrangement is held together with the help of washer and screw nut kit (10).

[0037] The advantage of present Invention is that it reduces the number of door openings in the tubed wall surface.

[0038] 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.

[0039] 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.

[0040] 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.

[0041] 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”.

[0042] 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.

[0043] 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.
[0044] 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.

[0045] 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.

Claims:WE CLAIM

1. An assembly of access door cum observation port for steam generator furnaces comprising:
an observation port (11) mounted on an outer cover plate (1) of an access door assembly;
stiffener plates (4) and lug plates (2, 3, 5) are attached to the outer cover plate (1) for strengthening the door;
a refractory (8) is provided for heat protection for operator as well as for the outer cover plate (1) from the heat attack and is placed that when an operator views by opening the observation port, the blocks have through opening and do not obstruct the view of inside the furnace;
a plate (7) is provided to hold the refractory inside and it is held in position by anchors (9).

2. The assembly of access door cum observation port for steam generator furnaces as claimed in claim 1, wherein a door handle (6) is attached on the outer cover plate (1) to facilitate opening of access door.

3. The assembly of access door cum observation port for steam generator furnaces as claimed in claim 1 or 2, wherein the refractory box and the whole door cover plate assembly is held together using fastener including screw nut and washer kit (10).

4. The assembly of access door cum observation port for steam generator furnaces as claimed in claims 1-3, wherein the access door is having observation door assembly (11) mounted to its frame, in which the observation door assembly plate is welded to the access door frame (01) at desired observation location.

5. The assembly of access door cum observation port for steam generator furnaces as claimed in claims 1-4, wherein the gap between the observation door assembly (11) and cover plate (01) is filled using packing rope (12); in order to get a complete view of the furnace inside, the refractory (08) is removed based on rectilinear profile of view port through observation door and Steel anchors (09) are re positioned to hold refractory with a view gap (08).

6. The assembly of access door cum observation port for steam generator furnaces as claimed in claims 1-5, which can be provided at same opening location of furnace steam cooled walls, in which the combined door design can be located in steam carrying tube wall.

7. The assembly of access door cum observation port for steam generator furnaces as claimed in claims 1-6, wherein the access door is used as entry and exit into the steam generator for maintenance during shut down and observation port is provided for observing the working condition of the steam generator furnace.

8. The assembly of access door cum observation port for steam generator furnaces as claimed in claims 1-7, wherein the access door and observation port are located in different locations based on the operation and maintenance requirements.

9. The assembly of access door cum observation port for steam generator furnaces as claimed in claims 1-8, wherein the access door assembly having an observation port mounted thereon can be utilized in balanced draft boiler operations and reduces the number of door openings in the tubed wall surface.