Claims:WE CLAIM
1. An assembly for access door cum air cooled observation port arrangement comprising:
a door handle (06) is attached on the cover plate (01) to facilitate opening of access door and multiple stiffener plates (04) are provided for the cover plate (01) for strengthening the door;
lug plates (02), (03), (05) are attached to the cover plate (01);
a box type arrangement including plate (07) is provided at ends to hold and orient refractory (08);
an observation port handle (11) is attached to the observation port;
a flap (12) is located inside the view path of observation port;
an air flow hose (13) is attached to the steel flap (12);
a sight glass (14) is provided at the outer side of air cooled observation port.

2. The assembly as claimed in claim 1, wherein the observation port is mounted on the outer cover plate (01) of the access door using fasteners including a screw, nut and washer kit (10) and the assembly is located in a tube steam carrying tube wall of the furnace of steam generator.
3. The assembly as claimed in claim 1 or 2, wherein the observation port handle (11) lifts the flap (12) made of material including Steel to view the furnace under operation using the sight glass (14).
4. The assembly as claimed in claims 1-3, wherein an anchor (09) is attached with plate (07) to hold refractory (08) and the anchors (09) made of material including Steel are positioned to hold refractory (08) with a view gap.
5. The assembly as claimed in claims 1-4, wherein the box type arrangement with plate (07) holds the refractory (08) to prevent the cover plate (01) from heat attack.
6. The assembly as claimed in claims 1-5, wherein the air hose (13) provides cooling air flown into the steam generator to negate any gush of flue gas / heat due to pressurized operating conditions inside.
7. The assembly as claimed in claims 1-6, wherein to get a complete view of the furnace inside, the refractory (08) is removed based on corresponding profile of view port through observation door.
8. The assembly as claimed in claims 1-7, wherein to use this observation port under pressurized conditions air flow is ensured through air flow hose (13).
, Description:AN ASSEMBLY OF ACCESS DOOR CUM AIR COOLED OBSERVATION PORT FOR STEAM GENERATOR FURNACES

FIELD OF THE INVENTION:
[001] This invention relates to an air cooled observation port mounted access door assembly design for pressurized locations of 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 air cooled observation door assembly is attached. This assembly doubles up as a single unit serving both for access during shut down and for observing pressurized locations of boiler while in operation.

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] In a boiler many types of doors are being provided for various purposes. 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.

[004] An access door is being used as entry/exit into the steam generator while the unit is under shutdown.

[005] An observation port is used to monitor hot conditions inside of the steam generator when it is under operation.

[006] 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 locations of the steam generator based on the operation and/or maintenance requirements. The cooling arrangement of access doors, observation ports are based on uncooled or water cooled or air cooled types.

[007] According to the prior art the access door and observation ports are two different assemblies. They can be of water-cooled, air cooled or uncooled types depending on the operation parameters. Water and air cooled types are used in pressurized conditions of operation in a boiler. The doors and ports are attached to a seal box. The seal box is in turn attached to the steam carrying tubed wall.

[008] Due to layout considerations, the access doors and observation ports are being provided on various locations based on operation and maintenance requirements.

[009] In a prior art, US2926658A, titled “Shutter type furnace observation port” relates to a furnace observation port and more particularly to a furnace observation port of the shutter type having means for air cooling of the lens thereof. Modern steam generating furnaces operate under pressure above atmospheric pressure and require means for viewing the interior of the furnace while in operation.

[0010] In another prior art, US20160033202A1, titled “Door assembly for use with a furnace” one of a peep hole assembly is connected to the door assembly such that the interior of the furnace can be viewed through the peep hole assembly can be exposed to internal conditions in the furnace.

[0011] 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.

[0012] This leads to lack of visibility of operating conditions inside the steam generators as an access door cannot be opened during operation and is meant only for opening during shutdown, maintenance of boiler. Opening the same will cause high radiation of heat, escape of flue gases causing unsafe hot conditions on the opening platform thereby causing injury to the door operator.

[0013] 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 serve the purpose efficiently.

[0014] 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:
[0015] It is therefore the object of the present subject matter to overcome the aforementioned and other drawbacks in prior method/product/apparatus.

[0016] The present invention is based on the object of providing a single assembly design that has provisions for both access door and an air cooled observation port for pressurized operating locations in boiler.

[0017] Another object of the present invention is to address the need for utilizing an assembly that doubles up as observation port while in operation and as access door while the steam generator is under shutdown.

[0018] Yet another object of the present invention is to reduce number of openings that are to be provided at various locations of a pressurized steam generator.

[0019] 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:

[0020] 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.

[0021] According to the present invention, there is provided an assembly for access door cum air cooled observation port arrangement comprising:
a door handle is attached on the cover plate to facilitate opening of access door and multiple stiffener plates are provided for the cover plate for strengthening the door;
lug plates are attached to the cover plate;
a box type arrangement including plate is provided at ends to hold and orient refractory;
an observation port handle is attached to the observation port;
a steel flap is located inside the view path of observation port;
an air flow hose is attached to the steel flap;
a sight glass is provided at the outer side of air cooled observation port.

[0022] Accordingly, the air cooled observation port is mounted on the outer cover of the access door and in order to protect from 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.

[0023] An access door seal box and the access door assembly is mounted over which the observation door assembly is mounted. A cooling airline is provided which blows air into the furnace so that flue gas and radiant heat doesn’t blow on viewing side.

[0024] Thus, the new design ensures that we can have a combination of Access door with air cooled Observation door at a single location of boiler. This arrangement will work in locations of pressurized operation of steam generator zones. Thus the air cooled observation port mounted access door assembly has been conceived for utilization in pressurized steam generators.

[0025] The present invention is achieved by the features of principal claim and subsequent claims.

[0026] 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.

[0027] 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.

[0028] 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:

[0029] 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:

[0030] Figure 1 illustrates the elevation of existing assembly of access door.

[0031] Figure 2 illustrates the side view of the existing assembly of access door.

[0032] Figure 3 illustrates the plan of the existing assembly of air cooled observation door.

[0033] Figure 4 illustrates the elevation of proposed assembly of access door mounted with air cooled observation port.

[0034] Figure 5 illustrates the side view of proposed assembly of access door mounted with air cooled observation port.

[0035] Figure 6 illustrates the plan of the proposed access door mounted with air cooled observation port.

[0036] Figure 7 illustrates the assembly of Observation port that is mounted on Access door plate.

[0037] 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:

[0038] 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.

[0039] The present invention makes a disclosure regarding an assembly to use as single unit serving both for access during shut down and for observing pressurized locations of boiler while in operation.

[0040] The Present invention relates to the new design of access door and observation port assembly.

[0041] Now reference may be made to Figure-1 illustrating the elevation of the assembly of an access door having a cover plate (01). In order to strengthen the door cover plate (01) two stiffener plates (04) are provided. An access door handle (06) is attached to the cover plate (01) so that the access door can be opened by using the handle (06).

[0042] Now referring to Figure-2 illustrating the side view of the access door in which lug plates (02), (03), and (05) are attached to the door cover plate (01).

[0043] Now referring to Figure-3 illustrating the plan 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 (08) box and the whole door cover plate assembly is held together using screw, nut and washer kit (10).

[0044] Now referring to Figure-4, Figure-5 & Figure-6 illustrating the diagrams of new access door design of the present invention having an air cooled observation door assembly (Figure-7) mounted to its frame. The observation door assembly plate is attached to the access door frame at desired observation location using fasteners including screw, nut and washer kit (10). In order to get a complete view of the furnace inside, the refractory (08) is removed based on rectangular profile of view port through observation door. Steel anchors (09) are re positioned to hold refractory (08) with a view gap. A handle (11) is provided in observation port assembly. The handle (11) when moved downwards lifts the steel flap (12) located inside the view path. A sight glass (14) is provided at the outer side of air cooled observation port. An air hose (13) is also provided through which cooling air is flown into the steam generator to negate any gush of flue gas / heat due to pressurized operating conditions inside.

[0045] The access door is being used as entry and exit into the steam generator for maintenance during shut down and observation port for observing the working condition of the steam generator furnace. The access door and air cooled observation port are located in different locations based on the operation and maintenance requirements.

[0046] The new design can be provided at same opening location of furnace steam cooled walls. This combined door design can be located in a tube steam carrying tube wall.

[0047] The advantage of present Invention is that it can serve dual purpose of both access door during maintenance and observation port to view operation under pressurized conditions of a steam generator.

[0048] Another advantage of present Invention is that the openings in tubed wall surface can be reduced by having such a combination of access door and air cooled observation port.

[0049] Still another advantage of present Invention is that it can be utilized in pressurized zones of boiler operations.

[0050] 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.

WORKING OF THE INVENTION

The assembly can be operated both during furnace in operation and in shut down condition. In order have a look at what is happening inside the steam generator furnace, the operator can pull the port handle (11) which lifts the flap (12) made of material including Steel to view the furnace under operation using the sight glass (14). After the purpose of viewing the port handle (11) can be lifted up to its original position. The lug plate (03) of access door will be attached to the furnace seal box by using a number nut and bolt assembly (not shown) all around the lug plate (03). Under furnace shut down condition all the bolts and nuts that connect the lug plate (03) to seal box cover plate will be removed. The whole assembly of access door cum observation port can be removed in order provide access for personnel to move in and out of the furnace through the opening. Before starting the steam generation for operation these number of bolt and nuts are re fitted joining lug plate (03) and seal box.

[0051] 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.

[0052] 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.

[0053] 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”.

[0054] 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.

[0055] 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.

[0056] 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.

[0057] 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.