A device and method for feeding/welding terminal bend tubes in furnace side upper water wall panels used in high pressure steam generators

FIELD OF INVENTION
[001] The invention generally relates to the method of 5 manufacturing furnace side upper water wall panels in high pressure steam generators. More particularly, the invention relates to a device and method for feeding/welding terminal bend tubes in furnace side upper water wall panels used in high pressure steam generators. 10
BACKGROUND OF THE INVENTION
[002] Background description includes information that may be useful in understanding the present invention. It is not an 15 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 High pressure steam generators, water wall panels are one 20 of the important products. The water wall panels comprise of straight panels, gang bend panels and terminal bend panels (1). The terminal bend panels (1) form the furnace upper front walls and side walls of the high pressure steam generators. The terminal bend tubes consist of 90° bends (2) and offset bends (3 and 4). These 25 panels (1) are held in position at site by holding hanger rods (not shown) connected through the holes in the collector/connecting plates (6) welded to lug plates (5).
[004] In the conventional method of joint feeding in furnace side 30 upper water wall panels (1), a temporary fixture (8) is initially
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prepared as per the width of the particular panel (1) using tubes and angle plates. This fixture (8) is then welded to the particular panel (1). The 90° bends (2) and offset bends (3 and 4) are welded to the lug plates (5) with slots. Each individual terminal bend tube (2,3 and 4) is supported on the fixture (8) with the lug plate (5) and 5 then aligned and positioned to the required pitch manually before tacking.
[005] The critical dimensions to be maintained during the feeding of terminal bends are the distance (26) between 90° terminal bend 10 tubes (2) and offset terminal bend tubes (3), aligning bends with panel (1) and maintaining perpendicularity (Figure 3); the distance (27) between offset terminal bend tubes (3) and special offset terminal bend tubes (4) if any, aligning bend tubes with panel (1) and maintaining perpendicularity (Figure 4); individual pitch 15 between adjacent bend tubes (28) and overall centre to centre distance (29) between first and last terminal bend tubes (Figure 5); aligning all the lug plate slots, so that the holes in the collector plates (6) welded are in line (Figure 6).
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[006] In the existing method, chances of deviation from the dimensional requirement and the associated cycle time of joint feeding are high due to the manual setting of tubes by holding vertically upwards for maintaining individual as well as overall centre to centre distance. 25
[007] The drawbacks in the existing process are that the tube setting is time consuming, requiring more manpower for accurate setting; positioning the tubes by holding vertically upwards is difficult and prone to dimensional error. 30
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[008] Due to the above reasons, the tube feeding and the joint welded undergoes rework and increases the overall cycle time of manufacturing; the panel (1) before flipping for bottom half joint welding, has to be kept in a raised condition with the operator beneath the fixture (8) for cutting the supporting stands (7); hence 5 safety is a problem. For each panel (1), a temporary fixture (8) is to be prepared which is cut and scrapped after joint welding; hence involves wastage of resources.
[009] Hence, it is necessary to develop a device and method for 10 feeding the terminal bends (2,3 and 4) in furnace side upper water wall panels (1) of high pressure steam generators. The same has been introduced by the present invention, which can serve the purpose efficiently.
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OBJECTS OF THE INVENTION
[010] An object of the invention is to propose a device and method 20 for feeding/welding terminal bend tubes in furnace side upper water wall panels used in high pressure steam generators which obviates drawbacks of prior arts.
[011] Another object of the invention is to propose a device and 25 method for feeding/welding terminal bend tubes in furnace side upper water wall panels used in high pressure steam generators as per the required pitch dimensions.
[012] Still another object of the present invention is to provide a 30 device and method for feeding/welding terminal bend tubes in furnace side upper water wall panels used in high pressure steam generators which is to ensure good quality of joints.
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[013] Yet another object of the present invention is to provide a device and method for feeding/welding terminal bend tubes in furnace side upper water wall panels used in high pressure steam generators which is simple.
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[014] Further object of the present invention is to provide a device and method for feeding/welding terminal bend tubes in furnace side upper water wall panels used in high pressure steam generators in order to reduce the cycle time of manufacturing and the manpower involved in the joint feeding process. 10
[015] 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 15 form of the present invention is illustrated.
SUMMARY OF THE INVENTION
[016] One or more drawbacks of conventional systems and process 20 are overcome, and additional advantages are provided through the apparatus 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 25 considered to be part of the claimed disclosure.
[017] Accordingly, a device and method has been devised for terminal bend joint feeding in the furnace side upper water wall panels. The existing method requires additional manpower for 30 holding and setting the terminal bends vertically upwards and
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therefore is time consuming. Hence, the terminal bend feeding in this device is designed to set vertically downwards eliminating manual holding during setting.
[018] The new invented device can be moved to the chamfered end 5 of the panel using moving wheels in the device which is then lifted above the ground level to prevent further movement. The height of the device platform can be aligned to the chamfered end of the panel by the adjustable screw jacks provided at both sides. Scalloped plates of required pitch can be placed and clamped on the angle 10 plates provided on the device. The distance between the 90° bends and offset bends can be set in the device by suitably positioning the individual scalloped plates. Each terminal bend tube welded with lug plate can then be fed vertically downwards and arrested by butting the tube to the clamped scalloped plates, and the slot in the 15 lug plate to the lug plate guiding tube. Any mismatch observed during feeding can be corrected using a runner placed in a bend tube height adjustable track.
[019] Thus feeding and welding of terminal bends can be done with 20 less manpower and shorter cycle time, meeting all the critical dimensional requirements for the furnace side upper water wall panel fabrication.
[020] Various objects, features, aspects, and advantages of the 25 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.
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[021] 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.
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[022] 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. 10
BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS
[023] The illustrated embodiments of the subject matter will be best understood by reference to the drawings, wherein like parts 15 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:- 20
Figure 1 shows: The water wall panels with terminal bend tubes.
Figure 2 shows: The temporary fixture prepared for joint feeding as per the prior art.
Figure 3 shows: The distance between the 90° and offset terminal bends. 25
Figure 4 shows: The distance between the offset and special terminal bends if any.
Figure 5 shows: The individual distance between adjacent bend tubes and the total centre to centre distance between first and last terminal bends. 30
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Figure 6 shows: The distance to be maintained for aligning all the collector plates.
Figure 7 shows: A device and method for feeding/welding terminal bend tubes in furnace side upper water wall panels used in high pressure steam 5 generators according to present invention.
Figure 8 shows: The details of terminal bend adjustable locking sleeve mechanism of the present invention.
[024] The figures depict embodiments of the disclosure for purposes of illustration only. One skilled in the art will readily 10 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.
DETAIL DESCRIPTION OF THE PRESENT INVENTION WITH 15 REFERENCE TO THE ACCOMPANYING DRAWINGS OF PREFERRED EMBODIMENTS
[025] While the embodiments of the disclosure are subject to various modifications and alternative forms, specific embodiment 20 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 25 disclosure.
[026] The invention makes a disclosure regarding a technology pertinent to a device and method for feeding/welding terminal bend tubes in furnace side upper water wall panels used in high pressure 30 steam generators.
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[027] Now, reference may be made to Figure 7 indicating the details of the newly invented device (18). The device (18) comprises of five adjustable screw jacks (9), three in one end and two in other end, which aids in setting the height of the device platform exactly to that of the chamfered panel (1) ends. The three screw jacks (9) at one 5 end has got an additional function of holding the lug plate guiding tube (10) in position. Based on the slot width in the lug plates (5) welded to terminal bends (2,3 and 4), raw tube (10) of corresponding outer diameter can be placed on the three screw jacks (9).
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[028] The rigidity of the device (18) is ensured by the top (23) and bottom frames (24). Multitude of the moving wheels (11) are welded to the bottom frame (24) of the device (18), wherein a wheel (11) is placed at each end of the frame. The terminal bend width adjustable locking sleeve mechanism (as shown in Figure 8) is welded to the 15 supporting stands (19), which in turn is welded to the bottom frame (24) on both sides of the device (18). These sleeves (14) on either side, holds the angle plates (21,22) for clamping the scalloped plates (13). The sleeves (14) can be moved to the required position as per the dimensional requirement of terminal bends (2,3 and 4) and 20 locked in position using the locking screw thread (25). C-clamps (20) are provided on the angle plates (21,22) in order to arrest the scalloped plates (13) placed there over. One of the angle plates (21) is set at higher elevation than the other one. The angle plate set at higher elevation (21) is used to butt the straight portion of the offset 25 terminal bends (3) and position it, and the angle plate at lower elevation (22) is employed to butt and position the 90° terminal bends (2).
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[029] Now, the method for feeding/welding terminal bend tubes in furnace side upper water wall panels used in high pressure steam generators can be discussed hereinunder.
[030] The device (18) is moved to the chamfered end of the panel (1) 5 with the help of the moving wheels (11). Once placed in position, the moving wheels (11) can be lifted upwards from the ground level by rotating the wheel bolt (12) provided, so that the device (18) remains stationary on its self-weight throughout the joint feeding process. As per the design requirement of pitch dimension, two scalloped 10 plates (13) of corresponding pitch shall be placed on the angle plate supports (21,22) and clamped in position using C-clamps (20). The distance (26) between the 90° bends (2) and offset bends (3) is set in the device (18) by moving the terminal bend width adjustable locking sleeves (14) suitably. The sleeves (14) can be locked in 15 position once the dimension is set, using the locking screw thread (25).
[031] Each terminal bend tube (2,3 and 4) welded with lug plate (5) is to be placed on the device (18) towards downward position such 20 that the shop butt weld end of the terminal bend tube (2,3 and 4) rests on the side of the device (18) with two screw jacks (9) and the slot in the lug plate (5) welded, butts on the lug plate guiding tube (10) placed on the other side. Besides, the 90° (2) and offset terminal bends (3) placed alternately is arrested in position before tacking, 25 by butting to the corresponding scalloped plates (13) clamped at the angle plate supports (21,22) of the device (18).
[032] The two screw jacks (9) at one end of the device (18) holds a bend tube height adjustable track (15) with a runner (16). The 30
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purpose of this mechanism is to make fine adjustment in height of each individual tube (2,3 and 4) while feeding. During feeding of terminal bend tubes (2,3 and 4), if any slight mismatch is observed at the point of the butt joint for any particular tube, the runner (16) is to be moved along the bend tube height adjustable track (15) 5 exactly to the bottom of the particular tube and then to be raised suitably by rotating the runner thread screw (17) provided, so that proper matching can be ensured before tacking.
[033] Once the tacking of all 90° (2) and offset terminal bends (3) 10 are done, half root TIG welding can be carried out in the locked position of the device (18), thereby avoiding any deviation from the initial set position during welding. If any special offset terminal bend tube (4) is to be welded, soon after completing the half root TIG welding of all the 90° (2) and offset terminal bend tubes (3), one of 15 the scalloped plates (13) position can be adjusted as per the dimensional requirement by moving and locking the terminal bend width adjustable locking sleeves (14) suitably. The special offset terminal bend tube (4) welded with lug plate (5) can then be placed and arrested in position as per the above mentioned procedure and 20 to be proceeded for tacking and half root TIG welding.
[034] On completion of the half root TIG welding of all the terminal bend tubes (2,3 and 4), the panel (1) can be raised slightly and the device (18) can be released from position by lowering the moving 25 wheels (11) to the ground level followed by moving off the panel (1).
[035] 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 30
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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. 5
[036] 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 10 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 15 appended claims.
Advantageous Features
- the cycle time of panel fabrication,
- Ensures the dimensional accuracy, 20
- Improves the welding quality,
- Reduces the manpower required for joint feeding operation and also ensures safe working.
[037] It will be understood by those within the art that, in general, terms used herein, and especially in the appended claims (e.g., 25 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
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“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 5 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 10 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 15 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 20 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 25 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 30
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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 5 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 10 possibilities of “A” or “B” or “A and B”.
[038] 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 15 developed designs and materials should be employed. Those in the art are capable of choosing suitable manufacturing and design details.
[039] The terminology used herein is for the purpose of describing 20 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 frnctions, or alternatives thereof, may be combined into other systems or applications. Various presently unforeseen or unanticipated alternatives, 25 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.
[040] 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, 5 may arise from applicants/patentees and others.
[041] 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 10 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:

1) A device for feeding/welding terminal bend tubes (2,3,4) in furnace side upper water wall panels (1) comprising:
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a top (23) and bottom frame (24) with a plurality of adjustable screw jacks (9) adjoined thereto for setting the height of the device platform to that of the chamfered panel (1) ends and holding lug plate guiding tube (10) in position;
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multitude of moving wheels (11) placed at the bottom frame (24) to lift upward and downward;
terminal bend width adjustable locking sleeve is connected to the bottom frame (24) on both sides, wherein the sleeves (14) 15 on either side holds angle plates (21, 22) for clamping the scalloped plates (13) positioned between the top (23) and bottom frame (24); in which bend tube height adjustable track (15) with runner (16) for avoiding individual joint mismatch is placed on one side between two screw jacks (9). 20
2. The device for feeding/welding terminal bend tubes (2,3,4) in furnace side upper water wall panels as claimed in claim 1, wherein the raw tube (10) of corresponding outer diameter is placed on multiple screw jacks (9) on one side based on the 25 slot width in the lug plates (5) fixedly secured to terminal bends (2,3,4).
3. The device for feeding/welding terminal bend tubes (2,3,4) in furnace side upper water wall panels as claimed in claim 1 or 30 2, wherein the adjustable locking sleeve (14) is welded to
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supporting stand (19), which is connected to the bottom frame (24) on both sides.
4. The device for feeding/welding terminal bend tubes (2,3,4) in furnace side upper water wall panels as claimed in claims 1-5 3, wherein the sleeves (14) are adjusted to the required position as per the dimensional requirement of terminal bends (2, 3 and 4) and locked in position using the locking screw thread (25).
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5. The device for feeding/welding terminal bend tubes (2,3,4) in furnace side upper water wall panels as claimed in claim 1-4, wherein the angle plate set at higher elevation (21) is used to butt the straight portion of the offset terminal bends (3) and position it, and the angle plate at lower elevation (22) is 15 employed to butt and position the 90° terminal bends (2).
6. A method for feeding/welding terminal bend tubes (2,3,4) in furnace side upper water wall panels (1) using the device as claimed in claim 1, comprising steps of:- 20
- moving the device (18) towards the panel (1) by the moving wheels (11) for keeping the device stationary,
- clamping the scalloped plates (13) of particular pitch to the angle plate supports (21, 22) for maintaining the individual 25 (28) and center to center distance (29) of the tubes (10),
- setting of distance (26) between 90° (2) and offset terminal bends (3) and offset bends (4) if any (27) with the help of the adjustable locking sleeves (14),
- aligning the lug plate slots by the lug plate guiding tube (10), 30
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- Avoiding joint mismatch during individual tube feeding using the bend tube height adjustable track (15) together with runner (16).
7. The method for feeding/welding terminal bend tubes (2,3,4) 5 in furnace side upper water wall panels as claimed in claim 6, wherein the sleeves (14) can be locked in position once the dimension is set, using the locking screw thread (25).
8. The method for feeding/welding terminal bend tubes (2,3,4) 10 in furnace side upper water wall panels as claimed in the claims 1-7, wherein each terminal bend tube (2, 3 and 4) welded with lug plate (5) is to be placed on the device (18) towards downward position such that the shop butt weld end of the terminal bend tube (2, 3 and 4) rests on the side of the 15 device (18) with two screw jacks (9) and the slot in the lug plate (5) welded, butts on the lug plate guiding tube (10) placed on the other side, wherein once the tacking of all 90° (2) and offset terminal bends (3) are done, half root TIG welding can be carried out in the locked position of the device 20 (18), thereby avoiding any deviation from the initial set position during welding.
9. The method for feeding/welding terminal bend tubes (2,3,4) in furnace side upper water wall panels as claimed in claims 25 1-8, wherein if any special offset terminal bend tube (4) is to be welded, soon after completing the half root TIG welding of all the 90° (2) and offset terminal bend tubes (3), one of the scalloped plates (13) position can be adjusted as per the
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dimensional requirement by moving and locking the terminal bend width adjustable locking sleeves (14) suitably.
10. The method for feeding/welding terminal bend tubes (2,3,4) in furnace side upper water wall panels as claimed in claims 5 1-9, wherein the special offset terminal bend tube (4) welded with lug plate (5) can then be placed and arrested in position as per the procedure and to be proceeded for tacking and half root TIG welding.