, Description:AN APPARATUS FOR FABRICATION OF HANGER TUBES OR COILS
FIELD OF INVENTION
[001] The present subject matter described herein, relates to an apparatus for fabrication of tubes used in high temperature and high-pressure applications. More particularly, to an apparatus for fabrication of hanger tubes and fit up of lug plate with bearing plate for hanger tubes of coils.
BACKGROUND AND PRIOR ART AND PROBLEM IN PRIOR ART
[002] In power plants, hanger tubes are used for carrying load of economizer coils and super heater coil. These hanger tubes are located in second pass of supercritical boiler. The Hanger tubes have a length in the range 15 - 22 meters. One end of hanger tube is straight end whereas other end is profile of two bends with arm length of 300 mm to 400 mm. One end of hanger tube is connected with intermediate header while another end to an outlet header. These hanger tubes must bend accurately so that lug plate and bearing plate can be welded accurately. A Bearing plate is a rectangular plate with hole, whereas a lug plate is profile plate having the same diameter of as the hole of the rectangular plate. While fit up of two numbers bearing plate on each side of lug plate, it has to be ensured that holes should coincide. These holes are provided for lifting purposes. Once the fit up is completed full welding may be carried out with lug plate and bearing plate. Afterwards the welded piece may be welded with hanger tubes. These completed hanger tubes undergo stress relieving and further sent to industrial sites.
[003] For one supercritical boiler approx. a hundred hanger tubes are required. Manual fit up of bearing plate with lug plate requires more work force and demands more time. Apart from these, rework is generated, which is not desirable. Hence, there arises a need for a safe and simple apparatus based on a process for carrying out the fit up of lug plate with bearing plates to ensure reduced cycle time and high accuracy.

OBJECTS OF THE INVENTION
[004] It is therefore the object of the invention to overcome the aforementioned and other drawbacks in prior art.
[001] The principal objective of the present invention is to provide for an apparatus for carrying out fabrication of tubes or coils with reduced cycle time and high accuracy.
[005] Another object of the present invention is to improve the fit up of lug plate with bearing plate for hanger tubes of coils.
[002] Another object of the present invention is to reduce the rework generated during the fabrication process.
[003] Another object of the present invention is to provide for a safe and efficient process to carry out the fabrication of tubes or coils and fit up of lug plate with bearing plate for hanger tubes or coils.
[004] These and other objects and advantages of the present subject matter would be apparent to a person skilled in the art after consideration of the following detailed description taken into consideration with accompanying drawings in which preferred embodiments of the present subject matter are illustrated.
SUMMARY OF THE INVENTION
[005] One or more drawbacks of the conventional technology based on existing apparatus and processes are overcome, and additional advantages are provided through a novel apparatus for fabrication of hanger tubes or coils 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 a part of the claimed disclosure.
[006] In an embodiment of the present subject matter, an apparatus for fabrication of hanger tubes or coils, the apparatus comprising a vertical support channel, a horizontal support channel connected at an angle of 90o with the vertical support channel, a cylindrical guide with a central threaded hole, a locking unit welded to a screw nut, an inner guide plate, a support unit, a lug plate, and a pair of bearing plates wherein, the locking unit is fit into the screw nut inside the guide, the inner guide plate is welded to the vertical support channel, wherein the height measured from top of the inner guide plate to the centre of the guide is equal to height measured from the base of the bearing plate up to the centre part of hole of the bearing plate, and the support unit is welded on the base of the horizontal channel.
[007] In another embodiment of the present subject matter, the length between the top of the vertical channel and the support unit is equal to the sum of thickness of inner bearing plate and thickness of lug plate.
[008] In another embodiment of the present subject matter, the bearing plates comprise of an inner bearing plate and an outer bearing plate.
[009] In another embodiment of the present subject matter, a process for fabrication of hanger tubes or coils based on the apparatus claimed in claim 1, the process comprising inserting the inner bearing plate into the cylindrical guide wherein, the base of the inner bearing plate is in contact with the top portion of the inner guide plate supporting the inner bearing plate, inserting the lug plate into the cylindrical guide wherein, the lug plate is covered by the inner bearing plate, with the base of the lug plate on the horizontal support channel, inserting the outer bearing plate into the cylindrical guide with no gap between the outer bearing plate, lug plate and inner bearing plate, tightening the locking unit and screw nut inside the central threaded hole of the cylindrical guide wherein, the bearing plates and lug plate are locked, tacking the bearing plates with the lug plate at four portions on the surface of the outer bearing plate, welding the tacked bearing plates with the lug plate and welding the lug plate on the top of hanger tube.
[0010] In another embodiment of the present subject matter, the structural profile of the hanger tube is similar to the structural profile of the lug plate.
[0011] In another embodiment of the present subject matter, the bearing plates are locked with the lug plate by rotating the locking unit and screw nut inside the cylindrical guide.
[0012] 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.
[0013] 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 DRAWINGS
[0014] 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:
[0015] Figure 1a illustrates a schematic front view of the apparatus in accordance with the present subject matter;
[0016] Figure 1b illustrates a schematic side view of the apparatus in accordance with the present subject matter;
[0017] Figure 2 to 5 illustrates a view of the process in accordance with the present subject matter;
[0018] The figures depict embodiments of the present subject matter for the purposes of illustration only. A person skilled in the art will easily 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
[0019] The detailed description of various exemplary embodiments of the disclosure is described herein with reference to the accompanying drawings. It should be noted that the embodiments are described herein in such details as to clearly communicate the disclosure. However, the amount of details provided herein are not intended to limit the anticipated variations of embodiments; on the contrary, the intention is to cover all modifications, equivalents, and alternatives falling within the scope of the present disclosure as defined by the appended claims.
[0020] It is also to be understood that various arrangements may be devised that, although not explicitly described or shown herein, embody the principles of the present disclosure. Moreover, all statements herein reciting principles, aspects, and embodiments of the present disclosure, as well as specific examples, are intended to encompass equivalents thereof.
[0021] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of example embodiments. As used herein, the singular forms “a",” “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises,” “comprising,” “includes” and/or “including,” when used herein, specify the presence of stated features, integers, steps, operations, elements and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components and/or groups thereof.
[0022] It should also be noted that in some alternative implementations, the functions/acts noted may occur out of the order noted in the figures. For example, two figures shown in succession may, in fact, be executed concurrently or may sometimes be executed in the reverse order, depending upon the functionality/acts involved.
[0023] Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which example embodiments belong. It will be further understood that terms, e.g., those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and will not be interpreted in an idealized or overly formal sense unless expressly so defined herein.
[0024] These and other advantages of the present subject matter would be described in greater detail with reference to the following figures. It should be noted that the description merely illustrates the principles of the present subject matter. It will thus be appreciated that those skilled in the art will be able to devise various arrangements that, although not explicitly described herein, embody the principles of the present subject matter and are included within its scope.
[0025] The present subject matter describes an apparatus and a process for fabrication of hanger tubes and fit up of lug plate with bearing plate for hanger tubes of coils.
[006] As illustrated in Figure 1a and Figure 1b, the present subject matter discloses an apparatus 100 or fabrication of hanger tubes 110 or coils 110 and a process for fitting of a lug plate 108 with bearing plates 199a, 109b for hanger tubes of coils.
[0026] In accordance with an embodiment of the present subject matter, disclosed herein is an apparatus for fabrication of hanger tubes or coils. The apparatus comprising a vertical support channel 101, a horizontal support channel 102 connected at an angle of 90o with the vertical support channel, a cylindrical guide 103 with a central threaded hole, a locking unit 104 welded to a screw nut 105, an inner guide plate 106, a support unit 107, a lug plate 108 and a pair of bearing plates 109a, 109b wherein, the locking unit 104 is fit into the screw nut 105 inside the guide 103, the inner guide plate 106 is welded to the vertical support channel 101, wherein the height measured from top of the inner guide plate 106 to the centre of the guide 103 is equal to height measured from the base of the bearing plate 109 up to the centre part of hole of the bearing plate 109, and the support unit 107 is welded on the base of the horizontal channel 102. Further, the length between the top of the vertical channel 101 and the support unit 107 is equal to the sum of thickness of inner bearing plate 109a and thickness of lug plate 108. In addition, the bearing plates 109a, 109b are in form of an inner bearing plate 109a and an outer bearing plate 109b.
[0027] The present subject matter discloses a process for fabrication of hanger tubes 110 or coils 110 and fitting of the lug plate 108 into the bearing plates 109a, 109b followed by welding of the set-up. The process comprises the following steps such as inserting the inner bearing plate 109a into the cylindrical guide 103 wherein, the base of the inner bearing plate 109a is in contact with the top portion of the inner guide plate 106 supporting the inner bearing plate 109a, inserting the lug plate 108 into the cylindrical guide 103 wherein, the lug plate 108 is covered by the inner bearing plate 109a, with the base of the lug plate 108 on the horizontal support channel 102, inserting the outer bearing plate 109b into the cylindrical guide 103 with no gap between the outer bearing plate 109b, lug plate 108 and inner bearing plate 109a, tightening the locking unit 104 and screw nut 105 inside the central threaded hole of the cylindrical guide 103 wherein, the bearing plates 109a, 109b and lug plate 108 are locked, tacking the bearing plates 109a, 109b with the lug plate 108 at four portions on the surface of the outer bearing plate 109b, welding the tacked bearing plates 109a, 109b with the lug plate 108 and welding the lug plate 108 on the top of hanger tube 110.
[0028] During the fitting of lug plate 108 into the bearing plates 109a, 109b, the bearing plates 109a, 109b are locked with the lug plate 108 by rotating the locking unit 104 and screw nut 105 inside the cylindrical guide 103 and it becomes important that the structural profile of the hanger tube 110 should be similar to the structural profile of the lug plate 108.
[0029] 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 particular 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). 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.”
[0030] It will be further appreciated that functions or structures of a plurality of components or steps may be combined into a single component or step, or the functions or structures of one-step or component may be split among plural steps or components. The present invention contemplates all of these combinations. Unless stated otherwise, dimensions and geometries of the various structures depicted herein are not intended to be restrictive of the invention, and other dimensions or geometries are possible. In addition, while a feature of the present invention may have been described in the context of only one of the illustrated embodiments, such feature may be combined with one or more other features of other embodiments, for any given application. It will also be appreciated from the above that the fabrication of the unique structures herein and the operation thereof also constitute methods in accordance with the present invention. The present invention also encompasses intermediate and end products resulting from the practice of the methods herein. The use of “comprising” or “including” also contemplates embodiments that “consist essentially of” or “consist of” the recited feature.
[0031] Although embodiments for the present subject matter have been described in language specific to structural features, it is to be understood that the present subject matter is not necessarily limited to the specific features described. Rather, the specific features and methods are disclosed as embodiments for the present subject matter. Numerous modifications and adaptations of the system/component of the present invention will be apparent to those skilled in the art, and thus it is intended by the appended claims to cover all such modifications and adaptations, which fall within the scope of the present subject matter.
[0032] Reference Numerals:
Reference Numerals Description
100 Apparatus
101 Vertical Support Channel
102 Horizontal Support Channel
103 Cylindrical Guide
104 Screw Nut
105 Locking Unit
106 Inner Guide Plate
107 Support Unit
108 Lug Plate
109a Inner Bearing Plate
109b Outer Bearing Plate
110 Hanger Tube

Claims:We Claim:
1. An apparatus for fabrication of hanger tubes or coils, the apparatus comprising:
a vertical support channel (101);
a horizontal support channel (102) connected at an angle of 90o with the vertical support channel;
a cylindrical guide (103) with a central threaded hole;
a locking unit (104) welded to a screw nut (105);
an inner guide plate (106);
a support unit (107);
a lug plate (108); and
a pair of bearing plates (109a, 109b);
wherein,
the locking unit (104) is fit into the screw nut (105) inside the guide (103),
the inner guide plate (106) is welded to the vertical support channel (101), wherein the height measured from top of the inner guide plate (106) to the centre of the guide (103) is equal to height measured from the base of the bearing plate (109) up to the centre part of hole of the bearing plate (109),
and the support unit (107) is welded on the base of the horizontal channel (102).
2. The apparatus as claimed in claim 1, wherein the length between the top of the vertical channel (101) and the support unit (107) is equal to the sum of thickness of inner bearing plate (109a) and thickness of lug plate (108).
3. The apparatus as claimed in claim 1, wherein the bearing plates (109a, 109b) comprise of an inner bearing plate (109a) and an outer bearing plate (109b).
4. A process for fabrication of hanger tubes or coils based on the apparatus (100) claimed in claim 1, the process comprising :
inserting the inner bearing plate (109a) into the cylindrical guide (103) wherein, the base of the inner bearing plate (109a) is in contact with the top portion of the inner guide plate (106) supporting the inner bearing plate (109a);
inserting the lug plate (108) into the cylindrical guide (103) wherein, the lug plate (108) is covered by the inner bearing plate (109a), with the base of the lug plate (108) on the horizontal support channel (102);
inserting the outer bearing plate (109b) into the cylindrical guide (103) with no gap between the outer bearing plate (109b), lug plate (108) and inner bearing plate(109a);
tightening the locking unit (104) and screw nut (105) inside the central threaded hole of the cylindrical guide (103) wherein, the bearing plates (109a, 109b) and lug plate (108) are locked;
tacking the bearing plates (109a, 109b) with the lug plate (108) at four portions on the surface of the outer bearing plate (109b);
welding the tacked bearing plates (109a, 109b) with the lug plate (108); and
welding the lug plate (108) on the top of hanger tube (110).
5. The process as claimed in claim 4, wherein the structural profile of the hanger tube (110) is similar to the structural profile of the lug plate (108).
6. The process as claimed in claim 4, wherein the bearing plates (109a, 109b) are locked with the lug plate (108) by rotating the locking unit (104) and screw nut (105) inside the cylindrical guide (103).