FIELD OF THE INVENTION
The present invention relates to a method and a holding apparatus for holding an elbow, a reducer and a tee joint pipe horizontally in order to reduce cycle time and number of activities required for butt welding at inaccessible segments.
BACKGROUND OF THE INVENTION
A boiler is a steam generator which is used to generate steam by applying heat energy to water. A typical once through super critical (OTSC) 600 MW boiler weighs around 14000 tons in which the weight of pressure parts is 6000 tons. In the present invention, the pressure parts are lines and links which contribute 1850 tons to the boiler weight. The maximum working temperature and pressure of these lines and links is 566.80 Centigrade and 281.2 kg/sq.cm respectively. The lines and links form the circulation system of the boiler. They are provided to connect different assemblies in the boiler and carry fuel, water, steam, vapour or mixture of any of these across the system. Pipes with various outer diameter (OD) size 219, 273, 323, 368, 406, 457, 508, 558, 610, 660, 711, and 762 mm and thickness ranging from 40 mm to 105 mm are used in the lines and links. The different configuration of the jobs includes pipe with pipe, and pipe with fittings.
Generally, during a butt joint welding, the pre-heat temperature is 2200 Centigrade and the inter-pass temperature is 3500 Centigrade. The post weld heat treatment (PWHT) or stress relieving (SR) is performed at 7600±100 Centigrade. These pipes are joined with fittings for the compact arrangement of the circulation system of the boiler. The fittings are elbows, reducers, tee joint pipes and pipes having the same outer diameter and thickness as that of the joining pipe. The fittings are joined with pipe through butt joint fit up and butt joint welding. The butt joint welding of lines and links pipe has three phases. The root welding is carried out by manual gas tungsten arc welding (GTAW). After completion of welding of one half, the job is rotated for completion of the second half of root welding. Subsequently, two to three layers of shielded metal arc welding (SMAW) is accomplished to avoid burn through and to provide adequate strength.
Presently, a pipe to be joined with the elbow is positioned in a surface plate and grinding is carried out on its surface which will come in contact with the elbow. Then it is checked for square defects and parallelism. The elbow which is to be joined is welded with bridge plate for firmness which rests on the surface plate. Then the pipe and the

elbow are aligned and placed at an exact root gap for the butt joint welding. Here the setup i.e. the pipe and the elbow are held together firmly by welding the bridge plates at least in two or three places over the periphery of the job to maintain the required gap. Similarly, a pipe to be joined with the reducer is positioned in the surface plate and grinding is carried out on its surface which will come in contact with the reducer followed by verification for square and parallelism. The reducer which is to be joined is welded with bridge plate for firmness that rests on the surface plate. Then the pipe and the reducer are aligned and placed at an exact root gap for welding. This setup i.e. the pipe and the reducer are held together firmly by welding the bridge plates holding them together at least in two or three places over the periphery of the job for maintaining the required gap. Then these joints i.e. pipe with elbow fit-up or pipe with reducer are welded by the welders climbing over the surface plate in an inconvenient position. Welding of these joints takes place in multi stage i.e. joining at root by tungsten inert gas (TIG) welding, followed by several passes of sheet metal arc welding (SMAW) welding till required throat thickness is obtained.
Further, access to the root of the joint is hindered by the presence of bridge plates which are welded over the circumference of the fit up. As fit up is placed over the flat surface (on surface plate), a portion of the arc of the joint fit up is not accessible for welding. Welders need to crawl over the visible periphery of the joint fit up to complete the welding in several pass. To carry out the welding at inaccessible segment of joint fit-up, the heavy pipe is rotated with the help of crowbar to get the leverage advantage. Rotating of heavy pipe fit-up by fitters leads to more fatigue. Additionally, the welding of the joints in an awkward position for several passes over a significant period of time to complete the joint results in fatigue to the welders which in turn leads to rework and repair. Further routine welding of these type of joints by the welders over a period of time leads them to health issues like back pain, spinal chord deterioration etc. Moreover, frequent lifting and movement of pipes and welding in various awkward postures over the surface of the plate is potential accident hazard which is a cause of concern from safety point of view.
On completion of welding, the bridge pieces are to be removed by hammering. After removal, the pieces where bridge pieces were held, are to be ground. Then these surfaces need to be heated and material to be re-built up by welding. Finally, these

surfaces are further subjected to liquid penetrant inspection (LPI) to verify for any surface defects.
One of the inherent limitation of conventional method for connecting different diameter pipes using reducer or elbow is that the set up required to carry out a continuous and a flawless welding is a cumbersome operation. Heavy alloy steel pipes and forged alloy steel fittings are supported on surface plates. The bridge plate stiffeners which are welded to ensure the alignment of pipe with reducer or elbow also hinders the welding process. Further, welding below the surface resting on the surface plate is also not accessible. Additionally, the welding torch also could not reach below the bridge plate stiffeners. Also, the bridge plate stiffeners which are welded with the surface table are to be broken and grinding has to be performed. Bridge pieces which are welded initially to keep both the pipe and reducer in aligned position are to be removed by hammering and then further rework like grinding, pre-heating, material built up have to be performed; followed by liquid penetrant inspection (LPI).
Further, the workers are exposed to hazardous situation and injuries due to prolonged discomfort and pain. These occupational risk factors are the most common entity to cause health problems which adversely affect the worker productivity and work quality. Generally, the injuries like musculoskeletal disorders develop gradually over a period of weeks, months and years.
Thus, the traditional methods for connecting pipes with different diameters by butt welding are time consuming procedures which involve more usage of crane, more manpower requirement having large cycle time. In addition, the welding at inaccessible surfaces poses a potential safety hazard in the workplace. Further, these methods require various reworks and processes for post welding surface preparation and post welding surface verification thereby making them energy intensive and uneconomical.
Hence, there is a need to develop a method for holding a job along horizontal axis, to avoid the elbow, reducer etc. being held on surface plate as well as to facilitate easy fit up process by removing the requirement of addition of bridge pieces and related reworks, which would provide ergonomically better working conditions to employees by avoiding occupational health vulnerabilities.

OBJECTS OF THE INVENTION
It is therefore an object of the present invention to solve the aforementioned and other drawbacks existing in the conventional process of holding pipes with different diameters for butt welding.
A primary object of the present invention is to provide a method for holding a job horizontally in order to facilitate easy fit up for butt welding at inaccessible segments.
Another object of the present invention is to develop a holding apparatus for positioning of a job to carry out a welding process in a manageable, convenient manner.
Yet another object of the present invention is to provide a method to reduce work cycle time by avoiding post welding surface preparation and post welding surface verification.
Still another object of the present invention is to provide a method for an easy job set up.
Yet another object of the present invention is to avoid occurrence of potential accident hazards during welding of inaccessible segments of a job.
Still another object of the present invention is to cut down the number of activities involved and to increase the output.
Yet another object of the present invention is to diminish workforce fatigue and to decrease crane dependency.
Still another object of the present invention is to provide an energy-efficient and cost-effective method of carrying out welding.
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
One or more drawbacks of conventional arts for holding a job in order to facilitate easy fit up for butt welding at inaccessible segments are overcome, and additional advantages are provided through the present invention as disclosed. 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.

In an embodiment, the present invention provides a method of holding a pipe (elbow, reducer or tee joint) of various sizes over a range of diameters which can be aligned axially over the other pipe to be welded.
In another embodiment, the present invention facilitates an easy fit up process for welding purposes. A vee block is provided at the top of the top face plate along its one side to accommodate the pipes of different diameters. Pitch holes are provided at the bottom of the job positioners for adjusting the diameter between the job positioners to accommodate the elbows, reducers and tee pipe fittings of different diameters. Job height adjustment screw rod moves the vee block up and down through box nut when handle is rotated. Top rib plates are provided at the bottom of the top face plate for extra strength. This entire structure is placed upon mechanical jack screw which can be moved up and down by lifting adjustment wheel. Bottom rib plates are attached to bottom face plate for better rigidity.
In another embodiment, the present invention provides a method for obtaining the correct axial alignment with the pipe to be welded. Job lifting wedge is provided for adjustment thereby getting precise alignment of elbow, reducer or tee joint pipe with the pipe to be welded.
Various objects, features, aspects and advantages of the present invention will become apparent to those skilled in the art from the following detailed description when taken in conjunction with the accompanying drawings in which like parts are designated by like numerals.
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.
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
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 holding apparatus that are consistent with the subject matter as claimed herein, wherein:
Fig. 1 illustrates an isometric view of a holding apparatus to carry out the fit up and butt welding of elbows, reducers, tee joint pipes and different sizes of pipes in accordance with an embodiment of the present invention.
Fig. 2 illustrates a cross sectional isometric view of the holding apparatus along A-A in accordance with an embodiment of the present invention.
Fig. 3 illustrates a front view of the holding apparatus in accordance with an embodiment of the present invention.
Fig. 4 illustrates an isometric view of an elbow to pipe fit up using the holding apparatus in accordance with an embodiment of the present invention.
Fig. 5 illustrates a side isometric view of the elbow to pipe fit up using the holding apparatus in accordance with an embodiment of the present invention.
Fig. 6 illustrates a front view of the elbow to pipe fit up using the holding apparatus in accordance with an embodiment of the present invention.
Fig. 7 illustrates a top view of the elbow to pipe fit up using the holding apparatus in accordance with an embodiment of the present invention.
Fig. 8 illustrates an isometric view of a reducer to pipe fit up using the holding apparatus in accordance with an embodiment of the present invention.
Fig. 9 illustrates a front view of the reducer to pipe fit up using the holding apparatus in accordance with an embodiment of the present invention.
Fig. 10 illustrates an isometric view of a tee joint pipe to pipe fit up using the holding apparatus in accordance with an embodiment of the present invention.
Fig. 11 illustrates a front view of the tee joint pipe to pipe fit up using developed holding apparatus in accordance with an embodiment of the present invention.
Fig. 12 illustrates an isometric view of a pipe to pipe fit up using developed holding apparatus in accordance with an embodiment of the present invention.
Fig. 13 illustrates a front view of the pipe to pipe fit up using developed holding apparatus in accordance with an embodiment of the present invention.
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 THE INVENTION
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.
The drawings illustrate only those specific details that are pertinent to understand the embodiments of the present disclosure, so as not to obscure the disclosure with details that will be clear to those of ordinary skill in the art having benefit of the description herein.
Figure 1 illustrates an isometric view of a holding apparatus to carry out the fit up and butt welding of elbows, reducers, tee joint pipes and different sizes of pipes in accordance with an embodiment of the present invention. In the present invention, a vee block (1) is provided at the top of a top face plate (12) along its one side to accommodate the pipes of different diameters. Two job positioners (2) are provided along two edges of the top face plate (12). One job positioner (2) is placed opposite to the vee block (1) and another job positioner (2) is placed adjacent to the vee block (1). A number of pitch holes (3) are provided at the bottom of the job positioners (2) for adjusting the diameter between the job positioners (2) to accommodate different diameters of elbows, reducers, tee pipe fittings. The job positioners (2) can be locked in desired position with the help of a pair of job positioners holding bolt and nut (4). A job lifting wedge (5) is provided at the other side of the top face plate (12). The job lifting wedge (5) is attached to a screw rod (6) and connected to a handle (8). The screw rod (6) of the job lifting wedge (5) moves in forward and backward directions through a box nut (7). The vee block (1) is attached to a job height adjustment screw rod (10) which is also connected to a handle (11). A set of bottom rib plates (17) are attached to a bottom face plate (18) for better rigidity. Four metallic wheels (19) are provided at the four corners of the bottom face plate (18) and are fastened by a number of wheel mounting bolt and nuts (20). The metallic wheels (19) can be rotated through 3600. This entire assembly can be locked in

any position with the help of a movement locking unit (21) which is attached to the bottom face plate (18) with the help of a lock screw (22).
Figure 2 illustrates a cross sectional isometric view of the holding apparatus along A-A in accordance with an embodiment of the present invention. The holding apparatus has a mechanical jack screw (14) whose movement is controlled by a lifting adjustment wheel (16). Further, a number of dowel pins (15) are provided to restrict the movement of the structure. Further, the height of a top face plate (12) can be altered with the help of the mechanical jack screw (14) and lifting adjustment wheel (16).
Figure 3 illustrates a front view of the holding apparatus in accordance with an embodiment of the present invention. In the present invention, a job height adjustment screw rod (10) is provided which facilitates the upward and downward movement of a vee block (1) through a box nut (9) when a handle (11) is rotated. Further, a number of top rib plates (13) are provided at the bottom of a top face plate (12). This entire structure is placed upon a mechanical jack screw (14) which is moved upward and downward by a lifting adjustment wheel (16). Upward movement of structure through the mechanical jack screw (14) is restricted by a number of dowel pins (15). This entire mechanism is placed on a bottom face plate (18). Additionally, the vee block (1) can be moved along y axis i.e. in vertical direction with the help of the box nut (9), the job height adjustment screw rod (10) and the handle (11). Further, a job lifting wedge (5) can be moved along x axis i.e. in horizontal axis to align the elbow pipe fittings and to adjust the tee joint pipe fittings accurately. The top rib plates (13) and the bottom rib plates (17) are provided for extra strength. Four Metallic wheels (19) which can be rotated through 3600 are fixed at the bottom of a bottom face plate (18) and enables to move to desired place easily. A movement locking unit (21) helps to lock the entire unit firmly at any point during the joining operation.
Figures 4 to 7 illustrate an isometric view, a side isometric view, a front view and a top view of an elbow (24) to pipe fit up using the holding apparatus respectively in accordance with the embodiments of the present invention. In this set up, the elbow (24) is positioned over the holding apparatus (23) and a pipe to be welded (28) is held by a roller support (29) for welding purpose. Here, the roller support (29) is a fixture configured with two rollers at the top to rotate the pipe (28) to weld uniformly. Referring to figure 1 and 5, it can be observed that the elbow (24) pipe joint is placed over two job

positioners (2) of the holding apparatus (23). Normally forged elbows are being received whose end sections are to be machined accurately before welding with the other pipe. But the outer surfaces and periphery of these elbows are uneven, as a result they do not align correctly with the pipe to be welded. In order to get the correct axial alignment with the pipe to be welded, a job lifting wedge (5) is provided as shown in figure 1. Using this component of the holding apparatus (23), a precise alignment of the elbow (24) with the pipe to be welded (28) can be achieved. Figure 7 illustrates that one end of the elbow (24) which has to be welded with the pipe (28), is placed over the job positioner which is provided opposite to the vee block (1). The other non-wieldable end is placed over the job positioner provided adjacent to the vee block (1).
Figures 8 and 9 illustrate an isometric view and a front view of a reducer (25) to pipe fit up using the holding apparatus respectively in accordance with the embodiments of the present invention. Referring to the figures 1 and 8, the reducer (25) has to be positioned over a vee block (1) and a job positioner (2) opposite to the vee block (1) of a holding apparatus (23). And a pipe to be welded (28) is placed over a roller support (29) which is configured with two rollers at the top to rotate the pipe (28) to weld uniformly. Axial alignment of the reducer (25) can be obtained by moving the vee block
(1) vertically with the help of the job height adjustment screw rod (10) and the box nut
(9) attached to it as shown in figure 1. In figure 9, one end of the reducer (25) which
has to be welded with the pipe (28), is placed over the job positioner which is provided
opposite to the vee block (1) and the other non- wieldable end is placed over the vee
block (1).
Figures 10 and 11 illustrate an isometric view and a front view of a tee joint pipe (26) to pipe fit up using the holding apparatus respectively in accordance with the embodiments of the present invention. Tee pipes (26) are located over the job positioners
(2) and the job lifting wedge (5). In the present invention, the job lifting wedge (5) can
be moved along x axis i.e. in horizontal axis to align the tee joint pipe (26) pipe fittings
accurately. From figures 10 and 11, it can be observed that the wieldable end of the tee
joint pipe (26) is mounted on the job positioner provided opposite to the vee block (1).
And, one of two non- wieldable ends is placed over the job positioner provided adjacent
to the vee block (1).
Figures 12 and 13 illustrate an isometric view and a front view of a pipe (27) to pipe fit up using developed holding apparatus in accordance with an embodiment of the

present invention. The set up for welding of pipes are different from those of elbow, reducer and tee joint pipe. For the welding of pipes, wieldable ends of pipes are placed over the holding apparatus (23) and non- wieldable ends on the roller supports (29). Each of the roller supports (29) is provided with two rollers at the top to rotate the work piece for uniform welding. Here, the wieldable end of the pipe (27) is positioned over a vee block (1) of the holding apparatus (23) whereas the wieldable end of the other pipe (28) rests on a job positioner present opposite to the vee block (1). The precise alignment of the pipes can be achieved by a job lifting wedge (5).
In the present inventive method, the cycle time has been reduced to 161 minutes from 678 minutes and the number of activities is reduced from 20 to 13 which makes the present proposed method more economical and energy efficient. Further, it ensures increased overall productivity with enhanced safety. The setting up of job is made simpler in comparison to existing methods. Also, the man-hours utilized for the fit-up is reduced from 13.5 hours to 3.25 hours.
The foregoing is considered as illustrative only of the principles of the present invention. Furthermore, since numerous modifications and changes will readily occur to those skilled in the art, it is not desired to limit the present invention to the operation shown and described. While the preferred embodiment has been described, the details may be changed without departing from the present invention, which is defined by the claims.

We claim:
1. A method of horizontally setting at least two separate weldable components
without using welding bridge plates over pluralities of surfaces of said at least two
separate weldable components, to achieve a reduction in cycle time and a
reduction in number of activities, the method comprising:
- mounting, removably on a holding apparatus (23), at least one weldable end of a first weldable component (24) based on physical parameters of the first weldable component;
- placing, flexibly on a roller support (29), at least one weldable end of a second weldable component (28) to accurately complete butt welding of two halves of weldable ends of the components in two stages by allowing smooth rolling of the second weldable component; and
- maintaining an exact root gap between the at least one weldable end of the first weldable component (24) and the at least one weldable end of the second weldable component (28);
wherein the setup is locked by the holding apparatus.
2. The method as claimed in claim 1, wherein the first weldable component may be irregular shaped or regular shaped and the second weldable component is regular shaped.
3. The method as claimed in claim 1, wherein the plurality of weldable ends comprise the at least one weldable end of the first weldable component and the at least one weldable end of the second weldable component.
4. The method as claimed in claim 1, wherein mounting the at least one weldable end of the first weldable component comprising:

- placing the at least one weldable end of the first weldable component on a top face plate (12) of the holding apparatus (23) by at least one of a plurality of first devices of the holding apparatus (23), wherein each of the plurality of first devices are provided along separate sides of the top face plate (12); and
- adjusting the at least one of the plurality of first devices with the help of a plurality of second devices of the holding apparatus (23) to accommodate

the weldable end of the first weldable component based on physical parameters.
5. The method as claimed in claim 4, wherein the plurality of first devices of the
holding apparatus (23) comprise:
- a vee block (1) provided along one side on the top face plate (12); and
- a plurality sets of job positioners (2) provided on the top face plate (12), wherein at least one set of job positioner is provided opposite to the vee block (1); and
- a job lifting wedge (5) provided on the top face plate (12) adjacent to the vee block (1).
6. The method as claimed in claim 4, wherein the plurality of second devices of the
holding apparatus (23) comprise:
- a plurality of pitch holes (3) provided adjacent to the bottom of the plurality sets of job positioners (2);
- a pair of job positioners holding bolt and nut (4) provided at the bottom of the plurality sets of job positioners (2);
- a screw rod (6) attached to a job lifting wedge (5);
- a first box nut (7) connected to the screw rod (6);
- a first handle (8) connected to the screw rod (6);
- a job height adjustment screw rod (10) attached to the vee block (1);
- a second box nut (9) connected to the job height adjustment screw rod (10); and
- a second handle (11) connected to the job height adjustment screw rod (10).
7. The method as claimed in claim 1, wherein maintaining exact root gap comprising:
- adjusting height of the first wieldable component by a plurality of third devices of the holding apparatus (23) such that vertical axes of the at least one weldable end of the first wieldable component and the at least one weldable end of the second wieldable component coincide; and
- aligning the at least one weldable end of the first wieldable component by controlling multi directional movement of the plurality of first devices by the plurality of second devices.

8. The method as claimed in claim 7, wherein the plurality of third devices of the
holding apparatus (23) comprise:
- a mechanical jack screw (14) connected to a plurality of top rib plates (13) provided at the bottom of the top face plate (12);
- a plurality of dowel pins (15) provided at inner sidewalls of the mechanical jack screw (14); and
- a lifting adjustment wheel (16) attached to the mechanical jack screw (14).
9. The method as claimed in claim 1, wherein the setup is locked by the holding
apparatus comprising the steps of:
- fastening a plurality of lock screws (22) to attach a movement locking unit
(21) to a bottom face plate (18) in the holding apparatus (23) for locking
the movement of the first weldable component and the holding apparatus
(23) assembly.
10. The method as claimed in claim 1, wherein the reduction in cycle time is at least 76 percentages.
11. The method as claimed in claim 1, wherein the reduction in number of activities is at least 35 percentages.
12. A holding apparatus (23) for implementing the method as claimed in claim 1, comprises:

- a top face plate (12) having at least one side devoid of structures to facilitate a rotation about vertical axis of the at least one weldable end of the first weldable component for welding of both halves;
- a vee block (1) and the plurality sets of job positioners (2) along sides on the top face plate (12), wherein one set of job positioner is placed opposite to the vee block (1) and another set of job positioner is placed adjacent to the vee block (1);
- a plurality of pitch holes (3) provided adjacent to the bottom of the plurality sets of job positioners (2) on the top face plate (12);
- a pair of job positioners holding bolt and nut (4) provided at the bottom of the plurality sets of job positioners (2) on the top face plate (12);
- a job lifting wedge (5) provided adjacent to the vee block (1) on the top face plate (12) for precise alignment;
- a screw rod (6) attached to a job lifting wedge (5);

- a first box nut (7) and the first handle (8) connected to the screw rod (6);
- a job height adjustment screw rod (10) attached to the vee block (1);
- a second box nut (9) and the second handle (11) connected to the job height adjustment screw rod (10);
- a plurality of top rib plates (13) provided at the bottom of the top face plate (12) for extra strength;
- a mechanical jack screw (14) connected to a plurality of top rib plates (13) for height adjustment of the first weldable component;
- a plurality of dowel pins (15) provided at inner sidewalls of the mechanical jack screw (14);
- a lifting adjustment wheel (16) attached to outer surface of the mechanical jack screw (14);
- a bottom face plate (18) attached to bottom end of the mechanical jack screw (14);
- a plurality of bottom rib plates (17) attached to the bottom face plate (18);
- a plurality of metallic wheels (19) at the corners of the bottom face plate (18);
- a pair of wheel mounting bolt and nuts (20) provided for attaching the plurality of metallic wheels (19) to the bottom face plate (18); and
- a movement locking unit (21) attached to the bottom face plate (18) by the lock screw (22).