Description:“SEMI-AUTOMATIC MIG WELDING MACHINE FOR LONGITUDINAL STRUCTURAL FABRICATIONS”

FIELD OF INVENTION:

[001] The present invention involves substitution of MIG manual welding process by Semiautomatic welding in manufacturing. Particularly the present invention relates to design and fabrication of the Semi-automatic MIG welding machine movement mechanism for longitudinal structural fabrications, such as I beam, column box, tube with fins welding etc.

BACKGROUND OF 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] The Applicant is manufacturing boiler pressure parts such us Drum, Various coils, Panels, Headers, Valves, I beam etc. Recently, it started manufacturing of non-pressure parts assemblies also. Due to product change from pressure parts to non-pressure parts (structural beam, columns) in some bays, automation of Manual welding machines is planned to be taken up for non-pressure parts jobs to meet higher output requirements.
[004] Boiler Structural components fabrications required more volume of welding (more length and bigger fillet size) and will be time taking to complete voluminous welding of Structural components welding.

[005] Due to involvement of manual welding, average manual welding duration of 10 mte long I beam is taking 105.6 hrs. On an average around 1050 electrodes of 05 mm diameter is required to weld a 10 m length beam, which leads to less productivity.

[006] Due to uneven heating during manual welding process because of higher heat input, one side of the I Beam is heated for longer duration and bends are being observed in the beam.

[007] The manual welding process like SMAW is prone to various welding defects such as Incomplete fusion, Lack of fusion, Slag inclusion, Incomplete penetration, Spatter.

[008] Welders work in a hazardous atmosphere continuously in manual welding process.

[009] Manual welding process to weld the structural component is time consuming. Hence, there is a need to find out an alternate method of increasing the productivity and cycle time reduction in welding of structural beam.

OBJECTS OF INVENTION
[0010] Primary object of the present invention is to provide Semi-automatic MIG welding machine for longitudinal structural fabrications
[0011] Another object of the invention is to reduce the man power involvement because of manual welding process.
[0012] Still another object of the invention is to increase productivity by conversion to the semi-automated machine mechanism for MIG torch movement.

[0013] Yet another object of the invention is to reduce welding rework, which was found during manual welding process.

[0014] One another object of the invention is to provide safety working atmosphere to machine operator using smoke recovery system.

[0015] A still another object of the invention is one important aspect towards HSE policy [Health Safety Security and Environment Policies].

[0016] 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 INVENTION
[0017] 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.

[0018] The present invention involves a mechanism for MIG torches assembly movement using H – beam for welding of structural items comprising: --
- Torch assembly (Figure I, 12) - The locknut based slotted plate mechanism for torch movement along transverse and vertical direction to the job.

- Rack (Figure I, 04) and Pinion (Figure I, 05) are mounted with H- Beam for longitudinal movement of torch unit for the welding of job

- Guide rail (Figure I, 02) with machine bed (Figure I, 01) assembly for uniform movement of welding unit during welding.

- Variable frequency Drive (Figure I, 06) based movement of welding unit for variable speed of welding unit / torch as per required welding parameter.

[0019] According to the invention, there is provided Semi-automatic MIG welding machine for longitudinal structural fabrications comprises of:

[0020] Machine base [1], at the top and one side of which guide rail (02) and Rack assembly (04) is fixed respectively, pinion (05) is fixed with geared motor (07), MIG welding power source (09) is mounted on the trolley (08), in which Assembly of movement trolley (08) is fixed on the machine bed [01] and geared motor (07) with pinion (05) unit is mounted on the trolley (08);

[0021] Variable frequency drive (VFD) (06) panel is installed near to operator on moving trolley (08) for operating the welding unit movement.

[0022] The inventive features of invention have been indicated in the principal claim and subsidiary features have been discussed in the dependent claims.

[0023] 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.

[0024] 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.

[0025] 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
[0026] The illustrated embodiments of the subject matter will be best understood by reference to the drawings, wherein like parts are designated by like numerals throughout. The following description is intended only by way of example, and simply illustrates certain selected embodiments of devices, systems, and processes that are consistent with the subject matter as claimed herein, wherein:-

[0027] Figure 1 shows: Schematic arrangement of Semi-automatic MIG welding machine for longitudinal structural fabrications and welding unit movement mechanism according to the present invention.

[0028] Figure 2 shows: Different components of the Semi-automatic MIG welding machine of the present invention.

[0029] 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.

DETAIL DESCRIPTION OF PREFERRED EMBODIMENT OF INVENTION WITH REFERENCE TO THE ACCOMPANYING DRAWINGS
[0030] 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.

[0031] The invention has been devised to automate the welding of boiler structural components by Metal Inert Gas (MIG) process.
With the aim to improve productivity, design and fabrication was done of the Semi-automatic MIG welding machine movement mechanism for structural beam fabrication.

[0032] Now, reference may be made to figure 1 for Semi-automatic MIG welding machine of invention, which comprises the following components:

• Machine base [01] – it is substantially “H” Beam used as base of machine, which is an important feature as quality of weld depends on machine base.

• Guide rail [02] and roller [03] – Solid bar is used as guide rail (02) and flat roller (03) is made by lathe operations, which is useful for welding head straight movement.

• Rack & Pinion [04 & 05] – The Rack (04) and Pinion (05) assembly is used to convert rotational motion into linear motion. By using this application, welding torch head and welding power source (09) move from one end to other end. Rack (04) assembly is mounted on machine base and Pinion (05) is fixed with geared motor (07).

• Geared motor [07] – The geared motor (07) is having the ability to deliver high torque at low speeds. Said pinion (05) is fixed with geared motor (07) output shaft.

• Moving trolley [08] – Fabricated trolley (08) arrangement is used for fixing of geared motor (07) and keeping an MIG welding power source (09).

• A variable frequency drive (06) i.e. VFD—It is a type of motor controller that drives the electric motor by varying the frequency and voltage of its power supply. Geared motor (07) rpm is controlled by the variable frequency drive (06).

• MIG Welding unit (09)– The manual MIG welding power source (09) is used for welding application, which is mounted on moving trolley (08)

• Welding torch [12] – MIG Welding torch is used for higher weld deposition. Adjustment of torch is done by using slotted type mechanism (12).

• Blower [10] – A blower (10) is provided to create negative pressure with respect to the atmospheric pressure at the entry of flexible hose (11) to suck the fumes coming out during welding operation.

• Flexible Hose – It provides connection between fumes collecting header and blower (10), similarly blower to chimney.

• Cable track chain [13] – A flexible hollow structure is used to guide, support and protect power cable during linear movement of Welding machine assembly. Cable track chain (13) is connected to moving trolley (08) on one end and connected with machine base (01) starting point on other end (13).

• Chimney (based on draft so that fumes will come out through chimney without back flow)- Fumes go out through chimney (approx. height 30 feet) to the atmosphere.

[0033] The following activities / works were planned and executed for creating this exclusive facility:
i. The total length of the job is for example up to 20 mtr. Therefore, the length of machine bed fixed for example up to 20m length. “H” Beam (01) is planned to be utilized as machine bed.

ii. The Rack assembly (04) is attached with "L" Angle using bolts and nuts, and then welded to one side of the Machine bed (01).

iii. The Solid guide rail (02) is welded at top side of machine bed (01) after checking the measurements for movement of welding Machine.

iv. Boring and keyway making operations are performed in Pinion (05) as per geared motor (07) shaft dimensions, thereafter pinion (05) is fixed with geared motor (07).

v. The fabrication of movement trolley (08) is completed. After that Guide roller and supporting rollers are fixed. Similarly, MIG welding power source (09) is mounted on the trolley (08).

vi. Assembly of movement trolley (08) fixed on the machine bed [01]. Then geared motor (07) with pinion (05) unit is fixed on movement trolley (08). Rack (04) and pinion (05) is suited by adjusting the geared motor (07) slotted hole. MIG welding torch is placed on trolley. Variable frequency drive (VFD) (06) panel is fixed near to operator on moving trolley for operating the welding unit movement. The speed of Welding unit and welding torch speed can be varied according to job heat input requirement because heat input also depends upon the travel speed of the welding torch i.e. travelling speed of Welding unit.

vii. The locknut based slotted plate mechanism fabricated (12) for the movement of welding torch transverse to the job up to for example 1.5mtr, similarly same mechanism is used for vertical torch movement up to for example 2mtr height to accommodate various sizes of jobs.

viii. Fume extraction unit is installed near to welding area. The flexible hose (11) at one end is connected to the Blower (10) and other end is placed on welding area. Blower creates negative pressure at the welding area point therefore fume is collected through the flexible hose (11).
ADVANTAGES OF THE INVENTION
[0034] After introduction of Semi-automatic MIG welding machine mechanism, the manual welding process was totally eliminated. The welding duration by using semi- automated rack and pinion based mechanism for Structural items has reduced significantly and taking approximately 20% time of manual welding process.

[0035] This invention leads to increase in productivity, reduction in defects, Elimination of distortion, safe working condition.

WORKING OF THE INVENTION
In this Invention, I- Beam, Box type job etc structural components can be welded. This machine is primarily suitable for Longitudinal welding of job.
First of all, job shall be placed on fixture parallel to welding machine torch travel axis.
According to the job requirements, semi-automatic MIG welding torch position will be adjusted by using of slotted torch holding mechanism.
After torch positioning, geared motor based torch assembly trolley fixed with pinion will move on rack and pinion mechanism parallel to job.
The speed of torch assembly trolley can be varied according to the welding speed requirement of job. It means, it will be as per WPS heat input requirements of job.
The movement is controlled by Variable frequency drive (VFD).
Welding smokes are coming out during welding is sucked by installed fume extraction unit.

TEST RESULT
Man days Performance comparison
Man-days availed for welding of the 10 m length beams (15 mm welding bead) by manual welding are as follows:
Total man-days taken for welding operation of the I beam = 121.6/8 = 15.1 man-days/beam
Welding duration by using semi- automated mechanism for Structural I beam component size of 10 meter as per below details:
Total man-days taken for welding operation of the I beam = 24/8 = 03 man-days/beam
Therefore, 12 man-days saving per I Beam of length 10 meter (welding length 40 meter, fillet size 15 mm) in an exemplary embodiment.
REFERENCE NUMERALS
- Machine base-1
- Guide rail base-2
- Roller base-3
- Rack base-4
- Pinion base-5
- Geared motor base-7
- Trolley base-8
- VED base-6
- Slotted mechanism welding torch unit base-12
- MIG Power source base-9
- Blower base-10
- Flexible hose base-11
- Cable track chain base-13
[0036] 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.

[0037] 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.

[0038] 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”.

[0039] 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.

[0040] 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.

[0041] 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.

[0042] While various aspects and embodiments have been disclosed herein, other aspects and embodiments will be apparent to those skilled in the art. The various aspects and embodiments disclosed herein are for purposes of illustration and are not intended to be limiting, with the true scope and spirit being indicated by the following claims.
, Claims:We Claim
1. Semi-automatic MIG welding machine for longitudinal structural fabrications comprises of:
Machine base [1], at the top and one side of which guide rail (02) and Rack assembly (04) is fixed respectively, pinion (05) is fixed with geared motor (07), MIG welding power source (09) is mounted on the trolley (08), in which Assembly of movement trolley (08) is fixed on the machine bed [01] and geared motor (07) with pinion (05) unit is mounted on the trolley (08);

Variable frequency drive (VFD) (06) panel is installed near to operator on moving trolley (08) for operating the welding unit movement.

2. The Semi-automatic MIG welding machine as claimed in claim 1, wherein the Rack (04) and pinion (05) are suited by adjusting the geared motor (07) slotted hole, in which the MIG welding torch is placed on the trolley (08).

3. The Semi-automatic MIG welding machine as claimed in claim 1 or 2, wherein the speed of Welding unit and welding torch speed is varied according to job heat input requirement.

4. The Semi-automatic MIG welding machine as claimed in claims 1-3, wherein the locknut based slotted plate mechanism (12) is provided for the movement of welding torch transverse to the job and the mechanism is used for vertical torch movement so as to accommodate various sizes of jobs.

5. The Semi-automatic MIG welding machine as claimed in claims 1-4, wherein fume extraction unit is installed near to welding area.

6. The Semi-automatic MIG welding machine as claimed in claims 1-5, wherein the flexible hose (11) at one end is connected to the Blower (10) and other end is placed on the welding area.

7. The Semi-automatic MIG welding machine as claimed in claims 1-6, wherein the Rack assembly (04) is attached with "L" Angle using fasteners.
8. The Semi-automatic MIG welding machine as claimed in claims 1-7, wherein said rack (04) assembly is mounted on machine base and the Pinion (05) is fixed with said geared motor (07).
9. The Semi-automatic MIG welding machine as claimed in claims 1-8, wherein a blower (10) is provided to create negative pressure with respect to the atmospheric pressure at the entry of flexible hose (11) to suck the fumes coming out during welding operation.
10. The Semi-automatic MIG welding machine as claimed in claims 1-9, wherein Cable track chain (13) is connected to the moving trolley (08) at one end and connected with the machine base (01) starting point at other end.