International Journal of Science, Technology & Management
Volume No.04, Issue No. 03, March 2015
www.ijstm.com
ISSN (online): 2394-1537
WELDING ROTATOR WITH PROXIMITY SENSOR
Prof. P. D. Badgujar1, Prof. S. U. Gunjal2, Prof. P. R. Hatte3,
Raghuveer S. Chopade4, Varsha C. Bangar5
1,2
Asst. Prof., 3Asso. Prof. & Head of Dept., Department of Mechanical Engineering,
Sandip Foundation’s- SITRC, Mahiraavani, Trimbak Road, Nashik, Maharashtra, 422 213,
Savitribai Phule Pune University, Maharashtra,( India)
4,5
Department of Mechanical Engineering, Sandip Foundation’s- SITRC, Mahiraavani, Trimbak Road, Nashik,
Maharashtra, 422 213, Savitribai Phule Pune University, Maharashtra, (India)
ABSTRACT
Welding is the important joining process, having wide range of applications. There are various types of welding depends
on different criteria. Manual type of welding is mostly used in small to medium scale industrial applications. The real
challenge while doing welding manually is accuracy and safety of operator. While manual welding rotating job for
accurate welding is another important phenomenon associated, thus instrument is needed to rotate job/ workpiece.
Welding rotator does the required job accurately, this paper discuss the importance of welding rotator, its construction
and working in brief. Automation always leads to perfection, precision and accuracy. Use of sensor increases ease of
operation in process.
Keywords: Joining Process,Manual Welding, Rotating Job, Welding Rotator, Automation, Precision &
Accuracy
I INTRODUCTION
There are many manufacturing processes. There are several machining operations like casting, forging, surface finishing,
welding, milling, drilling etc plays an important role in any industry.
Welding is a fabrication or sculptural process that joins materials, usually metals or thermoplastics, by causing
coalescence. This is often done by melting the workpieces and adding a filler material to form a pool of molten material
(the weld pool) that cools to become a strong joint, with pressure sometimes used in conjunction with heat, or by itself, to
produce the weld [1]. This is in contrast with soldering and brazing, which involve melting a lower-melting-point material
between the workpieces to form a bond between them, without melting the workpieces.
Many different energy sources can be used for welding, including a gas flame, an electric arc, a laser, an electron beam,
friction, and ultrasound. While often an industrial process, welding can be done in many different environments, including
open air, under water and in outer space. Regardless of location, welding remains dangerous, and precautions are taken to
avoid burns, electric shock, eye damage, poisonous fumes, and overexposure to ultraviolet light.
65 | P a g e
International Journal of Science, Technology & Management
Volume No.04, Issue No. 03, March 2015
www.ijstm.com
ISSN (online): 2394-1537
In many cases periphery welding is needed to join two cylinders or two rectangular cubes and it is done by a person
carrying welding gun [2, 3]. But the deposition of material does not get equally over the periphery of workpieces.
There are many new technologies are to be introduce in last 10 years. Like friction stir welding, inertia friction welding,
by using welding fixtures or rotators. These are advanced automated technologies. It helps to give high quality of weld.
Which improves the performance of part welded and the look also.
1.1 Need of Welding Rotator with Proximity Sensor
In the present age of mass production it is often required to automate the manufacturing processes that were
conventionally done manually. The process of joining in many applications is welding. The welding may be of Electric arc
welding, CO2 Welding, or TIG welding. The process of Electric arc welding or CO 2 welding is normally done manually.
In electric arc welding after striking the arc the electrode is moved in the direction of welding maintaining an effective arc
gap, similar type of process is done in CO2 welding [4]. Moving the electrode along the welding line is a skill full work
and especially for circular components become much more difficult.
Manual operation though done by an expert works man will require the work piece to be rotated about a fixed axis for
good profile and homogeneous welding. Normally this process is done manually but the rate of rotation is not ensured,
hence the quality of weld is affected [5].
Hence the need of a special device which can rotate the job at a fixed rate to assist the welding process for circular
components and ensure good profile and homogeneous welding.
Fig.1 Welding To Cylindrical Disks.
Fig. 1 shows the circular welding to cylindrical plates. In this two discs are placed on each other and welding gun is move
along the joining axis of discs.
66 | P a g e
International Journal of Science, Technology & Management
Volume No.04, Issue No. 03, March 2015
www.ijstm.com
ISSN (online): 2394-1537
1.2. History
The history of joining metals goes back several millennia, with the earliest examples of welding from the Bronze Age and
the Iron Age in Europe and the Middle East. Welding was used in the construction of the iron pillar in Delhi, India, erected
about 310 AD and weighing 5.4 metric tons.
The middle Ages brought advances in forge welding, in which blacksmiths pounded heated metal repeatedly until bonding
occurred. In 1540, Vannoccio Biringuccio published De la pirotechnia, which includes descriptions of the forging
operation. Renaissance craftsmen were skilled in the process, and the industry continued to grow during the following
centuries.
In 1802, Russian scientist Vasily Petrov discovered the electric arc and subsequently proposed its possible practical
applications, including welding. In 1881–82 a Russian inventor Nikolai Benardos created the first electric arc welding
method known as carbon arc welding, using carbon electrodes. The advances in arc welding continued with the invention
of metal electrodes in the late 1800s by a Russian, Nikolai Slavyanov (1888), and an American, C. L. Coffin (1890).
Around 1900, A. P. Strohmenger released a coated metal electrode in Britain, which gave a more stable arc [6, 7]. In 1905
Russian scientist Vladimir Mitkevich proposed the usage of three-phase electric arc for welding. In 1919, alternating
current welding was invented by C. J. Holslag but did not become popular for another decade.
Resistance welding was also developed during the final decades of the 19th century, with the first patents going to Elihu
Thomson in 1885, which produced further advances over the next 15 years. Thermite welding was invented in 1893, and
around that time another process, oxyfuel welding, became well established. Acetylene was discovered in 1836 by
Edmund Davy, but its use was not practical in welding until about 1900, when a suitable blowtorch was developed. At
first, oxyfuel welding was one of the more popular welding methods due to its portability and relatively low cost. As the
20th century progressed, however, it fell out of favor for industrial applications. It was largely replaced with arc welding,
as metal coverings (known as flux) for the electrode that stabilize the arc and shield the base material from impurities
continued to be developed.
World War I caused a major surge in the use of welding processes, with the various military powers attempting to
determine which of the several new welding processes would be best [8]. The British primarily used arc welding, even
constructing a ship, the Fulagar, with an entirely welded hull. Arc welding was first applied to aircraft during the war as
well, as some German airplane fuselages were constructed using the process. Also noteworthy is the first welded road
bridge in the world, designed by Stefan Bryła of the Warsaw University of Technology in 1927, and built across the river
Słudwia Maurzyce near Łowicz, Poland in 1929.
During the 1920s, major advances were made in welding technology, including the introduction of automatic welding in
1920, in which electrode wire was fed continuously. Shielding gas became a subject receiving much attention, as scientists
attempted to protect welds from the effects of oxygen and nitrogen in the atmosphere [6, 8]. Porosity and brittleness were
the primary problems, and the solutions that developed included the use of hydrogen, argon, and helium as welding
atmospheres. During the following decade, further advances allowed for the welding of reactive metals like aluminum and
magnesium. This in conjunction with developments in automatic welding, alternating current, and fluxes fed a major
expansion of arc welding during the 1930s and then during World War-I.
67 | P a g e
International Journal of Science, Technology & Management
Volume No.04, Issue No. 03, March 2015
www.ijstm.com
ISSN (online): 2394-1537
II WELDING ROTATOR WITH PROXIMITY SENSOR
2.1 Introduction
On industrial shop floor, many times circular welding is done manually. That is a person move welding gun around the
periphery of the workpiece. But poor quality of weld is obtained because it is very difficult to move a welding gun around
the workpiece with constant speed and to maintain the distance between gun and workpiece [7, 8]. It causes the wastage of
man-hours and raw material.
Fig. 2 Welding Rotator
Fig. 2 shows, the welding rotator and its different elements. Welding rotator it is device which may be use for qualitative
circular welding. Welding rotators are probably useful and versatile of positioning equipment for a fabrication shop. While
using rotator, the welding gun is fixed and the workpiece rotate. The workpiece is rotate with help of electric motor and
worm and worm wheel arrangement. The belt and pulley is use to transmit power from motor to worm and worm wheel.
2.2 Problem Definition
In an organization manufacturing concern there is shortage of skill operator for circular welding purpose. That directly
affects the quality of product and production rate. Due to absence of skill operator, the total production cycle disturb for
whole day. If the unskilled operator is employed for the same work this result in poor quality of weld and wastage of raw
material. It is necessary to pay more salary for skill operator as compare to other operator.
Most of all unskilled operator faces following problems while doing circular welding:1. He/she consume more time than skill operator.
2. The production rate decreases.
3. Affected quality of product because the indexing of weld is not proper.
4. The poor run of weld while welding.
68 | P a g e
International Journal of Science, Technology & Management
Volume No.04, Issue No. 03, March 2015
www.ijstm.com
ISSN (online): 2394-1537
Fig. 3 Manual Welding
Fig. 3 shows the man doing welding with the help of welding gun.
III CONSTRUCTION AND WORKING
3.1. Construction
Welding rotator with proximity sensor consists of two circular metallic plates one of; base plate and is working plate
having a diameter of 260 mm & 228 mm respectively. It also consist of gear having 100 mm diameter, pulley, Inching
switch, Electronic Proximity sensor, Electronic relay, Electronic Speed Regulator, Indexer buttons, Ball bearing ,Bearing
housing, Table shaft, Table, Worm Wheel Shaft, Motor, Belt Drive, Worm Wheel.
The shaft is mounted on a working plate. The gear portion below the shaft is connected to the worm shaft. Another end of
worm shaft is connected to belt and pulley arrangement which is driven by means of stepper motor. Shaft has been
inserted along with circular bearing to prevent the relative motion [9, 10]. The motor is controlled by means of a control
panel. It consists of a relay, for controlling the speed of motor, a switch to on and off the power supply. Proximity sensor
is used to stops the motor or working plate after one complete rotation of the working plate. A metallic strip is attached to
the working plate, so that when it reaches in front of proximity sensor, then the electric supply stops. Proximity sensor
controls the electronic relay. The welding rotator with proximity sensor consists of the following parts;
3.1.1 Motor
Motor is a Single phase AC motor, speed is continuously variable from 0 to 6000 rpm. The speed of motor is variated by
means of an electronic speed variator. The power input to motor is varied by changing the current supply to these brushes
by the electronic speed variator; thereby the speed is also is changes.
69 | P a g e
International Journal of Science, Technology & Management
Volume No.04, Issue No. 03, March 2015
www.ijstm.com
ISSN (online): 2394-1537
Fig 4 Construction of Welding Rotator
Fig 4 shows the construction of welding rotator with proximity sensor.
70 | P a g e
International Journal of Science, Technology & Management
Volume No.04, Issue No. 03, March 2015
www.ijstm.com
ISSN (online): 2394-1537
3.1.2 Belt Drive
The power from the motor is supplied to the input shaft of the mechanism by means of an open belt drive. The drive
comprises of the motor pulley mounted on the motor shaft, the belt FZ 6x 500, and reduction pulley mounted on the input
shaft.
3.1. 3 Reduction gear box
Reduction gear box is a worm and worm wheel gear box with ratio of 1:80 ratios. The gear box comprises of the
following parts:
a )Input Worm Shaft
The input shaft is a high grade alloy steel (20MnCr5) part held in ball bearings at either end carries the reduction pulley at
one end. Input worm shaft has the following specifications:
Gear Data
Addendum diameter (Da1) = Φ 27 mm
Dedendum diameter (Df1) = Φ 20.4 mm
No. of starts = 1
Hand of operation = Right hand
Module = 1.5mm
b) Worm Wheel
The worm wheel is cast iron part keyed to the worm wheel shaft. Worm Wheel has the following specifications:
Addendum diameter (Da2) = Φ 123mm
Dedendum diameter (Df1) = Φ 116.4 mm
No. of teeth = 80
Hand of operation = Right hand
Module = 1.5mm
Bore diameter = Φ 22 mm
Keyway = 6x3x30
c) Worm Wheel Shaft
Fig 5 Worm Wheel
71 | P a g e
International Journal of Science, Technology & Management
Volume No.04, Issue No. 03, March 2015
www.ijstm.com
ISSN (online): 2394-1537
The worm wheel shaft is a high grade alloy steel (EN24), held in ball bearings at either ends and carries the muff coupling
to upper end. The worm wheel is keyed to the worm wheel shaft.
Fig 5 shows the worm wheel. The worm wheel is rotated with the help of worm shaft. Generally it is use to convert linear
motion to rotary motion.
3.1.4 Table
The upper circular plate is also known as working table. The table is made from structural grade steel (EN9). The shaft is
welded to the table. The table holds the work piece on its top end. The table is provided with tapped holes that clamp the
indexer buttons with the help of studs.
3.1.5 Table shaft
The table shaft is a high grade alloy steel (EN24), held in ball bearings at one ends and carries the muff coupling to lower
end. The table is welded to the table shaft making an integral part.
3.1.6 Ball bearing
Fig. 6 Ball Bearing
Fig. 6 shows the single row ball bearing. The single row ball bearing has internal diameter 25 mm, outside diameter 52
mm and width 15 mm. It is provided with metallic dust covers or seals at both ends. It supports the table shaft in the
bearing housing.
3.1.7 Bearing housing
The casing plates are of structural grade steel (EN9). It holds the ball bearing to support the table shaft. It is welded to the
indexer table base frame and is provided with holes that receive the worm gear box support pins.
3.1.8 Frame
Frame is a mild steel (MS) structure made from square tube 20x20x2mm. It supports the entire assembly of the indexer
table. It provided with a sheet metal panel which holds the sensor, relay, and speed regulator and inching switch.
72 | P a g e
International Journal of Science, Technology & Management
Volume No.04, Issue No. 03, March 2015
www.ijstm.com
ISSN (online): 2394-1537
3.1.9 Electronic Speed Regulator
Electronic speed regulator is device use to control the speed of equipment. The power input to motor is varied by
changing the current supply to these brushes by the electronic speed variator; thereby the speed is also is changes.
3.1.10 Electronic relay
Fig. 7 Electronic relay
A relay is an electrically operated switch. Many relays use an electromagnet to operate a switching mechanism
mechanically. The electronic relay is mounted on the sheet metal panel on the base frame. The electronic relay is
connected to the proximity sensor and the motor input circuit. The function of the electronic relay is to cut off power
supply when the proximity sensor is operated.
3.1.11 Electronic Proximity sensor
Fig. 8 shows the electronic proximity sensor. It is mounted on the sheet metal panel on the base frame by means of a Z
shaped clamp. The proximity sensor as the name suggests senses the proximity of the indexer buttons which acts as stops,
such that when they come in front of the proximity sensor the table the relay is operated to stop the table motion. The
proximity sensor is connected to the electronic relay and the power source.
Fig. 8 Proximity Sensor
73 | P a g e
International Journal of Science, Technology & Management
Volume No.04, Issue No. 03, March 2015
www.ijstm.com
ISSN (online): 2394-1537
3.1.12 Inching switch
It is an electrically controlled switch used for switching a power circuit. The inching switch is connected between the
electronic relay and the proximity sensor, this switch when operated by-passes the proximity sensor, thereby operating the
motor momentarily as long it is kept pressed.
3.2 Working
The workpiece to be welded is placed on the indexer table and considering the welding process and electrode size the
speed regulator is adjusted to give desired table speed. The table carries indexer buttons as per number of welds and
position of the same [11]. Table is indexed to the first stop position. Now inching switch is operated simultaneously as the
welding process is started. The job rotates as welding operation is done. When the second indexer button comes in front of
the proximity switch it stops the welding process and the table movement. Inching switch is operated which starts the next
position welding and the process is repeated till the last stop i.e. the first stop comes in front of the proximity switch. The
job welded is unloaded and new work-piece is loaded for the next operation.
Fig 10 shows the working of welding rotator. The steel bar is to be weld, with the help of welding rotator, to a circular
ring.
Fig 9 Working of Welding Rotator
IV FUTURE SCOPE
In future the whole system can be control with the help of remote control so that the human effort will be reduce. It may
be computerize control with the help of software. The specifications may be extending as per need of users or depending
upon production rate. The motor can attach directly to the worm wheel shaft which will reduce the energy loss as well as
reduces the constructional complications. Welding gun holder can attach to the base plate with help of welding fixture.
V CONCLUSION
From the above report, it is concluded that, welding rotator is very essential equipment for heavy and light fabrication
shop. It is mainly used to rotate or position the cylindrical jobs for circumferential welding. A substantial opportunity
74 | P a g e
International Journal of Science, Technology & Management
Volume No.04, Issue No. 03, March 2015
www.ijstm.com
ISSN (online): 2394-1537
exists in the technology of using welding rotator to relieve people from boring, repetitive, hazardous and unpleasant work
in all forms of a human labour.
On the shop floor level, an organization pays Rs.6000 per month for a skilled operator. While the initial investment in the
welding rotator is nearly Rs.11000/-. The production rate for manual welding is 150 jobs per day; hence the manual
welding is very time consuming. While using welding rotator the production rate is increased up to 225 jobs per day (By
considering 8 Hr). An investment of welding rotator is covered within 3 months. Simultaneously, the man-hours and
human effort require is reduced. The wastage of weld material decreased compare to the manual welding.
REFERENCES
[1] http://www.twi.co.uk/content/ weldingintro.html
[2] http://ntrs.nasa.gov/archive/nasa/casi.ntrs.nasa.gov/20080009619_2008009118.pdf
[3] R.V. Patil, “Design Of Machine Elements”, Techmax Publications, Edition 2008, P.P. 6.1-6.19
[4] S.Chand, “Machine Design”, Nirali Publications, Aug 2005, P.P. 2.1-2.24
[5] Bhandari, Design Of Machine Elements, Tata McGraw Hill Publications, P.P.8.1-8.14
[6]http://www.scribd.com/doc/111206163/Welding-Fixture-With-Active-Position-Adapting-Functions
[7] http://www.robots4welding.com/articles.php?tag=674
[8] American Welding Society (2004). Welding Handbook, Welding Processes, Part 1. Miami: American Welding Society.
ISBN 0-87171-729-8.
[9] J. S. Katre, “Electrical Technology”, Vrinda publications, P.P. 5.1-5.7
[10] R. B. Patil, “Machine Design”, Tech-max publication, P. P. 8.1-8.10.
[11] M. S. Mahajan, “Production engineering”, Vrinda publication, Aug 2005, P. P. 3.31-10.27.
75 | P a g e