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Quarterly Publication Rs. 20
January 2019 Weld 17 Bead 4
IWS 2k18
AROUND IWS
IWS AWARDS 2018
GET-TOGETHER MEETING WITH
OTHER PROFESSIONAL BODIES
KNOWLEDGE SHARING
SHORT TERM CERTIFICATE COURSE IN
WELDING TECHNOLOGY (Level-1) FOR
PRACTICING WELDERS AT NORTH EAST
INDIA
INTERNATIONAL WELDING SYMPOSIUM
2018 (IWS 2K18) AT MUMBAI
WORKSHOPS AND SEMINARS
COURSES BY SZ
TECHNICAL PAPERS
DEMAGNETISATION OF TUBE ENDS IN
COIL AND PANEL WELDING SHOP – OUR
EXPERIENCE
USE OF TIP-TIG TECHNOLOGY IN
PROCESS EQUIPMENT PLANTS
THE JOURNAL OF
Regn. No. 41817 / 2002
QUARTERLY PUBLICATION
Jan 2019 Weld: 17 Bead: 4
PRESIDENT
SHRI S BISWAS
Immediate Past President
SHRI S GOPINATH
Past President
SHRI A V KRISHNAN
Vice Presidents
SHRI A MARUTHAMUTHU SHRI U D RANE SHRI M P JAIN
Hon. Secretary
SHRI N RAJASEKARAN
Hon. Treasurer
SHRI G RAJENDRAN
Members
Dr K Asokkumar Shri R Subburayalu
Mrs. A Santhakumari Dr. T Senthil Kumar
Shri S Rajendran Dr. K Siva Prasad
Dr G Madhusudan Reddy Dr Shashikantha Karinka
Shri Narain Dharmendra Dr V R Krishnan
Prof. Sunil Pandey Dr G Padmanabham
Shri Basu B K Shri Muneesh Narain
Shri Umesh Agarwal Dr T A Daniel Sagaya Raj
Shri Sandeep Mohan Ubhaykar Shri Uma Shanker G
Shri Amit Agarwal Dr T J Prasadarao
Shri Viral Ashok Shah Shri S N Roy
Shri Easwaran R Prof. V Balasubramanian
Shri Tamboli V B Dr M Kamaraj
EDITORIAL BOARD
Shri R SUBBARAYALU – Editor in Charge Dr. G Madhusudhan Reddy Dr. V. Balasubramanian Mrs. A. Santhakumari Dr. T. Senthilkumar
ASSOCIATE EDITORS Shri Praveen Kumar Lakavat Shri R. Arivalagan
CO-ORDINATORS Shri Sanjay Kadam Shri K Ganesh Kumar Dr. S. Aravindhan
PUBLISHED BY
On Behalf of IWS by
Shri N RAJASEKARAN Hon. Secretary (IWS)
INDIAN WELDING SOCIETY INSTITUTIONS BUILDING, KAILASAPURAM, TIRUCHIRAPPALLI – 620 014
INDIA Websites: www.iws.org.in www.iwsevents.com E mail: hiwsindia@gmail.com
Page 3 of 25
IWS JOURNAL
Sincerely Thanks
IWS JOURNAL
CONGRATULATES
Dr. V R KRISHNAN
THE RECIPIENT OF
M ISMAIL MEMORIAL LIFE TIME ACHIEVEMENT
AWARD 2017
M ISMAIL MEMORIAL LIFE TIME ACHIEVEMENT AWARD 2017
Page 5 of 25
IWS JOURNAL
CONGRATULATES
Mr. V K SHIRGAOKAR
THE RECIPIENT OF
IWS FOUNDER PRESIDENT LIFE TIME ACHIEVEMENT
AWARD 2018
IWS FOUNDER PRESIDENT LIFE TIME ACHIEVEMENT AWARD 2018
IWS JOURNAL
CONGRATULATES
Mr S GOPINATH
THE RECIPIENT OF
IWS MERITORIUS AWARD 2017
IWS MERITORIOUS AWARD 2017
Page 7 of 25
IWS JOURNAL
CONGRATULATES
Mr R EASWARAN
THE RECIPIENT OF
IWS MERITORIUS AWARD 2018
IWS MERITORIOUS AWARD 2018
IWS JOURNAL
CONGRATULATES
Mr RAJESH KUMAR GUPTA
Mr PRATAP K SUPALI & Dr K MOHAN
RECIPIENTS OF
IWS ZONAL MERITORIOUS AWARD 2018
IWS Zonal Meritorious Award 2018
Page 9 of 25
IWS JOURNAL
CONGRATULATES
Mr A V KRISHNAN
Mr V B TAMBOLI
Dr K ASOKKUMAR
Mr G RAJENDRAN
Mr S SINGARAVELU
&
Mr MUNEESH NARAIN
IWS HONORARY FELLOW MEMBERSHIP 2018
RECIPIENTS OF
IWS
HONORARY
FELLOW MEMBERSHIP
2018
GET-TOGETHER MEETING WITH OTHER PROFESSIONAL
BODIES
On October 18, 2019, on the day of
Ayudha Pooja Celebrations, a get-together
meeting with other professional bodies,
viz. IIM, IIW and CSI was conducted at the
Institutional Building, Kailasapuram Township,
Tiruchy by the Southern zone.
Chairman (IWS, SZ) & Chairmen of other professional bodies and host
of senior members from all professional bodies graced the event.
@ CENTRES AND ZONES
IWS AT NORTH EASTERN PART OF THE COUNTRY AGAIN
SHORT TERM CERTIFICATE COURSE IN WELDING TECHNOLOGY (Level-1) FOR
PRACTICING WELDERS AT NORTH EAST INDIA
Continuing its focus on empowering the youths in the north
eastern part of the country, the Northern Zone of the society
through the Guwahati Centre conducted a short term
certificate course in welding technology from October 3, 2018
to October 14, 2018. The event was conducted at IIT,
Guwahati. 18 participants attended the course and got
benefitted. Theoretical input was given in the afternoon
sessions and practicals were conducted in the morning
sessions. On 13th Oct 2018, the students undergone the theory examination and practical examination
on 14th October 2018. Mr. M P Jain, Vice President addressed the participants during the valediction
and distributed the certificates to the qualified welders.
AROUND
Page 11 of 25
INTERNATIONAL WELDING SYMPOSIUM
2018 (IWS 2K18) AT MUMBAI
The International Welding Symposium 2018 (IWS
2K18) was successfully conducted at Mumbai during
27- 29 November 2018 in association with the
Welding Research Institute (WRI), Messe Dusseldorf
India, Messe Essen, DVS and Asian Welding
Federation. Shri Atul Sobti, Chairman & Managing
Director of BHEL Tiruchirappalli, inaugurated the
symposium. Shri Subrata Biswas, President (IWS)
and Director (E, R & D), BHEL presided over the
function. Mr. P K Supali, Vice Chairman, IWS, WZ, welcomed the gathering. Mr. Thomas Schlitt,
Managing Director, Messe Dusseldorf India and Mr. Torben Brinkmann, Head (IEM), Messe Essen
GmbH, Germany offered their felicitations. Mr A
Maruthamuthu, Vice President (IWS) briefed about IWS 2k18.
Mr. N Rajasekaran, Hon. Secretary (IWS) conducted the
proceedings and proposed vote of thanks. Mr. Atul Sobti
released the proceedings and Mr M P Jain, Vice President
received the first copy of the proceedings.
Few of the highlights about IWS 2k18 are as follows.
It is the 8th in the sequel and 5th consecutive event at Mumbai by IWS, WRI, MDI, ME, DVS and
AWF.
Dr. V R Krishnan has been conferred with the M. ISMAIL MEMORIAL LIFE TIME ACHIEVEMENT
AWARD 2017.
Mr. V K Shirgaokar conferred with the FOUNDER PRESIDENT LIFE TIME ACHIEVEMENT AWARD
2018.
Mr. S Gopinath former President (IWS) & former ED, BHEL,
Tiruchy and Mr R Easwaran, former Chairman (Technical
Committee) were awarded with the IWS MERITORIOUS
SERVICES AWARD 2018 & 2017 respectively.
Dr. S Rajakumar of CEMAJOR and Mr. Manish Tak of ARCI
received the Young Technologist Awards for institute and
industry categories respectively.
Mr A V Krishnan, Former President, Mr G Rajendran Hon. Treasurer, Mr Muneesh Narain & Mr V
B Tamboli former vice presidents, Dr. K. Asokkumar, Former Secretary and Mr. S. Singaravelu Vice
Chairman, IWS, SZ were conferred as Fellow Members of IWS.
In total 93 papers were received and 85 were presented including 8 overseas papers.
Participation was from 82 organisations and senior consultants. The participants from major
corporate companies in strategic sectors included BHEL, NTPC, DRDO, EIL, BEML, ISRO, HPCL,
Indian Railways, L&T, ADOR, D&H, etc. in the 2018 edition
252 delegates registered for the event from all categories and 226 attended the event. Free
Delegates from IWS Student forum were allowed to
attend the three-day event.
Mr. D S Honavar delivered the valediction address and
distributed the Young technologist awards and best
paper awards. Mrs. A. Santhakumari, AGM (WRI) &
NGC Member summed up the proceedings. Mr V K
Shirgaokar, former vice president (IWS) presided over
the function. Mr Sanjay Kadam, Hon. Secretary, WZ
welcomed the gathering. Mr G Rajendran, Hon. Treasurer proposed the vote of thanks. Mr. N
Rajasekaran, Hon. Secretary conducted the proceedings.
Page 13 of 25
Page 15 of 25
DEMAGNETISATION OF TUBE ENDS IN COIL AND PANEL WELDING
SHOP – OUR EXPERIENCE
N. Dhanasekaran, N. Rajasekaran* & A. Santhakumari*
ASNT NDT LIII (PT, MT, RT, UT), Consultant & Faculty
* BHEL, Tiruchirappalli, India
ABSTRACT
Qualitative and reliable welding connections are of increasingly greater importance.
Components requiring time-consuming edge and welding preparation and precise welding
sequences, the stated quality is more difficult than ever to achieve. Adding component
magnetism to this quickly makes flawless welding quality, a challenge for every welder to attain.
Magnetism in a component causes the arc to deflect, meaning that it can no longer burn stably
and defect free sidewall fusion can no longer be ensured. With GMAW processes, it also leads to
uneven droplet detachment, which can manifest as spatter on the component or interrupt the
arc in case of strong magnetism. Inadequate welding results and time-consuming finishing work
are the result, and this can be costly. Using the fundamentals of magnetism, ferromagnetic
materials and the consequences of magnetism while welding as a starting point,
demagnetization options which were adopted to solve recent problems during tube to tube butt
weld preparation are presented here. In addition to theoretical considerations, day-to-day use
and application tips for production personnel are primary focus which enable reliable welding.
1.0 INTRODUCTION
Magnetism and magnetic phenomena have been known for a long time. While magnetism was
observable only in magnetic iron ore, one can see it in many natural phenomena and technical
applications today. In terms of Physics, the strength of a magnetic field can be defined by the
magnetic field strength H and the magnetic flux density B (magnetic induction). The higher the
field strength H, higher the flux density B. When H becomes zero, a residual flux density remains.
Residual magnetism is the reason for arc instability during welding, the arc weaves and is
deflected, drops do not evenly detach, sidewall fusion is improper and the welding result is of
poor quality.
2.0 FERROMAGNETIC MATERIALS
Ferromagnetic material is magnetic without the influence of an external field. The reason for this
can be looked at in different ways. While, at the atomic level, electron shells interact via orbital
and spin angular momenta to create a parallel alignment of the atomic magnetic moments
causing magnetisation. Physicist Weiss came up with the idea of interpreting the phenomenon
due to the existence of magnetic domains. Each Weiss domain has all magnetic moments within
it aligned in the same direction and has a neighbour of identical size which points in the opposite
direction. Magnetic fields in semi-finished products made of ferromagnetic materials neutralize
each other in the semi-finished product after production and cooling, as the Weiss domains are
in equilibrium. When producing metal pipe and tube cuttings from a continuously cast semi-
Page 17 of 25
finished product, the Weiss domains are separated from each other and are no longer in
equilibrium. These imbalances influence the arc during welding and it may occur at edge prepared
sidewalls to be welded joint. Magnetic particle testing carried out especially at the edge
preparation ends of pipes and tubes using direct current / half wave DC may also cause
magnetism in the pipe and tube sections.
Ferromagnetic materials which are processed or come into contact with magnets, can easily
become magnetized. Other causes include welding, grinding, bending, machining, deep drawing
and even mechanical vibrations and magnetic particle testing. Depending on the type of material
structure, alloy, this magnetism may be retained in the object. The consequences of residual
magnetism may be desirable, problematic or even very costly. A nut that clings to the end of a
screwdriver is handy. Having two products stick together in welding is an undesirable situation;
this interrupts production and therefore costs time and money.
Unwanted residual magnetism can cause many problems in a production process, such as:
products sticking together in a weld;
a rough surface after welding;
welding impossible or with difficulty;
welds that only penetrate on one side;
metal chips that stick to parts or tools;
detection errors by magnetic sensors;
imperfections and thickness differences;
adherence of extra dirt and dust.
In other words: undesired residual magnetism costs time and money and has a negative impact
on the quality of finished products.
Strength and Effect
Field strength (gauss) Effect
>200 Permanent magnet
20-40 Paperclip sticks
>15 Small metal components stick
>10 Small metal shavings stick
>4 Metal dust sticks
40-50 Interferes with arc welding
0,3-0,6 Field strength of the Earth
Magnetic arc blow can be a serious issue with welding jobs. Arc blow can stop a job dead in its
tracks - no good welds so no progress. This can be a great frustration to welders and result in very
expensive project delays. Arc deflection, or indeed extinction away from the point of welding due
to magnetism, is generally referred to as arc blow. This may result in poor quality welding and
usually occurs if the material being welded has residual magnetism. The effect occurs because of
the interaction between the magnetic field of the welding arc and the field of the residual
magnetism. The effect is most pronounced in ferromagnetic steels and although the magnetism
in the material (measured in air at the end of the tubes) may only be a few tens of gauss, after fit
up, the field becomes concentrated in the gap between the two tubes. In this situation the field
may reach very high value. The effect of the magnetic field depends on the welding process but
a good estimate is to assume that fields greater than 30 gauss will cause problems.
Magnetism is undesirable wherever steel is being welded. Residual magnetism in a component
results in an unstable and deflected arc. The effect may be so great that welding is impossible.
Magnetism in the workpiece causes instability of the arc, uneven droplet detachment, heavy
spatter formation, and uneven sidewall fusion. Inadequate welding results mean considerable
finishing work, loss of time and high additional expenses. Hence demagnetisation reduce
expenses, conserve resources and increase quality through high-quality welding results,
minimising finishing work and reducing material and consumables. The objective of
demagnetization is to reduce the residual magnetism not to exceed 3G.
3.0 EFFECT OF RESIDUAL MAGNETISM DURING ARC WELDING
During welding, high-temperature plasma is created between cathode and anode by the ionized
gas and freely moving charge carriers. The plasma column is infinitely mobile and behaves like an
electrical conductor towards electrical and magnetic fields and it is sensitive to electrical and
magnetic interference. If a critical magnetic flux density B exists in the material to be welded, the
plasma column is attracted or repelled, depending on the polarity. The arc is then deflected,
irrespective of the welding torch position, and behaves unstably. As a result of arc deflection,
energy cannot be applied where it is needed. From the user's point of view, all this leads to
insufficient welding results, a great amount of finishing work and to repair or reject hence lead
to serious losses in quality and economy. Prevailing magnetism affects arc processes differently
depending upon the strength B. At levels of 30 to 50 G, arc deflection already results in the fusion
faces not being adequately melted. Shielding gas coverage is not guaranteed as welding
consumables are being fed in. This results in the formation of pores in the weld pool, which in
turn requires reworking or scrapping. Starting at about 80 G, it becomes nearly impossible to
control the process as well. The result is spatter formation and with strong magnetic fields, arc
interruption, re-ignition and thus defects in the weld seam.
4.0 DEMAGNETISATION IN PRACTICE
Preliminary considerations make it clear that ferromagnetic materials can be demagnetized by
passing current in suitable direction and thus generating an opposing magnetic field or a
decreasing alternating field. Possible variations are available to users in day-to-day work for this
purpose.
Page 19 of 25
Magnetism caused by the mechanical separation of components, edge preparation for welding
or due to grinding processes occurs. The first sign of magnetism is the appearance of furring with
iron filings/powder arranged in the shape of a Christmas tree on a component. This is an
indication to the welder of the risk of arc deflection during the welding process. For high-quality
welding results, demagnetisation is recommended after part/edge preparation and before the
actual welding process.
A tube sample with prevailing magnetism which affects welding is demagnetized by the following
method. Copper cable is wound around the pipe (N turns). Copper cable coiling is done in an area
relevant to the welding process, i.e. near the weld seam to be created. A current I, which after a
certain time changes its direction of flow and also its amplitude to a lower value, is sent through
the windings around the tube. The amplitude of the current is reduced each time it passes
through the cable. As a result of this process, the magnetic field strength B and thus also the
residual magnetism in the material, is reduced to near zero ensuring by field indicator (Gauss
meter). Same effect of reducing current may also be achieved by moving the coil away from the
area of interest (withdrawal method). As a basic principle, however, the greater the number of
turns around the component, the more the residual magnetism is reduced. It is not possible to
make a thumb rule regarding exactly how many number of turns and maximum current to start
demagnetization since it depends on the existing magnetism, the material thickness and the
component length. Approximately 10 to 20 turns and 500 to 600 Amps DC have served the
purpose and the residual magnetism is reduced below comfortable level like less than 3 G.
SUMMARY
Arc deflection caused by magnetism is a known problem in joining technology. Due to its sporadic
occurrence, it is necessary to provide welders with fast and reliable methods in day-to-day work.
Simple demagnetizing technique with available facilities has been tried successfully.
Demagnetising technique is customized for the specific tube butt weld in the production line and
demonstrated for effective usage by production personnel very easily.
Figure 01 Workpiece magnetised » Heavy arc deflection Figure 02 Demagnetised » No arc deflection
Figure 03 Coil Winding
USE OF TIP-TIG TECHNOLOGY IN PROCESS EQUIPMENT PLANTS
Rakesh Choudhary & Mr. Plasch#
Head WAPS, Ador Welding Limited, Pune, India
#TiP-TiG Austria.
ABSTRACT
TIP-TIG welding is a new advanced innovation of the common GTAW Process. This process uses
new, patent-pending technology (TiPTiG), that delivers the highest possible weld energy with
the lowest possible weld heat, all while still being user-friendly.
WHAT IS TIPTIG WELDING?
TiPTiG new welding with a hot wire process that can be used in every industry. It is very simple
to learn, use and simple to teach. This process is so unique that higher travel speed, lower heat
input, reduced cycle time, and an overall better-quality welding advantage can be easily
achieved. The TIP-TIG welding
The TIG weld receptivity for higher weld deposition rates is done by decreasing the speeds for
the weld solidification process and increasing the fluid weld area. This allows for a 100%-400%
increase in TIG wire feed rates, increasing the overall weld deposits. All these attributes like faster
speeds and higher than normal weld energy, increase the resulting TIG weld quality and overall
process productivity.
The process is also slag free and uses the lowest possible heat input of any welding process,
producing a Heat Affected Zone (HAZ), all of which help to reduce distortion and weld stress. It
produces some of the highest quality products with the best metallurgical and mechanical
properties on all alloys, but also increases production up to four times the normal speed. There
is also no inter pass cleaning, creating availability for an increased Arc on time and weld quality.
The TIP TIG process is available in manual and automated capability to attain weld and clad
quality levels way beyond the conventional TIG – Hot – Cold Wire TIG – Pulsed MIG and the Flux
Cored process.
HOW IT WORKS?
A TIP TIG welding system uses a
wire fed GTAW system just like a
typical TIG system, but it’s
distinctive for the vibratory effect
on wire at weld pool which is
achieved by a linear forward and
backward mechanical motion
created by the customised wire
feeder system. The forward and
backward motion of the filler wire creates an oscillation that is then transferred to the weld,
Page 21 of 25
agitating the molten weld pool and ultimately disrupting the surface tension. In addition to this
vibratory effect on the wire, a hotwire current (powered by a secondary power source) is also
applied to the filler metal, prior to entering the weld puddle. Above two pictures describes the
weld finish with Manual GTAW & Manual TIP-TIG process.
BENEFITS OF THE TIPTIG WELDING PROCESS
1. Increased fluidity of the weld pool
2. Greater tolerance to joint fit-up
3. Significantly reduced joint sensitivity
4. Greater ability to accept more wire into the weld pool, result in a higher deposition
5. 4-6 times increased travel times
6. Reduced cycle time and heat input
7. Cleaner welds with agitated weld pool
8. Reduced weld stress with the reduced heat input
APPROVED ALLOYS
TiPTiG welding can work on a wide range of alloys such as carbon steel, stainless steel, duplex
and super duplex stainless steels, Inconel, Titanium, Aluminum, Copper, Nickel, and many others
critical materials like P-91, which are used in process plant production.
HEAT EXCHANGERS
Heat Exchangers are commonly constructed from low Carbon Steel, Copper, Copper-Nickel,
Stainless Steel, Hastelloy, Inconel, or Titanium. There are certainly some unique applications and
challenges associated with the welding of heat exchangers, such as the position and access for
the popular circumferential welding of Tube to sheet welds or the half tube shell welding.
A trained TIP TIG welder can typically weld a 50mm tube in 30 seconds… or less with the highest
quality and lowest heat input. Our typical travel speed for fillet welds will be between 300 to 500
mm/min on most applications. Compared with 80 to 150 mm/ min with conventional GTAW
TiPTiG manual system is a low cost semi-automatic solution to tackle any job by selecting a wide
variety of torches for different applications, with modified 180 deg torch it allows a complete
tube sheet welds without repositioning the wire or
stopping, allowing for defect free welds.
The typical customers in the manufacturing and
repair of various sized heat exchangers are in
power plants, chemical plants, petrochemical
plants, petroleum refineries, natural gas
processing, and sewage treatment.
INCONEL CLADDING
Normally, when you manually clad the end of a pipe
ID with Inconel using Pulsed MIG as shown on the
picture and result is often not so good. However
when we use TIP TIG, the results are visible as shown
on the mentioned pictures.
In the pic TiPTiG cladded Job, TIP TIG Inconel 800
pipe was welded with Inconel 82 wire on 10 inch pipe
3/4 Wall, The TIP TIG weld cycle time for the Inconel
pipe was 40 – 50 minutes, whereas the customer
used to take around 4 hrs with regular TIG. When
your weld process can weld a complex incoloy* pipe
and make the welds look simple, that’s a process that
should be given consideration. With TIP TIG, no
brushing, no grinding, no spatter, no weld rework, no
feeding a wire, no foot control, less skills. Note weld
smoke prep machining lubricants. (*Incoloy refers to
a range of superalloys produced by the Special
Metals Corporation group of companies. They are
mostly nickel-based, and designed for excellent
corrosion resistance as well as strength at high temperatures; there are specific alloys for
resistance to chemical attacks)
DUPLEX STEEL WELDING APPLICATIONS
Application: Adjacent picture is of a very thin
Gage Duplex Boilers With traditional
automated TIG process with cold wire may
result sluggish duplex welds.
The customer typically attained a maximum
Hot Wire TIG weld travel speeds from 12 – 15
inch/min.
Then the customer switched over from Hot
Wire TIG to the TIP TIG process. The TIP TIG weld parameters and speeds were achieved using a
0.035 (1mm) 2205 Duplex wire, with TIP TIG travel speed of 35 inch/min was achieved providing
200% increase in weld travel. The welds had a superior, less sluggish weld bead appearance and
the parts had a dramatic reduction in weld distortion, (note the much smaller HAZ). Also the TIP
TIG process was much more stable and consistent.
TIP TIG produces the cleanest welds from lowest possible oxidation. The welds will have the
lowest possible weld pores and inclusions and the smallest possible weld HAZ.
Page 23 of 25
WELDING OF P-91 MATERIAL
Welding of Grade 91 (9Cr-1Mo-V) chromium-molybdenum steel has presented numerous
challenges since its introduction in the 1970s. The gas tungsten-arc (GTAW) process can produce
welds of high quality; however, manual welding can be expensive and labor intensive, requiring
skilled welders with extreme hand-eye coordination and dexterity. Grade 91 productivity can be
increased in either shop or field fabrication by introducing a semiautomatic high deposition metal
transfer (HDMT) GTAW welding process that combines controlled excitation of wire with a hot
wire addition. This technique is cost effective and can be used for the entire weld from root to
cap while producing high quality welds that industry expects from the GTAW process.
With TiP-TiG weld study, it indicates that semiautomatic HDMT GTAW welding process is capable
of producing toughness values comparable to or exceeding manual GTAW and that the process
provides an attractive alternative for welding P91 root and hot passes or the entire weld from
root to cap. Results of this study indicates that semiautomatic HDMT GTAW welding process is
capable of producing impact values comparable to or exceeding manual GTAWT. The process also
provides an attractive alternative for welding P91 root and hot passes or the entire weld from
root to cap. The semiautomatic HDMT GTAW welding process permits an increase in energy (heat
input), larger weld puddle and increased deposition rate while still providing tempering of the
previously deposited weld beads or layers.
TIPTIG HDMT (HIGH DYNAMIC METAL TRANSFER) FOCUS
TIPTIG HDMT FOCUS is a unique TIPTIG welding process its precision and reliability make the
TIPTIG HDMT FOCUS welding process particularly suitable for automated applications in
combination with linear axles, robots and other guiding systems. Nearly all steels, non-ferrous
metals or galvanized sheets can be welded in one layer with filler material; e.g. CrNi-steels with
a material thickness of up to 10 to 12 mm can be welded in single pass without any Joint
preparation. Some of the welded examples are listed below.
It has also been tested that elimination of backing gas in austenitic stainless steel welds using
high deposition metal transfer gas tungsten-arc welding (HDMTGTAW)
TIPTIG HDMT FOCUS PROCESS
Example:
Material: CrNi 8+8 mm
Weld current: 500 A
Weld speed: 46 cm/min
Wire feed speed: 2,0m/min
Below welded samples details are:
Material: CrNi 10+10 mm
Weld current: 500 A
Weld speed: 32 cm/min
Wire feed speed: 1.8
m/min
TIP TIG REDUCED COSTS BY OVER 60%, WHEN COMPARED WITH CONVENTIONAL TIG PROCESS
TIP TIG Cost Comparison
The following comparison shows the actual savings calculated on a real stainless-steel welding
application comparing conventional TIG and TIP TIG on a pipe application (2″ Sch 80 Stainless) in
the 5G position.
Variable / Results Units Conventional TIG TIP TIG Process
Welding process GTAW GTAW
Wire type ER308L ER308L
Wire size mm 2.4 0.9
Wire deposition
speed mm/min 100 1900
Melt off rate g/h 200 580 (3 times)
Deposition efficiency % 100.00% 100.00%
Deposition rate g/h 200 580 (3 times)
Duty cycle % 100.00% 100.00%
Final deposition rate g/h 200 580 (3 times)
Gas type Argon Argon
Flow rate cfh 30 30
Gas/Wire ratio cf/g 63.05 23.62 (60% Reduction
in gas per gm of wire)
The above data shows, the deposition rates approx. 3 times to standard TIG process which
reduces the production costs by 60%
Page 25 of 25
CONCLUSION
TiPTiG is an innovative TIG process and good alternative to standard gas tungsten-arc (GTAW)
process. Its versatility and simplicity makes the manual welder to give higher output. The
Automated High Deposition Metal Transfer (HDMT) GTAW welding process that combines
controlled excitation of wire with a hot wire addition is gives very promising results to challenging
applications.
Plant equipment manufacturing wherever GTAW is applicable, are possible to be replaced by
TiPTiG process which gives very high output without compromising on quality. The success in P91
welding with TiPTiG, also increases the application possibility in that area.
References
1. Paper on ACHIEVING TOUGHNESS IN P91 WELDS FROM ROOT TO CAP USING SEMIAUTOMATIC HIGH
DEPOSITION METAL TRANSFER (HDMT) GTAW WELDING PROCESS by Charles W. “Pat” Patrick
2. Information from TiP TiG USA
3. Information from TiP TiG International AG
Recommended