WELDING ELECTRODESWELDING ELECTRODES

GUIDED BY :- PRESENTED BY :-GUIDED BY :- PRESENTED BY :-

Mr. SHAILENDRA PUROHIT ANKUR PATNI Mr. SHAILENDRA PUROHIT ANKUR PATNI Mr.AJAY SHEKHAR Mr.AJAY SHEKHAR BHARULAL AHIRBHARULAL AHIR

JUGAL KISHOR PATIDARJUGAL KISHOR PATIDAR

SATISH BANSIYASATISH BANSIYA

SHRI G.S INSTITUTE OF TECHNOLOGY AND SCIENCE

D&H PROFILED&H PROFILE

D&H Sécheron Electrodes Pvt. Ltd, a D&H Sécheron Electrodes Pvt. Ltd, a privately owned company, is in the privately owned company, is in the welding industry field since 1966.welding industry field since 1966.

D&H Sécheron Electrodes Pvt. Ltd is D&H Sécheron Electrodes Pvt. Ltd is specialized in the manufacturing of specialized in the manufacturing of Welding Consumables such as Welding Welding Consumables such as Welding Electrodes, MIG Welding Wires, Flux Electrodes, MIG Welding Wires, Flux Cored Wires and Gas Welding Rods. Cored Wires and Gas Welding Rods. Through their sales network, they cover a Through their sales network, they cover a record 70% of the local market .record 70% of the local market .

WHAT IS ELECTRODEWHAT IS ELECTRODE

ELECTRODE

COSUMABLE NON CONSUMABLE

The electrode may be defined as “it is metal of The electrode may be defined as “it is metal of which the sole purpose to carry the current and which the sole purpose to carry the current and sustain the electric arc between its tip and base sustain the electric arc between its tip and base metal as well as in some cases it melts and metal as well as in some cases it melts and supplies filler metal addition in the proposed supplies filler metal addition in the proposed joint.”joint.”

Electrode can be divided into two groups Electrode can be divided into two groups depending upon their functions which are given depending upon their functions which are given

below. below.

ELECTRODES TYPES ELECTRODES TYPES

ELECTRODEELECTRODE

BASED UPON MATERIALS BASED UPON COATING

1.mild steel electrodes 2.low alloy steel electrodes 3.stainless steel electrodes 4.electrodes for cast iron 5.copper and copper alloy

electrode 6.nickel and nickel alloy electrode7.aluminium and aluminium alloy

electrode

BASED UPON MATERIALBASED UPON MATERIAL

BASED ON COATING BASED ON COATING

Cellulose type Cellulose type Rutile type Rutile type Acid type Acid type Oxidizing type Oxidizing type Basic type Basic type

CELLULOSE TYPE CELLULOSE TYPE

The cellulose is a organic material which The cellulose is a organic material which contain 30 % in the electrode coating by weight. contain 30 % in the electrode coating by weight. It decomposes in the arc and produce a gas It decomposes in the arc and produce a gas shield which protects arc from atmospheric shield which protects arc from atmospheric oxygen and nitrogen.oxygen and nitrogen.

Electrodes which have cellulose content Electrodes which have cellulose content impart deep penetration & increased electrode impart deep penetration & increased electrode burn off rate.burn off rate.

RUTILE TYPE RUTILE TYPE

Rutile (titania) electrode give a smooth & Rutile (titania) electrode give a smooth & quiet arc, negligible spatter, & easily quiet arc, negligible spatter, & easily removable slag. The electrode will work removable slag. The electrode will work on both AC & DC. Generally use for on both AC & DC. Generally use for vertical and overhead positions. vertical and overhead positions.

ACID TYPE ACID TYPE

This type of coating contain iron-oxide as This type of coating contain iron-oxide as a major constituent. During welding it a major constituent. During welding it produce a iron-manganese oxide –silica produce a iron-manganese oxide –silica fluid slag whose metallurgical effect is fluid slag whose metallurgical effect is acidic. This slag solidifies like honey- acidic. This slag solidifies like honey- combstructure and easily detached. combstructure and easily detached.

OXIDIZING TYPE OXIDIZING TYPE

It contain mainly iron-oxide and silicates It contain mainly iron-oxide and silicates with or with out manganese oxides. it with or with out manganese oxides. it produce a heavy slag which has oxidizing produce a heavy slag which has oxidizing properties. properties.

ThisThis type electrode is limited in use type electrode is limited in use because the resultant weld metal is soft because the resultant weld metal is soft and low mechanical properties. and low mechanical properties.

BASIC TYPE BASIC TYPE This type of coating contains calcium This type of coating contains calcium

carbonates (CaCo3), calcium fluoride carbonates (CaCo3), calcium fluoride (CaF2) & metal powder . (CaF2) & metal powder .

This results in a chemically basic slag, This results in a chemically basic slag, which is fairly fluid. which is fairly fluid.

The electrodes having this type of coating The electrodes having this type of coating is preferred to use for minimize the risk is preferred to use for minimize the risk of hydrogen-induced cracking or cold of hydrogen-induced cracking or cold cracking in the base metal. cracking in the base metal.

TYPE OF COATINGTYPE OF COATING

Coating factor =Dia. of the electrode/dia. Coating factor =Dia. of the electrode/dia. of core wireof core wire

Lightly coated electrodes: Electrodes with Lightly coated electrodes: Electrodes with a coating factor approx 1.25 .a coating factor approx 1.25 .

Medium coated electrodes: Electrodes Medium coated electrodes: Electrodes with a coating factor about1.45.with a coating factor about1.45.

Heavily coated electrodes: The coating Heavily coated electrodes: The coating factor is between 1.6&2.2.factor is between 1.6&2.2.

NOMENCLATURE(AWS)NOMENCLATURE(AWS)

EEXXXXXXXX first two numbers refer to first two numbers refer to tensile strengthtensile strength of the deposited weld of the deposited weld metal. metal.

for example : Efor example : E60601010

“ “60”60” means 60, 000 psi tensile strength means 60, 000 psi tensile strength of the deposited weld metal. of the deposited weld metal.

EXX XX third number is denoting the position in which the electrode can be used.

example: “1” for all position (f, v, oh,h)“2” for flat and h-fillet position.“3” for flat only.

EXXEXXXXXX last number refers to last number refers to chemical compositionchemical composition present in the present in the electrode coating. for example :electrode coating. for example :

““0” 0” cellulose- sodiumcellulose- sodium ““1” 1” cellulose- potassiumcellulose- potassium ““2” 2” rutile –sodiumrutile –sodium ““3” 3” rutile – potassiumrutile – potassium ““4” 4” rutile iron powderrutile iron powder ““5,6,8” low hydrogen 5,6,8” low hydrogen

Manufacture of electrodeManufacture of electrode

1.1. Wires of different composition are Wires of different composition are obtained.obtained.

2.2. Cut wire into different Cut wire into different lengths(300,350, 450 mm etc.)lengths(300,350, 450 mm etc.)

3.3. Flux coating ->Flux coating -> Dipping method Dipping method Extrusion methodExtrusion method

DRYING OF ELECTRODE DRYING OF ELECTRODE

All electrodes must All electrodes must be dried to the right be dried to the right level to perform level to perform properly. Even a small properly. Even a small amount of moisture in amount of moisture in electrodes can lead to electrodes can lead to major weld problems major weld problems such as internal such as internal porosity, weld cracking porosity, weld cracking or poor operating or poor operating characteristics. characteristics.

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Selection of electrodesSelection of electrodes1.1. Chemical composition of base metalChemical composition of base metal

2.2. Thickness of work pieceThickness of work piece

3.3. Nature of the electrode coating Nature of the electrode coating (cellulose, rutile ,low hydrogen etc)(cellulose, rutile ,low hydrogen etc)

4.4. Position(flat ,horizontal ,vertical ,overPosition(flat ,horizontal ,vertical ,overhead)head)

5.5. Type of joint(lap ,butt ,fillet ,etc.)Type of joint(lap ,butt ,fillet ,etc.)

6.6. Type of power source(AC and DC)Type of power source(AC and DC)

7.7. Type of polarity(DCSP ,DCRP)Type of polarity(DCSP ,DCRP)

Selection of electrodesSelection of electrodes

8.8. Weld bead geometry and shape of the Weld bead geometry and shape of the weld bead surface.weld bead surface.

9.9. Amount of weld metal to be deposited Amount of weld metal to be deposited and deposition efficiency of electrode.and deposition efficiency of electrode.

10.10. Surface finish and quality of the weld Surface finish and quality of the weld metal.metal.

11.11. Mechanical and other properties in Mechanical and other properties in the welded joint.the welded joint.

12.12. Cost of electrode.Cost of electrode.

Manganese(Mn)Manganese(Mn)

1. Atomic weight =54.91. Atomic weight =54.92. Melting point is 1242 C˚2. Melting point is 1242 C˚3. Manganese is used as a deoxidizer in steel 3. Manganese is used as a deoxidizer in steel 4. Manganese increases the hardenability of steel4. Manganese increases the hardenability of steel5. It prevent the formation of iron sulphide which 5. It prevent the formation of iron sulphide which causes hot cracking difficulties causes hot cracking difficulties 6.In carbon steel 1.5% Mn 6.In carbon steel 1.5% Mn 7.Above 1.5% Mn in steel is low alloy steel7.Above 1.5% Mn in steel is low alloy steel8.About 2.5% mn is found in only high-aloy steel8.About 2.5% mn is found in only high-aloy steel

Silicon(Si)Silicon(Si)

1.Atomic weight is 281.Atomic weight is 28

2.Melting point is 14262.Melting point is 1426 C˚C˚

3.It lower the 3.It lower the δδ--γγ transformation and raise the transformation and raise the γγ--αα transformation in iron alloy, so it is called the ferrite transformation in iron alloy, so it is called the ferrite forming element forming element

4.It is deoxidizer element and use to control the oxygen 4.It is deoxidizer element and use to control the oxygen contentcontent

5.Improve hardenability, mechanical property5.Improve hardenability, mechanical property

Phosphorus(P)Phosphorus(P)

1.Atomic weight 31 and melting point is 43.89 C˚1.Atomic weight 31 and melting point is 43.89 C˚

2.Regarded as impurity due to tendency to segregate2.Regarded as impurity due to tendency to segregate

3.Phosphorus has mild beneficial effect on the 3.Phosphorus has mild beneficial effect on the properties of some steelproperties of some steel

4. It is added in amount up to 0.10 % to improve the 4. It is added in amount up to 0.10 % to improve the strength and corrosion resistance of low-alloy high-strength and corrosion resistance of low-alloy high-strength steel. Similar amount help the machineability strength steel. Similar amount help the machineability of many steelof many steel

Sulfur(S)Sulfur(S)

1.Atomic weight is 32 and melting 1.Atomic weight is 32 and melting point is 118.89point is 118.89 C˚ C˚

2.Soluble in molten iron , but due to low boiling 2.Soluble in molten iron , but due to low boiling point can not be held in large quantities.point can not be held in large quantities.

3.Alloying addition of 0.10% to 0.30% improve 3.Alloying addition of 0.10% to 0.30% improve machining properties of steelmachining properties of steel

4.Sulfur present in material causes short pieces 4.Sulfur present in material causes short pieces of chips during machining of parts.of chips during machining of parts.

Molybdenum(Mo)Molybdenum(Mo)

1.Atomic weight 96 and melting point is 1.Atomic weight 96 and melting point is 26202620 C˚ C˚

2.It is stronger ferrite former 2.It is stronger ferrite former

3.In steel strong tendency to form carbide 3.In steel strong tendency to form carbide and improve hardenabilityand improve hardenability

4. 0.25 to 0.30% are adequate to secure 4. 0.25 to 0.30% are adequate to secure high hardenabilityhigh hardenability

5.Mo in alloying steel 0.5 to 1.5% is often 5.Mo in alloying steel 0.5 to 1.5% is often added to improve strength and creep added to improve strength and creep resistenceresistence

Testing of electrodeTesting of electrode

Tension testTension test Bend testBend test Radiography testRadiography test Chemical analysisChemical analysis

Radiography testRadiography test

Radiography is a mature NDT method that can be used to effectively detect several types of discontinuities embedded within a variety of types of materials and components.

The part is placed between the radiation source and a piece of film. The part will stop some of the radiation. Thicker and denser area will stop more of the radiation.

Chemical Composition Analysis Chemical Composition Analysis TestTest

A weld pad for determining the chemical A weld pad for determining the chemical composition of a filler metal must be composition of a filler metal must be prepared.prepared.

Number of layers are required to assure that Number of layers are required to assure that the top surface has no dilution with the base the top surface has no dilution with the base metal.  metal.  

The welds are deposited in the flat position. The welds are deposited in the flat position.  After welding, the top surface is machined or  After welding, the top surface is machined or ground smooth to remove all foreign matter. ground smooth to remove all foreign matter.

  A sample is taken from this surface for A sample is taken from this surface for chemical analysis. chemical analysis.

OUR PROJECTOUR PROJECT

Our project is “to develop inconel Our project is “to develop inconel consumable for overlay application”.consumable for overlay application”.

Overlay: it is a layer of weld material Overlay: it is a layer of weld material put on the base metal.put on the base metal.

Requirements Requirements 1.1. Electrode shall be suitable for use in all position.Electrode shall be suitable for use in all position.

2.2. Electrode when used for overlaying on 1.25Cr-Electrode when used for overlaying on 1.25Cr-0.5Mo material, shall meet the following chemical 0.5Mo material, shall meet the following chemical composition at 2 mm from base metalcomposition at 2 mm from base metal

UTS (Mpa) - 550(min)UTS (Mpa) - 550(min)

% elongation- 30(min)% elongation- 30(min)

C Mn Si S P Cr Mo

0.1 1 to 3.5 0.75 0.015 0.03 13 to 17 0.5 to 2.5

Fe Cu Ni

12 0.5 62 (min)

C Mn Si S P Cr Mo

0.061 0.99 0.51 0.011 0.013 1.25 0.50

Cromotherme-1

1200 T(NS)1200 T(NS)

C Mn Si S P Cr Mo

0.1 1 to 3.5 0.75 0.02 0.03 13 to 17 0.5 to 2.5

Fe Cu Ni

12 0.5 62 (min)

IdentificationAuthorized ByDate

Position

Welding position 1G

Electrical Characteristics

CurrentPolarity

AC/DC+

Technique

Stringer/weave beadMulti/single pass(per Side)Inter-pass cleaning

StringerAs per joint 1Brushing & Grinding

Preheat

Preheat temp.Inter-Pass Temp. (Max.)

Room temp.1000C

Company NameWelding ProcessProcess Type

D&H Secheron Ele. MMAWManual

Joint design used

Joint typeJoint designRoot GapGroove AngleBacking StripRoot Face

Butt WeldSingle V3 mm60o

----2.0 mm

Base Metal

Material specificationPlate lengthPlate widthThickness

BQMS30020022 mm

Filler Metal

Brand NameAWS CodeRedry at

Chromotherme-1E80183000C

Layer &

Size (mm)

Bead / Pass

Process Current

Amps

Voltage (V)

Time (Sec.)

Length of Bead (mm)

Heat Input

KJ/mm

Joint details

1st 3.15*450

1 MMAW 80-85 22-24 270 300 1.70

2nd 4.0*450

1 MMAW

120-125 24-26 260 300 2.65

3rd 4.0*450

1 MMAW 120-125 24-26 148 300 1.51

2 MMAW

120-125 24-26 165 300 1.68

4th 4.0*450

1 MMAW 120-125 24-26 160 300 1.63

2 MMAW

120-125 24-26 170 300

1.73

3 MMAW

120-125 24-26 163 300 1.66

Heat inputHeat input

Heat input =V*I*T/LHeat input =V*I*T/L

where,where,

V=voltage in voltV=voltage in volt

I=current in I=current in amp.amp.

T=time in secT=time in sec

L=bead length L=bead length in mmin mm

More is the heat input more is the More is the heat input more is the carbide formation and hence the carbide formation and hence the following result occur-following result occur-

1.1. Ductility increaseDuctility increase

2.2. Ultimate tensile strength increaseUltimate tensile strength increase

3.3. % elongation decrease% elongation decrease

4.4. Brittleness increaseBrittleness increase

5.5. Impact strength decreaseImpact strength decrease

referencesreferences

http://www.esabna.com/euweb/http://www.esabna.com/euweb/awtc/Lesson10_13.htm.awtc/Lesson10_13.htm.

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