Metrode 410NiMo for Hydroelectric

Power Plant Applications

Contents

Page

1. Introduction 1

2. Design of a Hydroelectric Power Plant 2

3. Wear Mechanisms 3

4. Materials 4

5. Filler Materials for 410NiMo Martensitic Stainless Steels 5

6. Welding Process Recommendations 10

7. Procedural Guidelines 11

8. References 12

Appendix 1 - Data Sheets

Metrode 410NiMo for Hydroelectric

Power Plant Applications

1. Introduction

The industrialised nations of the world have been criticised in recent times for releasing high concentrations of green house gases into the atmosphere. The regulations of the Kyoto Protocol have introduced additional restrictions; hence greater interest is being shown in making use of non-polluting energy sources. In this spectrum, hydroelectric power plants are continuously gaining in importance as a renewable and non-polluting source of electricity generation. Worldwide, hydroelectric power plants produce about a quarter of the world's electricity and supply more than one billion people with power. The world's hydropower plants output a combined total of 675 gigawatts, the energy equivalent of 3.6 billion barrels of oil, according to the National Renewable Energy Laboratory [1]. Hydroelectric power plants form a very important part of the overall electricity system for many different countries. For example in New Zealand, approximately 80% of power is generated by hydroelectric power plants [2].

2. Design of a Hydroelectric Power Plant

The idea of using water for power generation goes back thousands of years. More than 2,000 years ago, the Greeks are said to have used a water wheel for grinding wheat into flour. These ancient water wheels are like the turbines of today, spinning as a stream of water hits the blades. While the gears of the spinning wheel ground the wheat into flour in those days, spinning turbine blades turn the generator which produces electricity in the modern world (Figure 1).

Figure 1: Electricity generation in a hydropower plant

The three main types of turbine for hydroelectric power plants are Pelton wheels (Figure 2), Francis turbines (Figure 3), and Kaplan turbines (Figure 4); the most common is the Francis turbine runner. The Francis turbine operates with a pressure head of between 30 and 60 metres and has a high operating efficiency (approximately 90%) over a wide range of head heights and flow rates. The size of a Francis turbine runner can range from less than one metre to over fifteen metres in diameter. The selection of the type of turbine runner is based on the water resource variables depending on local conditions. For example, pressure gradient, water velocity, turbulence, local terrain etc, are considered in order to optimise the available energy.

3. Wear Mechanisms

Underwater turbine components; mainly runners, blades, guide vanes, spiral case, head cover, bottom ring etc. come directly under the attack of water jet and wear occurs by corrosion, erosion and cavitation.

Erosion wear is a kind of metal cutting process due to highly particle loaded water. The most important factors influencing erosion are the content, the mass, the hardness, the relative velocity and the angle of attack of the particles. Cavitation on the other hand is a form of surface fatigue. Cavitation is generally associated with high head and varying load and tail water values. Both wear types, erosion and cavitation, may occur at the same time and reinforce each other.

Figure 2: Pelton turbine

Figure 3: Francis turbine Figure 4: Kaplan turbine

Examination of the runner of a hydraulic turbine, or the impellor of a pump, often shows pitted areas in various stages of development. Pitted areas may also be found on turbine or pump water passage surfaces where water velocities are high; this damage is generally termed cavitation erosion or impingement erosion. Because of various physical conditions present in water flow systems, extreme low-pressure areas are produced by flow irregularities. These low pressure areas generate pockets, or cavities, of vapour which grow very rapidly (from approximately 106/sec and from 0.1mm in size). Due to abrupt changes of pressure and flow conditions, the pockets or "cavities" collapse causing high shock pressures which can approach 1500MPa. This value exceeds the yield strength of most materials, and produces permanent deformation. The repetitive formation and collapse of cavities generates shock waves at a regular frequency, which subject the neighboring surface material to a combination of impact and low-cycle fatigue stresses. The resultant impact produces elastic and plastic deformation and after some time the metal surface develops a network of small cracks. Joining cracks tear out bits of the metal and erosion occurs leaving behind a pit. Cavitation causes surface penetration damage of up to 10mm per year to critical components such as impellors, turbine blades, and casings [3]. The end result is a reduction in energy extraction capacity that can lead to losses in terms of downtime, productivity and efficiency.

The normal life of a hydroelectric power station is 30-35 years after which renovation becomes necessary. But plants located in the Himalayan region, the European Alps, the Andes or the Yellow River in China suffer heavy silt erosion, especially during monsoon season. Highly abrasive silt laden water containing a high percentage of quartz passes through machines and damages components extensively causing frequent forced outages of the plant.

4. Materials

Selection of the proper material for underwater turbine parts is important for ensuring their long service life and to avoid frequent shut-downs. The materials, apart from meeting other requirements, should be erosion-resistant and possess a good degree of weldability to enable repair welding on site.

Previously mild steel and 13Cr1Ni steels were used for hydro-electric turbine runner and guide vanes but they suffered from excessive erosion and cavitation. Recently martensitic 410NiMo steel has been used; this steel offers good mechanical characteristics, especially good impact value, along with satisfactory machinability, weldability and considerable resistance against erosion and cavitation. When subjected to cavitational stresses a martensitic structure allows good deformation energy absorption due to fine deformation (twinning) mechanisms. During the impact and low-cycle fatigue stresses detachment of particle occurs at the intersection of the deformation twins. Since the twins are relatively small, only small metal particles detach and as a result, the cavitation damage is relatively slow [4]. Yet, combining all these different features is a compromise to a certain extent. Further possibility exists to provide additional protective overlays such as plasma coating in the hydraulically critical zones eg. trailing edges of the blades, outlet edge of guide vanes. A wear surfacing alloy such as austenitic stainless steel has been a traditional solution for many years. With severe cavitational wear, the use of high carbon, cobalt base alloys with relatively high hardness and corrosion resistance has also been used. However cobalt base alloys, as deposited, are more crack sensitive, difficult to grind to contour and are expensive. Commonly used material for various parts of turbine are given in Table 1. Obvious choice appears to be predominantly martensitic 410NiMo steel for critical underwater components, together with austenitic stainless steel selectively.

A hydro turbine operating in silty water needs important consideration and has an increase in thickness of runner blades in the areas prone to erosion. These areas are mainly at runner outlet edges near the skirt in the case of Francis turbines, and near the peripheral section and outlet edges in the case of Kaplan turbines. Erosion damage occurs on the pressure side of blades.

Table 1: Materials used for various parts of turbine

Turbine part Type of steel

Runner 410NiMo stainless steel

Labyrinth seals 410NiMo or 304L stainless steel

Guide vane 410NiMo stainless steel

Guide vane sealing rings Martensitic forged 16Cr - 5Ni - 0.5Mo stainless steel

Guide vane bush housing Cast steel

Liners for top cover and pivot ring 304L stainless steel

Fastners in water path Stainless steel

Tubes for bearing coolers Cupro-nickel

Cheek plates Martensitic forged 16Cr - 5Ni - 0.5Mo stainless steel

5. Filler Materials for 410NiMo Martensitic Stainless Steels

410NiMo type welding consumables have been successfully used for welding of 410NiMo stainless steels. Weld metal of this type greatly overmatches the strength of equivalent parent material and is remarkably resistant to softening during post weld heat treated (PWHT). The 410NiMo weld metal produces a high strength deposit (>760MPa) with better resistance to corrosion, hydro-cavitation, sulphide-induced SCC, and good sub-zero toughness when compared with plain 12%Cr (410) steels. In the PWHT condition the microstructure consists of tempered martensite with some retained austenite.

Metrode's 410NiMo martensitic range includes MMA/SMAW electrodes, MIG/GMAW wires, TIG/GTAW rods, and flux cored wire (Table 2). They can be used for welding hydraulic turbines, valve bodies, pump, and high pressure pipes, where high hardness levels are not acceptable.

Table 2: 410NiMo welding consumables for 410NiMo martensitic stainless steel

Process Metrode

Consumable AWS EN ISO C Mn Si Cr Ni Mo

MMA 13.4.Mo.L.R 13.4.Mo.L.B

E410NiMo-26 E410NiMo-25

E 13 4 R 52 E 13 4 B 62

0.030.03

0.8 0.7

0.250.25

12.0 12.0

4.5 4.5

0.6 0.6

TIG/MIG ER410NiMo (ER410NiMo)* G/W 13 4 0.02 0.8 0.40 12.3 4.5 0.5

FCW Supercore 410NiMo

E410NiMoT1-1/4 T 13 4 P C/M 2 TS410NiMo-FB1

0.03 0.7 0.40 11.8 4.5 0.5

*Doesnt always meet specification as AWS requires 0.6%Mn maximum and 0.50%Si maximum.

5.1 TIG (GTAW) / MIG (GMAW)

Metrode offers ER410NiMo solid TIG and MIG wires used for manual, semi-mechanised and robotic operations. The TIG wires are available in three different sizes 1.6, 2.0 and 2.4 mm and MIG is produced in 1.2 mm size. The gas shielded processes inherit the advantage of providing a metallurgically clean weld metal with low oxygen, hence low non-metallic inclusion content. This is the reason that the gas-shielded welding processes gas tungsten arc welding (GTAW) / tungsten inert gas (TIG) welding and gas metal arc welding (GMAW) / metal inert gas (MIG) welding - produce good toughness. Along with the good toughness and cleaner weld, the solid wires weld display only small islands of de-oxidation products, making them popular for productive multi-run welding without inter-run de-slagging. Table 3 shows typical mechanical properties of TIG ER410NiMo weld deposits after PWHT 610C/1h.

Table 3: Typical mechanical properties from all-weld metal of TIG ER410NiMo, after PWHT at 610 C/1hr

Properties Test temperature

C (F)

Unit Typical value

Tensile strength +20 (+68) MPa (ksi) 890 (129)

0.2% proof stress +20 (+68) MPa (ksi) 850 (123)

Elongation on 4d +20 (+68) % 23

Elongation on 5d +20 (+68) % 20

Impact energy 0 (+32) J (ft-lbs) 90 (66)

-50 (-58) J (ft-lbs) 60 (44)

Hardness cap/mid +20 (+68) HRC 25-30

+20 (+68) HV 300/305

5.2 MMA (SMAW)

The SMAW process is still widely used for many applications because of its simplicity and adaptability. The process requires relatively simple equipment and does not require a shielding gas, making it an attractive process for site welding. Metrode offers 13.4.Mo.L.R and 13.4.Mo.L.B SMAW electrodes in four different sizes; 2.5, 3.2, 4.0 and 5.0 mm. 13.4.Mo.L.R is a rutile metal powder type made on pure low carbon core wire and 13.4.Mo.L.B is a basic metal powder type made on pure low carbon core wire. The moisture resistant coating provides very low weld metal hydrogen levels and diameters 2.5 and 3.2mm can be used for positional welding. The success of the process is dependent, not only on the characteristics of the electrode, but also the skill of the welder; so electrodes with good operability and welder appeal are of great benefit. Table 4 shows typical mechanical properties of MMA 13.4.Mo.L.R weld deposits.

Table 4: Typical mechanical properties from all-weld metal of MMA 13.4.Mo.L.R, after PWHT at 550 C/2hr

Properties Test temperature

C (F)

Unit Minimum value

PWHT (1) As-welded (2)

Tensile strength +20 (+68) MPa (ksi) 760 (110) 940 (136) 1000 (145)

0.2% Proof stress +20 (+68) MPa (ksi) 500 (73) 695 (101) 780 (113)

Elongation on 4d +20 (+68) % 15 17 4.5

Elongation on 5d +20 (+68) % 15 16 3

Reduction of area +20 (+68) % -- 45 10

Impact energy

+20 (+68) J (ft-lbs) -- 45 (33) 27 (20)

-40 (-40) J (ft-lbs) -- 35 (26) 13 (10)

-60 (-76) J (ft-lbs) -- 30 (22) 8 (6)

Hardness +20 (+68) HV(10) -- 270-300 350

(1) AWS & BS PWHT: 595-620C for 1 hour, air cooled. (2) This weld metal is not usually recommended for use in the as-welded condition, except for surfacing applications

where a hardness of 330-400HV is useful.

5.3 FCAW

Productivity from cored wire welding, regardless of the wire type used, is always superior to that of manual welding with MMA stick electrodes, due to the higher duty cycle. In addition, deposition rates are on a much higher level. In normal duty cycle approximately 20-25% increase in deposition rate is normally achieved with FCW, in comparison to MIG solid wire deposition, operating at 250A. Metrode Supercore 410NiMo is intended more specifically for welding and refurbishing turbine impellers, which require a weld deposit with hardness measurably but not excessively higher (after heat treatment) than the base material. This imparts greater resistance to cavitation wear and sand erosion and effectively reduces the damage caused by continuous pounding from high pressure water.

Metrode Supercore 410NiMo, with a rutile flux system and stainless steel sheath offers not only better operability but also all-positional welding and less post-weld dressing than MMA. This helps to reduce the time required to complete or repair the job especially each individual buckets of pelton runner requiring considerable amount of time. Shielding gas can be Ar/CO2 (15-25% CO2) or CO2 alone. As flux cored wire and metal cored wire welding require the same equipment, switching incurs no additional capital outlay. The wire is available in 1.2 and 1.6 mm diameters.

A number of all-weld metal mechanical tests have been carried out with varying PWHT and these are summarised in Tables 5, 6 and 7.

Table 5: Typical all-weld metal tensile properties of Supercore 410NiMo FCAW

PWHT, C (F)/hour

UTS, MPa (ksi)

0.2% Proof strength, MPa (ksi)

Elongation, % Reduction of area, %

A4 A5

605 (1125)/1 970 (141) 880 (128) 19 16 55

610 (1130)/10 870 (126) 705 (102) 22 18 54

610 (1130)/1 940 (136) 870 (128) 20 18 50

610 (1130)/1 940 (137) 870 (125) 20 18 50

Table 6: All-weld metal impact properties of Supercore 410NiMo FCAW

PWHT, C (F )/hour Test temperature,

C (F)

Impact energy,

J (ft-lbs)

Lateral

expansion, mm

610 (1130)/1 +20 (+68) 46 (34) 0.52

-40 (-40) 25 (18) 0.23

610 (1130)/10 +20 (+68) 50 (37) 0.63

-40 (-40) 42 (31) 0.45

610 (1130)/10

+20 (+68) 53 (39) 0.75

0 (+32) 52 (38) 0.75

-40 (-40) 45 (33) 0.56

610 (1130)/1 +20 (+68) 49 (36) 0.61

-40 (-40) 32 (24) 0.38

650 (1202)/10 + 620 (1150)/10

+20 (+68) 49 (36) 0.66

0 (+32) 46 (34) 0.61

-40 (-40) 37 (27) 0.48

670 (1240)/2 + 610 (1130)/2 -40 (-40) 34 (25) 0.39

690 (1275)/2 + 610 (1130)/2 -40 (-40) 36 (27) 0.42

710 (1310)/2 + 610 (1130)/2 -40 (-40) 42 (31) 0.49

740 (1365)/2 + 610 (1130)/2 -40 (-40) 35 (26) 0.42

770 (1420)/2 + 610 (1130)/2 -40 (-40) 31 (23) 0.42

Table 7: All-weld metal hardness of Supercore 410NiMo FCW

PWHT Hardness, HV(10) Hardness, HRC

C (F)/hour Cap,

average/max Mid-section, average/max

Cap, average/max

Mid-section, average/max

607 (1125)/1 327 / 330 334 / 342 30 / 31 32 / 32

610 (1130)/10 298 / 314 295 / 297 26 / 28 27 / 27

610 (1130)/1 328 / 339 337 / 339 28 / 28 29 / 31

610 (1130)/1 307 / 311 317 / 319 30 / 30 31 / 31

650 (1200)/10 + 620 (1150)/10

298 / 302 314 / 319 - -

670 (1240)/2 + 610 (1130)/2

297 / 304 297 / 309 27 / 27 28 / 29

690 (1275)/2 + 610 (1130)/2

297 / 309 300 / 306 25 / 27 26 / 27

710 (1310)/2 + 610 (1130)/2

308 / 322 307 / 309 27 / 27 27 / 27

740 (1365)/2 + 610 (1130)/2

306 / 317 321 / 333 27 / 28 28 / 28

770 (1420)/2 + 610 (1130)/2

327 / 330 311 / 317 28 / 28 27 / 29

Figure 5: Deposition rate of Metrode Supercore 410NiMo

6. Welding Process Recommendations

A combination of different welding techniques, including manual metal arc welding (MMA), gas tungsten arc welding (GTAW) / tungsten inert gas (TIG) welding or semiautomatic techniques such as gas metal arc welding (GMAW) / metal inert gas (MIG) welding with solid wires or flux cored wires (FCW) is being used. For productivity the semiautomatic processes are most widely used.

The specific choice of method varies depending on factors such as joint geometry, accessibility and the cost of labour, equipment and consumables. Different combinations of welding techniques and consumables will therefore be used for different turbine runners depending on location and the responsible company.

The deposition rate of the Supercore 410NiMo 1.2mm and 1.6mm diameter wires has been assessed by using different process parameters. Tests were carried out both in the flat position (identified as Flat bead on the plate on the graph) and in the vertical position (identified as vertical bead on plate/3F). Tests made on CMn steel using Argoshield Heavy shielding gas (Ar-20%CO2-2%O2). Welding was all manual so stickout varied depending on welding parameters and position. The aim was to try to achieve the highest deposition rate possible in the vertical position whilst maintaining a controllable weld pool and relatively flat weld bead. As the welder became more familiar with the wires he was able to control them in the vertical position at higher currents than he had been able to in earlier tests.

The maximum deposition rate achieved in the vertical position with the Supercore 410NiMo 1.2mm diameter wire was ~5kg/hour and the maximum with the Supercore 410NiMo 1.6mm diameter wire was ~5.5kg/hour. But the parameters used to achieve the 5.5kg/hour with the 1.6mm diameter Supercore 410NiMo wire were far too hot to be used continuously (a more realistic condition produced a deposition rate of ~4.25kg/hour).

The actual deposition rates that can be achieved in production will probably vary depending on the welder, the welding position and the access but overall the 1.2mm diameter wire produces a more controllable weld pool at the higher deposition rate conditions. The bead profile produced with the 1.2mm diameter wire is also flatter and more consistent than that produced with the 1.6mm diameter wires. The deposition rate data is presented in Figure 5.

6.1 TIG (GTAW)

The particular features associated with TIG process are:

suitable for all positions.

enables the precise control essential to achieve single-side root weld deposits both with satisfactory underbead profile. 1.6mm diameter filler wire is recommended for wall thicknesses up to 3mm, and 2.4mm diameter for thicker sections.

Argon gas for both shielding and back-purging is recommended.

6.2 MIG (GMAW)

The particular features associated with MIG process are:

1.2mm diameter wire and, typically, 210-230A, 27-30V spray transfer arc conditions.

high purity Argon + 1-2% O2 or 1-5% CO2. Proprietary gas mixtures with

retained austenite transforms to martensite on application of cavitation stresses, thus absorbing shock energy and reducing cavitation. A hard weld metal is required for good erosion resistance in hydropower plant application, but in sour oil condition, for maximum resistance to sulphide-induced SCC, NACE MR0175 specifies a hardness of 23HRc maximum.

Conformance to the NACE MR0175 hardness limit is often difficult to achieve because weld metal and HAZ are very resistant to softening by PWHT. A double temper for 5-10h is necessary. Common practice is 675C/10h + 605C/10h with intermediate air cool to ambient. Recent work indicates 650C + 620C is optimum, and that intermediate air cooling to ambient or lower is essential. Another authority suggests raising the first PWHT cycle for full austenitisation anneal at 770C/2h prior to final temper. Control of distortion may be more critical in this case. In the case of the Supercore 410NiMo flux cored wire it has not been possible to reduce the hardness to 23HRC irrespective of the PWHT carried out.

If 410NiMo consumables are considered for welding plain 12Cr martensitic stainless steels such as type 410 or CA15, the PWHT should not exceed about 650C unless a second temper at 590-620C is applied.

8. References

1. Bonsor, Kevin. "How Hydropower Plants Work." 06 September 2001. 13 March 2009.

2. Electricity Generation in New Zealand 3/93, Public Relations Group ECNZ, Wellington, NZ.

3. Simoneau, R. The optimum protection of hydraulic turbines against cavitation erosion.12th IAHR Symposium, Stirling, UK, Aug, 1984.

4. Simoneau, R., Lambert, P., Simoneau, M., Dickson, J I and Esprance, G L. Cavitation erosion and deformation mechanisms of Ni and Co austenitic stainless steels (1987).

Rev 09 03/12 DS: B-11 (pg 1 of 5)

Data Sheet B-11 METRODE PRODUCTS LTD HANWORTH LANE, CHERTSEY SURREY, KT16 9LL, UK

Tel: +44(0)1932 566721

410NiMo MARTENSITIC STAINLESS

Fax: +44(0)1932 565168

Email: info@metrode.com

Website: www.metrode.com

Alloy type

12%Cr-4.5%Ni-0.5%Mo (410NiMo) soft martensitic

alloy.

Materials to be welded

wrought cast

ASTM F6NM CA6NM UNS S41500 BS EN / DIN 1.4313 G-X5CrNi 13 4 BS -- 425C11 AFNOR -- Z6 CND 1304-M

Applications

High strength (>760MPa) martensitic stainless steel

with better resistance to corrosion, hydro-cavitation,

sulphide-induced SCC, and good sub-zero toughness

when compared with plain 12%Cr steels (e.g. type

410/CA15).

Weld metal of this type greatly overmatches the

strength of equivalent parent material and is

remarkably resistant to softening during PWHT.

These properties can be exploited for welding

martensitic precipitation-hardening alloys if

corrosion conditions are compatible with lower alloy

weld metal, with the advantage of a single PWHT at

450-620C for tempering. The 410NiMo

consumables are also used for overlaying mild and

CMn steels.

13%Cr-4%Ni alloys are used in cast or forged form

for hydraulic turbines, valve bodies, pump bowls,

compressor cones, impellers and high pressure

pipes in power generation, offshore oil, chemical

and petrochemical industries.

Microstructure

In the PWHT condition the microstructure consists of

tempered martensite with some retained austenite.

Welding guidelines

Preheat-interpass range of 100-200C is

recommended to allow martensite transformation

during welding. Cool to room temperature before

PWHT.

PWHT

For maximum resistance to sulphide-induced SCC in

sour oil conditions NACE MR0175 specifies a

hardness of

Rev 09 03/12 DS: B-11 (pg 2 of 5)

13.4.Mo.L.R Rutile MMA electrode for 410NiMo

Product description Rutile metal powder type made on pure low carbon core wire. Moisture resistant coating giving very low weld metal hydrogen levels. Diameters above 3.2mm are not recommended for positional welding.

Recovery is about 130% with respect to core wire, 65% with respect to whole electrode.

Specifications AWS A5.4 E410NiMo-26 BS EN 1600 E 13 4 R 52

ASME IX Qualification QW432 F-No 1, QW442 A-No 6

Composition C Mn Si S P Cr Ni Mo Cu

(weld metal wt %) min -- -- -- -- -- 11.0 4.0 0.40 -- max 0.06 1.0 0.90 0.025 0.03 12.5 5.0 0.70 0.50

typ 0.03 0.8 0.25 0.01 0.01 12 4.5 0.6 0.05

All-weld mechanical Typical properties min

PWHT (1) As-welded (2)

properties Tensile strength MPa 760 940 1000 0.2% Proof stress MPa 500 695 780 Elongation on 4d % 15 17 4.5 Elongation on 5d % 15 16 3 Reduction of area % -- 45 10 Impact energy + 20C J -- 45 27 - 40C J -- 35 13 - 60C J -- 30 8 Hardness HV -- 270-300 350

(1) AWS & BS PWHT: 595-620C for 1 hour, air cooled. See front page for details on PWHT.

(2) This weld metal is not usually recommended for use in the as-welded condition, except for surfacing applications where a hardness of 330-400HV is useful.

Operating parameters DC +ve or AC (OCV: 70V min)

mm 2.5 3.2 4.0

5.0

min A 70 80 100 140 max A 110 140 180 240

Packaging data mm 2.5 3.2 4.0

5.0

length mm 350 380 450 450 kg/carton 12.6 15.0 18.0 16.8 pieces/carton 570 363 240 171

Storage 3 hermetically sealed ring-pull metal tins per carton, with unlimited shelf life. Direct use from tin is satisfactory for longer than a working shift of 8h. Excessive exposure of electrodes to humid conditions will

cause some moisture pick-up and increase the risk of porosity.

For electrodes that have been exposed: Redry 300 350C/1-2h to restore to as-packed condition. Maximum 420C, 3 cycles, 10h total. Storage of redried electrodes at 50 200C in holding oven or heated quiver: no limit, but maximum 6 weeks

recommended. Recommended ambient storage conditions for opened tins (using plastic lid): < 60% RH, >

18C.

Fume data Fume composition, wt % typical:

Fe Mn Ni Cr Cu Mo V F OES (mg/m3)

18 2 0.5 3

Rev 09 03/12 DS: B-11 (pg 3 of 5)

13.4.Mo.L.B Basic MMA electrode for 410NiMo

Product description Basic metal powder type made on pure low carbon core wire. Moisture resistant coating giving very low weld metal hydrogen levels. Diameters above 3.2mm are not recommended for positional welding.

Recovery is about 130% with respect to core wire, 65% with respect to whole electrode.

Specifications AWS A5.4 E410NiMo-25 BS EN 1600 E 13 4 B 62

ASME IX Qualification QW432 F-No 1, QW442 A-No 6

Composition C Mn Si S P Cr Ni Mo Cu

(weld metal wt %) min -- -- -- -- -- 11.0 4.0 0.40 -- max 0.06 1.0 0.90 0.025 0.03 12.5 5.0 0.70 0.50

typ 0.03 0.7 0.25 0.01 0.01 12 4.5 0.6 0.05

All-weld mechanical Typical properties min

PWHT (1)

properties Tensile strength MPa 760 900 0.2% Proof stress MPa 500 650 Elongation on 4d % 15 17 Elongation on 5d % 15 16 Reduction of area % -- 45 Impact energy + 20C J -- 50

(1) AWS PWHT: 595-620C for 1 hour, air cooled. See front page for details on PWHT.

Operating parameters DC +ve

mm 2.5 3.2 4.0

5.0

min A 70 80 100 140 max A 110 140 180 240

Packaging data mm 2.5 3.2 4.0

5.0

length mm 350 380 450 450 kg/carton 12.6 13.5 16.5 17.1 pieces/carton 570 375 225 156

Storage 3 hermetically sealed ring-pull metal tins per carton, with unlimited shelf life. Direct use from tin is satisfactory for longer than a working shift of 8h. Excessive exposure of electrodes to humid conditions will

cause some moisture pick-up and increase the risk of porosity.

For electrodes that have been exposed: Redry 300 350C/1-2h to restore to as-packed condition. Maximum 420C, 3 cycles, 10h total. Storage of redried electrodes at 50 200C in holding oven or heated quiver: no limit, but maximum 6 weeks

recommended. Recommended ambient storage conditions for opened tins (using plastic lid): < 60% RH, >

18C.

Fume data Fume composition, wt % typical:

Fe Mn Ni Cr Cu Mo V F OES (mg/m3)

18 2 0.5 3

Rev 09 03/12 DS: B-11 (pg 4 of 5)

ER410NiMo Solid wire for welding 410NiMo martensitic stainless steel

Product description Solid wire for TIG and MIG.

Specifications AWS A5.9 (ER410NiMo) Does not always strictly conform see composition. BS EN ISO 14343-A 13 4 BS EN ISO 14343-B (SS410NiMo)

ASME IX Qualification QW432 F-No 6, QW442 A-No 6

Composition C Mn * Si * S P Cr Ni Mo Cu

(wire wt %) min -- 0.4 -- -- -- 11.0 4.0 0.4 -- max 0.05 1.0 0.60 0.02 0.03 12.5 5.0 0.7 0.3

typ 0.02 0.8 0.4 0.005 0.015 12.3 4.5 0.5 0.1

* AWS requires 0.6%Mn max and 0.50%Si max.

All-weld mechanical Typical values after PWHT 610C/1h: TIG

properties Tensile strength MPa 890 0.2% Proof stress MPa 850 Elongation on 4d % 23 Elongation on 5d % 20 Impact energy 0C J 90 -50C J 60 Hardness cap/mid HRC 25-30 HV 300

Typical operating TIG MIG

parameters Shielding Argon *

Ar with 1-2%O2

or 1-5%CO2 **

Current DC- DC+ Diameter 2.4mm 1.2mm Parameters 100A, 12V 220A, 28V * Also required as a purge for root runs. ** Proprietary gas mixtures with

Rev 09 03/12 DS: B-11 (pg 5 of 5)

SUPERCORE 410NiMo Flux cored wire for welding 410NiMo martensitic stainless steel

Product description All-positional rutile flux cored wire made on a high purity stainless steel strip

Metal recovery about 90% with respect to wire.

Specifications AWS A5.22 E410NiMoT1-1/4 BS EN ISO 17633-A T 13 4 P C/M 2 BS EN ISO 17633-B TS410NiMo-FB1

ASME IX Qualification QW432 F-No 6, QW442 A-No 6

Composition C Mn Si S P Cr Ni Mo Cu Co

(weld metal wt %) min -- -- -- -- -- 11.0 4.0 0.4 -- -- max 0.06 1.0 1.0 0.025 0.030 12.5 5.0 0.7 0.3 0.05

Typ 0.03 0.7 0.4 0.005 0.017 11.8 4.5 0.5 0.03 0.03

All-weld mechanical Typical values: Min 610C/1h 610C/10h 650C/10h +620C/10h

properties Tensile strength MPa 760 940 870 -- 0.2% Proof stress MPa 500 850 700 -- Elongation on 4d % 15 20 23 -- Elongation on 5d % 15 17 19 -- Reduction of area % -- 50 55 -- Impact energy + 20C J -- 45 50 50 - 40C J -- 30 40 35 Hardness HV -- 330 310 310 HRC -- 31 27 28

AWS PWHT = 593-621C/1 hour. BS EN PWHT = 580-620C/2 hours.

Operating parameters Shielding gas Ar-20%CO2 or 100% CO2 at 20-25l/min. Current DC+ve parameters as below (for 100%CO2 increase voltage by 1-3V):

mm range typical stickout

1.2 150-280A, 25-32V 180A, 29V 15-25mm 1.6 200-350A, 26-34V 260A, 30V 15-25mm

Packaging data Spools vacuum-sealed in barrier foil with cardboard carton: 15kg The as-packed shelf life is virtually indefinite. Resistance to moisture absorption is high, but to maintain the high integrity of the wire surface and prevent any

possibility of porosity, it is advised that part-used spools are returned to polythene wrappers.

Where possible, preferred storage conditions are 60% RH max, 18C min.

Fume data Fume composition (wt %):

Fe Mn CrVI

Ni Mo

Cu OES (mg/m3)

18 3 2.5 1 0.2