PSI - Issue 14

P D Gosavi et al. / Procedia Structural Integrity 14 (2019) 304–313 P D Gosavi et al./ Structural Integrity Procedia 00 (2018) 000 – 000

306

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metallographic process for machining process to extract &study the weld microstructure and sample extraction for mechanical testing

Table 1. Welding parameters used for carrying out welding of HSLA steel by SMAW, GTAW, SAW and GMAW processes Welding parameters Weld 1 (W1) [SMAW] Weld 2 (W2) [GTAW] Weld (W3) [SAW]

Weld 4 (W4) [GMAW]

Double V-type; Root Gap : 4 +2 -1 mm; Root Face : 0 +2 mm;Included angle : 60 0 +5 0

Weld joint configuration

Welding Position

1G

80% Ar 20% CO 2

Shielding gas/Flux

-

Argon gas 14-18 Litre per minute

Fused Flux

12-16 litre per minute

Shielding gas flow rate

-

-

Current type

DCEP

DCEN

DCEP

DCEP

100-140 Amp (root3-2mm) 150-180 Amp (filler-4 mm)

80-100 Amp (root3 2mm)100-140 Amp (filler-4 mm)

80-100 Amp (MMAW Root)400-500 Amp (SAW Filler)

140-250 Amp

Welding current

Welding voltage

20-24V

20-22V

34-38V

20-29V

Pre Heat, Inter pass temperature, Post Heat Welding speed(mm/min) Heat input range (KJ/mm)

80° C (min), 250° C (max), 80° C (2 hrs min.)

20° C (min), 150° C (max), -

80° C (min), 250° C (max), 80° C (2 hrs min.)

- 150° C (max) -

110-150 1.2-1.4

70-170

400-600 2.2-2.5

60-100 1.5-1.8

1.6-2

Table 2. Joint parameters for double ‘V’ joint (S=40 mm)

Joint parameters

Value (mm)

6 +3

q (reinforcement height)

-1

54 +5

l (reinforcement width)

-3

4 +2

b (root gap)

-1

Fig. 1.Joint configuration for butt weld

2.3. Sample Extraction Plan

A test plan was first drawn for the purpose of evaluation of the properties of the weld coupons made by different welding processes. To meet the requirement as per the test plan, a sample extraction plan of test specimens from the weld coupon was done as shown in table 3. The tensile and impact specimens were drawn from either of the V groove, so that both sides of the weld were evaluated.

Table 3. Number of Specimen extracted from the weld coupons Sr. No. Test

Number of specimen

1 2 3 4 5

All weld tensile (round) Charpy impact specimen Chemical Composition

2 (either groove)

20 (either groove ); 3 samples x 6/7 temperatures

1

Metallography

1 (transverse section)

Hardness

1(transverse section – along three lines, either face and root)