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Standard IX

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Spot welding ...

Question

Spot welding of two steel sheets each $2 m m$ thick is carried out successfully by passing $4 k A$ of current of $0.2$ seconds through the electrodes. The resulting weld nugget formed between the sheets is $5 m m$ in diameter. Assuming cylindrical shaper for the nugget, the thickness of the nugget is
2.91

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Solution

The correct option is A 2.91
$Given data:$

$t = 2 m m, I = 4 k A, Time = 0.2 s$

$D_{N} = 5 m m$

$I^{2} R t = Volume \times ρ \times H.R/kg$

$4000^{2} \times 200 \times 10^{- 6} \times 0.2 = V o l . \times 8000 \times 1400 \times 10^{3}$

$h = 2.91 m m$

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Spot welding of two steel sheets each 2mm thick is carried out successfully by passing 4kA of current of 0.2 seconds through the electrodes. The resulting weld nugget formed between the sheets is 5mm in diameter. Assuming cylindrical shaper for the nugget, the thickness of the nugget is 2.91

The correct option is A 2.91Given data: t=2mm,I=4kA,Time=0.2s DN=5mm I2Rt=Volume×ρ×H.R/kg 40002×200×10−6×0.2=Vol.×8000×1400×103 h=2.91mm

The correct option is A 2.91
$Given data:$

$t = 2 m m, I = 4 k A, Time = 0.2 s$

$D_{N} = 5 m m$

$I^{2} R t = Volume \times ρ \times H.R/kg$

$4000^{2} \times 200 \times 10^{- 6} \times 0.2 = V o l . \times 8000 \times 1400 \times 10^{3}$

$h = 2.91 m m$