Question

In arc welding of a butt joint, the welding space is to be selected such that highest cooling is achieved. Melting efficiency and heat trnas efficiency aare $0.5$ and $0.7$, respectively. The area of the weld cross section is $5m{m}^2$ and the energy required to melt the metal is $10J/mm$. If the welding power is $2kW,$ the welding space in $mm/s$ is closest to

• A. $4$
• B. $24$
• C. $14$
• D. $34$

Answer 1

The correct option is C $14$

$\text{Let the welding speed is}Vmm//s$

$\text{Volume of weld/sec}=5Vm{m}^3/s$

$\left(5V\right)\times 10=2000\times 0.5\times 0.7$

$\Rightarrow V=\frac{700}{50}=14mm/s$