氧乙炔焊

yǎng yǐ quē hàn

oxyacetylene welding

氧

yǎng

oxygen (chemistry)

乙

yǐ

second of the ten Heavenly Stems 十天干[shi2 tian1 gan1]

炔

quē

alkyne

焊

hàn

variant of 焊[han4]