He welded the pieces of metal together using oxyacetylene .

他用氧乙炔把金属片焊在一块。

The most common form of welding is oxyacetylene .

焊接的形式最多见的是氧电石气。

Nickel was even harder ; he cheated and bought some commemorative coins , melting them with an oxyacetylene torch .

镍更难获得；他以哄骗加购买的方式，得到了几枚纪念币，用一支氧乙炔焊炬把它们熔化。