这大大缩短了一炉钢的冶炼时间。

This resulted in greatly reducing the time of a single heat.

钢厂必须对每一炉钢进行熔炼分析.

An heat analysis of each heat of steel shall be made by steel manufacturer.

转炉大补炉后冶炼第一炉钢时钢中磷含量容易偏高，有时甚至超出钢种要求的磷含量上限。

The phosphorus content in the first heat steel of converter steelmaking after fettling was higher than normal operation and some times even higher than the standard limitation.