down draft

The technological characteristics of upward horizontal cut and fill stoping,mechanized upward drift cut and fill method and mechanized downward drift cut and fill method are introduced and a few points to improve them are put forward.

介绍了焦家金矿先后试验应用的上向水平分层充填采矿法、机械化上向进路分层充填采矿法及机械化下向进路分层充填采矿法的工艺特点，并提出了几点改进意见。

Analysis of heating line weld defects by down weld with fibrin electrode;

供热管道纤维素焊条下向焊焊接技术分析

Introduced here is the advanced flux cored down weld technology.

介绍了药芯焊丝自保护下向焊技术。

Application of technology of metal pipe full-position downward welding in a construction;

金属管道全位置下向焊技术在某工程中的应用

The article analyzed the feature of downward welding technology and the special demand for arc welding machine.

就管道焊接中的高效焊工艺方法———管道下向焊的工艺特点及对弧焊机的特殊要求进行了剖析，介绍了适用该工艺方法的几种品牌焊机，对工程施工单位及焊机制造厂商具有一定参考价值。

It also presents the application of downward welding method and craft in the practice and caution.

对中国第一汽车集团公司供热管网工程进行介绍,对长距离大管径金属管道焊接中的高效焊接工艺方法进行简要综述,介绍了管道下向焊施工方法及工艺在工程实际中的应用及注意事项,对下向焊施工方法及工艺进行了推广。

Experimental study on new downward drift mining technology with backfilling by high water content materials;

下向进路高水充填采矿工艺试验研究