经碲变质处理的铝硅合金是制造高气密性铸件的理想材料。
After a new installation or maintenance for hydrogen system, pressure test, flushing and gastight test must be done.新安装或大修后的氢气系统必须做耐压试验、清洗和气密性试验,符合有关的检验要求,才能投入使用。
Recirculation fumigation equipment was used to ventilation after the warehouse was rebuilt in gastight and heat insulated.将仓房进行气密和隔热改造后,利用环流熏蒸设备,进行环流通风。