灰口铸铁管件
Gray iron castigs for pipe fittings
稀土灰口铸铁
rare earth grey cast iron
稀土灰口铸铁高压暖气片
radiator of rare-earth grey cast iron
灰铸铁管和配件
grey iron pipe and fitting
灰铸铁金相
Gray cast iron metallography
灰铸铁气焊
Flame welding of gray cast iron
灰铸铁缸套
gray cast iron cylinder liner