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铸铁管是与国计民生密切相关的重要产品,一个国家铸铁管的人均占有量是一个国家生产和生活水平高低的重要标志之一。
Cast iron pipe is an important product closely related to national economy and people’s livelihood. The per capita possession of a country’s cast iron pipe is one of the important symbols of a country’s production and living standards.