R409 + pipeline trench through the roof and installation of roof rain.

R 409 +管道穿屋面及地沟顶板防雨装置。

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How to make the backfilled soil of pipeline trench stabilized in an effective manner is a major concern for the normal operation of pipeline.

如何采取有效的手段保持管沟回填土，是涉及管道正常运营的大问题。

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Beijing Fuxing the pipeline Equipment co., Ltd. is a professional production and sale of the pipe trench integrated companies.

北京金福星管道设备有限公司是一家专业生产、销售沟槽管件的综合性公司。

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