This article gives a brief description of a special tool for assembling and disassembling of seal rings in the wedge-shaped gate valve for oil (gas) well-head assembly.

本文简要地介绍了装拆采油(气)井口楔形闸密封圈的一种专用工具。

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Senior leaders including Vice-President Nicolas Maduro, the head of the National Assembly Diosdado Cabello, and Oil Minister Rafael Ramirez have been travelling to and from Cuba in recent weeks.

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