The bottom side of the line plate shall be cleaned up (no oil stains), and all the screw holes on the plate shall be tapped with screw taps.

线条板底侧面清洁干净(不能有油污)，板上螺丝孔全部用丝攻攻牙一次。

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This is made from a part which is machined up on the lathe and tapped for screwing into the valve-plate, and a short section of steel tubing.

这是由一个是加工上的车床和到阀板拧挖掘的一部分，以及钢管短节。

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