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The arrow on the body indicates the recommended pressure direction of the valve, not the direction of medium flow.Valves with a two-way seal can be either unmarked or marked with an arrow, as the valve arrow indicates the recommended direction of pressure, left or right or up or down, one of which is always better.

The arrow direction marked on the valve body indicates the pressure direction of the valve, which is usually marked by the engineering installation company as the medium flow direction, resulting in leakage or even pipeline accidents due to incorrect installation.

Pressure direction refers to the valve used in the closed state of the pipeline working condition, the arrow direction of the valve body is recommended to bear the pressure, if the wrong installation, the valve may be closed lax leakage failure phenomenon.Super soft seal ball valve is usually bidirectional sealing, usually not marked arrow, metal hard seal ball valve can achieve bidirectional sealing, but there will be a direction of sealing performance or a little better, so there will be marked arrow, this is to recommend the direction of the valve pressure, you can first consult the customer's opinion.

Hard seal butterfly valve with marked with arrows in different position of the pipeline, the direction of the arrow flow are not the same with the media, such as water pump in the pump outlet ends, the body of the arrow to the flow direction of medium and is on the contrary, as in the water pump into the water, with the medium flow arrow is consistent, such as the installation in the head of the road, the flow direction of medium arrow general adaptation, etc., depending on working condition and the installation location.