Spiral pipe is generally sent to the hands of the user production workshop is not put so much spot, which requires the dealer to place some spot. However, dealers generally do not have a large indoor warehouse, most of them are outdoor warehouses, spiral pipe in the outdoor put can not avoid the wind and sun. So, how to distinguish between floating rust and rust of spiral pipe?
The so-called floating rust, as the name suggests, is floating to the spiral pipe above a layer of rust, with a towel or something else can be removed, simply put, floating rust is also considered no rust, belongs to the normal state.
Spiral pipe rust is a long time, at least 1 year or more in the outdoor spiral pipe after the wind and sun, rust spiral pipe above the large and small pits, which is also a big difference between the spiral pipe floating rust and rust.
Spiral pipe is through the steel mill billet saw section, and then heated in the annular furnace - piercing - calibration - straightening - cooling - drama head - packing to become a qualified finished product, spiral pipe is mainly used for oil, natural gas transmission pipeline, its specifications with the outer diameter * wall thickness. Spiral pipe has single-side welding and double-side welding, welded pipe should ensure that the hydrostatic test, tensile strength of the weld and cold bending performance in accordance with the provisions.
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