In general, the diameter of the spiral steel pipe tube can be divided into outer diameter, inner diameter, nominal diameter. Pipe material for the spiral steel pipe pipe outside diameter with the letter D to indicate, followed by additional outer diameter of the size and wall thickness, for example, the outer diameter of 108 seamless steel pipe, wall thickness of 5MM, with D108 * 5, said the plastic pipe is also expressed in terms of the outer diameter, such as De63, others, such as reinforced concrete pipe, cast iron pipe, galvanized pipe and so on, using DN, in the design drawings are generally used to indicate the nominal diameter, nominal diameter is In order to design, manufacture and maintenance of the convenience of artificially stipulated a standard, but also more nominal diameter, is the name of the specifications of the pipe (or fittings).
The nominal diameter of the tube and its inner diameter, outer diameter are not equal, for example: nominal diameter of 100MM spiral steel pipe post 102 * 5, 108 * 5 and so on several kinds of, 108 for the tube's outer diameter, 5 said the tube's wall thickness, so the tube's inner diameter (108 * 5-5) = 98MM, but it is not exactly equal to the tube's outer diameter minus two times the difference between the wall thickness, it can also be said that nominal diameter is close to the inner diameter, but not equal to the inner diameter, but also not equal to the pipe. In the inner diameter, but is not equal to the inner diameter of a pipe diameter specification name, in the design drawings, so use the nominal diameter, in order to determine the nominal diameter according to the pipe, fittings, valves, flanges, gaskets and other structural dimensions and connection dimensions, the nominal diameter of the symbol DN, if the design drawings using the outer diameter, should also be made to compare the table of specifications for the pipe, indicating that some kind of pipeline nominal Diameter, wall thickness.
How to realize energy saving of spiral steel pipe for conveying fluid Conveying fluid pipe seizes the seasonal change of lower temperature in late autumn, and adopts the working measures of reasonably starting and stopping the running fan of the cooling tower and the axial fan used for cooling in the pump room to reduce the electricity consumption effectively. According to the professional management department estimates, only this one, you can reduce the cost of nearly 100,000 yuan per month. In the daily production operation of 15 sets (sets) cooling tower fan running at the same time full load, the total power up to 1600kW per hour, is a real power user. Due to the steelmaking system, continuous casting system on the supply of water media have special requirements, especially when smelting fine steel, water media temperature control plays a crucial role in stabilizing product quality and the development of new steel.
In addition, it can also utilize the change of outdoor temperature to start and stop the fan reasonably, so as to achieve the purpose of reducing power consumption and saving energy. Take the initiative to contact with each production line user point, in-depth understanding of the specific requirements of the water temperature, to determine the most reasonable range, in order to meet the production needs at the same time, to achieve the purpose of reducing costs and increasing efficiency. Make full use of the characteristics of seasonal changes and lower outdoor temperature at night, adopt the method of real-time tracking and detecting the water medium temperature change data transmitted by the staff on duty at the production site, make timely adjustments to the running fan, and minimize the number of running fans. Since one week, the number of running fans has been reduced by half, and the power consumption has also been reduced by half.
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