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Removing False Myths Of Siphonic System

Hola, hoy voy a tratar de analizar y compartir con vosotros algunos de los “falsos mitos” asociados al sistema sifónico.


Hello, today I will try to discuss and share with you some of the "myths" associated with the siphonic system. For example, the discharge capacity of the system. It is true that a siphonic system drains flow 8 to 10 times faster than a traditional equivalent system. However this great potential is not fully utilised because for the same diameter a greater siphonic speed would mean to drain rain with a very high return period, more than 500 years. What is usually done is to set the intensity parameter first and then decide the system to use. If both siphonic and traditional systems are correctly calculated for the same intensity, then we can say that the discharge capacity of both is equivalent because the product section for speed, despite having different values for the factors, will offer the same flow. What is then the advantage of siphonic over traditional system? Manhole, the main advantage at maximum flow level (or protection level) is that the siphonic system can easily adapt to higher intensities without incurring in the use of large diameters. That is, when the roof of a building "put all its eggs" in the storms of high intensity and short duration, the siphonic system offers all the design possibilities while the traditional system reaches a maximum in which its pipes could, and indeed do, enter in load with the risk of collapse, plus the drainage saturation as the gravitational system is not designed for such rains and "it reaches its limit." Therefore, as a final summary, we must realise that to a certain rainfall intensity threshold both hydraulic systems function with equivalent performance, while in the case of high intensities the siphon can be designed for much higher intensities with advantage of protection for the building. Even clearer: It is the intensity parameter that matters, regardless of the type of system used... Even if you use the correct parameter, the superiority of the siphonic system is clear. Another major erroneous beliefs in my view is that of perceived cost. We tend to hear that siphonic systems are expensive but we do not try to make the comparison with the necessary rigor. It is essential to include in this comparative savings in civil works and interior manholes involved in the use of siphonic drainage. If this factor is taken into account we can see average savings of 30% which may be higher or lower depending on other factors, especially: Number of gutters or inland valleys, soil type, right rainfall in the area, etc. There is another factor that is not usually taken into account: the acceleration of the work planning. If coordination of the siphonic consignment is properly done (arriving just before or immediately after the roof safety nets) it can produce a stunning performance and total control of the risk of water ingress during the period of work. Time is also money, and having a workable soil in site is priceless as it will affect the rest of guilds in their productivity. Finally, it should be noted that after the introductory period of these systems in the past decade we have a very competitive price level.


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