centrifugal pump pipe network as an example, what kind of link is recommended with the meaning of it, on a more general view is to content relevance as the basis. If so, it must be Links pipeline centrifugal pump centrifugal pump or other sites, the so-called self suction pump, sewage pump should not related? You will say, this nature is counted, all pumps website! So, I have to ask if this is so, the website is not related to the valve, pumps and valves are always very similar, perhaps you still said to be. Well, so be it, I ask, what if the terminal machine, CNC machine tools machinery station is not related to these, this time you may hesitate, but I believe that most people would still say, because they are the machinery station.