Pressurized Return Piping Vs. Overhead Trench Filtra-Systems has the experience and expertise to design the optimum piping system to carry the coolant and chips from the pumpstations to the filter. Piping systems can be pressurized returns, gravity flow or a combination of both, depending upon the distance between the pumpstation and the filter and the critical carrying velocity for the chips. The picture shows six individual pipes from six pumpstations entering a gravity return header. The header then traveled three hundred feet across the plant and discharged into Filtra-Systems HV-12D Hydro-Vac central filtration system. This design was the most economical and efficient for a plant running seventy-two CNC machines, which were supported by one central filtration system. Put Filtra-Systems experience and expertise to work for your company when designing return piping systems and eliminate the cost, environmental liability and mist problems associated with in floor trench.