Hi All,
Just wondering if anyone is using pressure diffentials in their design of dual reticulation systems (ie maintain a higher pressure in the potable main than recycled main) so as to minimise risk of cross contamination in the event of accidental cross connections. Im referring to large...
Hi Stanier,
Ahh...so you had a PSV on the end of your main which basically prevented the main from emptying ie if the pressure starting dropping, the valve started to close and then it actually closes when the pump stops (or thereabouts). I guess you modelled this using a water hydraulic...
Hi Stanier,
Thanks again for your feedback. Wasnt really thinking about actually constructing the downhill portion with bolted manholes but only simulating the partial full situation by using fake bolted manholes. See the following and in particularly Tom Walskis notes...
Hi stanier,
Thanks for your response. Much appreciated. One other question. How would you design the pump head for such a system (assume the orginal scenario with no gooseneck, control valve etc). Would you assume the scenario where the pipe is fully pressurised (ie steady state equations). Or...
Hi all,
Ive got something very similar whereby i am pumping downhill from the high point (which is at the pumping station). There are intermediate high points along the way along with a river crossing.
The only time the force main will be running full will be during ultimate wet weather...
Thanks dicksewerat,
Ive modelled the force main and the MAX velocities are very low (ie < 1 fps !!) in large sections of the main. The model showed large attenuations of flows in the mains (ie the pump was pumping 600 l/s while some areas were as low as 100 l/s in the lower ends !!!). I...
Hi all,
We've got a sewer pumping station where the high point is at the station itself and then it pumps downhill with several intermediate high points, then goes under a creek to the recieving sewer on the other side. Air Valves will be placed at hight points. There will be large amounts of...
Hi all,
We've got a sewer pumping station where the high point is at the station itself and then it pumps downhill with several intermediate high points, then goes under a creek to the recieving sewer on the other side. Air Valves will be placed at hight points. There will be large amounts of...
Hi All,
If we have a water reservoir (say with a water level of 100m), then 2km of 300mm watermain to a pressure reducing valve, how is the 'maximum allowable pressure drop' across the valve calculated. Just to note that downstream of the Pressure Reducing Valve is a normal water reticulation...
Does anyone use (or know of) minimum velocity criteria when designing new potable water distribution systems to maintain water quality (ie water age).
Thanks in advance for any comments.
The valve is to be used for a water distribution network to reduce high system pressures downstream of the valve. "They" refers to the tech. specification of the valve produced by the designer.