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As far as I can see there is no reason why you need to have a valve on the end of the pipeline discharging into the receiving reservoir tank. What would be its purpose in any case? It would be a liability. Even if the delivery pipe (and joints & fittings) could withstand the static head when closed there could be other problems of water hammer if it was possible to close the valve quickly (unlikely if a screw down gate valve but something to avoid). Ensure the valve is on the entry to the delivery pipe so that the flow can be diverted to the spring or a break pressure overflow. This gives the opportunity for maintenance on the delivery pipe and fittings when necessary.

Re: Point 2, I’m not sure why the pipe cannot freely discharge into the tank, above the tank, so that there is no possibility of a head of water building in the tank to provide any resistance to flow. The overflow would have to be sized sufficiently to ensure the tank does not fill to overflowing so that flooding and erosion around the base of the tank is prevented. So, in both scenarios (piped directly into the tank or discharging above the tank) the overflow needs to be large enough to discharge at a rate matching or exceeding any incoming flow.

As regards break pressure “tanks”, they do not have to be purpose built tanks, as such. If space is a premium or there are construction difficulties then it is possible to place the delivery pipe inside a larger diameter receiving pipe (even if it is eventually reduced down to the same diameter) so that the pressure is “broken” to atmosphere. However, you may find the system overflowing at this point depending on the flow in each pipe section. But this design is an alternative to constructed “tanks”.

Regards,

Jan Davies

As far as I can see there is no reason why you need to have a valve on the end of the pipeline discharging into the receiving reservoir tank. What would be its purpose in any case? It would be a liability. Even if the delivery pipe (and joints & fittings) could withstand the static head when closed there could be other problems of water hammer if it was possible to close the valve quickly (unlikely if a screw down gate valve but something to avoid). Ensure the valve is on the entry to the delivery pipe so that the flow can be diverted to the spring or a break pressure overflow. This gives the opportunity for maintenance on the delivery pipe and fittings when necessary.

Re: Point 2, I’m not sure why the pipe cannot freely discharge into the tank, above the tank, so that there is no possibility of a head of water building in the tank to provide any resistance to flow. The overflow would have to be sized sufficiently to ensure the tank does not fill to overflowing so that flooding and erosion around the base of the tank is prevented. So, in both scenarios (piped directly into the tank or discharging above the tank) the overflow needs to be large enough to discharge at a rate matching or exceeding any incoming flow.

As regards break pressure “tanks”, they do not have to be purpose built tanks, as such. If space is a premium or there are construction difficulties then it is possible to place the delivery pipe inside a larger diameter receiving pipe (even if it is eventually reduced down to the same diameter) so that the pressure is “broken” to atmosphere. However, you may find the system overflowing at this point depending on the flow in each pipe section. But this design is an alternative to constructed “tanks”.

Regards,

Jan Davies