What type of pump is a CVP?
Concrete volute pumps, Rodelta type CVP, are pumps that are integrated in civil constructions of pumping stations and are used for applications with a high flow rates while delivering low to medium heads. The combination of steel fabricated rotor units in volutes constructed in concrete makes it possible to pump more cubic meter of liquid with less pump installations. At the same time ensuring higher reliability and efficiency.
By minimising the number of pumps, the overall civil dimensions of the pumping station can be reduced. As a result less handling, less installation and less maintenance costs. All these aspects have a positive effect to the life cycle cost (LCC) and total cost of ownership (TCO).
Furthermore, the installed efficiency of thr CVP is higher compared to commonly used conventional Vertical Turbine Pumps (VTP) which are still the default design in this type of applications. The VTP selection often confirms the bowl efficiency instead of pump efficiency and therefore neglects the losses of the pump itself. The higher pump efficiency of the CVP is the result of the formed suction intake and not have the losses of the VTP riser column and discharge bend losses.
Rodelta can help in design aspects for an optimal solution.
Rodelta engineering capabilities can customize the sophisticated design of the CVP to meet customer preferences and the project required operating conditions. We strongly recommend to start these discussions at the earlier stage of the project. Changing specifications at a later stage may lead to significant impact considering engineering works and/or permits.
The choice of a specific speed of the pump influences the pump speed, it’s size and it’s performance parameters where lower specific speeds have lower rotational speeds, larger impeller diameters. At the same time lower specific speeds are less sensitive to cavitation and have less power required at shut-off pumping conditions. In case of higher specific speed pumps, a shut-off power higher than the rated power may have an impact on the required power rating of the electric motor and the accompanying electrical network.
One of the most challenging topics for these type of projects are the flow conditions in relation to the system resistance. The flexibility to work with different flows during lower and higher demands is often calculated considering the wrong system resistance, this result is wrong duty points and this leads to wrong selection of the pumps. When we can have a discussion on the required output of a station, Rodelta can be the second pair of eyes to look at optimums on size and quantity of pumps. Furthermore we can present a script on timing to start-up and shut-off of pumps during different modes of operation.
For more information regarding advantages of Concrete Volute Pump (CVP) compared to a Vertical Turbine Pump (VTP). Press here.
P.S.
There are several execution forms of Concrete Volute Pumps see also ACVPSCVP and CVP.
Rodelta also has the knowledge and expertise to design these pumps in a fish-friendly execution. More information can be found here.
For project example fish-friendly concrete volute pump execution see pumping station Orveltesluis.
