With the Wilo-Axum Pro the pump manufacturer presented an easy way to find a secure solution for pressure drainage systems at this year’s ISH.
Once the most critical pump has been configured, a smooth process is guaranteed throughout the system. The pump generates an enormous pressure that can master any bend or obstacle without difficulty. Wilo-Axum Pro can be used to its full effect when combined with the Wilo-RexaLift sump because both were specifically developed for pressure drainage of domestic sewage. The two sewage professionals from Wilo work completely reliably and provide first-class results, even if changes have to be made because of building works, or if deposits build up or air becomes trapped in the pressure pipe. The all-round care-free package for planners and operators.
Large volumes at high pressures
Wilo-Axum Pro combines the benefits of various hydraulic principles: the pump moves a large volume (for displacement pumps) at a high pressure. It can therefore be used in lines of up to DN 50 and it reliably generates a flow rate of at least 0.7 m/s in any pipe diameter, which can otherwise only be achieved using centrifugal pumps. The new pump can meet both requirements – volume and pressure – simultaneously. As a result, the pipes can be designed to be low-loss and energy efficient. Even if there are numerous shifts between highs and lows along the line, the pump system will always run perfectly safe.
Low wattage reduces costs
The centrepiece of the system, the Wilo-Axum Pro pump, has outstandingly efficient high-pressure hydraulics. According to the manufacturer no other progressive cavity pump for pressure drainage available today has a better delivery rate. Whereas centrifugal pumps need a rated motor power of up to 6.6 kW to achieve the same delivery head, the Wilo product requires just 1.8 kW. This is an advantage that planners and investors can benefit from: instead of the – often expensive – switchgear with delta-wye transformers that is compulsory from 4 kW, it is possible (with a maximum head of 60 metres) to use significantly more economical switchgear for pumps with direct starting (DOL). This reduces loads on the electric grid and reduces investment costs considerably. Wilo-Axum Pro combines power and control: the hydraulic system is self-regulating between 1 and 60 metres. It automatically throttles the hydraulics to a pressure no higher than 10 bar so there is no risk of damage to the piping. If it temporarily exceeds the maximum permissible pump curve of 6 bar when demand is high, the motor s sensors detect the resultant heat and switch the pump off. No further safety features, such as pressure-relief valves and burst mechanisms to protect the pipes, are necessary, unlike with other displacement pumps.
Minimised pressure chamber prevents obstructions
The rotor is made of stainless steel, the stator is made of oil-resistant nitrile rubber (NBR). Wilo-Axum Pro counters the specific challenges of conveying sewage and its high solid content with an external macerator that breaks up the floating material into a manageable size. In addition, it swirls the solid material in the sump, thereby preventing it from settling or forming a floating layer. The volume of the pressure chamber has been kept to a minimum so that only minor quantities of dirt particles can settle when the pump is at a standstill. This is particularly important given that the quiet-running, long-lasting four-pole motor ensures maximum lifetimes for the rotating parts. When the pump starts up again, the small deposits inside the hydraulics are removed immediately. As a result, Wilo-Axum Pro prevents clogging. This is achieved by the high pressure that the pump can create at large conveying volumes and with low energy consumption, thanks to its advanced technology.
Reliable in every detail
Wilo-Axum Pro and Wilo-RexaLift combine to make a powerful team that can master almost any pressure pipe situation. They are reliable in every detail: protected mechanical seals ensure maximum safety for the electrical components. From dimensioning through to maintenance, the system is easy to handle – due to the removable non-return ball valve, the stop valve in the sump that can be operated externally and the pump s sealing chamber, which is accessible from outside and has optional monitoring. The explosion-protected design with a longitudinally watertight, cast but disconnectable cable is yet another feature available as standard.
Picture: Wilo-Axum Pro is an effective solution for pressure drainage systems. It manages large volume flows at high pressures, continuously regulating itself hydraulically to below 10 bar, protecting the entire pipe system from damage. (Image: Wilo)