MagnaDrive Upgrades Water/Wastewater Applications

Improving operational efficiency while minimizing costs is paramount when it comes to water and wastewater applications.  The components used in these applications face strict regulations, aging infrastructure, and in many cases high-energy consumption.

MagnaDrive offered couplings to replace an entire belt system for the first example and adjustable speed drives (ASDs) for pumps in two other applications. The solution for all three examples led to lower maintenance costs, significant energy savings and numerous system efficiency gains.


City of Eugene, Oregon

The City of Eugene Wastewater Department efficiently and cost effectively treat wastewater for the Eugene-Springfield community to protect public health and the environment. They work together responsibly and safely, use innovative processes and advanced technology, and abide by all legal requirements.

When the lateral forces of the belt drive on the gearbox shaft created an unbalanced load – this created a maintenance headache and cost the City of Eugene approximately $10,000 per year in repairs.

MagnaDrive proposed the installation of a MGD 18/250 coupling to replace the entire belt system. The proposal was accepted and the coupling installed. MagnaDrive’s advanced cushioned start and stop coupling family has all of the benefits of the standard couplings with additional capabilities such as the ability to delay full torque transfer, partial disengagement to protect equipment, vertical and horizontal installation, and more.

The City of Eugene completely eliminated the $10,000 maintenance costs related to the belt system thanks to the MagnaDrive coupling installation. In addition, the City also realized a 35% ($34,800) energy savings, as energy was no longer being wasted as part of the belt loading.

The City’s project engineer, Gregory Watkins, said “…when we looked at the total cost of ownership over the life of the system, it was definitely the right decision.”


D.C. Water and Sewer Authority

The District of Columbia Water and Sewer Authority provides retail water and wastewater services to District customers as well as wholesale wastewater treatment to portions of Maryland and Virginia.

When a pump check valve failed, the resulting reverse flow back into the pump caused the pump shaft to break. Poplar Point rented different pumps to try to solve the situation (at $80,000 per month).

MagnaDrive’s Maryland/Washington D.C. partner, Das Solutions, proposed installing two (2) 26.5 Vertical ASDs with non-reverse clutches to prevent the pump shaft from rotating backwards and allow DC Water the speed control they required.

The MagnaDrive ASD is available in sizes ranging from 5 to 4,000 horsepower and speeds up to 3,600 rpm. Lower maintenance and operating costs are a result of transferring torque from motors to driven equipment across an air gap without shaft-to-shaft physical connection. This “disconnected connection” provides reduced vibration that increases bearing and seal life.

These ASDs were installed in 2011. At a 2013 meeting at DC Water’s main office, MagnaDrive was informed that the pumping station had saved almost 2 million dollars since the drives were installed. DC Water not only achieved the speed control they required, but were also able to remove the $80,000-per-month rental pumps.


Fairfax County Water, Virginia

Fairfax Water aspires to remain a respected industry leader, upholding its customers’ trust by providing water of exceptional quality and reliability, at a reasonable price, while supporting the high quality of life and economic vitality of the region.

With an oversized motor and only a control valve to control flow, the County wanted finer pump control through either a VFD or a MagnaDrive ASD (allowing them to adapt the pumping system as needed to demand).  As this is a 2,300 V application, the VFD was quoted at $100,000, a figure at which the County balked.

Fairfax Water installed a 24.5 Rigid Pedestal Adjustable Speed Drive on the pump in 2014. The ASD was 50% less expensive than the VFD option. After the ASD was installed, the pump station’s efficiency increased by over 50% (see chart below).


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