Flexible polyurethane couplings

Couplings play a critical role in wastewater processing. In a wastewater facility in New York City Dura-Flex couplings resist high loads, harsh chemicals and UV radiation.

Waste water facilities face many tough operating conditions every day. Easily processing many hundreds of millions of gallons each day, they operate on a continuous cycle whilst being exposed to water, chemicals, high shock loads and extreme temperatures. Couplings play an important role in wastewater processing by controlling vibration, minimizing misalignment and reducing maintenance costs. While they should operate maintenance free for many years, poorly specified couplings can fail which leads to lengthy downtime.

A wastewater facility in New York City was regularly suffering premature failure of couplings; personnel had become resigned to the fact that this was unavoidable due to the heavy duty nature of the application. As well as the high loads and harsh chemicals that they are subjected to, couplings are exposed to UV radiation constantly throughout the day. The sunlight was causing the elastomeric flex element of the couplings to crack and peel, leading to unit failure.

The plant superintendant comments: "We had tried a number of different couplings in our final tanks; none of them could handle seasonal temperatures or UV exposure. After repeated failures with different products we just assumed that the nature of the application meant that the couplings would have a short operating life."

During a routine maintenance and repair inspection, an outside contractor was informed of the recurring coupling failures and was able to recommend TB Woods' Dura-Flex couplings. The Dura-Flex products employ a light-weight element that absorbs shock loading and torsional vibration; the flexible polyurethane material has been specially formulated to withstand the effects of UV radiation making it an ideal solution for applications that are situated outdoors. The material is highly resistant to chemicals and requires no lubrication which made it the idea long-life / low maintenance solution for the wastewater facility.

The plant superintendant continues: "Since we were recommended the Dura-Flex we haven't had a problem with unexpectedly short ware times and my maintenance staff is very pleased. Today we have more than 25 of the couplings operating 24/7 365 days a year. I now understand that it is critical in outdoor applications that require couplings to make the right choice.