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Innovative Pipe Repair Technique Saves Time , Money
March 2017
As KICA continues its drainage replacement / repair work on the island , currently working on areas around Cougar Point Golf Course while it is closed for renovations , they recently encountered a unique situation .
" Most of our drainage pipe repairs are done via a method called spin casting ," said KICA Maintenance Director Will Connor . " This method , however , only works for larger pipes , so when we encountered a smaller pipe at Cougar Point Hole 9 in need of repairs , we had to look at alternate solutions ."
Searching for the most efficient and effective way to repair the pipe , Will and his engineering team turned to a method called Curing in Place ( CIPP ).
" CIPP does not require manned entry and allows us to repair a pipe in place without digging the pipe up and replacing it ," explained Will . " In many cases , digging up a pipe leads to more disruption , greater damage and higher costs , all of which we wanted to avoid if possible ."
CIPP is a multi-step process . First the area around the pipe is dewatered , in KICA ' s case , using large rubber bladders . The bladders are placed strategically on the water surface and then pumped full of water from the pond . As the bladder fills , it sinks and grows larger , effectively damming the pond . Then the remaining water is pumped over the bladder and out of the area to be dewatered . The pipe to be cured is then cleaned with pumps and a vacuum truck .
Next , a liner is manufactured off site at the correct diameter and length . The liner , which according to Will looks " like a long sock ," has a resin to adhere to the inside of the pipe that will also harden . To insert the liner , scaffolding is brought in to allow the liner to be elevated approximately 13 ' above the end of the pipe . According to Will , the 13 ' is important because water will be pumped into the liner and the hydrostatic pressure ( sometimes referred to as ' head ') will force the liner through the pipe . As the liner is pushed through , it inverts so the resin is now contacting the inside of the pipe , and the head pushes the resin firmly into place .
Finally , after the liner is in place , the water is pumped out . The ends of the liner are secured , and then low pressure steam is pumped into the pipe . The temperature inside the pipe is elevated to about 180 degrees and stays in that condition for several hours . The heat causes the resin to activate and harden , and becomes essentially a new PVC pipe within the old damaged pipe .
This method provides a cost effective and time efficient way to handle repairs on these smaller pipes , while ensuring that the repairs are durable and reliable in the long-term .
For more information on this and other island projects , visit kica . us / projects .