Seal of Approval for new Compound

Story courtesy of the Water Corporation of WA.

After the driest winter on record for the metro area and with the public being asked to
do their part to stop Perth drying out, fixing leaks in our infrastructure quickly is more
important than ever. But how do you fix a leak when the pipeline can’t be shut down?
On our sluice valves, we’ve started using a sealant which can be injected while water is
still flowing through the system. It’s a compound of Teflon and organic oil, and has so far
been used for small and moderate leaks.
A small injection hole is first drilled, and then the sealant is injected at high pressure into
the ‘gland packing box’ of the valve using a hydraulic pump. The sealant flows around the
packing box and fills any gaps, which stops leaks.
Recently, a substantial leak was detected in a valve in Medina, and the pipeline could not
be shut down because of operational requirements. Excavation was arranged to gain
access to the valve, and with the pipeline still in service, the sealant was injected. This
completely stopped the leak and the valve remained useable.
There have been some challenges in introducing the sealant, including bringing in the
compound from the United States, gaining Department of Health approval to use it and
bringing a representative from our supplier in Brisbane to Perth to demonstrate it’s use.
The sealant has so far been used on 760mm water supply valves, but it has potential to
be used on larger valves and also wastewater valves in the future.
“The sealant provides a cost effective way to maintain our valves, which also means we
don’t have to shut them down,” says Supervising Engineer with our Water Production
Branch, Terry Willcocks. “Both Nathan Blight from Mechanical Services and Dave Hodson
from PSN Water have done a great job and worked together to make the sealant available
for maintenance of our valves.”

A representative from our supplier in Brisbane visited us to demonstrate the use of the sealant,
which is injected using a hydraulic pump.