ALC and public drainage十月 21, 2015
As ALC registered drainlayers we get to take part in some exciting drainage work. Public sewer and stormwater is what we love doing! BIG PIPE, BIG DIGGERS and BIG HOURS are involved. Experience is an absolute must as one minor mistake can cost the drainlayer tens of thousands of $$$ to put it right, and we don’t want that! The first and most important step is preparation. Understanding the scope clearly will enable us to plan the hours, place the correct quantities and have the right machinery onsite.
On this job for example a specialized manhole stormwater 360 filter weighing over 2.3 tonnes is to be installed. Additionally over 50 meters of concrete RCRRJ 225mm, each weighing over 100KG (2 meter) need to be installed at a perfect fall of 1%.
Not only is manpower important to deal with the size and weight of this application but also having professional specialized tools is critical. Just to give you an example…
Once the all the pipe is laid several tests will have to take place to enable us to pass council and engineering standards.
- The pipe will be air tested using an air compressor and balloon. The installation must prove to be “leak free”
- A tractor unit carrying a 360 rotating camera to inspect each joint to ensure the rubber rings have not been damaged during installation and that the gap between each pipe is as tight as possible. No cracks should ever be visible.
- Finally a visual inspection is done which must result in a “full moon”. Simply put, you look down the pipe and if the drainlayer did everything correctly then you should see a full moon (light) at the other end, indicating that the pipe is perfectly straight. You can imagine how difficult that would be if the trench was not excavated correctly to begin with. Especially when the depths are over 1 meter!