Clearing a blocked drain is really only the first part of a process. While a blocked drain is the most obvious sign that there is a problem with the way waste water drains away, it is actually only the conclusion of what might in many cases be a longer process.
Having cleared the blockage, a good drainage company will then try and identify the root cause. In many case, drains eventually become blocked because they are soiled or scaled. Descaling is called for in these instances as this will help prevent further blockages from coming about.
Professionals will generally make use of electro-mechanical equipment to descale sections of pipe. This will remove deposits and grease build-up as well as smoothing rough edges which can ultimately lead to much larger problems.
The machine used is in the form of a rotating drum filled with cable on which there is a cutting head suitable for the diameter of the pipe. The cable is fed through the pipe and scrapes away debris, smoothing the interior.
After this, scale is pushed through to an access chamber where it can more easily be removed.