Applus+ completes CIPP installation of a UV DN800 GRP liner for the first time in Qatar

Applus+ Velosi in Qatar’s CIPP lining team has recently installed a 59m 800mm diameter GRP liner at a project site in Doha, the first of its kind in Qatar, and the results were satisfactory to the client.

Cured-in-place pipe (CIPP) is one of several No-Dig or Trenchless rehabilitation methods used by Applus+ Velosi to repair existing pipelines minimising or eliminating the need for excavation. CIPP is a jointless, seamless pipe-within-a-pipe with the capability to rehabilitate pipes ranging in diameter from DN 100 to DN 1600. The process is carried out through the manholes, avoiding excavation and traffic congestion.

There are several different materials and methods of curing. Applus+ Velosi reinforces liners with glass and cures them using UV technology. The majority of pipes being rehabilitated with CIPP are sewer and drainage ducts, which tend to present internal failings and infiltration problems. 

During the installation in Qatar, there were many challenges, the main one being the amount of infiltration coming from a 45m longitudinal fracture at the inversion of the pipe. Applus+ Velosi and the client came up with an innovative solution to dewater the pipeline and lower the water table; this enabled us to install the liner in dry conditions. Once lined, these pipes are secure for up to 50 years.