A pipeline constructor asked to check and validate the design of PU spacers protecting a 3LPE (3-layer polyethylene) coating during the pulling of a pipeline section through a concrete tunnel. Furthermore, the section needed to pass the hydrotest.
First, the force profile needed to pull the section through the tunnel was calculated. Then, a detailed simulation of the total load distribution within and outside one spacer during pulling and hydrotest was made.
Finally, the introduction into the tunnel was simulated for the first spacers.
As the calculated stress within all spacers remains below acceptable treshold during pulling and hydrotest, the spacer design was validated.
No problems accurred during the installation of the pipeline through the tunnel.
With the courtesy of EUPEC
Detail of in field applied spacer
Finite element modelling of stress during hydrotest
Finite element modelling of minimum principle stress during pulling
Installation of pipe with spacers
Preparing the pipe laying
Overview of spacers on pipe