Trenchless method

Primus Line® is a trenchless rehabilitation of pressure pipes. That means: No more construction pits that are hundreds of feet or several miles long.

Two pits or existing chambers are absolutely sufficient for the rehabilitation of pressure pipelines. Learn here how a trenchless rehabilitation works with Primus Line®.


Establishing access

Small construction pits or existing chambers: That is all the space necessary for the installation of Primus Line®. Only two are required for every rehabilitation section. If necessary – junctions for example – additional pits are possible.

Rope winches are placed at the start and end pit for further work steps.

Shutdown of the pipeline

Before the rehabilitation can begin the pipeline has to be shut down according to relevant rules and standards. It is at the discretion of the operator whether or not to establish a provisional supply.

Inspection of the host pipe

Tuberculation is common in old pipelines. A clear picture of the condition of the rehabilitation section is very important for a successful installation of Primus Line®.

Visual inspection systems with high-resolution cameras and a large range of motion provide detailed recordings of the inside of the pipe, which are essential for efficient and productive pipe cleaning. They also pull through a pilot rope for the winches placed at start and end pit.

Cleaning of the host pipe

Proven mechanical procedures with spring steel scrapers and rubber discs reliably clean the pipe from encrusted deposits and loose debris - checked by a second camera inspection.

A free inner diameter is necessary for the installation of the liner.


Installation of the liner

Assembly of the pulling head

Before installation, the liner is fitted with a pulling head that is designed for forces of up to 22480 lbf. A swivel is utilized in the pulling process with the winch to prevent the liner from twisting on its way from start to end pit.


The liner is delivered folded. Primus Line® can be installed even in pipes with the same nominal diameter.

Adhesive tape keeps the liner in this U-shape until it is pressurized with about 7.25 psi. Subsequently, it assumes its round form.

Assembly of the connectors

Assembly of the M-Connector

The M-Connectors by Primus Line consist of a bushing and a core. With the M-Connector a pull-proof unit is established by hydraulically pressing the core into the bushing.

Screwed to a flange on the host pipe, a leak-free, pull-proof connection between is established.

Assembly of the R-Connector

The R-Connectors by Primus Line consist of a core and a bushing.

With the R-Connectors the core is first fitted into the bushing with an anti-friction agent. The bushing has a malleable steel jacket inside that is pushed onto the liner and into an indentation on the core by a two-component resin. The result is a pull-proof unit of liner and connector.

A leak-free pull-proof connection with the host pipe can be established with a flange or welding solution.

Pressure test

The pressure test according to relevant rules and standards for fluid and gaseous media ensures stability and leak-tightness of the section rehabilitated with Primus Line®. Specifically for water applications the liner is also disinfected.

Reintegration of the rehabilitated pipeline

Integration of a fitting piece

In order for the line to be properly recommissioned a fitting, or spool piece, is installed to reconnect the rehabilitated section with the pressure pipeline network.

Comprehensive documentation

The entire installation is accompanied by detailed documentation – from inspection to pressure test.

Your product watchlist