Dymitr Petrow-Ganew, Herrenknecht AG

The Faculty of Mechanical Engineering of the Technical University of Lodz graduate. Polish trenchless technology precursor. Since 1993, the promoter of HDD method. He organized the first seminars and workshops concerning HDD in Poland (1996-1999). Since 2003 he has been working for the German company Herrenknecht AG. He introduced, among the others, many TBM machines to Polish market, e.g. for metro tunnel construction. He authored the several publications and papers on microtunnelling and TBM shields.
He is a member of the international organizations ISTT, ITA AITES and a member of Underground Construction Subcommittee of the Polish Committee of Geotechnics.

Direct Pipe for small diameters. Comparison of Direct Pipe, HDD and microtunneling technologies

The Direct Pipe technology for small diameters has been developed for crossing terrain obstacles with steel pipelines from DN500 to DN800 in the distance up to 1000 metres. Until now, the limitations in the use of smaller diameters in the traditional Direct Pipe technology were caused by the dimensions of the centrifugal pumps for the mud transport system, which were installed in the pipelines as well as the size of the hydraulic aggregate for the drive of the cutting head of the head. Along with the development and testing of the jet pump and compact hydraulic unit, the Direct Pipe technology has been able to perform pipe crossings with diameters from 20 “(508 millimetres) to 28” (711 millimetres) for distances up to 1000 metres. In the second part of the presentation, the following technologies will be compared: Direct Pipe, HDD and microtunnelling together with an indication of their advantages and limitations, especially in the installation of gas pipelines.