GRUNDOMAT N from the TT Group hits the market

Mar 07, 2012

The new GRUNDOMAT N soil displacement hammer generation is a milestone in the 40 year success story of GRUNDOMAT. The new generation now improves the propulsion and directional stability for an even greater target precise installation. The new GRUNDOMAT N sizes will be available in diameters 45 – 55 – 65 – 75 – 85 – 95 – 110 – 130 – 145 – 180mm.

The TT Group announce that the previous generation (P-Version) will still remain in the sales programme. Also the N-Version will be offered at the same price as the P-Version until further notice.
A distinct characteristic of the GRUNDOMAT-N is certainly the crowned head, which expands the bore hole to the full bore diameter. The sharp cutting crowns force themselves into larger stones to pulverise and split them. With the small pointed attack surfaces on the cutting crowns the largest possible effective striking energy is achieved. The broken ground material displaced passes through the openings and is conveyed to the rear of the head. Then the forward penetration process begins. The moving „head work“ is therefore carried out in four distinctive working steps instead of three as per the P version:
  • Advanced impact strike
  • pulverisation
  • conveyance
  • penetration
The crowned head extends the application spectrum for soil displacement hammers in soils, where a high cutting efficiency is vital, but the head profile can also be exchanged, if necessary, for a P-Generation stepped head, without any problem whatsoever.
Furthermore the GRUNDOMAT N has a triple gear control stud. The impact striking frequency is chosen via the 2 forward gears. Therefore it is easier to adapt boring speeds to various soil conditions and provides a smooth and constant propulsion, particularly useful for a low impact start during the alignment and launch process. The GRUNDOMAT N can be switched into reverse gear in a similar way to the P version.
HDPE or PVC pipes are either installed immediately or after boring with the GRUNDOMAT. The pulling cable required for this is equipped with a steel cable insulator. Together with a high quality non conductive compressed air hose, providing improved safety protection for the operator is guaranteed.
The GRUNDOMAT N is also service friendly. If, for example, a seal ring has to be exchanged, or a pull sleeve assembled, then the conversion can be carried out on site. There is no need for any heating or adhesive on the threaded connections, so no hardening times necessary. The trick: A tensioning element spreads the threads like a dowel and this way it fastens the casing end into the main casing. As with all GRUNDOMATS the cutting head and piston have been hardened and the casing has been chrome plated on the inside and outside. The main piston moves on slide rings which prevents any metal to metal friction between the sliding piston and the GRUNDOMAT casing. Seal rings keep the air consumption to a minimum. All this leads to low maintenance expenditure and a long service life.
The GRUNDOMAT is used for under road and railway track crossings. HDPE and PVC pipes up to ND 160 can be installed. The short GRUNDOMAT types 65, 75 and 95 NK are preferred for house connections with shorter installation lengths and tight working areas. The shortest hammer, Type 65 NK only has a length of 930 mm and is therefore approximately 10 cm shorter than the previous model Type 65 PK. The soil displacement hammers are increasingly being started out of buildings and then cross under the gardens surrounding the houses, up to the mains connection.

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TT UK Ltd.

10 Windsor Road

MK42 9SU Bedford

United Kingdom


+44 1234 342566


+44 1234 352184



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