NAV

NAVIGATIONAL DRILLING SYSTEM

2006.0660.06

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NAVIGATIONAL DRILLING SYSTEM,Raito Kogyo s 3D Navigational Drilling System has realized three dimensional free curve drilling using
dual-wall rod string. This system has been developed to respond to the necessity to drill boreholes incongested urban subsurface conditions. By employing dual-wall rod system, this system is flexibly
applied to existing geotechnical and geo-environmental methods that employ borehole drilling, such as
chemical grouting and various environmental cleanup methods.

ADVANTAGES
Raito Kogyo's 3D Navigational Drilling system:
1 Enables ground improvement and soil remediation under orbehind existing structures without affecting facility operation ordamaging underground structures.

drill
line

2 Is flexibly applied to the conventional methods that employ
borehole drilling.

3D drilling performance test (S-shaped curve)

3 Drills a sharp-curve borehole (e.g. 20m radius)
4 Drills over a long-distance.
5 Circumvents underground obstacles.

drill
line

6 Monitors navigation accurately with special bit locator system.

3D drilling performance test (long distance)

COMPARISON WITH CONVENTIONAL METHODS
To perform ground improvement under existing structures, two methods have been normallyemployed: 1) drill inclined grout holes from the ground surface or 2) drill horizontal grout holes froma shaft excavated nearby. By using 3D navigational drilling system, horizontal grout holes can beinstalled from the surface without excavating a shaft.

Ground improvement to stabilize a sewage main

Ground improvement underneath existing buildings
Flexible borehole alignment

NAVIGATIONAL DRILLING SYSTEM
BIT LOCATOR AND STEERING SYSTEM    "    #                         1"!        "                  %       %                                       

TYPICAL DRILL SEQUENCE    -                                             /       !      
2       123

    "        )                 * +(  "       #   

4APPLICATION!       "  #            $   #        "      #      %     "%      %    %        "     &    $  "           
Ground improvement      "%   )%      %  "% "%  

Soil and groundwater cleanup      %   "%            (# "     '  $   
$   ' ( %      #   "  #  "      P3

NAVIシステム 57期

天地297ミリ×左右420ミリ

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4-2-35, Kudankita, Chiyoda-ku,Tokyo 102-8236 JAPANTEL. +813-3265-2506
FAX. +813-3230-1709
E-mail overseas@raito.co.jp
URL http://www.raito.co.jp
2006.06
60.06

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