When doing mechanical CPT tests, the CPT sounding tubes are pushed into the soil by means of a mechanical or electrical measuring head. At the end of each test traditionally the tubes are pulled up by means of either a pulling kit (pulling bowl with pulling piece) or a ball clamp.
The largest disadvantage of the pulling kit is the fact that working with it is quite laborious. A ball clamp is quicker perhaps, but it jams quite rapidly (and does not come loose unless brutal force is applied) and damages the tubes.
To overcome these disadvantages Gouda-Geo purposely developed a pulling clamp for 36 mm CPT sounding tubes. The pulling clamp has a pulling capacity of 260 kN and fits in the yoke of a 100 kN as well as a 200 kN CPT penetrometer pusher.
The removable clamping blocks are made of hard metal. The force, applied on the tubes by the clamp, is distributed evenly by the clamping blocks over the gripping area. This guarantees excellent seizing and prevents damaging or deformation of the sounding tube.
Pulling CPT sounding tubes has eventually become an easy and quick job.