Bürkle Mole Drill Head, Sand, replacement head for soil sampler, iron/steel, 5350-1020

Of all soil types, loose sand is the least likely to stay in a drill head on its own. Without sufficient surface area on the flanks, the material trickles out again as the drill is pulled out, before the sample even reaches the surface. The Mole Sand drill head addresses this with wide flanks, which give the sand a firmer grip without making the drill head any harder to turn into the ground.

Wide flanks as a bearing surface

Compared to the narrow version designed for clay and damp soils, the Sand drill head has wider flanks with a larger bearing surface. Sand holds on comparatively well between these flanks because the grains have more contact with the metal than with a narrow profile. The result is a sample that hasn’t already trickled halfway out by the time it reaches the sample container from the borehole.

Handling in loose material

In sandy soils, the method of extraction has a more significant impact than in cohesive material. If the drill head is pulled out of the borehole swiftly and as vertically as possible, more sample remains in the flanks than if it tilts whilst being pulled out or scrapes along the side of the borehole. This handling method applies to all drill heads in the Maulwurf system, but has the most significant effect on the sample quantity when dealing with dry, loose sand.

Use with the ‘Maulwurf’ handle

Like all drill heads in the series, this model is also an interchangeable part for the Maulwurf handle with shaft and cannot be used without it. The handle is 750 millimetres long; for deeper drilling, a 100-centimetre extension (5350-1010) increases the reach without the need to replace the handle itself.

Typical applications

The sand drill head is suitable for sites where the soil is predominantly loose and has low cohesion, including:

• Soil sampling in sandy, low-cohesion soils
• Investigating sites with sandy topsoil prior to construction projects
• Sampling in sand pits and their surrounding areas
• Environmental analysis at sites with slightly permeable, sandy subsoil

Differences from other drill bits

If the sand is coarser and the soil generally drier – for example, near gravel pits or during very dry summer periods – the ‘Coarse Sand’ drill head, with its even wider flanks, collects more material. If, on the other hand, the soil is moist and cohesive, the ‘Clay and Moist Soils’ drill head is the correct choice; its narrow flanks are designed for sticky rather than loose material. In areas where both soil types alternate, the ‘Combination’ drill head covers both soil types with a single head.

Material and handling in the field

Like the handle itself, this drill head is made of iron/steel, with no electronics or battery. This makes it resistant to field conditions; there is no charge level to monitor and no calibration to check. Between uses, storing it at room temperature is sufficient; it is particularly important to tap off any adhering sand before stowing it away, so that it does not spread throughout the vehicle or storage area.

Technical details

Contents

• Mole drill head, sand

The Mole handle with rod is not included in the scope of delivery and must either be provided separately or ordered at the same time.

Service and procurement

For sites that have both sandy and finer sections, LT Laborhandel can, on request, supply the sand drill head together with other drill heads from the Mole range, ensuring that the right head for every type of soil encountered is to hand on site. If you are unsure which drill head is suitable for your site, please contact LT Laborhandel directly for assistance.