The MH-64 & MH-52

Case History

Mechanical Sources for Medium-scale
Borehole Seismic Investigations

The MH-64 and MH-52 are borehole hammers for geotechnical cross-hole seismic surveys. The seismic signals are conveyed to the earth through the water filling the borehole by means of a pulse converter. The investigation range is from 50 to 150 meters, depending on the seismic transparency of the rock or soil. The minimum borehole diameter is 56 mm (BQ) for the MH-52 and 75 mm (NQ) for the MH-64. The recommended depth is maximum 200m. The hammers are designed to be used in the ‘fast stack’ mode, the blow interval being adjustable between 1 and 5 seconds. Both models are equipped with electric motors and piezoelectric trigger sensors with a timing accuracy of a few tens of microseconds.

Frequency Range 200 - 1500 Hz
Maximum Temperature: 75° C
Any hole inclinatione: -
Power: 220 V/50 Hz - 5A
MH 62 MH52
Working Voltage: 24 -32 V DC 24 -32 V DC
Repetition Rate: 3 - 6 s 2 - 6 s
Maximimum Working Depth: 250m - unclamped
1000m - clamped
250m - unclamped
1000m - clamped
Minimum Hole Diameter: 62mm 56mm
Total Mass: 35 - 40 kg 20 - 27 kg
Hammer Mass: 1 - 4 kg 0.8 - 2.8 kg
Outer Diameter: 62mm 52mm
Length: 1930 - 2150 mm 1850 mm