PDGC50: Photo-Electric Density

PDGC50 provides a classic triple-spacing sidewall focussed formation density measurement, with the additional advantage of a incorporating a photo-electric effect energy detection window on the medium-spacing detector.

The photoelectric effect (Pe) measurement is a reliable indication of the apparent formation atomic number, meaning that formation lithology and an accurate porosity can often be deduced directly from the results given by the probe. When the Pe log results are combined with those obtained from other probes (eg. spectral gamma) a considerable number of specific « heavy » minerals can be identified.

A gamma ray source (Cs137, typically 3.7 GBq), is fixed to the lower extremity of the probe during logging. The source capsule itself is supplied separately by a specialist partner.

The mechanical side-walling arm provides a caliper measurement, useful for diameter correction purposes and mud-cake evaluation, and a natural gamma log is also obtained by means of a scintillation detector located in the uppermost part of the probe body.

Contact us to get a quote or request more information.


Technical Specifications

✓ Diameter : 50 mm

Length : 2500 mm

Weight : 20 Kg

Max. Temp : 70°C

Max. Pressure : 200 bar

Sensors Parameters

Long-spacing density : 25 x 50 mm NaI(Tl) crystal

 Medium-spacing density + Pe : 10 x 50 mm NaI(Tl) crystal

Bed resolution density : 10 x 25 mm NaI(Tl) crystal

 Caliper range : 50 to 450 mm

Natural gamma detector : 25 x 50 mm NaI(Tl) crystal

Options And Accessories

 Workshop calibration blocks : plexiglass, aluminium, iron

 Caliper calibration jig

Borehole Conditions

Open uncased borehole

Dry or fluid-filled (preferred) borehole


Lim designs, produces and commercializes measuring instruments and solutions dedicated to drilling.



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