Geothermal Scale Catcher 

The Geothermal Scale Catcher collects samples of scales that form inside geothermal wells. This happens through the deposition of dissolved minerals such as calcite and silica during the flashing process as geothermal fluids travel up the well bore.

The scale catcher consists of a scale collection bowl with a number of openings to allow scale to enter and settle. Around each opening there are jaws designed to scrape out samples of scale as the sampler is moved up or down along the scale surface. The top part of the tool is designed as a sliding hammer or jar, capable of imparting sharp upward or downward forces as the wireline is pulled or slackened quickly. The sliding jar can also be useful in freeing the tool if it should become wedged.

The tool is lowered into the well to the required zone and the sample is collected. The tool is then brought back to the surface and the sample retrieved from the bowl for chemical analysis.


Length: 1.25 m
Body Diameter: 48 mm
Max Diameter: 68 mm


The scale catcher is a completely mechanical device with no elastomeric parts. It can therefore be exposed to any well conditions likely to be encountered in geothermal wells.

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