The rapid spread of ground source heating systems over the past years has led to an increased use of Comacchio rigs for geothermal drilling applications utilizing dual head drilling systems. These systems are based on the use of two separate drilling and casing heads that rotate in opposite directions, allowing both to be advanced simultaneously.
Particularly suitable for loose or sandy soils, this advanced drilling rigs incorporate a lower head, which allows the rotation of the outer casings and an upper head, which drives the inner rod battery and the drilling tool. The simultaneous movement and counter-rotation of the two heads allows for a fast and homogeneous feed and facilitates the removal of the cuttings.
This drilling methodology offers multiple advantages that include technical performance (hole accuracy and penetration rate, overcoming unstable ground conditions) as well as environmental considerations (groundwater protection, cuttings collection).
The Comacchio range includes as much as seven crawler and truck mounted hydraulic drilling rigs, with a pull up capacity ranging from 10 to 30 tonnes, developed to perform this type of drilling technology. These systems have been developed by Comacchio for their compact size, high productivity and easier handling of the equipment. They also allow for a better control over the environmental impact of drilling i.e. through the installation of sealed cuttings collection systems. Along this, the development of rod handling systems has allowed mechanizing and automating, partly or completely, the handling of rods and casings, with a view to creating a safer working environment and increasing production levels.