Ranging from 3’’ up to 6’’, the Xs FP (forepoling) system and Xs FPH (forepoling hybrid) are used in umbrella, drainage and injection applications with top hammer or DTH drills. These systems were developed mainly for use in tunnelling applications in unconsolidated formations. The Xs FPH has more impact surface and greater air channels for evacuation of the cuttings. This system can be used with standard crowns or with a special crown adapted for drilling through clay.
The driver bit comes in 2 different versions; with locking grooves for vertical drilling and without locking grooves for horizontal drilling. The version without the locking grooves is called the NLS (no locking system). The purpose of the driver bit is to transmit the rotation and the percussion to the crown bit only.
The NLS is proven to be the best and the most user friendly system on the market. When the drilling phase has been completed, it is very easy to disengage from the crown bit by simply pulling straight back.