Roller bits. GrandPro product line

Large diameter chisels (from 393.7 mm) with premium premium sealed support. Designed for multiple drilling of the upper sections of the well (direction, conductor). The bits of this product line have an increased resource under forced drilling conditions. The bits of the GrandPro product line use both sliding bearings and rolling bearings. In the sliding bearing, the components (sleeve, washer) are made of anti-friction wear-resistant material and are coated with a layer of silver over the entire surface, which increases the resource of the support.