PROTECTOR Russian patent published in 1998 - IPC

FIELD: oil and gas production industry. SUBSTANCE: this relates to drilling bore-holes, especially deep and superdeep bore-holes intended for production of oil and gas. It can be used for protection of casing string from wear during operation. Protector is reliable and durable in service. Device has body with connecting threads. Made in body are recesses in the form of longitudinal slots, it can be for example four slots, located over perimeter of body circumference and directed along its axis for possible accommodation in them of wearing (replaceable) components. Provided both in body and in wearing components are symmetrical grooves in direction of perimeter of body circumference for possible accommodation in them of prestressed rings. In addition, outer surface of wearing (replaceable) components is made according to radius which corresponds to radius of casing string. Aforesaid wearing components are made of antifriction material, such as textolite, bronze, polyurethane, etc. EFFECT: higher efficiency. 1 cl, 4 dwg