US 4,907,661 A · Drill pipe tubing and casing protectors

Abstract

Each section (1) of a drill pipe string carries a substantially annular protector (2) that is movable in a freely rotatable manner around (4) the longitudinal axis of the section (1) concerned. Each protector (2) is also movable lengthwise (3) throughout the length of the section (1) between junctions at its opposite ends or to an extent that is limited by retaining rings secured in appropriate positions around the section (1). Each protector (2) is formed from a relatively hard material having a very low co-efficient of friction, such as polytetrafluoroethylene, and is advantageously produced in two separable halves (FIG. 3) to facilitate embracing assembly around, or quick removal from, the co-operating pipe section (1). If necessary, the protectors (2) may be formed throughout their axial thicknesses with flutes significantly to reduce the fluid flow constraint produced by the presence of the protectors (2).

Claims7

Dependent claims

A floating drill pipe tubing and casing protector comprising:

(a) at least one annular protector arranged to embrace a drill pipe section, wherein said annular protector is constructed and arranged so as to be freely rotatable around the longitudinal axis of the drill pipe section and displaceable lengthwise along said drill pipe section;
said protector being of a polytetraflourethylene material and comprising two juxtaposed halves, each having an upper section and a lower section, each half comprising:
(i) a convex inner surface and a convex outer surface, the inner and outer surfaces having flutes formed through the axial thickness thereof for the passage of fluid therethrough;
(ii) at least one slot formed in the upper and the lower sections of each half;
the slots being lined with a stainless steel sleeve, the sleeve having a bore formed therein for receipt of a recessed fastening means, and
(b) retaining means associated with the protector to limit the extent of the lengthwise displaceability of the protector along the drill pipe section.

3 more elements

Dependencies are inferred from the claim text.

Drill pipe tubing and casing protectors

Life of this patent

Drill pipe tubing and casing protectors

Life of this patent

Abstract

Claims7