Drill pipes are designed for well equipment
Drill pipes are designed for equipmentgas and oil wells. With the help of such equipment, a rock-breaking tool is lifted and lowered into the hole, a torque is transmitted, a load (axial) is applied to the tool, and compressed air or washing solution is injected into the face. Their production is mainly carried out according to the standards of GOST No. 50278-92. According to this normative act, the products are made of steel, are formed in a seamless way and have planted ends, to which locks are welded.
Drill pipes can have different typesplanted parts, including: internal, external or combined landing (designated as MF, SC or PC, respectively). The products of the PV group are manufactured with a nominal outer diameter from 73 to 101.6 mm, wall thicknesses from 8.4 to 11.4 mm, the calculated mass of one meter of smooth pipe is from about 14 to 22 kg.
Diameters of drill pipes of class PC reachnominal 139.7 mm (the minimum value is 114.3 mm). A pipes with external landing (PN) have a smaller nominal diameter in accordance with the above-mentioned GOST (127 mm). In addition to the diameter, for parameters for pipes, parameters such as the diameter of the lock (manufactured according to GOST 27 834) and the diameter of the welded joint, including the inner diameter and the diameter under the elevator, are considered. Another important parameter is the length, which is represented by three groups: from 5.9 meters to 6.3, from 8 to 8.6 meters and from 11.9 to 12.5 meters. Modern production makes it possible to produce pipes of both larger and shorter lengths, but in this case they will not meet the established standards.
Quality drill pipes must be madeso that on their surface there are no cracks, bundles, shells and other defects. Correct these flaws can only be along the axis of the pipe, while sealing, zachekanka and welding problem areas are not allowed, they can only be cleaned or cut down.
The production of drill pipes is organized in such a way,so that the mass fraction of phosphorus and sulfur in each melting is carefully controlled. If the enterprise uses third-party raw materials, then the company-manufacturer requires documents on the conformity of quality. Today some companies produce products with an internal coating (for example, TK-34R), which allows to protect the pipes from abrasion and corrosion wear, rack corrosion, reduce the likelihood of fatigue failure, as well as hydraulic losses during drilling. The coating surface is applied in a powdered way and allows the pipe to withstand more than 500 operating hours at temperatures above 150 ° C, to achieve impact resistance of more than 8 J at a temperature of 20 ° C,
Drill pipes are known as equipment,which often breaks due to wear of the diameter of the lock (outdoor, up to 60% of all cases). The remaining parts of the pipe remain suitable for operation. Recently, methods of carbide-tipped welding of locks have been used to solve this problem. This avoids cracks generated in high voltage conditions and other factors of extreme exploitation.