Equipment for industrial water wells drilling, structural exploration drilling for hydrocarbon raw materials and deep wells of technical water supply, presented on the Russian market, until recently was limited to two models of domestic production units. We are talking about the BA-15.06 and URB 3A3 mobile rotary drilling rigs manufactured by the Kungur Mechanical Plant. Rigs with classical rotary tables did not lose their positions, despite the fact that at the end of the last century imported hydraulically driven Rigs from such well-known manufacturers as Pracla, Wellco Drill and AGBO came into the Russian market. When constructing industrial wells to a depth of over 300 meters with a final diameter of over 190 mm, modern Rigs with a movable rotary heads lose to machines with rotary tables in reliability and efficiency, and their obvious advantages, such as ergonomics, high maintainability, ease of operation, saturation with means of mechanization of auxiliary operations, are practically are leveled by the considerable mass of the equipment and its high price. Thus, the weight of the G-600 AGBO hydraulic Rig, intended for drilling to a depth of 600 meters, reaches 26 tons, while the BA15 machine with a rotary table weighs no more than 19 tons and provides drilling to 700 meters. Such a difference in weight is explained by the fact that, in contrast to Rigs with movable rotary heads, the masts of Rigs with rotary tables are not designed to transfer axial loads to the drilling tool and do not perceive torque - the rotary table is not mounted on the feeder carriage, but on the Rig frame and the load on the face is created only by the weight of the drilling tool. The release of the mast of the Rigs with rotary tables from the function of the feed frame allows not only to ease it, but also to increase its height. At the same time, the course of supplying the drilling tool during drilling is not limited to the feed stroke, and during tripping and well casing operations with rods of considerable length are possible. When drilling deep wells, especially in soft and medium rocks, high accuracy is required to control the axial load on the rock-destruction tool, in order to avoid arbitrary distortion of the stems and destruction of the drill strings. Rigs with rotary tables, complete with systems for measuring the weight of the drilling tool, provide such control, and due to the fact that the load on the bit is created only by the weight of the drilling tool, the drill winch controlled by the tension of the rope and the drill string is installed over the bit, the drill string is in operation in a stretched condition. Drilling in the mode of an unloaded column is also possible with movable rotary heads, however, the hydraulic system and instrumentation equipment becomes more complex and expensive. In 2017 Geomash Companies Group decided to start the development of mobile rotary installations for drilling exploration and production wells up to 1000 meters deep and by the middle of 2019 introduced to the market two models of a new line of drilling rigs – URB-25 and URB-40.
Comparative characteristics rotary drilling rigs Geomash
Main technical characteristics URB-25 URB-40
Drive power, kW 169 200
Load on hook, allowable, ton 25 40 Conventional drilling depth, m 800 1000 Recommended initial drilling diameter, mm 535 780 Recommended final drilling diameter, mm 244.5 190.5
The length of the drill pipe / candles, m 7/12 6/12
Casing length, m 12 12
The length of the leading pipe ("square"), m 7.8 7.0
Traction winch force, ts 6.5 7.5
Lifting capacity of tackle block drilling unit, ton 25 30
Lifting capacity of the swivel, ts 25 30
Loading capacity of the cargo talevy block, 25 40
Maximum torque, kgf.m 1600 1600
Rotation speed of the rotor table, rev / min 18 ... 220 0 ..180 Traction auxiliary winch /main drum, ton 2.2 2.0
Drive power, kW 169 200
Load on hook, allowable, ton 25 40 Conventional drilling depth, m 800 1000 Recommended initial drilling diameter, mm 535 780 Recommended final drilling diameter, mm 244.5 190.5
The URB-25 and URB-40 units are intended for the construction of production wells for industrial water supply, structural and prospecting wells for hydrocarbon raw materials, production wells for in-situ leaching of mineral raw materials, shafts for degassing underground mining, ventilation shafts, water wells and other wells for technical purposes. New Rigs, depending on the configuration, implement both rotary drilling with direct flushing, DTH drilling, Air-lift drilling. Depending on the version, the URB-25 and URB-40 can be mounted on trucks and long-wheelbase automobile trailers and driven from the main engines of transport bases, or from autonomous power units. A set of technological equipment is available, including mud pumps, screw compressors, trailed mud pump and compressor blocks, trailed pipe blocks, means of mechanization of auxiliary operations. The product line launched with the URB-25 and URB-40, organically complementing the size range of domestic rotary units, no doubt has the potential for further development.
Old Man Rotor early to retire!