Derrick is one of the important parts of drilling and production machinery. As shown in Figure 3-36, it is used to place and hang the crane (Figure 3-37), traveling block, hook, lifting ring, tongs, elevators and other lifting equipment and tools, and to lift and store drill pipes, tubing or sucker rods during drilling and oil production.
Figure 3-35 Drilling System 1- Faucet; 2-Kelly; 3-Winch; 4- turntable; 5- crown block; 6— Derrick; 7-traveling car; 8- tick; 9- Hose; 10- riser; 1 1- power machine; 12- mud pump; 13- Mud pit; 14-mud tank; 15-cement ring; 16-casing; 17- drill pipe; 18-drilling; 19-Mud flow; 20— Drill collar; 2 1 bit
Figure 3-36 Drilling ground equipment 1- crown block; 2— Cantilever lifting rope; 3-drilling pipeline; 4- second floor platform; 5- Travel car; 6— Top drive; 7— Derrick; 8-Kelly; 9— Driller's wing; 10-BOP; 1 1- water tank; 12-cable tray; 13- generator set; 14- oil storage tank; 15- electrical control room; 16-mud pump; 17- hopper box; 18-mud tank; 19-Mud pit; 20— Centrifuge; 2 1- vibrating screen; 22— Throttle manifold; 23— Pipeline ramp; 24— Drill pipe rack; 25— The battery winch is the core component of the drilling rig, as shown in Figure 3-38. Winches are not only used to hoist and lower drilling tools and casings, but also used to control WOB during drilling and to support the whole derrick. The winch with sand drum is also responsible for extracting core barrel and testing oil, and often acts as a speed change mechanism or an intermediate transmission mechanism of the turntable.
The winch, rotary table and drilling pump of drilling rig work alternately, and the working machinery often starts and stops, so the clutches in these transmission systems act frequently, especially when tripping in deep wells. At present, the main brake is hydraulic disc brake. As shown in Figure 3-39, DC electric drilling rig and chain drive drilling rig also need auxiliary braking. The general jaw clutch and manual friction clutch can not meet the requirements of such heavy load operation, and the electromagnetic clutch driven by speed regulation is usually used.
Figure 3-37 Crown Block
Figure 3-38 Winch
Figure 3-39 Hydraulic Disc Brake 1- Brake Disc; 2- safety tongs; 3— Working pliers; Figure 3-40 is the old brake mechanism diagram. When braking, the brake handle 4 is operated to rotate the transmission rod 3, and the movable end of the brake band 1 is pulled by the crank to hold the brake drum 2. Twist the brake handle to control the driller valve 5 to start the air brake. Air braking plays a labor-saving role. The balance beam 6 is used to balance the tightness of the left and right brake bands to ensure uniform stress. When the gap between the brake band and the brake drum is increased due to the wear of the brake block, and the braking angle of the brake handle is too low, it can be adjusted to the initial gap by adjusting the screw 7. The brake band 1 is made of spring leaf and hung on the winch shell with screws with springs, which can be separated from the brake drum evenly when it is not working; Heat-resistant and wear-resistant brake pads are riveted on the steel belt. American winches generally adopt double lever mechanism, which has large force ratio and is very labor-saving to operate.
A lot of kinetic energy will be generated in the process of tripping in, and the winch brake belt alone is not fully competent for the transformation of these energies. In deep well drilling rig, auxiliary brake, such as water brake or electromagnetic brake, plays a very important role.
Manual wellhead tools, such as tongs, elevators and slips, are needed to trip and loosen drilling tools. The hanging tongs are composed of several tongs heads and tongs handles inlaid with toothed plates, and the tongs heads and tongs handles are connected with each other through hinges. The tongs are used to loosen the connection threads of various downhole tools that make up the drill string, such as drill pipes and drill collars, as shown in Figure 3-4 1. The tongs are used in pairs (one in front of the other) and screwed with a cat's head rope. Elevator is used to hang, lift and lower drill string. The inside diameter of elevator is slightly larger than the outside diameter of drill pipe, but smaller than the outside diameter of drill pipe joint. When working, the drill string joint is stuck and cannot be tripped. When tightening or loosening the drill string, the drill string located in the well must be temporarily suspended on the rotary table. Slips installed in the rotary bushing are used to clamp the drill pipe and hang the drill string.
Figure 3-40 Schematic Diagram of Brake Mechanism 1- Brake Band; 2- Brake drum; 3- lever; 4- Brake handle; 5— Driller valve; 6-balance beam; 7— Travel limit screw; 8- gas filament; 9-Spring
Figure 3-4 1 Hydraulic casing tongs With the rapid increase in the number of deep wells, hard formations and offshore drilling, the workload of tripping operations has obviously increased. Using the above-mentioned manual wellhead tools to break the thread is labor-intensive, inefficient and unsafe, and needs to be improved urgently. At present, various forms of power tongs and power slips have been widely used in drilling production. It accelerates the tripping speed, reduces the labor intensity of workers, and lays a foundation for further realizing the overall mechanization and automation of drilling work.
2 Rotating system In order to continuously break rocks by rotating drilling tools, the drilling rig is also equipped with a top drive (the old drilling rig uses a turntable, as shown in Figure 3-42) and a faucet, and the downhole is equipped with a drill string and a drill bit, and sometimes a bottom hole power drilling tool is used.
Figure 3-42 Turntable of Oil Drilling Rig
Fig. 3-43 Norwegian DDM-650 top drive drilling system 1- faucet; 2- motor; 3-gear reducer; 4- mechanical gearbox; 5— Drill pipe control joint; 6— Rotating ring operated by drill pipe; 7— Elevator position motor; 8— Hydraulic cylinder; 9— Hanger; 10-elevator operation actuator; 11-expansion joint; 12- expansion joint support group; 13- Remote control of internal blowout preventer; 14- torque wrench; 15— Drill pipe elevator For many years, the kelly, drilling tools and drill bits have been driven to rotate by the rotary table of the drilling rig. In recent years, with the continuous development of drilling equipment and technology, in order to better meet the needs of drilling special technology wells, in the 1980s, a drilling device was developed abroad, which combined a faucet with a motor to drive the drilling tool and drill bit to rotate in the upper part of the derrick space and feed downward along the guide rails placed in the derrick. At the same time, it is equipped with a screw device for loading and unloading drill pipes, which can complete the rotation of downhole drill string, circulating drilling fluid, loading and unloading drill pipes, tripping in and rotating left and right. The device is suspended under the traveling system, which directly rotates the drilling tool and feeds it downward along the special guide rail in the derrick, thus replacing the rotary table and Kelly to complete various drilling operations such as rotary drilling, circulating drilling fluid, connecting drill pipes, loading and unloading drill strings, etc. Therefore, the top drive drilling system is mainly composed of three parts: faucet drilling motor assembly, guide pulley assembly and tripping device on drill pipe, as shown in Figure 3-43.
Because the device is located under the traveling block of the drilling rig and the driving position is higher than the original turntable position, it is called top-driven drilling device. Top-driven drilling device can be connected to a column (three drill pipes form a column) for drilling, which saves the routine operation of connecting and unloading Kelly during rotary drilling, as shown in Figure 3-44, which saves drilling time by 20% ~ 25% and reduces the labor intensity of workers and the personal accident risk of operators. When drilling with the top drive device, the drilling fluid can be circulated and rotated while lifting and lowering the drilling tools, which is beneficial to the treatment of downhole complex situations and accidents during drilling and is very beneficial to the drilling construction of deep wells and special technology wells. Drilling with top drive device makes the drilling floor look brand-new and creates conditions for automatic drilling in the future.
3 circulation system In order to remove the broken rocks at the bottom of the well with flushing fluid at any time and ensure continuous drilling, the drilling rig is equipped with a circulation system, as shown in Figure 3-45. Including drilling pump, ground manifold, mud pit and mud tank, mud purification equipment, mud mixing equipment, etc. In jet drilling and turbine drilling, the circulating system also undertakes the task of transmitting power. Drilling pump is used to circulate mud during drilling. At present, the basic form is reciprocating pump. Therefore, drilling pump can be regarded as a typical reciprocating pump.
Figure 3-44 shows that the connection part of the lower part of the top-drive single-rod drill pipe is a drill bit, which is the main tool for breaking rocks. Figure 3-46 shows a three-cone bit, which is mainly composed of claw (also called claw), cone and bearing. In addition, there is an oil storage compensation system for lubricating bearings, seals and jet drilling nozzles with oil. The teeth are distributed on the cone of the roller bit. If a milling cutter is used to mill teeth on the bit body, it is called a gear milling or steel tooth drill. If cemented carbide (tungsten cobalt alloy) is embedded in the cone, it is called embedded bit. Three cones of a three-cone bit have different shapes, the first cone has a complete shape, the second cone has some truncated tops, and the third cone has a larger truncated top. There are two kinds of bearings used in roller bit: rolling bearing and sliding bearing, and the radial size of sliding bearing is smaller. Bearings should be sealed to prevent mud and sand from entering the bearing cavity. A new type of drill bit widely used now is a "four in one" drill bit with cemented carbide insert, bearing seal, sliding bearing and injection hole. When the roller cone bit works at the bottom of the well, the roller cone not only revolves around the bit axis, but also rotates around its own axis, and there is still sliding at the bottom of the well. Therefore, the way of rock crushing by roller bit is the joint action of impact, compression and shear. Roller bits can drill both soft and hard formations. Different roller bits can be selected according to formation characteristics and lithology hardness grade.
Figure 3-45 Circulation System
Fig. 3-46 L-shaped bit body with three-cone bit structure; 2 claws; 3 cones; 4- orifice plate; 5- bolt; 6 rolls; 7 goals; 8 The working principle of locating pin drilling pump is that the engine drives the main shaft of the pump to rotate through transmission parts such as belts and gears, and the connecting rod connected with the main shaft drives the piston to move back and forth in the piston cylinder, so that negative pressure is formed in the cylinder, and the liquid in the suction pool pushes open the suction valve under the action of atmospheric pressure on the liquid surface and enters the cylinder until the piston moves to the rightmost position (Figure 3-47). This working process is called the suction process of the pump. When the piston moves to the rightmost position (i.e. crank rotation 180), the piston starts to move to the left, and the liquid in the liquid cylinder is squeezed, and the pressure rises, so that the suction valve is closed, the discharge valve is squeezed out, and the liquid is pushed out by the piston and enters the liquid discharge tank through the discharge valve and the discharge pipe. This working process is called pump discharge process.
Figure 3-47 Three-cylinder drilling pump reciprocating pump is widely used in petroleum industry. Oil mines often need to transport liquids with high viscosity, high specific gravity and high sand content under high pressure, but the flow rate is relatively small. From the comparison of working characteristics of various pumps, it can be seen that reciprocating pump is more suitable for this situation. Reciprocating pump is used to circulate mud and inject cementing cement during drilling. In the process of oil production, it is used for crude oil transportation, well washing, water injection and formation fracturing. Deep well pump in pumping equipment is also a kind of reciprocating pump with special structure. Therefore, reciprocating pump is one of the key equipment commonly used in oil mines.
During drilling, cuttings produced at the bottom of the well are brought to the surface by drilling fluid, which requires timely removal of cuttings from drilling fluid. Vibrating screen is one of several necessary equipment for removing drilling cuttings in drilling. Its working principle is that the vibration motor rotates to drive the eccentric shaft to move so that the screen vibrates to separate cuttings, as shown in Figure 3-48.
4 Other auxiliary equipment (1) power equipment.
Power equipment is power equipment that drives winches, turntables, drilling pumps and other working machines, some of which are diesel engines and some are AC or DC motors.
Figure 3-48 Self-synchronizing linear sieve 1- exciter; 2- sieve box; 3- sieve surface; 4- Support spring; 5— Drive system of excitation motor (2).
The main task of the transmission system is to transfer and distribute the energy of the engine to various working machines. Because there is a certain gap between the characteristics of the engine and the characteristics required by the working machine, it is required that the transmission system must include mechanisms such as deceleration, combination, commutation and speed change. Sometimes on the basis of mechanical transmission, there are hydraulic transmission, hydraulic transmission or electric transmission devices (electromagnetic clutches).
(3) Control system.
In order to command the coordination of all systems, the whole rig is also equipped with various control devices, such as mechanical, hydraulic or electrical control devices, centralized console and observation and recording instruments.
(4) base.
The base includes drilling floor base, engine room base and drilling pump base. The base of the vehicle-mounted drilling rig is the chassis of a car or trailer.
(5) auxiliary equipment.
Auxiliary equipment generally includes air compression equipment, rat hole drilling equipment, wellhead blowout preventer, auxiliary power generation equipment (used for mechanized equipment, air compressor and lighting), auxiliary lifting equipment, mobile houses (material warehouse, repair room, duty room, etc.). ), and drilling in cold areas requires insulation equipment.
Blowout preventer is an important equipment to open high-pressure oil and gas reservoirs and ensure safe production during oil drilling. According to different functions, BOPs can be divided into double ram (dual-purpose) BOPs, rotary BOPs and universal BOPs. If a high-pressure oil and gas reservoir is suddenly encountered during drilling, the well can be sealed with double brake plates or universal blowout preventer to prevent blowout accidents. When all the drilling tools are out of the well, the well can be sealed with universal or fully sealed ram BOPs, and the universal and double ram BOPs can be used together to realize drilling while spraying. Blowout may occur when drilling high-pressure oil and gas reservoirs, causing serious accidents. In order to control the injection of drilling fluid, oil, gas and water in a well, a blowout preventer is usually installed under the drilling floor. At present, the drilling rigs produced at home and abroad are equipped with a complete set of blowout preventer systems. Generally, each drilling rig is equipped with 3 ~ 4 sets of BOPs, such as ram BOPs, rotary BOPs and universal BOPs. There are three kinds of ram BOPs: single ram, double ram and triple ram. According to the different gate structures, there are three types: perforated gate, blind gate and shear gate. There is a hole in the center of the drilling rammer core. When a blowout occurs during drilling, the annular space between the drill string and casing can be sealed to prevent drilling fluid, oil, gas and water from spraying out of the well. It is also called drill pipe blowout preventer. Fully enclosed ram BOP is also called fully enclosed BOP. Its core can directly seal the wellhead, and the wellhead can be used without drill pipe. Scissor gate can cut off the pipe in the well in an emergency to ensure the safety of the wellhead.
As shown in Figure 3-49, the ram structure diagram shows that (a) is a fully sealed ram and (b) is a semi-sealed ram, so it is also called dual-purpose BOP (fully sealed and semi-sealed); When there are drilling tools in the well, the annular space between casing (or borehole wall) and drilling tools can be sealed, which is called semi-sealing; When there is no drilling tool in the well, the wellhead can be closed. Under special circumstances, the shearing ram can be used to cut off the drilling tool and seal the well, which is called full sealing. When the well is shut in, the bypass outlet can be connected to the manifold for drilling fluid circulation, throttling and blowout, well killing and other operations. The ram consists of rubber core, ram body, cover plate and screws. The ram body is made of alloy steel and can withstand high pressure; The rubber core has high strength and toughness, ensuring good sealing performance under high pressure.
Figure 3-49 Schematic diagram of ram structure The structural feature of the rotary BOP is that the rubber core can rotate with the drill pipe while gripping it, meeting the technological requirements of drilling while spraying, and sealing the annular space between the drill pipe and the casing. The rubber core of the universal blowout preventer can seal any drilling tool in a few seconds, and strive for precious emergency time. When the drilling rig is equipped with ram blowout preventer, rotary blowout preventer and universal blowout preventer, they can be used independently or overlapped, and new drilling technologies such as drilling while spraying, tripping without killing and reverse circulation drilling can be realized. Most BOPs are equipped with manual and hydraulic control devices for remote control in case of emergency.