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An oil drilling rig is a large-scale mechanical equipment used in oil and gas drilling operations. Its main function is to drive drilling tools to break underground rocks and drill wellbores, providing channels for subsequent exploitation and thereby realizing the exploration and development of oil and gas resources. Its core functions include hoisting and lowering drilling tools, rotary drilling, and circulating well cleaning. It is mainly composed of power machines, transmission mechanisms, working machines, and auxiliary equipment. Classified by operation scenarios, it can be divided into onshore oil drilling rigs and offshore oil drilling rigs, which are key infrastructure for ensuring global oil and gas supply. Core Component Systems A drilling rig consists of eight major systems: the hoisting system controls the lifting and lowering of drilling tools via drawworks and pulley blocks; the rotary system drives the drill bit to break rock formations; the circulation system uses high-pressure mud to remove cuttings; the power and transmission system provides power distribution; the control system coordinates equipment operation; the derrick and substructure provide support; and auxiliary equipment includes safety devices such as blowout preventers (BOP). Core components include the derrick, crown block, rotary table, and various types of drill bits. Top drive drilling rigs adopt top drive (power swivel) technology, which improves drilling efficiency and is suitable for deep well operations. During operation, mud pumps circulate mud to cool the drill bit, and braking mechanisms adjust drilling parameters. Ⅰ. Hoisting System The hoisting system is equipped to hoist and lower drilling tools, run casing, control weight on bit (WOB), and feed drilling tools. It includes the drawworks, auxiliary brakes, crown block, traveling block, hook, wire rope, and various tools such as elevator links, elevators, tongs, and slips. When hoisting, the drawworks drum winds the wire rope; the crown block and traveling block form a secondary pulley system. The hook rises to lift the drilling tools through tools like elevator links and elevators. When lowering, the drilling tools or casing string descends by its own weight, and the lowering speed of the hook is controlled by the drawworks' braking mechanism and auxiliary brakes. During normal drilling, the feed speed of the drilling tools is controlled by the braking mechanism, and a portion of the drilling tool weight is applied to the drill bit as WOB to break rock formations. Ⅱ. Rotary System The rotary system is a typical system of a rotary table drilling rig, whose role is to drive the drilling tools to rotate for breaking rock formations. It includes the rotary table, swivel, and drilling tools. The composition of drilling tools varies depending on the type of well being drilled; generally, it includes the kelly, drill pipe, drill collars, and drill bit, as well as stabilizers, shock absorbers, and adapter subs. Among them, the drill bit is the tool that directly breaks rock. Drill collars have high weight and wall thickness, used to apply WOB to the drill bit. Drill pipes connect surface equipment and downhole equipment and transmit torque. The kelly typically has a square cross-section; the rotary table drives the entire drill string and drill bit to rotate via the kelly. The swivel is a typical component of a rotary drilling rig: it not only bears the weight of the drilling tools but also enables rotational movement, while providing a channel for high-pressure mud. Ⅲ. Circulation System The rotary drilling rig is equipped with a circulation system to promptly carry cuttings broken by the downhole drill bit to the surface for continuous drilling, while cooling the drill bit, protecting the wellbore, and preventing drilling accidents such as wellbore collapse and lost circulation. The circulation system includes mud pumps, surface manifolds, mud tanks, and mud purification equipment. The surface manifolds include high-pressure manifolds, standpipes, and hose lines; the mud purification equipment includes shale shakers, desanders, desilters, and drilling mud centrifuges. The mud pump suctions mud from the mud tank; the mud, after being pressurized by the mud pump, flows through the high-pressure manifold, standpipe, and hose line, enters the swivel, and is lowered to the bottom of the well through the hollow drilling tools. It is ejected from the nozzles of the drill bit, then carries cuttings back to the surface through the annular space between the wellbore and the drilling tools. The mud returned from the bottom of the well passes through various levels of mud purification equipment to remove solid content, and then is reused. Ⅳ. Power Equipment The hoisting system, circulation system, and rotary system are the three major working units of the drilling rig, used to provide power. Their coordinated operation enables drilling operations. To supply power to these working units, the drilling rig needs to be equipped with power equipment. The power equipment of a drilling rig includes diesel engines, AC motors, and DC motors. Ⅴ. Transmission System The transmission system converts the force and motion provided by the power equipment, then transmits and distributes them to each working unit to meet the different power requirements of each unit. The transmission system generally includes a reduction mechanism, speed change mechanism, forward/reverse mechanism, and a coupling mechanism between multiple power machines. Ⅵ. Control System To ensure the coordinated operation of the three major working units of the drilling rig and meet the requirements of drilling technology, the drilling rig is equipped with a control system. Control methods include mechanical control, pneumatic control, electrical control, and hydraulic control. The commonly used control method on drilling rigs is centralized pneumatic control. The driller can complete almost all drilling rig controls through the driller's console on the rig, such as engaging/disengaging the main clutch; coupling multiple power machines; starting/stopping the drawworks, rotary table, and mud pumps; and controlling the high/low speed of the drawworks. Ⅶ. Derrick and Substructure The derrick and substructure are used to support and install various drilling equipment and tools, and provide a drilling operation site. The derrick is used to install the crown block, suspend the traveling block, hook, swivel, and drilling tools, bear drilling workloads, and stack stands. The substructure is used to install the power unit, drawworks, and rotary table, support the derrick, suspend the drilling tools via the rotary table, and provide height space between the rotary table and the ground for installing necessary BOPs and facilitating mud circulation. Ⅷ. Auxiliary Equipment To ensure the safety and normal progress of drilling, the drilling rig also includes other auxiliary equipment, such as a BOP stack for preventing blowouts, a generator set for providing lighting and auxiliary power for drilling, an air compression device for supplying compressed air, and water supply and oil supply equipment.  

The hoisting system in oil drilling is a crucial component of oil drilling equipment, mainly used for tripping drill strings and casings, as well as suspending drill strings during drilling operations. The following are some of the main equipment in this system: Ⅰ. DerrickStructural Features: The derrick is a large-scale steel structure, usually including types such as the tower-shaped derrick, A-shaped derrick, and mast derrick. The tower-shaped derrick has an overall tower-like structure, with high stability and load-bearing capacity, capable of withstanding large loads. However, it is large in size, heavy in weight, and relatively complex in disassembly, assembly, and transportation. The A-shaped derrick is composed of two inclined brackets and a top crossbeam, resembling the letter "A" in shape. It has a compact structure, is convenient for disassembly and assembly, and is widely applied. The mast derrick is relatively low and has a small footprint, suitable for places with limited space.Function: The derrick provides support and fixation for the entire hoisting system. Through its steel structure framework, it bears the weights of equipment such as the crown block, traveling block, and drill string, as well as various tensile forces and pressures generated during the hoisting process. It enables the drill string to be raised and lowered vertically, and provides installation positions for hoisting equipment and tools such as the crown block, traveling block, rotary swivel, (top drive) power tongs, and elevator. It also ensures that operators have sufficient space for drilling operations. Ⅱ. Crown Block Structural Composition: Installed at the top of the derrick, it is a fixed sheave block composed of multiple sheaves.The crown block sheaves are usually made of high-quality steel, with high wear resistance and strength to withstand the huge tensile forces generated by frequent hoisting and lowering operations.Function: It changes the direction of the wire rope, transmits the pulling force of the drawworks to the traveling block, and realizes the hoisting and lowering of the drill string. Through the combination of multiple sheaves, it can effectively distribute the pulling force, reduce the load borne by a single sheave, and improve the reliability and safety of the system. Ⅲ. Traveling BlockStructural Features: Connected to the crown block by a wire rope, it is a movable sheave block, usually composed of multiple sheaves, which cooperates with the sheave block of the crown block through the wire rope to form a labor-saving hoisting system. The number and size of the sheaves are determined according to the load-bearing capacity of the traveling block and the requirements of the drilling operation. The lower part of the traveling block is connected to the drill string through the traveling block hook. Under the action of the hoisting system, it drives the drill string to move up and down. The structural design of the traveling block should ensure its flexibility and stability during movement, and it should be able to withstand the weight of the drill string and the impact force during the hoisting process.Function: Driven by the drawworks, it moves the drill string up and down through the pulling of the wire rope. Since the traveling block is a movable sheave block, according to the principle of labor-saving of the sheave block, it can amplify the pulling force of the drawworks, enabling the hoisting of heavier drill strings. Ⅳ. HookStructural Composition: The hook is connected below the traveling block, suspending the drill string through the hook body, and forms a hoisting system together with the traveling block, crown block, and drawworks. The hook has a rotatable hook body and a safety locking device.Function: Its working principle is relatively simple. It mainly uses its own structural features and connection devices to transmit the pulling force of the traveling block to the drill string, facilitating the connection and separation with the joint of the drill string, and preventing the drill string from accidentally falling off during the hoisting process. The rotating function of the hook body allows the drill string to rotate as needed during the hoisting and lowering process. For example, when connecting or disassembling drill pipes, it enables the threads of the drill pipes to be accurately aligned. The safety locking device of the hook prevents the hook body from accidentally opening after the drill string is suspended, ensuring that the drill string will not fall off and guaranteeing the safety of the operation. The load-bearing capacity of the hook varies according to the depth of the well and the weight of the drill string, generally ranging from several dozen tons to several hundred tons. Ⅴ. DrawworksThe drilling drawworks is not only the main equipment of the hoisting system but also the core part of the entire drilling and workover rig, and it is one of the three major working units of the drilling and workover rig. A classic three-axis electric-driven drilling rig.Structural Features: As the power equipment of the hoisting system and the power source, it is usually driven by an electric motor or a diesel engine. The drawworks contains components such as a transmission device, a drum, and a braking system.Function: It controls the lifting speed and position of the traveling block and the drill string by winding and unwinding the wire rope. The transmission device can transmit power to the drum at different rotation speeds and torques according to different operation requirements. When the drill string needs to be hoisted, the drum rotates forward and winds the wire rope, thus pulling the traveling block and the connected drill string upward; when lowering the drill string, the drum rotates in reverse and releases the wire rope, and the drill string slowly descends under its own gravity. The braking system uses components such as brake pads or brake discs to quickly stop the rotation of the drum when necessary, making the drill string stop at the specified position and achieving the hovering function, ensuring the safety and precise control of the operation. Ⅵ. Wire RopeStructural Features: Made of high-strength and corrosion-resistant steel, it has high breaking tensile force and good flexibility. Generally, it is twisted by multiple strands of steel wires, and the outer layer may also have a protective layer to improve its wear resistance and corrosion resistance. In order to ensure the service life and safety of the wire rope, it is necessary to regularly inspect, lubricate, and replace it. When selecting a wire rope, an appropriate one should be determined according to factors such as the depth of the well and the load.Function: It connects the crown block, traveling block, and drawworks, transmits the pulling force, and suspends the drill string. During the drilling process, the wire rope needs to bear a huge pulling force, so its quality and performance directly affect the safety and reliability of the hoisting system. The wire rope bypasses multiple sheaves of the crown block and traveling block to form a multi-strand rope system. According to the principle of labor-saving of the sheave block, in this way, the drawworks only needs to provide a pulling force smaller than the gravity of the drill string to achieve the hoisting of the drill string. For example, a crown block and traveling block system composed of multiple sheaves can amplify the pulling force of the drawworks several times, enabling the hoisting of drill strings weighing dozens of tons or even hundreds of tons. At the same time, the sheave block can also change the direction of the force, allowing the drawworks to be operated in a more convenient position while the drill string can be raised and lowered vertically. In addition, the oil drilling hoisting system may also include some auxiliary equipment, such as the anti-collision device for preventing the traveling block from rising too high and colliding with the crown block, and the dead rope anchor for fixing one end of the wire rope. These devices work together to ensure that the oil drilling hoisting system can operate safely and efficiently, and complete the operations such as tripping drill strings and casings during the oil drilling process.