Operation method for prolonging service life of main hoisting steel wire rope of metallurgical crane

Abstract

The invention discloses an operation method for prolonging the service life of a main hoisting steel wire rope of a metallurgical crane, and belongs to the technical field of metallurgical cranes. The following technical scheme is adopted: operation protection adopts a six-step method of'slow, stop, watching, listening, correction and confirmation '; the steel wire rope is maintained by using a device in which a steel wire rope reel drives a refueling pump through an electric coupling 8 and automatically sprays lubricating oil through a reel branch pipe nozzle and a pulley branch pipe nozzle; pulley maintenance adopts a method that a pulley clamping row clings to a pulley rope groove amplitude and clay is filled to measure the abrasion loss of the rope groove, and measurement and replacement are performed every half a year; the steel wire rope protection comprises anti-impact protection when the constraint operation time of a PLC control system is longer than or equal to 2S and stress protection when a steel wire rope tensiometer monitors abnormal tension in real time; the diameter of the steel wire rope is measured in three time periods, and inspection is carried out in three levels. Through combined implementation of the necessary technical characteristics, the service life of the main hoisting steel wire rope is prolonged, the equipment maintenance cost is remarkably reduced, and the production continuity is improved.

Description

Technical Field

[0001] This invention belongs to the field of metallurgical crane technology, specifically relating to an operation method for extending the service life of the main hoisting wire rope of a metallurgical crane. Background Technology

[0002] Currently, in the steelmaking process of the metallurgical industry, molten iron and steel converters are transported using metallurgical casting cranes. Lifting molten iron and steel involves high-temperature, heavy-load, and high-risk operations. In particular, damage to the main hoisting wire ropes of these cranes is affected by factors such as high-temperature baking and heat radiation corrosion, damage from molten slag splashes, heavy loads and impact loads, friction and wear between the wire rope and pulleys, inadequate daily maintenance, and improper operation. Among these, pulley wear, inadequate daily lubrication and maintenance, and improper operation are the main causes of wire rope damage, significantly reducing their lifespan. To ensure safe lifting of molten metal, the service life of wire ropes for cranes used in the steelmaking industry is mostly one year or less. Especially given the current trend of reduced production in the steel industry and low profit margins on steel purchases and sales, the short service life of wire ropes has a significant impact on cost control, which is inconsistent with the current development strategy of cost reduction and efficiency improvement in the steel industry.

[0003] Under the aforementioned high-temperature, heavy-load, and high-risk operating conditions, the main hoisting wire rope of the crane is continuously subjected to multiple factors, including high-temperature baking and heat radiation erosion, damage from molten slag splashes, heavy loads and impact loads, friction and wear between the wire rope and pulleys, inadequate daily maintenance, and improper operation. Among these, pulley damage and wear directly exacerbate localized wear of the wire rope, inadequate daily lubrication and maintenance lead to accelerated wear due to lack of oil, and improper operation further causes additional damage to the wire rope. All these factors combined significantly reduce the lifespan of the wire rope. To ensure the safe lifting of molten metal, the actual service life of wire ropes for cranes lifting molten iron and steel in the steelmaking industry is mostly only one year or less. Especially under the current circumstances of reduced production in the steel industry and low profit margins on steel purchases and sales, the short service life of wire ropes directly impacts cost control, which is inconsistent with the steel industry's development strategy of cost reduction and efficiency improvement, and minimizing costs.

[0004] In existing hoisting operations, improper operation can easily lead to excessively fast lifting and lowering speeds or sudden starts and stops, causing the wire rope to bear additional impact loads. During hoisting, the molten steel ladle may not remain stable, resulting in swaying or tilting, causing uneven stress on the wire rope. Improper oblique pulling or lifting causes the wire rope to bear lateral forces, exacerbating localized wear and fatigue. Inadequate maintenance further amplifies these damages; pulley wear and lubrication deficiencies cannot be detected and corrected in a timely manner, leading to frequent wire rope failures. These persistent problems result in frequent wire rope replacements, increasing equipment maintenance costs, reducing production continuity, and placing significant economic pressure on enterprises. Therefore, there is an urgent need for an operational method that can systematically optimize the operation to address the specific damage factors mentioned above, in order to extend the service life of the main hoisting wire rope and reduce overall maintenance costs. Summary of the Invention

[0005] In view of this, the purpose of the present invention is to solve the above problems and provide an operating method for extending the service life of the main hoisting wire rope of a metallurgical crane.

[0006] To achieve the above objectives, the present invention provides the following technical solution: A method for extending the service life of the main hoisting wire rope of a metallurgical crane includes the following steps: Operation and safety procedures: The crane operation is controlled using a six-step method: "slow down, stop, look, listen, correct, and confirm" on the work interface. Wire rope maintenance steps: Use an automatic wire rope lubrication device to spray lubricating oil onto the drum and pulley block by driving the lubrication pump through the main hoisting drum to achieve automatic and continuous lubrication; Pulley maintenance steps: Use the pulley groove wall thickness measurement method to measure the wear of the pulley groove every six months, and replace the pulley in time when it reaches the scrap standard; Wire rope protection steps include impact protection and stress protection. The crane's PLC control system is used to constrain the operation time and monitor abnormal tension to prevent damage to the wire rope from impact and abnormal tension. The procedure for measuring the diameter of a wire rope is as follows: the diameter is measured in three time periods to assess the wear of the wire rope. Wire rope inspection steps: The inspection is carried out in three levels to promptly detect defects such as broken wires, broken strands, lubrication issues, corrosion, and deformation.

[0007] Furthermore, in the aforementioned operational protection steps, the work interface point is defined as approximately 1 meter in front, behind, left, right, and above the suspended object or work position when the hook is empty or the object is being lifted; the work within the work interface point must be carried out under the continuous command of a designated person and must be intermittent, and must not be completed in one go; "slow" means decelerating when approaching the work interface point and operating in first gear within the interface point; "stop" means stopping the hook at the interface point; "look" means confirming that the commanding person has command markings, confirming that the commanding person's position is safe, and clearly seeing the commanding person's hand gestures; "listen" means obeying the correct command of the commanding person and clearly hearing the whistle or walkie-talkie instructions; "correct" means correcting the position of the trolley and crane to prevent the suspended object from swinging and hitting personnel or equipment; "confirm" means that the ground personnel are in a safe position, the suspended object is reliably suspended, and the brake is flexible and reliable.

[0008] Furthermore, the automatic wire rope lubrication device used in the wire rope maintenance process includes an oil tank, an oil outlet pipe installed on the oil tank, an oil inlet control valve on the oil outlet pipe, a lubrication pump driven by the main hoisting wire rope drum through an electric coupling, an oil outlet control valve on the oil outlet pipe, two or more branch oil outlet pipes branching off from the oil outlet control valve, a regulating valve installed at the inlet of each branch pipe, a branch pipe valve on the branch pipe from the branch pipe to the main hoisting drum or pulley, and a branch pipe nozzle after the branch pipe valve; the branch pipe nozzle is located above the main hoisting drum and pulley assembly; the power connection between the drum and the lubrication pump, and the positional relationship of the nozzle above the drum and pulley assembly, enable automatic and continuous lubrication.

[0009] Furthermore, the method for measuring the wall thickness of the pulley rope groove used in the pulley maintenance steps employs a measuring ruler. Before each pulley is put into use, a measurement position mark is marked on the pulley. A measuring mold is made using clay to completely fit the inner side of the pulley rope groove at the measurement position, and a measuring ruler is made according to the mold size. During measurement, the oil stains at the measurement position mark are cleaned, the outer clip of the measuring ruler is tightly attached to the outer side of the pulley rope groove, and the gap between the measuring ruler and the pulley rope groove is filled with clay. After removal, a vernier caliper is used to measure the thickness of the clay inside the pulley rope groove as the wear amount. When the wear standard is reached, the pulley is replaced in time. The fit between the measuring ruler and the rope groove and the clay filling relationship ensure accurate measurement of the wear amount.

[0010] Furthermore, the anti-impact protection in the wire rope protection step utilizes the crane PLC control system to add anti-impact protection settings for the wire rope. The main hoisting master controller is set to operate from 0 to 4 or from 4 to 0 in a time ≥ 2 seconds. When the operation time is detected to be < 2 seconds, the audible and visual alarm in the control room will sound an alarm. The signal connection between the PLC program and the master controller enables the forced constraint of the operation speed.

[0011] Furthermore, the force protection in the wire rope protection step uses a wire rope tension protection system, which includes a crane PLC control system, a wire rope tension meter, and a wire rope tension receiver. The wire rope tension meter is installed on the fixed section of the wire rope of the main hoisting hook balance arm, and the tension meter sends the tension value to the PLC in real time. The installation position of the tension meter on the fixed section of the balance arm and its signal connection with the PLC enable immediate protection against tension abnormalities.

[0012] Furthermore, the wire rope diameter measurement process is divided into three time periods: the first time period is after the wire rope has been in use for 6 months; the second time period is during the period of 7-12 months, with measurements taken every 2 months for a total of 3 times; and the third time period is after more than 12 months, with measurements taken every 7 days. When the tension in the wire rope exceeds the tension value set by the tension gauge, the PLC system sends an alarm signal to the audible and visual alarm and a control signal to the main hoisting motor to stop the lifting of the load. At this time, only the lowering action can be performed. When the tension in the wire rope is lower than the tension value set by the tension gauge, the PLC system sends an alarm signal to the audible and visual alarm and a control signal to the main hoisting motor to stop the lifting. The signal control relationship between the PLC and the motor realizes the immediate protection action for abnormal tension.

[0013] Furthermore, the wire rope inspection process is divided into three levels: Crane operators must inspect for broken wires, broken strands, lubrication issues, corrosion, and deformation every shift. Equipment inspectors check for broken wires, broken strands, lubrication, corrosion, deformation, shape, and diameter measurements weekly. Equipment technicians conduct precision inspections.

[0014] Furthermore, the oil pump rotating shaft of the automatic wire rope oiling device is connected to the main hoisting drum via an electric coupling. When the main hoisting drum rotates, it drives the oil pump to run and sprays lubricating oil onto the wire rope through the nozzle. When the device is not running, the coupling is electrically removed to disconnect the oil pump from the drum. The power transmission relationship between the drum, coupling, and oil pump realizes automatic lubrication of the drum drive.

[0015] Furthermore, the oil outlet control valve of the automatic wire rope oiling device is divided into two or more oil outlet branch pipes. Each branch pipe inlet is equipped with a regulating valve to control the oil volume of each branch pipe. A switch valve is installed on the branch pipe leading to the drum or pulley. The connection relationship between the branch pipe regulating valve and the branch pipe valve enables independent adjustment of the oil volume of each branch.

[0016] The beneficial effects of this invention are as follows: This invention significantly extends the service life of the main hoisting wire rope of a metallurgical crane through the above-described operating method. The service life of the main hoisting wire rope is extended from the original 12 months to a minimum of 15 months and a maximum of 18 months. At the same time, it reduces equipment maintenance costs, improves production continuity, and helps enterprises reduce costs and increase efficiency.

[0017] Specifically, the operational safety procedures employ a six-step method: "Slow down, stop, look, listen, correct, and confirm." This method prevents crane operators from using excessive speed or sudden starts and stops during lifting and lowering, which could cause additional impact loads on the wire rope. It also prevents uneven stress on the wire rope caused by swaying or tilting of the molten steel ladle during hoisting, and avoids improper oblique pulling or lifting, which could exacerbate localized wear and fatigue due to lateral forces. The wire rope maintenance procedure utilizes an automatic lubrication device. The main hoisting drum drives a lubrication pump to continuously spray lubricating oil onto the drum and pulley block, ensuring adequate lubrication of the wire rope and preventing rapid wear due to insufficient oil. The pulley maintenance procedure involves measuring the wear of the pulley grooves every six months and promptly replacing pulleys that have reached the end of their service life to prevent damage to the wire rope due to pulley breakage. The impact protection in the wire rope protection process utilizes a PLC control system to constrain the operation time to ≥2 seconds, preventing rapid human operation that could increase impact damage. Stress protection is achieved through real-time monitoring with a tension gauge; when the tension exceeds or falls below the set value, the PLC alarms and controls the motor to stop abnormal lifting, effectively preventing damage to the wire rope from overload or wire rope slack. The wire rope diameter measurement process is conducted in three time periods, and the wire rope inspection process is conducted at three levels to further understand the wear condition and promptly detect problems such as broken wires, broken strands, corrosion, and deformation.

[0018] Other advantages, objectives, and features of the invention will be set forth in part in the description which follows, and in part will be apparent to those skilled in the art from the following examination, or may be learned from practice of the invention. The objectives and other advantages of the invention can be realized and obtained through the following description. Attached Figure Description

[0019] To make the objectives, technical solutions, and advantages of the present invention clearer, the preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings, wherein: Figure 1 This is a schematic diagram of the pulley rope groove wall thickness measuring device in this invention.

[0020] Figure 2 This is a schematic diagram of the automatic wire rope lubrication device of the present invention.

[0021] Figure 3 This is a schematic diagram of the wire rope tension protection system in this invention.

[0022] Attached reference numerals: 1-Pulley clamp; 2-Pulley rope groove width; 3-Oil tank; 4-Inlet oil pipe control valve; 5-Oil pump; 6-Branch pipe regulating valve; 7-Outlet oil pipe control valve; 8-Electric coupling; 9-Drum branch pipe valve; 10-Drum branch pipe nozzle; 11-Wire rope drum; 12-Wire rope; 13-Pulley branch pipe valve; 14-Pulley branch pipe nozzle; 15-Pulley block; 16-Crane PLC control system; 17-Crane lifting and lowering controller; 18-Crane lifting speed sensor; 19-Wire rope tension meter; 20-Crane hook balancer; 21-Wire rope tension receiver; 22-Audible and visual alarm.

[0023] The oil outlet pipe installed on the oil tank, the oil inlet pipe control valve on the oil outlet pipe, the oil pump driven by the main hoisting wire rope drum through an electric coupling, the oil outlet pipe control valve on the oil outlet pipe, two or more oil outlet branch pipes branching off after the oil outlet pipe control valve, the regulating valve installed at the inlet of each branch pipe, the branch pipe valve on the branch pipe from the branch pipe to the main hoisting drum or pulley, and the branch pipe nozzle after the branch pipe valve; Detailed Implementation The following specific examples illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and various details in this specification can be modified or changed based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the illustrations provided in the following embodiments are only schematic representations of the basic concept of the present invention. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0024] The accompanying drawings are for illustrative purposes only and are schematic diagrams, not actual pictures. They should not be construed as limiting the invention. To better illustrate the embodiments of the invention, some parts in the drawings may be omitted, enlarged, or reduced, and do not represent the actual product dimensions. It is understandable to those skilled in the art that some well-known structures and their descriptions may be omitted in the drawings.

[0025] In the accompanying drawings of the embodiments of the present invention, the same or similar reference numerals correspond to the same or similar components. In the description of the present invention, it should be understood that if terms such as "upper," "lower," "left," "right," "front," and "rear" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, they are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the terms used to describe positional relationships in the drawings are only for illustrative purposes and should not be construed as limiting the present invention. For those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances.

[0026] Example 1 like Figures 1-3 The image shows an operating method for extending the service life of the main hoisting wire rope of a metallurgical crane, including operating safety procedures and wire rope maintenance procedures (such as an automatic wire rope lubrication device). Figure 2 As shown), pulley maintenance procedures (pulley rope groove wall thickness measurement method and device, such as...) Figure 1 (As shown), wire rope protection steps (wire rope tension protection system, such as...) Figure 3 (As shown), the steps for measuring the diameter of the wire rope and the steps for inspecting the wire rope.

[0027] Automatic wire rope lubrication device (such as...) Figure 2 (As shown) includes an oil tank 3, an oil outlet pipe installed on the oil tank 3, an oil inlet pipe control valve 4 on the oil outlet pipe, an oil pump 5 driven by a wire rope drum 11 through an electric coupling 8, an oil outlet pipe control valve 7 on the oil outlet pipe, two or more oil outlet branch pipes branching off after the oil outlet pipe control valve 7, a branch pipe regulating valve 6 installed at the inlet of each branch pipe, a drum branch pipe valve 9 from the branch pipe to the wire rope drum 11, a drum branch pipe nozzle 10 after the drum branch pipe valve 9, a pulley branch pipe valve 13 from the branch pipe to the pulley block 15, and a pulley branch pipe nozzle 14 after the pulley branch pipe valve 13. The drum branch pipe nozzle 10 and pulley branch pipe nozzle 14 are located above the wire rope drum 11 and pulley block 15. The rotating shaft of the oil pump 5 is connected to the wire rope drum 11 through an electric coupling 8. When the wire rope drum 11 rotates, it drives the oil pump 5 to run and sprays lubricating oil evenly onto the wire rope 12 through the drum branch pipe nozzle 10 and pulley branch pipe nozzle 14. When the device is not running, the electric coupling 8 is electrically removed to disconnect the oil pump 5 from the wire rope drum 11. The connection relationship between the branch pipe regulating valve 6 and the drum branch pipe valve 9 and pulley branch pipe valve 13 enables independent adjustment of the oil volume of each branch.

[0028] Pulley groove wall thickness measuring device (e.g.) Figure 1 (As shown) includes a pulley block 1 and a pulley rope groove width 2; before each pulley is used, a measurement position mark is marked on the pulley, and a measurement mold is made using clay to completely fit the inner side of the pulley rope groove at the measurement position. A measuring ruler is made according to the size of the mold; during measurement, the oil stains at the measurement position mark are cleaned, the pulley block 1 is tightly attached to the outer side of the pulley rope groove width 2 outside the measuring ruler, and the gap between the measuring ruler and the pulley rope groove is filled with clay. After removal, the thickness of the clay inside the pulley rope groove is measured with a vernier caliper as the wear amount.

[0029] Wire rope tension protection system (such as Figure 3(As shown) includes a crane PLC control system 16, a crane lifting and lowering controller 17, a crane lifting speed sensor 18, a wire rope tension meter 19, a crane hook balancer 20, a wire rope tension receiver 21, and an audible and visual alarm 22; the wire rope tension meter 19 is installed on the wire rope fixed section of the crane hook balancer 20, and the wire rope tension meter 19 sends the tension value to the crane PLC control system 16 in real time to the wire rope tension receiver 21.

[0030] When using 350-ton and 360-ton metallurgical cranes to lift molten iron and steel in a steel plant, operators must first follow the operational safety procedures, adhering to the "slow, stop, look, listen, correct, confirm" six-step method for the work interface: The work interface point is defined as approximately 1 meter in front, behind, left, right, and above the load or work position when the hook is empty or the load is being lifted. Within this point, operators must follow the instructions of a designated person throughout the entire process, with intermittent commands. "Slow" means slowing down as you approach the work interface point and operating in first gear within that point. "Stop" means stopping the hook at the interface point. "Look" means confirming that the commanding personnel have markings, that their position is safe, and that their hand gestures are clearly visible. "Listen" means obeying the correct commands from the commanding personnel and clearly hearing whistles or walkie-talkie instructions. "Correct" means correcting the position of the trolley and crane to prevent the load from swinging and impacting personnel or equipment. "Confirm" means ensuring the safety of ground personnel, reliable load attachment, and flexible and reliable brake operation. After the wire rope maintenance procedure is started, the wire rope drum 11 rotates, driving the oil pump 5 through the electric coupling 8. The lubricating oil is sent to the drum branch pipe nozzle 10 and the pulley branch pipe nozzle 14 through the oil outlet pipe control valve 7, the branch pipe regulating valve 6, the drum branch pipe valve 9, and the pulley branch pipe valve 13, respectively, to continuously spray lubricating oil onto the wire rope 12 above the wire rope drum 11 and the pulley block 15, so as to achieve automatic and continuous lubrication.

[0031] The pulley maintenance procedure should be performed every six months: After cleaning the oil stains at the measuring position mark, use the pulley clip 1 to tightly fit the outside of the pulley rope groove 2, fill the gap with clay, and use a vernier caliper to measure the thickness of the clay as the wear amount. Replace the pulley in time when it reaches the scrap standard. In the wire rope protection process, the impact protection is monitored by the crane PLC control system 16 through the crane lifting controller 17 and the crane lifting speed sensor 18. When the operation time of the crane lifting controller 17 from 0 to 4 or from 4 to 0 is less than 2 seconds, the audible and visual alarm 22 sounds an alarm. The force protection is monitored in real time by the wire rope tension meter 19. When the force on the wire rope exceeds the tension value set by the wire rope tension meter 19, the crane PLC control system 16 sends an alarm signal to the audible and visual alarm 22 and sends a control signal to the main lifting motor to stop the lifting of the load. At this time, only the lowering action can be performed. When the force on the wire rope is lower than the tension value set by the wire rope tension meter 19, the crane PLC control system 16 sends an alarm signal to the audible and visual alarm 22 and sends a control signal to the main lifting motor to stop the lifting.

[0032] The wire rope diameter measurement process is divided into three periods: the first period is after the wire rope has been in use for 6 months; the second period is from 7 to 12 months, measured every 2 months for a total of 3 times; the third period is after 12 months, measured every 7 days. The wire rope inspection process is divided into three levels: crane operators check for broken wires, broken strands, lubrication, corrosion, and deformation every shift; equipment inspectors check for broken wires, broken strands, lubrication, corrosion, deformation, shape, and diameter measurement weekly; and equipment technicians perform precision inspections.

[0033] When a metallurgical crane is lifting molten iron or steel, the operator starts the crane and performs the above six-step operation control. At the same time, the automatic wire rope lubrication device starts automatically as the wire rope drum 11 rotates and provides continuous lubrication. The pulley groove wall thickness measuring device is accurately measured and replaced every six months. The wire rope tension protection system monitors in real time.

[0034] When the operator suddenly starts or stops the crane, causing the crane lifting controller 17 to operate for less than 2 seconds, the crane lifting speed sensor 18 sends a signal to the crane PLC control system 16, and the audible and visual alarm 22 immediately sounds an alarm, forcibly restricting the operating speed.

[0035] When the ladle is overloaded or the wire rope is slack, causing abnormal tension, the wire rope tension meter 19 sends the signal to the crane PLC control system 16 in real time through the wire rope tension receiver 21. The audible and visual alarm 22 alarms and controls the main hoisting motor to stop hoisting, allowing only descent. The system will resume operation after the abnormality is eliminated.

[0036] By implementing the aforementioned necessary technical features, the service life of the main hoisting wire ropes for the 350-ton and 360-ton cranes at Chongqing Iron and Steel Plant has been extended from the original 12 months to a minimum of 15 months, with the longest service life reaching 18 months. Before implementation, the annual cost was: 155.885 × 395 × 4 + 121.77 × (395 × 8 + 435 × 4 + 365 × 8) = 1,198,500 yuan / year; after implementation, the annual cost was: 1,198,500 - 1,198,500 × 0.25 = 898,875 yuan / year; the economic benefit was: 1,198,500 - 898,875 = 299,625 yuan / year.

[0037] The above process requires no additional manual intervention. Automatic lubrication, precise wear monitoring, and real-time tension protection are achieved solely through the drive of the wire rope drum 11, the signal connection of the crane PLC control system 16, the fit between the pulley clamp 1 and the pulley rope groove 2, and the measurement relationship of the clay filling. This ensures stable operation of the wire rope under high temperature and heavy load conditions, significantly reduces equipment maintenance costs, and improves production continuity.

[0038] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A method for extending the service life of the main hoisting wire rope of a metallurgical crane, characterized in that, Includes the following steps: Operation and safety procedures: The crane operation is controlled using a six-step method: "slow down, stop, look, listen, correct, and confirm" on the work interface. Wire rope maintenance steps: Use an automatic wire rope lubrication device to spray lubricating oil onto the drum and pulley block by driving the lubrication pump through the main hoisting drum to achieve automatic and continuous lubrication; Pulley maintenance steps: Use the pulley groove wall thickness measurement method to measure the wear of the pulley groove every six months, and replace the pulley in time when it reaches the scrap standard; Wire rope protection steps include impact protection and stress protection. The crane's PLC control system is used to constrain the operation time and monitor abnormal tension to prevent damage to the wire rope from impact and abnormal tension. The procedure for measuring the diameter of a wire rope is as follows: the diameter is measured in three time periods to assess the wear of the wire rope. Wire rope inspection steps: The inspection is carried out in three levels to promptly detect defects such as broken wires, broken strands, lubrication issues, corrosion, and deformation.

2. The operating method according to claim 1, characterized in that, In the aforementioned operational safety procedures, the work interface point is defined as approximately 1 meter in front, behind, left, right, and above the suspended object or work position when the hook is empty or the object is being lifted; the work within the work interface point must be carried out under the continuous command of a designated person and must be intermittent, and must not be completed in one go; "slow" means decelerating when approaching the work interface point and operating in first gear within the interface point; "stop" means stopping the hook at the interface point; "look" means confirming that the commanding person has command markings, confirming that the commanding person's position is safe, and clearly seeing the commanding person's hand gestures; "listen" means obeying the correct command of the commanding person and clearly hearing the whistle or walkie-talkie instructions; "correct" means correcting the position of the trolley and crane to prevent the suspended object from swinging and hitting personnel or equipment; "confirm" means that the ground personnel are in a safe position, the suspended object is reliably suspended, and the brake is flexible and reliable.

3. The operating method according to claim 1, characterized in that, The automatic wire rope lubrication device used in the wire rope maintenance process includes an oil tank, an oil outlet pipe installed on the oil tank, an oil inlet control valve on the oil outlet pipe, a lubrication pump driven by the main hoisting wire rope drum through an electric coupling, an oil outlet control valve on the oil outlet pipe, two or more branch oil outlet pipes branching off from the oil outlet control valve, a regulating valve installed at the inlet of each branch pipe, a branch pipe valve on the branch pipe from the branch pipe to the main hoisting drum or pulley, and a branch pipe nozzle after the branch pipe valve; the branch pipe nozzle is located above the main hoisting drum and pulley assembly; the power connection between the drum and the lubrication pump, and the positional relationship of the nozzle above the drum and pulley assembly, enable automatic and continuous lubrication.

4. The operating method according to claim 1, characterized in that, The pulley rope groove wall thickness measurement method used in the pulley maintenance steps employs a measuring ruler. Before each pulley is put into use, measurement position marks are marked on the pulley. A measuring mold is made using clay to completely fit the inner side of the pulley rope groove at the measurement position, and a measuring ruler is made according to the mold size. During measurement, oil stains are cleaned from the measurement position marks, the outer clip of the measuring ruler is tightly attached to the outer side of the pulley rope groove, and the gap between the measuring ruler and the pulley rope groove is filled with clay. After removal, the thickness of the clay inside the pulley rope groove is measured with a vernier caliper as the wear amount. When the wear standard is reached, the pulley is replaced in time. The fit between the measuring ruler and the rope groove and the clay filling relationship ensure accurate measurement of the wear amount.

5. The operating method according to claim 1, characterized in that, The anti-impact protection in the wire rope protection step utilizes the crane PLC control system to add anti-impact protection settings for the wire rope. The main hoisting master controller is set to operate from 0 to 4 gear or from 4 gear to 0 gear in a time ≥ 2 seconds. When the operation time is detected to be < 2 seconds, the audible and visual alarm in the control room will sound an alarm. The signal connection between the PLC program and the master controller realizes the forced constraint of the operation speed.

6. The operating method according to claim 1, characterized in that, The force protection in the wire rope protection step uses a wire rope tension protection system, which includes a crane PLC control system, a wire rope tension meter, and a wire rope tension receiver. The wire rope tension meter is installed on the fixed section of the wire rope of the main hoisting hook balance arm. The tension meter sends the tension value to the PLC in real time. The installation position of the tension meter on the fixed section of the balance arm and its signal connection with the PLC enable immediate protection against tension abnormalities.

7. The operating method according to claim 1, characterized in that, The wire rope diameter measurement procedure is divided into three periods: the first period is the measurement after the wire rope has been in use for 6 months; the second period is the measurement every 2 months during the period of 7-12 months, for a total of 3 times; the third period is the measurement every 7 days after more than 12 months. When the tension in the wire rope exceeds the tension value set by the tension gauge, the PLC system sends an alarm signal to the audible and visual alarm and a control signal to the main hoisting motor to stop the lifting of the load. At this time, only the lowering action can be performed. When the tension in the wire rope is lower than the tension value set by the tension gauge, the PLC system sends an alarm signal to the audible and visual alarm and a control signal to the main hoisting motor to stop the lifting. The signal control relationship between the PLC and the motor realizes the immediate protection action for abnormal tension.

8. The operating method according to claim 1, characterized in that, The wire rope inspection process is divided into three levels: Crane operators must inspect for broken wires, broken strands, lubrication issues, corrosion, and deformation every shift. Equipment inspectors check for broken wires, broken strands, lubrication, corrosion, deformation, shape, and diameter measurements weekly. Equipment technicians conduct precision inspections.

9. The operating method according to claim 3, characterized in that, The oil pump rotating shaft of the automatic wire rope oiling device is connected to the main hoisting drum via an electric coupling. When the main hoisting drum rotates, it drives the oil pump to run and sprays lubricating oil onto the wire rope through the nozzle. When the device is not running, the coupling is electrically removed to disconnect the oil pump from the drum. The power transmission relationship between the drum, coupling, and oil pump realizes automatic lubrication of the drum drive.

10. The operating method according to claim 3, characterized in that, The automatic wire rope oiling device is divided into two or more branch oil outlet pipes after the oil outlet control valve. Each branch pipe inlet is equipped with a regulating valve to control the oil volume of each branch pipe. A switch valve is installed on the branch pipe to the drum or pulley. The connection between the branch pipe regulating valve and the branch pipe valve enables independent adjustment of the oil volume of each branch.

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