High-Risk Lifting Scenarios

Each type of lifting operation in a steel mill harbors a high risk, especially these three scenarios, where the safety requirements for cranes are at their peak.

The most dangerous is the ladle crane (ladle crane) operation.

Heavy billets, ingots transfer is not easy, these loads are often dozens of hundreds of tons, irregular shape, lifting once shaken, tilted, it is easy to collide with the workshop equipment, and even smashed production line, resulting in production stoppages.

There are also multiple cranes working together in the scene, such as a large steel plant steelmaking workshop, there are usually more than one crane running at the same time, track crossing, overlapping the scope of work, the risk of collision is extremely high, a little improper operation may lead to equipment damage.

Consequences of Failure

Any failure of steel mill crane is not a “small problem”, the consequences are often chained.

The most serious is the risk of personnel safety, high temperature, heavy load environment, once the load falls, steel leakage, the operator is difficult to evacuate in a timely manner, very easy to cause casualties.

Secondly, equipment damage, the crane itself is expensive, plus collision to the steelmaking furnace, continuous casting machine and other core production equipment, repair costs can easily be hundreds of thousands or even millions of dollars, and a long maintenance cycle, will seriously affect production.

The most headache is the loss of downtime, steel mills belong to the continuous production industry, a production line downtime for an hour, the loss may be tens of thousands of dollars, the loss of a day's downtime is incalculable, this cost, no one enterprise can easily afford.

Therefore, the safety of steel mill cranes is never “icing on the cake”, but “life preserver”, even if it costs a little more, we must put the safety configuration in place.

Redundancy

Redundancy design, to put it bluntly, is “double insurance”, which is the core principle of steel mill crane safety design, but also to avoid catastrophic failures.

Simply put, it means that key components should be equipped with backup systems, even if one of them fails, the other one can be activated immediately to ensure the normal operation of the crane and avoid serious accidents such as falling loads.

For example, brake, hoisting mechanism, control system, these components directly related to safety, should be redundant design – like our Henan Mine Crane metallurgical cranes, equipped with dual drive, dual electronic control, dual brake, once the first set of failure, the second set of redundant institutions can independently take on the work, to protect the safety bottom line.

Many customers feel that redundant design is a “waste”, but in steel mills, one more set of backups is one more safety, and can avoid a possible catastrophic accident, which is actually very cost-effective.

Reliability Under Extreme Conditions

Therefore, the safety of steel mill cranes, first of all, to ensure the reliability of such extreme environments, the core is three points: high temperature resistance, dust and iron filings, continuous operation.

High temperature resistance, motor, cable, control box should be designed to withstand high temperatures, such as motor with H-class insulation, cable with metallurgical special high-temperature resistant rubber cable, control box to do thermal sealing treatment to avoid high temperature damage to components.

Dust and iron filings is also very critical, crane bearings, gearboxes, electrical components, should be used to seal the structure, the sensor should also do the three anti-coating treatment, to ensure stable operation in a high dust environment, will not cause wear and tear of components due to dust into the short circuit.

Compliance with Standards

There are three core international standards: ISO 4301, which is the global crane safety standard, stipulates the basic safety requirements and classification standards of cranes; FEM A7-A8, mainly for the European market, the safety factor of metallurgical cranes, redundancy design has more stringent requirements; CMAA Class E/F, is the U.S. standard for heavy-duty, continuously operating cranes. CMAA Class E/F, is the American standard for heavy-duty, continuously operating cranes, emphasizing the reliability and safety performance of the equipment.

Dual Braking System

Dual braking system is the most core and non-negotiable safety feature of steel mill cranes, especially ladle crane, which is mandatory and non-negotiable.

It consists of two independent braking systems: the main brake is responsible for braking in daily operations, such as lifting, deceleration and stopping during operation; the safety brake is the “backup insurance”, once the main brake fails, the safety brake will immediately start to hold the drum to prevent the load from falling.

Our Henan Mine Crane's double brake system adopts the normally closed design, which can avoid the expansion of the accident to the greatest extent by braking at power failure and the reaction time is no more than 0.2 seconds.

Don't choose the single brake system to save money, in the steel mill, a brake failure may cause irreparable losses, how to calculate this account is not cost-effective.

Redundant Hoisting Mechanism

Redundant Hoisting Mechanism is the core of redundant design, which is mainly used in heavy lifting scenarios, such as steel ladle and large billet lifting, and can further enhance the reliability of the equipment.

There are two common designs: dual motor drive or dual gearbox system, through the load distribution design, so that two motors or two gearboxes work together to share the load.

In this way, even if one of the motors or one of the gearboxes fails, the other one can temporarily carry the load and land it safely on the ground without the load suddenly falling. Henan Mine Crane's heavy-duty metallurgical cranes are equipped with redundant hoisting mechanisms, and dual encoders are also installed at the reel end to realize the double checking of speed and displacement, which further enhances safety.

Overload Protection System

Overload is one of the most common safety hazards of cranes, especially in steel mills, workers may be in order to catch up with the schedule, illegal overweight lifting, long-term overload will lead to deformation of the crane structure, accelerated wear and tear of the wire rope, and even lead to breakage, load fall.

The role of the overload protection system is to monitor the lifting load in real time, once the rated load is exceeded, it will automatically cut off the power of the hoisting motor, and at the same time, sound and light alarms will be issued to remind the operator to stop the operation to prevent structural damage to the equipment and safety accidents.

Limit Switch System

Limit switch system, is to control the crane operating range of the “safety boundary”, to prevent the crane beyond the prescribed range, collision to the equipment, building or personnel, steel mill cranes must be equipped with a complete limit switch, you cannot do without.

Our Henan Mine Crane limit switches adopt redundant design, each limit has two independent switches, even if one fails, the other can work normally, and also according to the high temperature and dusty environment of the steel mill, the limit switches will be equipped with a protective cover to extend the service life.

Anti-Collision System

For the steel mill workshop with multiple cranes running at the same time, the Anti-Collision System is an indispensable safety configuration, which can effectively avoid the collision between cranes and between cranes and workshop equipment.

This system through ultrasonic or laser sensors, real-time monitoring of the distance between neighboring cranes, as well as the distance between the crane and the workshop columns, equipment, when the distance is less than the safety value, it will automatically issue an early warning, followed by deceleration, and if it continues to be close to, it will be directly stopped to ensure safety.

Our Henan Mine Crane anti-collision system, strong anti-interference ability, can adapt to the steel mill dust, electromagnetic interference environment, but also according to the layout of the workshop, the flexibility to adjust the safety distance, suitable for multiple cranes working together scene, to avoid damage to equipment and shutdown caused by collision.

Emergency Stop System

Emergency stop system is the “last line of defense” to deal with emergencies, the core requirement is to “stop at any time, everywhere can stop”, to ensure that the operator finds danger in any position, can immediately cut off the power of the equipment.

Intelligent Monitoring Systems

With the enhancement of the level of intelligence in steel mills, intelligent monitoring systems (intelligent monitoring systems) has become an important safety feature for modern steel mills cranes, which can realize the transformation from “passive defense” to “active warning”. The system can realize the transformation from “passive defense” to “active warning”.

This system through the high-precision sensor array, real-time monitoring of the crane's 12 types of core parameters, including lifting height, operating speed, load weight, motor temperature, wire rope wear and tear, etc., once abnormal, it will immediately issue an early warning, and at the same time upload the data to the cloud platform.

Managers can use mobile APP or PC to remotely view the crane's operating status, fault information, and can also play back key parameter changes before the accident, providing data support for accident analysis, discovering potential faults in advance and avoiding accidents.

Our Henan Mine Crane's intelligent monitoring system also supports cluster management of multiple cranes, allowing managers to monitor the operating status of multiple devices at the same time, significantly improving management efficiency.

Predictive Maintenance

Predictive maintenance, the core is “find problems in advance, solve problems in advance”, to avoid sudden failure of cranes, reduce downtime, which is particularly important for continuous production of steel mills.

It analyzes the wear and tear of key components, such as wire rope, brake pads, gear box loss, through the equipment operation data collected by the intelligent monitoring system, and judges the remaining life of the components in advance, reminding the management to replace them in time, so as not to wait for the failure of the components to be repaired.

Henan Mine Crane will also equip every piece of equipment with predictive maintenance to help customers reduce maintenance costs and improve equipment reliability.

Remote Operation Systems

The smelting area of a steel mill is characterized by high temperature, high radiation, high dust, and high safety risks for operators working on site, and remote operation systems (ROS) can be a good solution to this problem.

Operators can be away from the dangerous area of the control room, through the remote console or remote control, control the crane to operate, do not have to be close to the high temperature, high radiation area, can protect the safety of the operator, but also does not affect the accuracy of the operation.

Ladle Crane

Ladle crane (ladle crane) is the crane with the highest safety requirements in steel mills, and there is no one of them, because it directly transports molten metal, and any hidden safety problems may cause catastrophic accidents.

Our Henan Mine Cranes are also equipped with anti-splash devices to further enhance operational safety.

Charging Crane

Charging crane (charging crane), mainly used to add raw materials to the steelmaking furnace, the operating environment is also harsh, high temperature, dusty, and charging will be material impact, the crane's safety requirements are also very high.

Its core safety requirements are anti-impact and overload protection: anti-impact design, can withstand the impact of the material when adding material to avoid deformation of the crane structure; overload protection system, can prevent overload caused by adding too much material to avoid equipment damage.

Slab/Billet Handling Crane

Slab/Billet Handling Crane is mainly responsible for the transfer and stacking of billets and ingots, which are heavy and irregular in shape, and easy to sway when lifting, so the requirements for safety mainly focus on anti-sway and durability.

Anti-sway control is a necessary configuration, can effectively reduce the billet, ingot swaying amplitude, to avoid collision equipment; at the same time, the structure of the crane should be durable to adapt to the long-term heavy load, frequent operations, wire rope, hooks and other components should be made of high-strength materials, to extend the service life.

International Standards

The three core international standards have already been mentioned, and here we will talk about them in detail: ISO 4301, the global crane safety standard, provides for the classification of cranes, safety requirements and test methods, applicable to all types of cranes; FEM, the European Crane Manufacturers' Association standard, of which FEM A7-A8 is mainly for metallurgical FEM, is the European Crane Manufacturers Association standard, of which FEM A7-A8 is mainly for metallurgical cranes, with more stringent requirements for safety factor, redundant design, and high temperature resistance; CMAA, is the standard of the Crane Manufacturers Association of the U.S.A. CMAA Class E/F is for heavy-duty, continuously operating cranes, emphasizing the reliability of the equipment and safety performance.

Special Metallurgical Requirements

Steel mill cranes, compared with ordinary industrial cranes, have some special metallurgical requirements, which are the key to ensure the safety of steel mill operations and cannot be ignored.

The first is a higher safety factor, ordinary cranes usually have a safety factor of 3-4 times, while metallurgical cranes, especially cranes lifting molten metal, have a safety factor of more than 5 times, to ensure that they can withstand extreme loads and emergencies.

Next is the mandatory requirement of redundant systems, for cranes lifting molten metal, double braking, redundant hoisting mechanism is a mandatory configuration, do not allow any omission, which is the key to avoid catastrophic accidents.

In addition, targeted environmental protection measures, such as high temperature protection, dust protection, radiation protection, to ensure that the crane can operate stably in the extreme environment of the steel plant, will not be due to environmental factors lead to the failure of the safety devices.

Combined with these years of front-line experience, I summarized a few customers are most likely to step on the safety mistakes, we must avoid when selecting the type, you can avoid a lot of detours, but also to avoid a lot of potential safety hazards.

The most common misconception is to use ordinary cranes instead of metallurgical crane (metallurgical crane). Many customers figure cheap, think ordinary cranes can be used in steel mills with a little transformation, the results cannot be used for a long time, because of high temperatures, heavy loads lead to equipment failure, and even cause safety accidents – ordinary cranes, safety configuration, materials, cannot adapt to the extreme environment of the steel mills, seems to save money, but buried a big hidden danger.

There is also underestimation of the impact of high temperature, think ordinary insulation measures are enough, the result is that the electrical components are baked by the high temperature, control system failure, resulting in crane failure; lack of collision avoidance system, multiple cranes running at the same time, it is easy to collide; there is no perfect maintenance program, the equipment is not maintained for a long time, the gradual failure of the safety devices, and ultimately lead to accidents.

Daily Inspection

Daily inspection of steel mill cranes, although simple, but can find potential hidden dangers in time, to avoid the expansion of the fault, every day before the start, the operator must do these three checks.

First check the brake, check the brake pads are not worn, whether the brake gap is appropriate, manually test the braking effect, to ensure that the brake can work properly; second check the load limiter and load monitoring system, start the equipment, test the system whether the load can be displayed normally, issued by the early warning; and finally check the emergency stop system, press the position of the emergency stop button, to confirm that it can immediately cut off the power of the equipment, the acoustic and visual alarms can work properly. normal work.

These inspections may seem simple, but they can effectively avoid many safety accidents caused by aging and malfunctioning equipment, so be sure to develop the habit of daily inspection.

Periodic Inspection

In addition to daily inspection, periodic inspection is also very important, usually every six months or once a year, focusing on checking the core components of the equipment, to ensure that the equipment long-term stable operation.

Firstly, check the structural integrity, check the main girder, trolley frame has no deformation, weld has no cracks, wire rope has no wear and tear, broken wire, hook has no deformation, cracks; Secondly, check the electrical system, check the cable has no aging, breakage, electrical components have no loosening, overheating, control system has no faults; Lastly, check the mechanical components, check the lubrication of the gear box, the motor's operating status, limit switches, anti-collision system sensitivity. switch, the sensitivity of the anti-collision system.

After regular inspection, we should make records, replace worn and aging parts in time, do maintenance to prolong the service life of the equipment, and ensure that the safety devices are always in good condition.

Higher Safety = Lower Risk

Many customers when purchasing, will be entangled in the initial cost, think the safety configuration of the crane is too expensive, always want to save a little cost. But in steel mills, safety investment and risk are inversely proportional – the more investment, the higher the safety factor, the lower the risk.

Safety configuration of good cranes, the initial cost will indeed be a little higher, but can effectively avoid safety accidents and downtime losses. For example, cranes equipped with double braking, redundant lifting, intelligent monitoring system, although the initial period of more money, but can reduce the probability of failure, to avoid accidents resulting in casualties, equipment damage and downtime losses, in the long run, on the contrary, more cost-effective.

Although the initial investment of our Henan Mine Crane is a little higher than that of small manufacturers, we use high-quality components, complete safety configuration, low maintenance frequency, less replacement of spare parts, which can help customers to reduce long-term operating costs, and this is why many global customers choose us.

Downtime Cost

As mentioned earlier, the downtime cost of steel mills is extremely high, a production line downtime of one hour, the loss may be tens of thousands of dollars, the loss of one day of downtime is even more incalculable, and may even affect the orders and reputation of the enterprise.

The safety failure of the crane is one of the main reasons for steel mill downtime. A safety configuration is not in place of the crane, it is easy to fail, resulting in the entire production line shutdown, bringing huge economic losses.

Therefore, in the selection of steel mill cranes, “safety investment” is not a waste, but the most cost-effective investment – a little more cost, improve the safety configuration, you can avoid huge losses due to downtime, to protect the continuity of production.

✔ Equipped with dual braking system (a must for steel ladle cranes)

✔ With redundant hoisting mechanism (essential for heavy-duty, molten metal lifting)

✔ Adequate high temperature protection (suitable for high temperature environments in steel mills)

✔ Equipped with anti-collision system (necessary for multiple cranes working at the same time)

✔ Installation of load monitoring system (real-time monitoring of load status)

✔ Equipped with standby power supply (to cope with sudden power failure)

✔ With anti-sway control function (necessary for billet and ladle lifting)

What is the most important safety feature?

→ Dual Braking System. Dual Braking System is mandatory for ladle cranes, especially for lifting molten metal, to ensure that the load will not fall if one set of braking system fails, which is the bottom line for the safety of steel plant operations.

Are standard cranes safe for steel mills?

→ Not safe, must use metallurgical crane (metallurgical special cranes). The safety configuration, material and protection measures of ordinary cranes cannot adapt to the high temperature, heavy load and high dust environment of steel mills, and they are prone to failures and safety accidents.

Why is redundancy important?

→ Redundant design prevents catastrophic failures. The key components of steel mill cranes (such as brakes and hoisting mechanisms) are equipped with backup systems, so that even if one of them fails, the other can be activated immediately to avoid serious accidents such as falling loads and damage to the equipment, and to protect the safety bottom line.

With the extreme conditions in steel mills, every lifting operation is a matter of personnel safety, equipment safety and production continuity, and there is no room for error. steel mill overhead crane safety features are never “the more the merrier,” but rather “Configure according to the needs of the indispensable” – double braking, redundant lifting, collision avoidance, high temperature resistance, these core safety features, less one may be buried safety risks.

Henan Mine Crane has been plowing into the field of metallurgical cranes for decades, focusing on the research and development, production and sales of steel mill overhead cranes. They are equipped with a full set of core safety features, which can be adapted to the requirements of different steel mills around the world.