“Last winter, I stayed for half an hour in the unloading workshop of a mining site in Inner Mongolia. I went there in a hurry without wearing a mask. After leaving the workshop, I constantly felt dust in my lungs and coughed for a whole week.” Even now, the project director of Zheda Jingyi still looks distressed when recalling the harsh on-site working conditions.

The workshop features extremely poor visibility of less than 10 meters. Industrial dust drifts down like snow and covers every steel beam. On the hundred-meter-long track, a coal unloading trolley shuttles back and forth, precisely dumping raw coal into different silos. The sensors mounted on the trolley are invisible amid the dense dust, while magnetic markers are neatly arranged in order along the track.

In the past, manual on-site follow-up operation was mandatory for the unloading trolley, yet the heavily dusty environment was virtually uninhabitable for workers.

Now, human presence is no longer required in the workshop. On the monitor screen in the control room, millisecond-accurate real-time data keeps refreshing continuously, clearly indicating the real-time position and moving route of the trolley. The dynamic data displayed on the screen is precisely captured and transmitted by the sensors installed on the trolley and the magnetic markers laid on the track.

“Last winter, I stayed for half an hour in the unloading workshop of a mining site in Inner Mongolia. I went there in a hurry without wearing a mask. After leaving the workshop, I constantly felt dust in my lungs and coughed for a whole week.” Even now, the project director of Zheda Jingyi still looks distressed when recalling the harsh on-site working conditions.

The workshop features extremely poor visibility of less than 10 meters. Industrial dust drifts down like snow and covers every steel beam. On the hundred-meter-long track, a coal unloading trolley shuttles back and forth, precisely dumping raw coal into different silos. The sensors mounted on the trolley are invisible amid the dense dust, while magnetic markers are neatly arranged in order along the track.

In the past, manual on-site follow-up operation was mandatory for the unloading trolley, yet the heavily dusty environment was virtually uninhabitable for workers.

Now, human presence is no longer required in the workshop. On the monitor screen in the control room, millimetre-accurate real-time data keeps refreshing continuously, clearly indicating the real-time position and moving route of the trolley. The dynamic data displayed on the screen is precisely captured and transmitted by the sensors installed on the trolley and the magnetic markers laid on the track.

Figure 1 On-site shot of the unloading trolley in the mining area

This professional positioning system, the MLS100 Ultra-long Stroke Magnetostrictive Absolute Positioning System (hereinafter referred to as the MLS100 Positioning System), is independently developed and manufactured by Hangzhou Zheda Jingyi. With an ultra-long positioning distance of 2.3 kilometers, it has set a new industry record for magnetostrictive displacement measurement.

This groundbreaking technological breakthrough is rooted in Zheda Jingyi’s 30 years of persistent dedication to magnetostrictive technology research and iteration.

Thirty Years of In-depth Technical Cultivation

Zheda Jingyi’s bond with magnetostrictive displacement technology dates back three decades. In the 1990s, the company originated from Laboratory No.128 of Zhejiang University. The research team focused on the study of magnetostrictive materials, striving to translate theoretical research results into practical engineering applications. Capable of converting micro-level precision mechanical motion into electrical signals, magnetostrictive materials serve as the core component of high-end sensors and actuators.

Over the past thirty years, centering on magnetostrictive materials, Zheda Jingyi has developed four product categories covering twenty-five models of magnetostrictive displacement sensors, successfully overcoming technical bottlenecks in high-sensitivity, high-frequency response and ultra-long-stroke displacement measurement.

Boasting micron-level measurement accuracy, Zheda Jingyi’s magnetostrictive sensors have been deployed in production workshops of thousands of enterprises nationwide. They serve in diverse key scenarios, including blast furnaces of Baosteel, gate control of the Three Gorges Project, and turnout positioning of high-speed railways.

These field-proven sensors are the most credible witnesses of Zheda Jingyi’s technological growth over the decades. The extreme high temperature in steel mills tests the material durability; violent impact from construction machinery verifies its dynamic response speed; and extreme cold environments of wind turbine blades inspect its long-term operational reliability.

With tens of thousands of sensors accumulating over hundreds of millions of hours of on-site operation across more than 30 years, Zheda Jingyi has built a comprehensive technical database. It systematically summarizes the changing rules of magnetostrictive signals under varying distances, temperatures, vibrations, dust and humidity conditions, clarifying the fatigue characteristics of waveguide wires, as well as the differentiation mechanism between interference signals and effective measurement signals.

Through continuous field verification and technological iteration, Zheda Jingyi has achieved in-depth mastery and mature optimization of magnetostrictive core technology.

Empowering Traditional Technology with Innovative Thinking

Magnetostrictive technology is not a newly emerging technology, and its working principle is straightforward. A torsion wave is generated on the waveguide wire after power-on with a magnetic ring matched. The precise position data can be calculated by capturing the time difference of wave transmission.

Figure 2 3D diagram of the magnetostrictive effect

With proficient mastery of magnetostrictive technology, Zheda Jingyi once extended the displacement measuring range from zero up to a maximum of 23 meters.

For decades, however, the entire industry has been trapped by an invisible technical bottleneck, with the measuring limit fixed at 23 meters. Similar to a physical ruler that can only measure distances equal to its own length, the performance boundaries of traditional materials seemed insurmountable.

Extending the measuring range from 23 meters to 2.3 kilometers means breaking through a 100-fold technical gap.

Instead of stubbornly tackling the limits of raw materials, Zheda Jingyi adopted an innovative technical approach. Rather than developing an ultra-long “full-range physical ruler”, the company created a tireless “mobile reading terminal”.

Under this innovative solution, a series of magnetic markers are pre-embedded along the track, with each marker serving as an independent absolute position coordinate point. As the MLS100 positioning system travels along the track and passes these markers, it can accurately identify its real-time position at all times.

Magnetostrictive technology is not a newly emerging technology, and its working principle is straightforward. A torsion wave is generated on the waveguide wire after power-on with a magnetic ring matched. The precise position data can be calculated by capturing the time difference of wave transmission.

Figure 3 Neatly arranged magnetic markers installed on the track

The technical concept is simple in essence. The real challenge lies in maintaining consistent high-precision reading and stable data storage under harsh working conditions involving heavy dust, continuous vibration, rainwater erosion and complex industrial interference.

The MLS100 positioning system delivers a perfect practical solution, achieving superior stability and reliability compared with traditional positioning methods.

Proven Reliability in Automated Production Lines

In a real working scenario with multiple trolleys operating on a single track, three coil transport trolleys shuttle continuously along the same rail to deliver cold-rolled annealed steel coils to designated storage positions.

Traditional contact positioning solutions were previously adopted for this application, yet they suffered from prominent drawbacks including severe wear, fragile structure, frequent signal interference and high maintenance costs, creating an urgent demand for a more stable and reliable long-distance positioning system.

Against this backdrop, the MLS100 positioning system was officially put into operation.

Up to now, the system has been running stably for nearly two years, consistently capturing trolley displacement data with precision up to 0.1 millimeters, with zero operational faults recorded throughout the period.

In the industrial sector, “zero failure operation” is no mere rhetorical description, but the highest recognition of product performance and reliability.

Magnetostrictive technology is not a newly emerging technology, and its working principle is straightforward. A torsion wave is generated on the waveguide wire after power-on with a magnetic ring matched. The precise position data can be calculated by capturing the time difference of wave transmission.

Figure 4 Control room for coil transport trolleys

Such exceptional reliability stems from professional redundant design.

The magnetic markers installed on the track do not work independently. Encapsulated as magnetic cassettes and arranged in groups of three or several units, they form a redundant positioning network. The sensor can acquire accurate position data by detecting just one single cassette. When two or more cassettes are detected simultaneously, automatic data redundancy is realized. Even if individual magnetic markers are damaged by impact, the system continues operating normally without halting the production line. Damaged markers trigger early warning prompts, and replacement can be completed without equipment shutdown.

Such reliable application scenarios are being widely implemented on an increasing number of rail-type linear positioning automated production lines.

For intelligent unmanned cranes, sensors and integrated functional modules are mounted on moving trolleys, while magnetic cassettes are fixed on the stiffeners or surfaces of crane I-beams, enabling precise full-stroke positioning for crane operation.

For car dumper equipment, sensors are side-mounted in confined spaces and transmit signals back to the control room via optical fibers, allowing hundred-ton dumpers to complete accurate flipping and unloading operations.

For stacker-reclaimer equipment, the MLS100 positioning system stably records real-time position data even under severe impact and intense vibration conditions.

Cost Efficiency: The Core Advantage of Industrial Application

For any new industrial technology, practicality and cost-effectiveness are the two essential evaluation criteria: whether it works reliably, and whether it brings tangible value.

The MLS100 positioning system’s two-year zero-fault operation has fully proven its superior performance and reliability.

In terms of economic benefits, practical data shows that its one-time installation cost is 30% lower than that of mainstream traditional positioning systems, while the subsequent maintenance cost is reduced by 60%.

The cost advantage originates from streamlined system design. The MLS100 positioning system consists merely of magnetostrictive displacement sensors, signal conversion modules and a set of magnetic markers, with no complicated wiring layout. Replacing a damaged magnetic marker is as simple as replacing a battery. In contrast, traditional measurement solutions often require full production line shutdown for partial damage, resulting in immeasurable economic losses per maintenance event.

Additionally, its non-contact measurement principle eliminates mechanical wear, greatly extending the overall service life of equipment.

Furthermore, empowered by over 30 years of industry experience serving steel, coal and port sectors, Zheda Jingyi precisely grasps actual on-site demands. The company abandons flashy but impractical functions, and delivers tailored solutions that are fully functional, highly reliable and cost-effective for industrial scenarios.

Back to the mining site in Inner Mongolia: workers no longer need to follow unloading trolleys for on-site operations. Instead, they work in a clean and comfortable control room, monitoring real-time dynamic data on screens and working in a relaxed environment.

Similarly, workers in steel plants are freed from operational troubles caused by inaccurate trolley positioning.

The newly deployed system attracts little attention visually. It emits no light and no sound, acting like a silent guardian on the production line.

Yet everyone on site knows that amid dense industrial dust and orderly running tracks, this system continuously, accurately and persistently outputs precise position data — recording real-time locations, operating distances and subsequent movement trajectories.

Silent as it is, Zheda Jingyi has devoted three decades to polishing magnetostrictive technology. The company faithfully guards every precise measurement scale of China’s industrial manufacturing.

These tiny micron-level scales ultimately span the extraordinary journey from Made in China to Intelligent Manufacturing in China.

Magnetostrictive technology is not a newly emerging technology, and its working principle is straightforward. A torsion wave is generated on the waveguide wire after power-on with a magnetic ring matched. The precise position data can be calculated by capturing the time difference of wave transmission.