Rubber presents a challenge for optical-based measurement sensors. By nature, the black surface is difficult to capture reliable data from and accurately measure. This challenge is often intensified by the complex shapes into which rubber derivatives are extruded or molded.

As a solution to this challenge, 3D laser sensor manufacturers have optimised the design of their sensors to successfully implement scanning and quality control functions for both in-process and final product inspection applications in rubber and tyre manufacturing.

3D laser scanning

Rubber material comes in two forms on the production line, either as fresh and uncured from an extruder or a calender, or as a finished product (e.g., vulcanised tyres). Non-contact 3D laser scanning offers the most practical solution for inspection of both of these rubber material types.

Here’s why:

1. The soft, gummy nature of the rubber makes contact-type measurement ineffective. This measurement approach is also too slow to keep up with the high-speeds of continuous web material production.

2. 2D sensors require complex lighting to see black-on-black contrast. In some applications the lighting is placed underneath the material (e.g., when measuring the width of a strip), and hot sticking rubber can contaminate the lights. In addition, 2D can’t produce measurements related to object geometry (i.e., 3D shape), which means they are unable to measure critical features such as object flatness, surface angles, or part volumes, and are limited to contrast-based inspection. This makes 2D sensors a poor solution for scanning complex shape-based features on dark surfaces, or for operation in low lighting conditions.

          3. In comparison, 3D laser sensors are contrast invariants and generate high-resolution scans regardless of the material or lighting conditions. They also capture the complete 3D geometry of the scan target, including critical depth measurements on surface features such as grooves in a tyre tread. 3D laser sensors are also able to achieve the high speeds required for continuous web material scanning.

Laser profile sensors provide an ideal solution to both in-process and final rubber and tyre measurement and quality control applications. Built-in measurement tools for strip positions, including multiple groove location and depth measurement monitoring with automated alignment enable engineers to configure setup parameters––without requiring any measurement software development.

In addition, the ability to store multiple geometry configurations in the sensor makes changes between different recipes quick and simple, which is critical in minimising downtime for operations that make model changes multiple times per shift.

Application examples

1. In-Process Inspection

Extrusion Profiling with High-Resolution Gocator® 2440 Laser Profiler

Extruding rubber in a specific shape makes up the tread portion of a tyre. Measurement of the extrusion profile is carried out in-process, correcting the extrusion parameters in real-time to maintain the required shape. Key measurement parameters include thickness, width, and profile. Another required sensor capability is monitoring the position of surface features, such as ridges, center lines, and edges.

Profiling these tread extrusions is done by using 3D laser sensors to scan across the extrusion, generating a profile to which built-in measurement tools and pass/fail decision-making logic can be applied.

In this example, two Gocator 2440 laser line profilers are used to measure the rubber web’s extrusion groove pattern, geometry, and location with an X resolution down to 13 microns. Gocator 2440 sensors are able to inspect multiple grooves in a single setup, and groove measurements are unaffected by changes in surface angle relative to the sensor.

Most importantly, Gocator 2440 sensors generate critical 3D height data for robust shape measurement. 2D solutions are limited to contrast-based inspection.

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3. Final tyre inspection

Tyre Sidewall Inspection with High-Speed Gocator 2530 Laser Profiler

Traditional methods for measuring tyre sidewalls for defects such as bulges and dents suffer from too many false rejects (i.e., classifying a good tyre as defective). Due to measurement system limitations, many manufacturers have no choice but to “oversensitise” their sidewall bulge and dent measurement systems, resulting in costly manual inspection requirements for all rejected tyres.

In fact, some measurement systems cannot even distinguish between bulges or dents. However, with state-of-the art laser measurement precision and advanced built-in software analysis, false positive rates can be substantially reduced and, in many cases, eliminated altogether.

Using a Gocator 2530 laser profiler the engineer is able to generate full surface point cloud geometry data in order to detect small defects (down to 28 microns X resolution) anywhere on the sidewall surface. The sensor also delivers complete scan, measurement, and control at 4 kHz, allowing engineers to meet stringent cycle time requirements––with no need for industrial PCs or external controllers.

In this configuration, two profile sensors are typically used, one for each sidewall (top and bottom buddy system). A third sensor is often used to monitor radial runout of the tread.

Leveraging 3D Laser Scanning and Inspection

Laser-based laser triangulation sensors meet the high speed and high resolution requirements for accurate rubber and tyre measurement. These sensors are used in a variety of in-process and final inspection applications, including extrusion profiling and tyre sidewall inspection.

Adding 3D laser sensors for automated quality control is vital to reducing scrap and rework, and improving final product quality by maintaining consistency throughout the tyre manufacturing process.

Courtesy of LMI Technologies www.lmi3d.com

The order book for Curemaster is strong with a surge in orders during the first two months of the year. The executive anticipates continued momentum throughout the year, driven by increasing global demand for advanced, sustainable curing solutions.

FORWARD INTEGRATION

According to Rudman, digitalisation is playing a crucial role in enhancing the efficiency and reliability of curing presses. “Digitalisation provides real-time visibility into production processes, allowing manufacturers to monitor efficiency and product quality continuously. With a clear overview of operations, manufacturers can identify inefficiencies and ensure production targets are met. The HF XPLORE digital portal offers access to critical data at all times. It provides insights into machine health, predictive maintenance alerts and production performance. The system helps track efficiency, detect potential failures and optimise operations by identifying areas for improvement,” he said.

Artificial intelligence is also slated to play a key role in electrical heating, ensuring stable temperature control within the platens. Machine learning is being developed for predictive maintenance, helping to forecast bladder life and detect potential failures before they occur. These technologies are part of the company’s development roadmap, focusing on improving reliability and efficiency in curing press operations.

He also noted that as tyre compounds evolve, curing requirements will change, making electrical curing a more suitable solution. Unlike steam-based systems, where temperature is directly linked to pressure, electrical curing allows independent control of both factors. This flexibility is crucial for processing new materials that may not tolerate traditional curing conditions.

“In steam curing, the relationship between pressure and temperature is fixed. For example, achieving a temperature of 200 degrees Celsius requires increasing the pressure to 20 bar. With electrical curing, temperature and pressure are completely separate, enabling curing at lower temperatures while maintaining the necessary pressure levels. This capability is particularly significant for future materials, which may require curing at 160 degrees Celsius but at much higher pressures,” explained Rudman.

The shift towards electrical curing is expected to gain momentum, particularly for high-end and specialised tyres that demand more advanced curing strategies. While steam curing will continue to be used for lower-segment applications, the upper range of the market, especially where sustainability and material innovations are key factors, will require the precision and adaptability that electrical curing provides.

OVERLAPPING TECHNOLOGIES

There is a clear trend in the market where customers are seeking more customised solutions rather than standard off-the-shelf curing presses. Manufacturers now have unique requirements including features like electrical curing, digitalisation, automated loading and unloading and seamless integration with factory infrastructure and tyre transportation systems. As a result, the demand for tailored solutions is increasing, making flexibility a key factor in the adoption of new curing technologies.

“Curemaster is designed with upgradeability in mind, ensuring that tyre manufacturers do not have to replace entire presses when looking to modernise operations. Even older HF curing presses that have been in service for more than 20 years can be upgraded to electrical curing without altering the mechanical structure. This allows manufacturers to transition to more efficient curing technology while retaining the existing equipment. At the same time, the new Curemaster is available as a fully electric system from the outset, offering a ready-made solution for greenfield projects,” averred Rudman.

Nonetheless, the biggest business potential currently lies in retrofitting existing curing presses rather than selling entirely new equipment. “Many customers prefer upgrade kits that allow them to transition to electrical curing while maintaining current production setup. While greenfield projects present a significant opportunity for new fully electric presses, the greater demand at present is for retrofit solutions, as it provides a cost-effective way to improve efficiency and sustainability without major infrastructure changes,” he added.

PROCESS OVERVIEW

Most curing press suppliers have introduced electrical curing solutions. There are two main approaches to electrical heating, which are electromagnetic (induction) heating and resistive heating.

Electromagnetic heating method involves placing a coil outside the tyre to generate heat. However, there are concerns about how this method interacts with the tyre’s internal bead wire and breaker package. Since the long-term impact of electromagnetic fields on tyre integrity has not been fully tested or verified, there are still some uncertainties regarding its effects on tyre quality.

In contrast, resistive heating, which the company employs, places coils directly inside the plate, ensuring controlled and targeted heating. This method eliminates any risk associated with electromagnetic interference and allows precise temperature application only where needed. While both technologies are viable, resistive heating offers greater reliability and consistency in maintaining tyre quality.

“One of the key advantages of electrical curing is its rapid heating and cooling capabilities. The nitrogen used in the process can be heated from 20 degrees Celsius to 250 degrees Celsius in less than 20 seconds and cooled back down in the same time frame. This is achieved through continuous nitrogen circulation, where the system directs the flow through either the heater or the cooler as needed. In terms of curing time, electrical heating currently matches steam curing with a typical cycle of 10 minutes per tyre. However, there is significant potential to reduce curing time by 10 to 15 percent as electrical systems can operate at higher temperatures and offer more precise control over the process,” informed Rudman.

Nonetheless, steam curing has a predominant risk of mishaps in the bladder, which could lead to an explosion. The Curemaster is designed with a fully encapsulated dome, ensuring that any pressure build-up remains contained. If a failure occurs, the pressure is released downward instead of sideways, reducing the risk of injury.

The locking system is also unique. Even if there is a total power or hydraulic pressure loss, the press cannot open unintentionally. This containment and locking mechanism ensure a high level of safety during operation.

CHALLENGES AND OPPORTUNITIES

According to the executive, the biggest challenge in the curing press business comes from cost competition as lower-cost manufacturers pose a significant pricing challenge. However, from a technological standpoint, the company offers unique features that set it apart from competitors. While competitors may have cost advantages, HF’s focus on advanced technology, automation and digitalisation allows it to capture market share by offering superior functionality and efficiency.

The passenger car and truck segments remain the company’s primary focus owing to the highest growth potential. Additionally, the company sees an emerging opportunity in motorcycle and bicycle tyre curing, particularly with electric heating technology. HF is among the first to introduce electrical curing for these segments, positioning itself as an industry leader.

While HF is active in the passenger and truck segments, it has opted not to enter the off-the-road tyre market due to its relatively small size and intense competition. The segment still relies heavily on traditional mechanical presses, making it less attractive for innovation-driven solutions.

The company continues to refine the Curemaster lineup by introducing new materials, insulation techniques and design concepts. The company is particularly focused on increasing automation to enhance efficiency and reduce operational costs.

Beontag, one of the world’s largest manufacturers of self-adhesives and smart tags such as RFID, NFC and BLE, has entered into a collaboration with Kumho Tire to develop RFID-enabled tyres for commercial and passenger vehicles.

The partnership will see new Kumho tyres use Beontag's TyreTag RFID technology. Traceability will be possible with the RFID-enabled tyres from the point of origin to recycling and disposal. Following years of research and development, according to both the companies, the new RFID-enabled tyre is very robust and dependable, able to survive high temperatures and pressures over the course of years of intensive use. The new TyreTag-enabled tyres' traceability will also adhere to the forthcoming Ecodesign for Sustainable Product Regulations (ESPR), which will need Digital Product Passports (DPPs) and be in force for tyres starting in 2028–2030.

Thiago Horta, Global VP of Digital Transformation, Beontag, said, “We are extremely proud to share what we have achieved in our partnership with Kumho Tire. Through rigorous testing, we have worked hard to develop the necessary technology and durability capabilities in these RFID-enabled tyres; I look forward to continuing this journey with Kumho Tire for years to come”

Jihon Park, Assistant Manager with Kumho Tire, said, “Kumho Tire has been producing RFID-enabled tyres since 2013. Beontag’s technical expertise and collaborative approach were instrumental in helping us meet our rigorous standards and enhance our technology. We look forward to delivering even greater quality and reliability to our customers around the world.”

Goodyear has launched the Value Simulator, an online tool designed to assist fleet operators in visualising the possible financial and environmental advantages of upgrading their mobility and tyre solutions. The simulator is now available on the company's truck tyre website and is a component of Goodyear Total Mobility, the company's end-to-end solution for commercial fleets.

According to Goodyear, the tool takes into account typical fuel consumption and cost, fleet size and breakdown frequency, vehicle mileage and maintenance trends and the kind of transportation and route profile. After data is entered, the simulator instantly estimates the potential decrease of CO2 emissions, maintenance and fuel costs, and annual breakdown-related cost savings. Additionally, customers can customise simulations according to their own fleet characteristics.

The CO₂ reductions are based on theoretical fuel usage using EU tyre label values as a baseline; real savings may vary depending on factors including driver behaviour, vehicle condition and road conditions. Additionally, based on user interaction, the simulator suggests appropriate Goodyear goods and services. These recommendations can be used as a springboard for talks with Goodyear's staff in order to do a more thorough study and develop a customised fleet plan.

Maciej Szymański, Marketing Director Commercial at Goodyear EMEA, said, “At Goodyear, we are committed to supporting transport fleets in maximising efficiency, increasing competitiveness and promoting sustainability. The Goodyear Value Simulator confirms our dedication to customer-centric solutions and helps fleet managers to make informed decisions that aim to drive tangible benefits for their operations. With the Goodyear Value Simulator, fleets can visualise the potential financial and environmental impact of adopting Goodyear Total Mobility. From reducing breakdown costs to enhancing fuel efficiency, our solutions are designed to deliver real value to our customers.”

Webfleet, Bridgestone’s globally trusted fleet management solution, has launched its new flagship Driver Terminal, the PRO X, designed specifically for truck and van fleets.

By providing direct tablet access to Webfleet fleet management services, the PRO X links drivers and companies to streamline work administration. Fleets can utilise a variety of sophisticated Webfleet features, such as workflow management, electronic Proof of Delivery (ePOD) and two-way communication between drivers and fleet managers thanks to the pre-installed Webfleet Work App. They can also access other Webfleet services, such as Cold Chain, Remaining Drive Times and OptiDrive ranking, which allows drivers to view peer performance.

Van and truck fleets may enjoy the best-in-class professional navigation with the newest technology, like smart warnings for traffic or low-emission zones, major points of interest for trucks and EVs and live ETA reporting, with easy access to TomTom GO Fleet.  Additionally, when paired with OptiDrive, the motorist gets immediate feedback to help them drive better. Pre-installing maps is now simple, and they are updated automatically every month. With its wide anti-glare screen, sturdy construction, detachable battery and user-friendly controls for instant access to essential programmes, the new high-performance Driver Terminal helps professional drivers both in-cabin and on-site.

With an integrated Mobile Device Management (MDM) system that enables fully remote management of the devices' home screen, app auto-start and other features, it is configured for a quick roll-out in the field and can be tailored to fit various corporate demands. Because it is Android Enterprise Recommended and integrates Webfleet's and TomTom's expertise in sophisticated navigation, devices may be more rapidly customised to meet user demands. Beginning in March 2025, the PRO X will be sold in Europe, Australia and New Zealand, with other territories to follow later this year.

Annick Renoux, Vice President, Webfleet Europe, said, “At Webfleet, we are always committed to delivering smart solutions that enhance the working conditions and safety of our customers and their drivers, powered by the latest technology. That’s why we are proud to introduce the new PRO X – now with even more functionality to help fleet managers streamline their operations, boost efficiency and strengthen their connection with field teams like never before.”