How “Smart” Components are Getting Smarter: Valves, Bearings, Gearboxes and Brakes

At a Glance:

Integrating smart technologies, such as wireless sensors and software, into mechanical components improves functionality. But there are limitations, too.
This roundup of current features in valves, bearings, gearboxes and braking systems, is crafted around use cases, limitations and future capabilities.

Yesterday’s valves, bearings, brakes, gearboxes and actuators pale in comparison to today’s advanced versions of these components. Integration of sensors, software and more has enabled achievement of unprecedented levels of functionality and proactive maintenance, resulting in ongoing cost savings and greatly improved productivity for users.

However, while these five components have evolved with the incorporation of wireless sensors and intelligent software systems, some limitations still exist.

To gauge the progress of how smart technologies have so far improved these basic machine components and what’s to come, Machine Design has assembled a roundup of current features, use cases, limitations and future capabilities. First, a look at valves.

Smart Valves: Self-Tuning Valve Curves Ahead

Thanks to IoT technologies, current smart valves provide superior performance compared to their traditional counterparts in carrying out the same function: opening and closing an aperture for the controlled flow of gases or liquids.

In smart valves, real-time precision measurement and flow control capabilities instantaneously detect leaks, which obviously minimizes waste of materials, but also boosts safety. The automated control and ongoing adjustment of flow to match pre-set parameters also ensures the smart valve provides a steady, precise supply of gas or liquid, which optimizes the industrial process at hand.

In addition, real-time data analytics of today’s smart valves also enable speedy system performance analysis, explains Kamal Rupareliya, director of products at Intuz, a digital transformation (AI, IoT, mobile and web apps) firm based in California. Operators can quickly make educated decisions based on up-to-date pressure/flow readings and maintenance alerts, decreasing the risk of operational disruption.

Despite all this, some types of smart valves require manual assistance, which is difficult to manage in industrial settings where there are many valves. Rupareliya has found, however, that “it’s the retrofit devices and the early-generation ‘sensor-only’ smart valves that still force technicians to turn a hand wheel when batteries drain or networks drop. By contrast, the newer fully-actuated electric or pneumatic valves—shipped with their own position sensors, motor and fieldbus card—stay completely hands-free once they’re enrolled in SCADA or a building automation system.”

The key to reducing manual intervention, he says, is to layer rule-based or machine learning-driven logic on top of the valve’s edge telemetry. “With a simple gateway,” he explains, “we stream flow, pressure and position data into the plant’s manufacturing execution system, set time- or event-based rules (for example, ‘flush at 02:00’ or ‘close if flow spikes 20%’) and let the system execute autonomously.”

Rupareliya also notes that integration of predictive maintenance capabilities into smart valve systems is straightforward to set up. Intuz favors the approach of adding a low-cost edge computer to the actuator of the system (where the actuator already exposes motor-current or vibration signals over HART, IO-Link or Modbus), and the signals are mapped to a cloud machine-learning service. “Within days, we’re receiving ‘early-wear’ alerts,” says Rupareliya, “instead of discovering a stuck valve during a line shutdown.”

Looking ahead, he says we should expect smart valves to be marketed that have embedded AI that self-tunes valve curves, digital-twin APIs that let engineers simulate process changes before a single degree of rotation, and zero-trust firmware that updates as easily—and securely—as a phone operating system. “In short,” Rupareliya concludes, “valves will evolve from connected components to autonomous, cyber-secure agents in the flow loop.”

Robotic arm with Ogura brakes — A robotic arm with three Ogura spring-applied brakes on the pivot joints.

Smarter Bearings: Access to Data is Key

Traditional bearings facilitate movement of components by providing support and reducing friction between surfaces, but like other smart devices, “condition-monitored” bearings offer data-based insight into their own function and overall machine function. Condition monitoring provides real-time detection of abnormal conditions that could cause damage, and prompt suitable immediate intervention.

Whether cylindrical, ball or another type, today’s smart bearings feature external sensors that detect vibration, temperature and speed, direction, load and the presence of debris. In fact, various industry sources estimate that contamination, along with poor lubrication and poor fitting, account for 70% of bearing failures.

Today’s condition-monitoring systems range from simple to complex, depending on what the customer wants to measure, explains Melissa Quinlan, marketing communications manager at bearing manufacturer The Timken Company. Some teams want to understand which component in a system is starting to fail, while other teams want only to be alerted that something in the operation of a machine is starting to change, and then they investigate further.

But Quinlan says that no matter what the purpose of the smart bearing or whether the conditioning monitoring system is hard-wired or wireless, data storage must be carefully considered. It can still be challenging to securely connect with and access the data that today’s condition monitoring systems for bearings and ancillary equipment can collect.

“Does the customer want to maintain control of the data and keep it completely internal or are they okay with data being stored in the cloud and outside their firewall?” Quinlan asks. “Many technologies do not offer on-premises data storage, subjecting the company to data storage issues. Additionally, in a large building or plant, sensors may not be able to consistently connect and transmit data to and from each other.”

Looking at other challenges companies may face when using condition monitoring, Quinlan lists a learning curve in setting up the system and learning how to use the data to make informed decisions. However, she believes progress will continue to be made with this in years to come. The use of condition-monitoring tools will deepen as teams begin to understand how to most effectively use available solutions.

Looking at the future of smart bearing tech itself, Quinlan says one area where some evolution will likely occur is connecting the data that’s being collected on an entire system (which is the simpler approach many firms favor right now) to individual bearings. This will engage order of a replacement bearing “before it actually fails and the equipment is idled,” Quinlan explains.

Ogura Industrial’s micro brake (with the penny, for comparison) is designed for very light torque micro-motor applications.

Where Smart Gearboxes Will be Seen First

Gearboxes are critical components that convert speed and torque into motion in conveyor systems, robots and other material handling systems. In many large plants, the number of gearboxes can span from hundreds to thousands. Managing lubrication oil replenishment is therefore challenging for plant maintenance teams.

Smart gearboxes that send alerts that lubrication is low or that another issue is in play make protecting gearbox operation and extending the lifespan of these components much easier. “Smart gearboxes will soon become a norm in the industry,” says Connor Robinson, Bosch Rexroth sales product manager. “Sensor connection points will be present and sensors will detect vibration, operating time, temperature, oil levels, rpm, etc.,” as well as ambient temperature, motor amperage and/or motor frequency.

Robinson believes smart gearboxes will first find applications in the joints of industrial robots. “[These systems] are quite expensive and are typically used in a critical role within the factory, for example moving hot parts, in a dangerous position close to machinery or presses, so downtime is costly,” he explains.

However, there are substantial current barriers to entry, says Robinson. These barriers include the need to store large amounts of data and also the excessive current dependence on predictive modelling [instead of managing and acting on real-time data that smart gearboxes provide]. “Moving away from straight mechanical components to today’s ‘smart components’ means our maintenance teams will need more education and training,” Robinson explains. “Almost all mechanical maintenance members will need to learn IT or electronics.”

Ogura Industrial multiple disc brake — Ogura Industrial developed a high torque multiple disc brake capable of 30,000 Newton meters.

Braking Systems Advancements

Braking systems obviously slow or stop components of machines or entire machines by converting kinetic energy into some other form of energy. Traditionally, a resistive force such as friction has been used (and is still used, for example in drum and disc brakes) and kinetic energy is converted to heat. However, new braking technologies such as regenerative braking (conversion of kinetic energy into electric energy) have been introduced, allowing stored energy to be used later.

Electromagnetic brakes use magnetic fields generated by electric currents flowing through an electromagnetic coil contained within the braking mechanism. The lack of direct physical contact results in less wear compared to traditional hydraulic brakes. But even with friction brakes, there have been new materials introduced, from metallic alloys to ceramics, that provide greater durability under high temperatures. Advanced ventilation rotors and cooling ducts have also been introduced to dissipate heat.

“For robotics, it’s best to use pulse width modulation (PWM) as it allows you to reduce power to the brake by up to 25%,” explains Brian Mather, VP at brake manufacturer Ogura Industrial. “In turn, this reduces heat. Many engineers and machine designers are still not aware of PWM. It also extends lifetime of batteries in battery-powered systems.”

Looking at other current developments, Mather says servo motors with hollow shafts are now common in new robotic designs, and only some firms like Ogura offer brakes that can be mounted on these shafts. In the future, he foresees that “brakes will continue to get smaller, lighter, thinner, faster and cooler.

One way to reduce temperature is to design a brake to have full power to release the brake, but then reduce the power after it is released. There is also a trend to seal the brake within the design of the machine and there are many ways to do that, such as having brakes integrated into the motor or assembly."

“There will also be development in detection of the brake being applied on safety-critical applications,” he says. “The traditional way of recognizing brakes are on or off is a limit switch, but this can be done through electronic feedback.”

Miniature brakes are also increasingly in demand, as motion control systems in surgical robotics and other systems get smaller. Mather says so far, these (spring-applied) brakes are as small as 10mm OD (outer diameter).

Condition-monitored bearing — Much like other smart devices, “condition-monitored” bearings offer data-based insight into the function of the bearing and the overall machine function.

Wireless lube sensors convert electric motors into smart, connected devices. Condition monitoring provides real-time detection of abnormal conditions.

Unprecedented Precision with Smart Actuators

Unlike standard actuators—the controlling component of motion control systems found in a wide range of machines—smart actuators also provide fault reporting and performance feedback. As with other condition-monitored components, this means maintenance teams benefit from real-time detection of and reporting of issues such as power loss, motor overheating and communication errors.

However, in machine design, smart actuators provide new levels of reliability and precision in motion control due to the feedback provided. They also help simplify applications in industrial settings from the automation of airflow to improved autonomous guided vehicle control, material handling and much more.

Precise feedback on position can be provided in a smart actuator through integrated analog and digital I/O with a programmable logic controller (PLC). Ethernet/IP connectivity can also enable direct connection to a PLC, providing more options for the complex patterns of motion demanded across many industries today.

But as with other smart devices, integrating smart actuators is not without challenges. “It’s a different and unique technology, so there is user apprehension,” explains Carl Richter, VP and general manager at Kyntronics. In addition, the cost of smart actuators is higher than hydraulic power units, but Richter adds that “the value is understood based on the operating costs, efficiency, maintenance and sustainability gains.”

While the technology can be incorporated into any drive system using standard Proportional-Integral-Derivative (PID) controller techniques, Richter notes that “higher speeds with larger loads (e.g., some hydraulic systems run a 30T cylinder at 10in/s, requiring ~120HP) cannot be added to an actuator. However, speeds can be increased using multiple power units.” At the same time, Richter says that over the next few years, smart actuators will be able to handle higher speeds and will also come with lower cost and more control capabilities for fine-tuning performance.