Fluid Flow Machinery 4.0: a two-way conversation

The leading pump manufacturer only has a 9% share of the total worldwide pump market, which is estimated to be around €30 billion, showing how fragmented the market is. The same is true for the compressors, controls and valves market. The companies that manufacture these products are traditionally the largest exhibitor group at ACHEMA, and this year they have booked 34,000 m² of exhibition space to showcase the potential for innovation of the 'Mittelstand' (mid-sized companies).

Industrial producers have to constantly find new ways of boosting process efficiency. To effectively manage cost (energy and labour costs), quality (reproducibility) and reliability (occupational safety and environmental protection), companies need to continually increase the level of automation. ZVEI (German Electrical and Electronic Manufacturers Association) reported that sales by German process automation suppliers were up 6-7% in 2014, and growth is expected to continue in 2015. AMA (Association for Sensors and Measurement) has also reported increased order intake.

This general trend in process engineering also has an impact on pumps, compressors, controls and valves. Sufficient versatility must be designed into these products to ensure that they fit seamlessly into the overall automation strategy, and the communication capabilities need to be enhanced.

To an increasing extent, manufacturers are responding by offering system solutions or package units which go beyond the basic functionality of a process pump, compressor or control valve. While all relevant technology is connected to centralised process control systems, components are fitted with distributed intelligence. This reduces the load on the central control systems and makes it easier to adapt the equipment when changes are made to the process. Why is this type of versatility important? At the 2014 Namur General Meeting, the individualisation of production, shorter product life cycles, fluctuating sales and faster time to market were cited as reasons.

Intelligent, distributed, network enabled

Industry observers expect that substantially more intelligence and functionality will be migrated to the field level. Modular design is an additional factor. Subsystems are designed to fit together like LEGO bricks. Components can be combined in different ways to meet application needs, and it should be possible to swap them in no more than an hour. Versatility must be built into the equipment to allow rapid adaptation and integration into a variety of systems.

To provide connectivity to higher-level control systems, manufacturers must design enhanced communications functionality into the equipment (based on real-time-enabled Ethernet bus technology, etc). In addition, onboard microprocessors and stored algorithms must be capable of autonomously executing a defined set of functions. Bidirectional data transfer must be supported. The Industry 4.0 concept is built around the flow of information from high-level control systems to field devices and between different devices (for example, between a pump and a valve or a compressor and a valve).

There is another argument in favour of this approach. Equipment designed for and operated in a system context is generally more reliable and tends to be less fault-prone. This is a very significant consideration in the international OEM business. Every service call-out to repair a fault at a remote location reduces the operating margin.

Brussels continues to raise the bar

Energy efficiency is a 'sleeping giant'. The goal of NAPE (German National Energy Efficiency Action Plan) that was passed in December 2014 is to wake up the giant and make it the second strategic element in the energy transition roadmap. Funding is to be made available for certain energy efficiency measures. NAPE places the emphasis on consultancy services and networking. The government has largely avoided the regulatory route.

The Ecodesign Directive is a different matter. At the European level, the legislative process got underway in 2005 to address the issue of electricity consumption and CO₂ emission.

The directive for electric motors (EC640/2009) plays a key role in eco-friendly design. It applies to pumps as well as compressors. It effectively forces manufacturers to concentrate on high-efficiency motors and frequency converters for speed control. Later on, and also as a result of EU regulations, increased emphasis was placed on the hydraulic efficiency of pumps.

Brussels is introducing stricter regulations in 2015:

• From 1 January 2015, all electric motors rated between 7.5 and 375 kW must either be IE3 compliant or IE2 compliant with a frequency converter.
• From 1 January 2015, certain glanded water pumps are required to have higher hydraulic efficiency (minimum efficiency index MEI ≥0.4).
• From 1 August 2015, glandless standalone heating and cooling system circulation pumps must have an energy efficiency index not greater than 0.23 and the same applies to circulation pumps that are integrated into heating systems. By 1 January 2020, circulation pumps integrated into existing products must also have an energy efficiency index not greater than 0.23. It will then no longer be possible to replace heating circulation pumps integrated into products if the pumps were placed on the market prior to 1 August 2015.

With the directive for electric motors that went into effect in January 2015, the EU has placed greater emphasis on the system approach. ZVEI expects that this will stimulate growth in the electric drive technology market.

Brussels has now become a 'natural' development partner for manufacturers. Suppliers in the premium segment are by no means dissatisfied with Brussels. Technical complexity gives manufacturers a major market entry barrier to ward off potential competitors. Advances in technology designed to increase energy efficiency are difficult to imitate, and that creates an additional impediment to product piracy.

Energy efficiency: regard the larger picture

Compared to standard motors, high-efficiency motors are 2-7% more efficient depending on the power rating. When the standard principles of good pump design are applied - which is always recommended - and a well-thought-out system approach is taken, including speed management, another zero can be added to those figures and energy consumption can be reduced by 30-70%. Frequency converters have real advantages but they can also cause problems when they compensate for (neutralise) wear-related performance degradation. It often does not become apparent that this is happening until wear reaches the point where it causes failure.

There can be no doubt that pump energy efficiency is an important issue. However, the significance can be relative depending on the particular industry and application. Energy consumption could well account for 90% of the life cycle costs for a well pump used in the continuous extraction of ground water. 40-65% of the life cycle costs of a pump which is used in an industrial process and runs under a high mechanical load are attributable to repair and maintenance (source: ReMain). According to the final ReMain report, 37% of pumps in the process industry are only operated at short duty cycles. These costs exceed the cost of the energy used to drive the pumps.

Controls and valves 4.0: when will systems go wireless?

Besides process control systems and sensors, actuators play an important role in automation and process engineering. In its 2014 sensor trends report, AMA reports that direct sensor-actuator connectivity is on the increase.

Controls and valves can adjust material flows to regulate process parameters such as pressure, temperature, flow rates and fill level. 'Intelligent' control valves with add-on modules are available that not only perform the control function but also automatically detect the need for maintenance or repair before a fault occurs. In the final analysis, these smart controls and valves improve production reliability, increase cost efficiency and help protect the environment. Suppliers expect that actuators will be used to a greater extent in control loops in the future. This could ultimately lead to wireless control. The actuator technology already exists.

Wireless sensing is a promising branch of sensor technology. Wireless measurement data transfer is not really new, but its potential in the industry has only recently been recognised. The technology looks very attractive, but there are hurdles to overcome such as real-time capability and reliability, and they are slowing the pace of introduction.

Actuator systems continue to rely on the traditional technologies: electric, hydraulic, pneumatic and electrohydraulic. But even here, more and more control and diagnostic functionality is being built into the drives. This is another application for distributed intelligence.

Electric valve actuators have the advantage that they can easily be connected even over large distances and they are relatively lightweight. Pneumatic systems have short actuation times and withstand long duty cycle ON times. However, the actuator is large and heavy. Hydraulic systems are maintenance intensive, but a smaller actuator generates more force compared to a pneumatic system.

One supplier is currently talking about a paradigm shift in single-use technology. Manual systems can be replaced with devices suitable for automation and control that support fault-free operation and continuous documentation by the monitoring system. The valve body and the actuator on the new product are connected using a special locking mechanism. Following use, the valve body is removed and the actuator remains in the system for repeated use. If necessary, the valve actuator can send feedback to the monitoring system, adding the final element needed to fully monitor the control loop. The manufacturer claims that this approach facilitates process reproducibility, documentation and validation in pharmaceutical production.

Compressors 4.0: more efficient generation of compressed air

A big campaign took place in Germany a number of years ago to increase the efficiency of compressed air generation, and it served as a blueprint for similar campaigns by the German Energy Agency (dena). A study by Markus P Rößler (TU Darmstadt, 2014) indicates that more opportunities exist to increase efficiency.

Between 2002 and 2012, companies were able to increase energy efficiency in the total compressed air system by an average 5-10%. An increase greater than 10% would be technically possible but in most cases would be prohibitively expensive. The increased use of high-level control systems, drive motors with frequency control, gearless drives and permanent magnet motors instead of asynchronous motors could help boost efficiency.

Besides the actual generation of compressed air, the system context is also important. Users are making a greater effort to recover heat even on older compressors. They are also looking at optimisation of auxiliary equipment such as dryers. From the overall system perspective, minimising leakage yields the best cost/benefit ratio. Setting the pressure to the lowest possible level for the application can also boost efficiency. More and more companies are embracing operational energy management.

No radical change in the compressed air generation process is expected in the next 10 years. The main emphasis will be on overall system optimisation. The required use of IE 3-compliant electric motors will lead to further energy efficiency gains. On systems with variable compressed air consumption, users are looking for durable actuators that react quickly and continue to work reliably even in applications with frequent start-stop operation. Variable speed compressors and higher level controllers can reduce energy costs by substantial amounts. Energy consumption can be reduced by as much as 30-40%.

In the future, demand will continue to increase for oil-free compressed air and not just in the medical equipment, pharmaceutical and food industries. Greater environmental awareness will extend the horizon of oil-free technology to standard applications as well.

In the era of big data and Industry 4.0, systems and applications will become more intelligent and they will be integrated into complex industrial infrastructure, claims a leading manufacturer. One-stop shopping is an attractive option for a user base that increasingly prefers complete solutions.

Under the compressed air contracting model, users purchase compressed air at a fixed price rather than generating it with their own equipment. The industry is convinced that this business offers considerable potential.

TOR - the gateway to a systems approach

Experienced systems designers are normally able to combine functionality and efficiency. Inexperienced designers are unlikely to be able to do that. With reference to eco-friendly design, you could make the following provocative assertion: it is very possible to take a number of highly efficient, well-designed machines and put them together in a way that creates a poorly designed system which is very inefficient. That at any rate is the opinion of Dr Ulf Lorenz, Dr Gerhard Ludwig and Prof. Peter Pelz at TU Darmstadt, who are the originators of the TOR concept. So what is it all about?

New design strategies are needed to save significant amounts of energy on fluid systems that consume energy. A product approach or extended product approach must give way to a system approach. Like chess players, designers have to simulate and analyse various scenarios until they have found the system topology that performs a process function with minimal energy consumption. Mathematicians and engineers at TU Darmstadt are working together to find solutions, and the TOR virtual design software is being developed by the Fluid Systems Technology Department. The term TOR (Technical Operational Research) refers to both the virtual design software and the new research body. The goal is to provide a decision-making aid to support system design and operation, and to assess energy efficiency.

Summary

Digital networking in fluid flow systems based on distributed intelligence at the subsystem level creates a straightforward pathway from the product approach to the systems approach. The availability of relevant information on the process and the set point/actual operating parameters of pumps, compressors, controls and valves supports maximum utilisation of input energy, predictive repair and maintenance and higher system availability.

Extensive use is being made of the capabilities offered by today’s smartphones, primarily to query and modify set point/actual values. It will probably not be long before wearables like Google Glass become part of the toolkit. Maintenance engineers will be able to read all of the work procedures on mobile displays that are located right in front of their eyes. The instructions may be presented in a form similar to the way players receive messages from their avatar in adventure games.

Source: ACHEMA Trend Reports