Integrate critical assets in a single network.

The worldwide pump market has witnessed significant uncertainty in recent years due to the sinking price of oil and other commodities. Stagnant end-user demand and stringent energy efficiency regulations create further challenges. Pump manufacturers also face difficulties when it comes to maintaining, servicing and managing on-field products.

Operational Challenges of Pumps

Pumps are extensively deployed in many process industries, including power generation, oil and gas, mining, and water and wastewater. For all of these industries, minimizing asset downtime and increasing process transparency is a high priority since it augments performance and cuts down on costs. Pump failures disrupt an entire process, leading to equipment service costs, expensive production losses, impaired product quality and increased production waste. In hazardous areas such as oil fields, fires may even be ignited, resulting in disastrous consequences. Failures, nevertheless, are often detected only after pumps actually malfunction.

Comprehensive on-site inspections are required to diagnose the location and causes of incurred failures before overhaul and reparation activities can be carried out. Since the whole process is time-intensive, plant downtime and accompanied costs quickly escalate.

The LPWAN architectureImage 1. The LPWAN architecture (Images courtesy of Behr Technologies)

Another critical aspect of pump operation that could be improved with monitoring is energy efficiency. According to Schneider Electric, pumps account for a quarter of total energy consumption by industrial motors and represent half of total energy saving potential. Energy costs constitute up to 40 percent of the total cost of ownership of a pump. Power consumption levels also increase along the product life cycle as pumps start to wear out. Keeping an eye on current operational metrics is key to identifying unusual patterns in energy usage and ensuring a timely and appropriate response.

With the pressure of economic volatility and operational challenges, pump manufacturers and process industry companies are turning to industrial internet of things (IIoT) technologies to enhance process proficiency, safety management and energy efficiency. Connected pumps, which mirror the idea of connected devices in IoT, are equipped with battery-powered sensors to capture various “health” parameters, such as vibration, temperature, pressure, flow rate, voltage and current. These sensors deliver real-time insights into the operation of a pump and its core components to facilitate condition-based monitoring and remote troubleshooting. For example, excessive vibration of the pump hints at wrong installation, misalignment or improper function of bearings. Early diagnosis of potential failure leveraging analytical models allows for predictive and preemptive maintenance, as well as the timely order and replacement of spare parts. Substantial reparation and shutdown costs can then be reduced.

Example deploymentImage 2. Example deployment

The Problem of Sensor Connectivity in Industrial Fields

The lack of communication infrastructure in brownfields and highly demanding industrial surroundings, however, pose great challenges in last-mile sensor connectivity, hindering the full realization of connected pumps. Many pumps are installed on sprawling and rough landscapes, underground, or even in explosive zones with hostile conditions and limited accessibility. With the deployment of hundreds or thousands of sensors, wired networks requiring extensive cabling to every endpoint are not viable due to significant installation and maintenance costs. Highly dangerous areas, such as explosive zones, impose additional stringent guidelines and regulations that complicate setup and upkeep activities, especially when the network will be retrofitted.

Wireless solutions entailing much simpler installation of sensors or transmitters are a more desirable approach. The problem is short-range radio technologies, such as wireless local area network (WLAN), Zigbee and Bluetooth, do not meet the range requirement of complex and vast industrial areas. In addition, cellular networks may fail to deliver consistent reliability due to insufficient coverage in remote, offshore or underground industrial facilities, typically in the oil and gas, mining or utility sectors.

These networks require high power consumption that involve regular battery changes and ongoing network fees that curtail return on investment (ROI). In particular, possible shutdowns of 2G, 3G and 4G networks when next generations of cellular connectivity arise and threaten to disrupt the communication infrastructure in the future.

Low Power Wide Area Networks

The emerging low power wide area networks (LPWAN), which target large-scale IoT applications, remedy the shortcomings of existing technologies in terms of battery life, area coverage and cost. LPWAN technologies use unlicensed industrial, scientific and medical (ISM) spectrum to transmit low-throughput messages with data rates varying from a few bits to several-hundred bits per second over very long distances. With a more than 10-kilometer line-of-sight range, these networks deliver a huge advantage when it comes to connection of widely dispersed pumping assets.

Moreover, the asynchronous communication protocol, which allows end devices to remain in “sleep” mode when no messages are sent, significantly reduces power consumption and extends battery life to multiple years. This low-power profile makes LPWAN ideal for data communication from battery-operated sensors, simplifying maintenance requirements considerably. What’s more, these networks can be deployed at a fraction of device and operational costs compared to other wireless alternatives.

Most LPWANs adopt a one-hop star topology whereby a central base station, serving as the access point, gathers data from large numbers of remote endpoints. Interfaced with an on-premise internal server or a third-party cloud, the base station forwards collected data using higher throughput backhaul connection (e.g. Ethernet) to the respective control system or analytics platform. Here, sophisticated built-in algorithms transform raw information into insightful and actionable IIoT intelligence that can be visualized on the user interface.

Despite their advantages over cellular and other M2M technologies in terms of power consumption, coverage and deployment cost for IIoT applications, existing LPWANs can have their downsides. Operating in the crowded license-free sub-GHz spectrum with other legacy radio systems, these solutions create severe inter-technology and inter-network interferences that disrupt each other’s operation. The co-existence problem greatly affects network reliability and diminishes overall quality of service.

Furthermore, certain proprietary LPWAN solutions are vendor-dependent, meaning the communication protocol is only compatible with radio chipsets produced by a defined manufacturer. Vendor-independence hinders users’ flexibility in designing their own IIoT architecture and reacting to future technological changes. Another widely known LPWAN operates a centralized backend infrastructure where all user data is rerouted to the central server in France, raising potential data privacy issues. Above all, the lack of standardization in the fragmented LPWAN landscape creates a major barrier to worldwide IoT scalability due to problems of network longevity, reliability and interoperability.

The New LPWAN Standard

To address existing drawbacks, a new LPWAN communication approach has been developed and recently approved as the European Telecommunications Standards Institute (ETSI) standard. It employs a unique data transmission method where transmission of a data packet is divided into short radio-bursts. The new LPWAN approach promises maximum spectral efficiency and robustness against other radio interferences—valuable network features in the license-free spectrum.

High spectral efficiency enables integration of thousands of end devices in one single network, while still securing reliable connectivity. Signal strength through concrete walls or heavy, rebar obstructions is also maximized. Furthermore, short “on-air” time of data packets makes the new approach especially power efficient. As a globally accepted standard, the protocol can be supported worldwide and deployed on any commercially available chipsets and gateways.

The innovative LPWAN standard brings a highly scalable, reliable and cost-efficient IIoT communication infrastructure into play. The “last-mile” sensor connectivity gap in brownfields can now be filled with an easy-to-retrofit, flexible and robust wireless solution. Remote monitoring of industrial pumps, especially the ones located offshore, underground or in hard-to-access areas can be secured. With enhanced asset visibility, field workers can be alerted when abnormalities are detected to execute maintenance activities in a timely manner and prevent costly downtime.

The high scalability of the communication network ultimately allows for effortless integration of other industrial critical and near-critical assets, beyond connected pumps, in a single network. Condition-based monitoring and predictive maintenance on the whole production facility, enabled by massive and reliable collection of operational parameters, can be realized to optimize process productivity and reduce operational costs.

References
1. Ahmed, Hussain. “How ‘intelligent pumping’ strategies address disruptive trends in water wastewater industry”. schneider-electric.com. https://blog.schneider-electric.com/machine-and-process-management/2014….