Transparent Wireless at Cano Petroleum
Cockrell Ranch Waterflood project is an ambitious enhanced oil recovery project using wireless technologies reaching across more than a dozen square miles of the Texas Panhandle. Cano Petroleum uses state-of-the-art technology and methods to successfully recover oil from wells that would have once been considered “tapped.” The waterflooding process uses pressurized water to move through the formation, driving raw crude oil out of the ground from wells. Equally challenging was how the industrial automation and wireless networking technologies ties it altogether.
Boss Automation of Spearman, TX, designed and installed the discrete automation platform and a control network to monitor pressure and flow of this water into the wells. The project evolved into the design and implementation of a new, fully automated, self-monitored supervisory control and data acquisition (SCADA) system. The system was designed to gather, assemble, and transmit data from wells and injectors and send it to a master station. This allowed day-to-day field operation to be monitored and controlled so collected data can be used to produce detailed production models.
System considerations included: Reliability, maintainability, ease of use, as well as the ability to obtain local support. With help from Rexel, the local Allen-Bradley distributor, Boss Automation chose Allen-Bradley hardware, Rockwell Automation software, and ProSoft Technology wireless communications.
The SCADA system consists of one Allen-Bradley ControlLogix at a Main Master Station tied to four A-B ControlLogix slave sub-stations and more than 100 custom-built remote terminal units (RTUs), each with an A-B MicroLogix 1100 programmable logic controller (PLC) and a ProSoft Technology Industrial Hotspot radio. The main master station and four sub-stations represent the backbone network of the project. Each of the four sub-stations acts as a master for its respective sub-network. All communication from the wells and injectors to the sub-stations, and from the sub-stations to the main master station, is handled wirelessly using the ProSoft Technology Industrial Hotspot.
Paul Brooks, business development manager, networks portfolio for Rockwell Automation notes, “For this application, ProSoft’s wireless technology provides the backbone communication for the integration of this system creating a reliable, industrial and transparent network, which allows Cano Petroleum to successfully monitor process data remotely.”
At the main master station, a human machine interface (HMI) application for the system was developed using Rockwell Automation RSView 32 software. Graphical interface screens have proven to be user-friendly, and the Messenger Pro feature provides the operators with detailed information about alarm conditions in human voice, by automatically calling the cell phone of the person on call. The ProSoft Technology RadioLinx OPC Server is used on the remote access computer to monitor the status of the radio network.
4,500 I/O connections
More than 3,500 discrete input/output points and 1,000 analog points is gathered and moved across the wireless network at about 11 Mbps to the main master station where it is then assembled into data log models, then interfaced by Cano’s proprietary modeling software.
Rexel provided logistical and technical project support. ProSoft Technology provided engineering support throughout the length of the project for the large-scale wireless network.
Patrick Haga, ProSoft Technology wireless engineer, attributed technical success to planning and prior care taken. “I probably spent close to 80 hours working with Boss Automation control engineers on a path study using ProSoft’s Pathloss software,” continuing collaboration throughout project installation on network layout and on the strategy for PLC messaging.
The network covers more than 12 square miles. The longest link is about 2 miles, and a bulk of the radios were positioned in an area of about 3 square miles, which created timing concerns, Haga says. With the network’s size, “if all radios are trying to communicate at the same time, you can quickly swamp your bandwidth with RF collisions and retries.”
Haga continues, “This in mind, we discussed the need to create a polling style network rather than having all the radios trying to communicate at the same time. It takes a lot of planning up front to successfully install a radio installation of this size, and ProSoft’s Technical Support group provides an excellent planning resource.”
Boss Automation’s Chris Deakin, says, “The process is incredibly reliable, consistent and makes for an essentially self-managed site. From the main SCADA monitoring station, the operators are able to see virtual diagrams of the wells and what is going on within them, as well as all the data collected by the RTUs and control units.”
The project, live in spring 2008, has had near zero downtime. “The wireless network works so seamlessly and reliably that it is virtually transparent,” Deakin says. “I asked the customer how they liked the wireless network. Their response: what wireless network?”
Analyst observation: Wireless lowers projects costs
Cockrell Ranch Waterflood project illustrates three important points about industrial wireless, says Harry Forbes of ARC Advisory Group. “First, wireless is indispensible for this kind of SCADA project to be cost-effective. Second, end users need to select hardened, industrial, field-proven products to provide a lifelong, reliable wireless solution. Third, a well-designed wireless network can deliver data in a SCADA system with very high reliability, in fact, so high that end-users forget about it.”