Delivering Mission Critical data over a Wireless network for Monitoring and Control of Oil and Gas wells in Alberta Canada
Driver
Murphy oil was looking for a network to monitor and control PLCs and to provide drive up network access for field personnel.
Requirements
Hazardous location: Oil and gas field equipment operating in a potentially explosive environment requires that the equipment be rated Class 1 Div 2 for hazardous locations.
Rugged
The environment calls for severe temperature variations, humidity extremes and frequent “brown outs” in an outdoor uncontrolled environment.
Reliable
The equipment should have very a high MTBF as it will transport mission critical control data.
Solution
RuggedCom’s RuggedRated™ RS900W line of wireless switches combine wireline switching capability with 802.11i based wireless extensions, ideal for creating secure wireless networks in harsh environments.
Company Overview
Murphy Oil Corporation is an international oil and gas company that conducts business through various operating subsidiaries. Canada’s Northern Alberta region is one of the most rugged environments in the world, with temperatures easily reaching -40 degrees in the midst of the Canadian winter.
Murphy’s Oil’s installation in Northern Alberta consist of a main oil processing facility with several multi well pads within a 20 Km radius. Each multi well pad is a cleared area approximately 250 m by 250 m. The area is heavily treed as is typical in Northern Alberta.
Field engineering was looking for a solution to connect up PLCs (Programmable Logic Controllers) at each well pad and provide access to field personnel from their laptops to critical monitoring information such as downhole speed, torque, current draw, power usage, and other relevant pump data.
Murphy oil chose RuggedCom’s wireless Ethernet platform, the RS910W, as the core switch for the network. The switches are used to provide access to the control networks of the individual wells and to connect to the main switch for the pad control network.
Setup
At each location, the wireless switches are enclosed in either fibreglass or metal weatherproof enclosures. At the locations where the wireless switches are mounted in a metal enclosure, a single omni antenna, has been mounted outside the structure.
The equipment hardwired to the switch consists of two Ethernet capable PLC processors and a point to point radio which sends data back to the main facility. In order to gain access to the networks, the field operators bring a laptop to the site which connects to the RuggedCom wireless switch and displays the site control information.
Range
Operators easily connect to the wireless switch from all points of the mutli well pads. In most cases this is up to 250 m, although there are instances of connectivity up to 500m in to the surrounding heavily treed areas.
Performance
The switches are operating in some of the harshest conditions on the globe. They are required to operate in extreme temperatures (-40°C to +40°C), bad power (significant number of brown outs and black outs), and humidity extremes.
“We have six switches that have been in operation for over a year and five that have been in operation for approximately 6 months. In that time, there was a case of intermittent communication. It was later determined to be due to a faulty PLC. While determining the cause of the failure, the logs from the RuggedCom switch provided more useful information than the PLC that was faulty and greatly aided in the resolution of the issue”, said Kirk Brost field engineer, Murphy oil.
Application
In this network, RuggedCom’s RS910Ws are used to monitor speed, torque, current, and other crucial pump data. In addition, since the network provides the only connection back to the main PLC, it is also used for control. “Since the control data will manage parameters like tank overflow, the network can’t afford to be down. It is mission critical” said Brost.
Key Features
Given the sensitive nature of the data transmitted over the air, Murphy Oil needed to ensure the platform supported the highest level of security. With 802.11i, the RS900W tightly controls authentication through 802.1x and protects the data through AES-CCMP encryption. These features ensure that the network can’t be accessed by rogue nodes and the data over the air can’t be understood by eavesdropping. Murphy Oil made use of the RS910W’s automatic time synchronization to produce meaningful event logs, important in such a remote location. “In the future, we plan to use the Modbus feature to monitor the switch in real time from the main facility. We are yet to implement this feature as the reliability of the switch has been so good that real time monitoring has not been a priority” added Brost.
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