Mining application: High-security Ethernet switches for data control

By Control Engineering Staff March 8, 2007
Designed for harsh environments, these fast, high-security Lynx Ethernet switches from Westermo have a 20 ms reconfiguration time, the world’s best off-the-shelf performance for Ethernet switches, company says. This mining application has a full industrial Ethernet redundancy ring that monitors and controls the facility.

Fast, high-security Lynx Ethernet switches have a 20 ms reconfiguration time, and offer the world’s best off-the-shelf performance for Ethernet switches, according to Wedron Silica in a mining application. A redundant industrial Ethernet ring monitors and controls the mining facility using Westermo’s high-security Lynx switches for harsh industrial environments.

Fairmount Minerals is one of the largest U.S. producers of industrial sand. Its Illinois-based subsidiary, Wedron Silica, has been in operation for over 100 years, producing high-purity, round-grain silica sand. This sand is mined from the St. Peters Sandstone, a 200 million-year-old sand deposit that runs from Minnesota to Oklahoma. More than 50 hourly and 10 supervisory personnel manage the production of approximately 10,000 tons of sand daily. The Wedron facility’s biggest producing segment is for the fracturing sand market. Hydraulic fracturing sands, known as ‘frac sands,’ consist almost entirely of quartz or silica sands and are used as proppants in oil and gas wells. Frac sand treatment is the forcing of a concoction of frac sands, viscous gel, and other chemicals down a well to prop open fractures in the subsurface rocks thus creating a passageway for fluid from the reservoir to the well.

Hydraulic high pressure mining cannons : Wedron Silica plant operates 24 hours a day, 7 days a week. Production is managed through an industrial Ethernet network that exchanges data from hydraulic high pressure mining cannons. Additionally, data from cameras linked to the control center via fiber-optics help to control and adjust truck loading, as well as the sand drying rooms. Data monitoring and control systems need to be of the highest reliability levels, specifically in such a harsh industrial environment as mining.

‘Our data network has been working using the Ethernet protocol for 10 years, but this is the first time that we have installed a full redundancy ring’ says Frank Barnes, technical manager at Wedron Silicate. ‘There were several reasons for choosing Westermo’s Lynx range of switches, like the strong harsh environment compliancy, the off-the-shelf redundant ring capability, and the world’s fastest data recovery time of 20 ms. Particularly, we appreciate the easy configuration and monitoring of the switches as well as the no-charge software updates. We have also had very close technical collaborations with Trond Grendar from Westermo and Doug Smith of the John R. Willis company, an independent manufacturer’s representative for Gross Automation, Westermo’s distributor in North America,’ says Barnes.

Lynx switches in operation : The ring portion of the network consists of 11 of the Lynx 1400-series switches with 6 Lynx 400-series switches on branch runs. The ring switches are located in the plant process buildings and are named for their location. All are mounted in dust tight boxes and powered by two 24 V dc power supplies connected to a battery backup. The ring network is kept powered for more than 2 hours in the event of a power outage. All control and monitoring information is passed on Westermo’s network.

Hydraulic high-pressure mining cannons do their part in mining 10,000 tons of sand daily from at this Wedron Silica site in Illinois.

Westermo’s L1400 and L400 support IMGP protocol (Internet group management protocol) provides filtering techniques to control the flow of data around the ring in such a way as to optimize bandwidth, and secure network operation. IGMP is used by IP hosts to dynamically register membership in multicast groups to the closest multicast router. Multicast routers periodically send out a ‘Host Membership Query message’ to remain updated on group membership for the local network. To efficiently use bandwidth and cut down on traffic, multicasting is the ideal solution. When data needs to be sent to a many users on the network, the data will be sent simultaneously to the specified users via multicasting, and not just blanketed to all users. IGMP snooping requires the switch to examine, or snoop, some Layer 3 information in the IGMP packets sent between the hosts and the router. When the switch hears the IGMP host report from a host for a particular multicast group, the switch adds the host’s port number to the associated multicast table entry. When the switch hears the IGMP leave a group message from a host, it removes the host’s port from the table entry. The Lynx-series has the IGMP Server (router) implemented, which means that no external IGMP server on the network is necessary. It is also integrated with the FRNT feature, which means that the multicast filters will be updated within 20 ms in case of network failure.

Quality, scheduling, determinism : The Lynx switches fully support QoS (quality of service) with four priority queues and strict priority scheduling as well as HoL (head of line blocking prevention). This is also a key issue for process applications such as Wedron’s, because it achieves determinism for real time critical applications. The 400 and 1400 Lynx switches have a military design with a full metal housing (IP40). They operate under a wide temperature range from -40 to +158 °F and have a wide dc power range from 19 to 60 V dc. They have no moving parts or electrolytic capacitors, low power consumption with redundancy, are DIN rail mounted and support long cable.

‘This first successful implementation with Westermo’s flagship line of Lynx switches will probably lead to many new business opportunities inside the group,’ sums up Frank Barnes. ‘This application positions Westermo as the industry leader in complex network management for harsh industrial environments—all this while remaining cost-effective against possible competing technologies,’ adds Bob Gross, president of Gross Automation, based in Milwaukee, WI.

Fairmount Minerals, based in Chardon, OH, is one of the largest U.S. producers of industrial sand. The high-purity (>99.5% SiO2) sand ranges from coarse (21 AFS/GFN) to very fine (125 AFS/GFN).

Westermo Teleindustri AB is a Swedish company created in 1975, with about 140 employees.

Gross Automation, a Westermo distributor , specializes in industrial automation components from European and domestic suppliers.

Edited by Mark T. Hoske , Control Engineering editor in chief