A new compact, multi-channel controller with
touch-screen display is now available, which is
ideal for the simultaneous measurement and control
of a wide variety of process manufacturing applications

The CMC-99 controller from Impress Sensors & Systems Ltd provides an incredible variety of input and output combinations to suit individual customer requirements. The three card slots on the reverse of the controller each comprise 16 I/O pin options, which enable the user to choose any combination of inputs and outputs to suit the application. For example, up to 48 analogue current or voltage inputs could be used; up to 16 relay/SSR outputs; 24 thermocouple inputs; or 12 RTD inputs; or a combination of these. The unit also incorporates a 24V DC digital input, enabling relays and triggers to be set up.

The CMC-99 controller provides an incredible variety of input and output combinations to suit individual customer requirements.

The CMC-99 is low cost compared to existing alternatives on the market and is ideal for a wide range of process applications, including centralised temperature measurement and control; multi-zone heating control; intermediate pumping station control; spraying and heating control for greenhouses; control of industrial furnaces and incinerators; and for engine test cell measurements.
 
Measuring just 96mm x 96mm x 100mm, the controller housing is very compact, which means the unit can be installed in restricted spaces. The controller has a 3.5-inch backlit colour TFT display and is based on the Linux operating system, with touch-screen menu navigation, offering ease of use and familiarity to the operator. A USB interface is provided on the front of the device, enabling the user to upload or download software programs quickly and easily via a USB memory stick.
 
PID Control
The controller is available in two power supply versions, 230V or 24V AC/DC. An auxiliary 24V DC/200mA supply output on the back of the unit enables external sensors and actuators to be connected and powered by the controller. The CMC-99 can also act as a PID process controller, providing a reliable control loop feedback mechanism for a variety of process temperature and pressure control applications. 
 
The CMC-99 also comes with a number of communications interfaces, including two RS485 ports, two RS232, a second USB Host and an Ethernet connection, allowing the controller to integrate easily with the customer's existing process control networks and fieldbuses.
 
The CMC-99's integral software provides the user with archiving, printing and visualisation options. A variety of visual presentation display options for recorded measurements are available, including numerical display, bar graph or needle gauge display.
 
The CMC-99 is also available with a transparent, lockable door to IP42. An IP65 version is supplied with an additional fitted moulded frame.
 
For further information on the CMC-99 multi-controller, view website: www.impress-sensors.co.uk   Refer to page 110

Protective materials and coatings for extreme environments

In harsh operating environments, selecting the appropriate special coating or corrosion-resistant material for a rolling bearing can prolong the life of the bearing, reduce maintenance costs and minimise production downtime.

Demand for rolling bearings that are able to withstand extreme operating conditions is on the increase. This is being fuelled by tighter legal requirements in many industries, an increased awareness of scarce resources and the need for companies to become more energy-efficient. The Schaeffler Group has developed a range of materials and corrosion-resistant coatings for rolling bearings that satisfy these growing demands.

While standard steel bearing materials provide satisfactory corrosion resistance in many applications, for higher performance requirements, highly corrosion-resistant, nitrogen alloyed martensitic HNS (high nitrogen) steels - such as Schaeffler's Cronidur® and Cronitect® steels - are available.

Cronitect®, for example, is a high performance stainless steel that provides maximum corrosion resistance under extreme operating conditions, including dry running applications or when bearings come into contact with aggressive media such as water, salt spray, acids and cleaning chemicals.

Cronitect® is a high-grade martensitic hardening steel based on the consistent refinement of high-grade NIROSteels. Through its unique composition and new thermo-chemical surface layer treatment process that optimises the surface zone and core properties of the base material, Cronitect® achieves an extremely high hardness, providing excellent corrosion-resistance. Even after 600 hours of salt spray testing, the material shows no signs of corrosion.

Cronitect® is suitable for a wide range of applications, including food processing, materials handling, heavy machinery, power transmission systems (gearboxes), hydraulic and pneumatic systems, consumer products and packaging.

In the food industry, Cronitect® can be used across most of Schaeffler's product range, including rolling bearings, linear guides and plain bearings. Here, the use of Cronitect® significantly increases the availability of machinery, providing extended maintenance intervals. For example, bottling plants typically need to replace all their AISI440C rolling bearings that come into contact with cleaning detergents, every four months. With Cronitect® bearings, this interval can now be doubled.

Other food processing applications that already use Cronitect® on rolling bearings and linear guides include meat processing, filling plants, packaging machines, fish processing and poultry production.

In sports and fitness equipment, rolling bearings must provide excellent corrosion resistance, for example, in fishing reels, inline roller skates, cycle fitness machines, sailing equipment and for the wheel hub bearing supports on racing cycles. On fitness machines, friction has to be minimised to ensure smooth running properties. Here, the use of Cronitect® eliminates the need for grease lubrication and complex, high friction seals.

For further information, view website: www.schaeffler.co.uk   Refer to page 83

Rolling bearings keep London Eye turning for 10 years

After more than 10 years of operation, spherical roller and spherical plain bearings from The Schaeffler Group are continuing to ensure that the London Eye keeps turning safely and reliably.
 
The Millennium Wheel has been rotating continuously, day after day, for 10 years and is now one of the most popular visitor attractions in London, as well as a landmark of the British capital. Since opening, the total number of passengers to have used the observation wheel is more than 36 million.

At the centre of the wheel are FAG rolling bearings, originally supplied by Schaeffler in 1999/2000. The wheel, which was constructed using around 1,500 tonnes of steel, rotates with the help of two FAG double row, radial spherical roller bearings, which are fitted as a locating and non-locating bearing set at the hub of the wheel.

At the centre of the wheel are FAG rolling bearings, originally supplied by Schaeffler in 1999/2000.

Firmly located on the shaft, the locating bearing has an outside diameter of 2.66m and weighs 6.3 tonnes. The non-locating bearing, which has an outside diameter of 2.62m and weighs 5.2 tonnes, moves back and forth on the shaft in order to compensate for thermal expansion. These two spherical roller bearings have a rated life of more than 50 years.

Experienced engineers from FAG Industrial Services carry out regular inspections to ensure defect-free, reliable functioning of the bearings. These checks include endoscopic inspections of the raceways and rolling elements in order to ensure early detection of any problems. Lubricant samples are also taken at regular intervals to check for particulates and abrasion.
 
If at any point during the Wheel's lifetime, the bearings require dismantling, Schaeffler has devised a novel, cost effective, time-saving solution. As the non-locating bearing has a larger bore (2.1m) than the locating bearing (2.04m), it can be pulled over the locating bearing seat, enabling both bearings to be dismantled from one side. Dismounting would be carried out on the river side, as the observation wheel only has a support on the land side.
 
As well as supplying bearings for the central hub, Schaeffler also provided large ELGES spherical plain bearings that hold the London Eye in an upright position. During the original installation of the wheel, these spherical plain bearings enabled the wheel to be moved from its horizontal mounting position across the Thames and into its final vertical position. Since installation, the function of the bearings has been to compensate for micro-movements caused by the wind.
 
Schaeffler has also supplied spherical roller bearings for other observation wheels around the world, including the Beijing Wheel in China. The Beijing Wheel is 208m high and the bearings supplied have an outside diameter of 3.2m, a bore of 2.6m and a ring width of 630mm. Each bearing weighs more than 11 tonnes.
 
For a free copy of Schaeffler's new, 1100-page technical compendium on large size bearings (catalogue GL1), e-mail: info.uk@schaeffler.com or view website: www.schaeffler.co.uk    Refer to page 83