Process Control

Industrial Control Systems
Severn Controls built its reputation on the design and installation of systems for the control of industrial processes of all kinds. The company has developed advanced control technology which can be adapted to a very wide range of applications, from manufacturing processes to flow control.

Recent projects include:

• A chemical dosing system for industrial barrel washers supplied by Henkel Ecolab to a major industrial laundry chain. The system controls the precise metering of small quantities of up

  to 10 cleansing chemicals and calibrates dosing pumps.  A SCADA (computer-aided) package monitors all functions and costs the chemicals used per wash, as well as providing valuable maintenance information.

• The design and manufacture of five variable-speed inverter cabinets (right) to be used by Dupont plc in the production of vehicle airbag material. The cabinets house a number of inverters up to 165 kw, all communicating via Profibus.

Materials Handling
Conveyor and materials handling systems require accurate control to ensure flow is maintained at the optimum rate at all times, with a rapid and appropriate response to bottlenecks or blockages.

Projects include:

• Design and installation of control panels (right) for organic grain millers Shipton Mill Ltd, who produce many tonnes of flour per day in various grades and blends at their Frampton-on-Severn plant. 800 amp mains distribution switchgear feeds four motor control centres containing switchgear and PLC-SCADA equipment.
• The design and manufacture of PLC-controlled multiple variable-speed drive panels for automated conveyor systems used in book manufacturing plants in the USA, Canada, Australia and Europe. The VSD drives allow the conveyors to change speed automatically to match demand. A PLC monitors all stages of the system, facilitating a rapid, measured response to faults, blockages and bottlenecks.
• Conveying dusty materials from process to silos using a vacuum system with exhausters.
• Batch weighing of bulk materials to a predefined and adjustable 'recipe' and blending in a mixer.

Water Treatment

Projects include:

• Flooding used to severely affect a part of the Severn Vale every spring tide (right), when the flow from a small river was pushed back upstream by the tidal River Severn. A tank (concealed underground) containing an automated pump has eliminated the problem.
• Design, installation and commissioning of a land drainage system   for the Lower Severn Drainage Board (right). A 35 cubic metre tank houses a submersible pump with an output of up to 180 litres per second. A variable speed drive allows precise control of pump   speed depending on water level. An ultrasonic control unit monitors the water level in the tank and controls the pump as required,  varying the drive speed to suit demand.