Networks and Communications
ControlNet Backbone at New Rover Paintshop
When the Rover management team took the decision to invest in a new paint plant, Rockwell Automation control and automation systems were specified by paintshop specialists Durr at Warwick for what was to be a multi-million pound state of the art installation.
The brief was to provide a paint plant using the latest technology and keep installation costs to a minimum. The turn-key contract was for a flexible facility capable of painting a wide range of vehicle models, both large and small.
The control and automation systems are the backbone of the installation and needed to be carefully selected to ensure they support the high specification of the rest of the plant. Durr specified Rockwell Automation as partners for this project.
George Laing, software systems manager for Durr says, " The selection of Rockwell Automation as the supplier of control and automation equipment was critical. They were specified to supply Allen-Bradley ControlGear, PLC controllers, Industrial PCs, Overhead Displays and a Networking System. With such a complex project, support is very important and Rockwell Automation provided everything we needed. This included a dedicated applications engineer whose product knowledge and experience made an important contribution to the project."
Durr had installed many systems over the years using traditional point-to-point I/O connections. However, Durr were looking to technology to reduce costs and the decision was taken to install a ControlNet network throughout the plant.
ControlNet offers a high-speed open network for transmission of time critical application information.
ControlNet provides many benefits including a modular design that is easy to install and commission. The cabling infrastructure is dramatically reduced, providing sizeable savings in installation hardware -- for example, a typical 60% savings in control panel suites. Reduced cabling not only saves cable cost but also other items such as trunking and brackets. These savings are compounded with reductions in both installation man-hours and commissioning time.
At Rover's Oxford facility, these savings are in the order of 50% as compared with a similar project using traditional methods. A further benefit of the reduced cabling is a far neater installation that is much easier to manage and trouble shoot. Smaller areas are required for the control equipment and the resulting savings in space can be put to more productive purposes.
John Painter is the Rover engineer responsible for the control systems in the new plant. "The decision to use ControlNet has been fully justified, with the system proving to be reliable and easy to use. Detailed information can be obtained about the process in any part of the building down to the status of individual motors, drives and control components. Access to the data can be from the central control room or anywhere on site using the Allen-Bradley PanelView graphic displays." With any new system there are issues related to training. John continues "We were initially concerned about training for the process operators. This was addressed with Rockwell Automation providing a training centre where operators could familiarise themselves with the technology in a safe simulated environment."
With such a large investment in this critical area, downtime due to failure of control equipment would be a serious problem. John needed to be sure that replacement products would be readily available. "Rockwell Automation has established a bonded store of essential products. If a failure occurs we can access this stock and have the replacement product installed with a minimum of downtime."
The existing paint shop at Rover in Oxford was nearly 20 years old and used old technology. The plant was both slow (taking about 14 hours for a car body to pass from one end to the other) and would not meet one of Rover's key strategic environmental goals to progressively reduce solvent emissions.
The new plant was to be the first in the UK to use the very latest waterborne paint shop technology. This pioneering technique was developed with the help and support of paint manufacturers PPG and results in a particularly efficient and clean process with minimal emissions.
The paint process is based on the Durr ECO product family, which provides complete finishing to the car body in a highly automated process taking less than 6 hours. This includes body preparation and seam seal, primer coat, base coat and a two component clear topcoat. Each coat is oven cured with air jets and a feather duster process ensuring that all dust particles are removed prior to the next painting station. A final paint quality and inspection area ensures each body is carefully checked before being passed to assembly.
Minor blemishes can be polished out at this point with more serious defects requiring the body to pass through the paint process again. The consistent high performance of the plant has significantly improved productivity with over 94% of bodies being right first time.
The throughput of the plant is currently 35 bodies/hour, with a potential capacity of 60 bodies/hour. Up to 600 car bodies can be accommodated in the facility, which has two marshalling areas. Each body is fitted with a unique identification tag allowing its progress through the plant to be logged. The system automatically groups together bodies which are to have the same finish in one marshalling area while a second marshalling area at the end of the line groups bodies in respect of body style or trim level.
The 'Greenfield' project was started in 1996 with the plant commissioned and handed over in September 1998. The new paint shop has been a great success with completion on time and within budget. The project represents the very latest in paint shop design incorporating innovative 'cutting edge' technology. There were firsts in respect of the use of waterbourne paint technology and ControlNet to provide the control and communications infrastructure.
For further information, please contact:
Rockwell Automation Ltd
Pitfield, Kiln Farm
MILTON KEYNES, MK11 3DR
Tel: 0870 242 5000
Fax: 01908 839696
Technical: Mark Daniels
Product Manager - ACIG
E-mail: mdaniels@ra.rockwell.com
General: Jennie Holmes
Marketing Communications Manager
E-mail: jholmes@ra.rockwell.com
Sales Leads: Rockwell Automation Response Centre
DBI
31A Chelsea Wharf
15 Lots Road
London SW10 0QJ
Issued by: Fisher Industrial Marketing
Kingfisher House
54 Banstead Road
CARSHALTON, Surrey, SM5 3NW
Tel: 0208 643 0240
Fax: 0208 770 9511
E-mail: info@fishermarketing.co.uk
Ref: June, 1999