Warwick Manufacturing Group (WMG) is part of the Engineering Department at Warwick University, specialising in research into manufacturing control systems and processes for mass-production environments such as the automotive industry. As such, WMG has a number of automation cells that are, just as with a production facility, sometimes run in manual mode and sometimes fully automatic. Despite the academic nature of the establishment, WMG is still subject to the same health and safety legislation as industry, so appropriate measures have been taken to ensure the safety of personnel working on the automation cells and any visitors who may be in the vicinity.
As well as undertaking research into efficient manufacturing techniques with automation equipment, WMG has also implemented state-of-the-art machinery safety equipment. Nonetheless, Dr Ken Young, Principle Research Fellow, recently decided that a second opinion should be sought on the machinery safety aspects of the major automation cell. He felt that a validation exercise would be very worthwhile, as a 'fresh pair of eyes' almost always sees things that are missed by those who have day-to-day contact.
Pilz Automation Technology was asked to do the work due to its considerable experience and knowledge of industrial machinery safety. The consultants started by carrying out a risk assessment on the cell that contains three robots. As the cell is used in an educational and research establishment, where access to the hazard zones is more frequent than that normally expected in an industrial environment, coupled with the fact that it houses three high capacity robots, category 4 according to BS EN 954-1 was chosen. The results of this risk assessment were then used to make a series of suggestions for improvements.
On the whole, WMG had already identified the major risks and taken suitable steps to reduce the risks to an acceptable level. However, the consultants made several suggestions relating to housekeeping and documentation. Other suggestions were made for modifications to be carried out on the safety equipment, but these will not be costly to implement. For example, the cell is very large, and to prevent possible problems a pre start warning alarm is to be installed to give a warning to any personnel working inside the area before the operating mode is switched from manual to automatic mode (to give time for the trapped person to reach an emergency stop button). This will supplement the existing standard operating procedure that instructs the operator to carry out a visual check of the cell before selecting automatic mode.
Because of the frequently changing nature of the automation cell, there has sometimes been a reluctance to document fully all of the working practices and safety-related control systems. Nevertheless, the consultants pointed out that WMG must do so in order to comply fully with the relevant health and safety legislation.
Dr Young is very satisfied with the consultants' work, saying: "It was definitely worthwhile; we have now identified some areas where we need to make improvements. Moreover, several of the lessons learnt can also be put to good use in other areas of our labs, not just the automation cell that was studied. It is doubtful that we would have identified all of the hazards if we had done the risk assessment ourselves, which shows that we were correct to employ external consultants."
At the conclusion of the project, WMG was presented with a comprehensive package of documentation. The risk assessment includes a complete list of risks and highlights where controls are adequate and where improvements are required - for which suggestions are made. Guidelines for housekeeping are also appended to assist WMG with bringing this area of its activities up to standard.
Machinery safety consultancy is just one of the services available from Pilz. Others are engineering and training. Under these three broad headings, Pilz can assist companies and organisations with virtually any aspect of machinery safety, however simple or complex.