The term maintenance includes a wide variety of work activities such as the repair, cleaning, adjustment and renovation of equipment as well as activities designed to improve the working environment such as cleaning, painting etc. Equipment and the workplace should be maintained in a state to ensure they are in good working order, equally measures must be taken to ensure those completing any maintenance activities are protected from the hazards they may face.
Effective maintenance should ensure that equipment can function fully. There are many types of maintenance; some reactive, some proactive.
• Planned Preventative
• Condition Based
Planned Preventative Maintenance – Simple
This is a programme of operation covering inspection, adjustment, rectification of faults and periodic overhauls with the aim of taking action before breakdowns occur. As well as the programme there must be an effective system for ensuring the correct frequency of maintenance is actually undertaken. Records of any repairs and safety issues should be logged and recorded.
Condition Based Maintenance
Condition Based Maintenance is a concept based on the slightly amended premise that ‘if it ain’t broke don’t fix it’. The amendment might read ‘if it ain’t broke and you can prove it don’t fix it.’
Condition based Maintenance or CBM; properly implemented moves away from traditional maintenance scheduling which has always been based on calendar, hours run or similar time related usage measures. CBM will still generate time related maintenance tasks but these will be related to tangible measures of the machine’s condition, ideally be non intrusive (not taking the machine apart) and relate to known failure modes. Checks by taking samples of products, substances or even noise could be used to determine if the equipment is still working correctly.
A condition based maintenance system can only be used on machines that show deterioration in some way and enable the deterioration to be detected before a major failure occurs. A gearbox is a good example where we might expect vibration, overheating, noise as signs of deterioration before it grinds to a halt. A light bulb although it has failure characteristics is over such a short timescale that it is an impractical subject for condition based maintenance (although a lighting system may be suitable).
Is maintenance which is necessary immediately to avoid serious consequences. Due to the pressure involved this type of maintenance can prove more hazardous as time and work pressures may be exerted in order to get the equipment back into working order as soon as possible. This is maintenance aimed at restoring the machine to working order.
“Work Equipment must be maintained in efficient working order“ Provision and Use of Work Equipment Regulations 1998
This could range from fault reporting to planned preventative maintenance. Where it is carried out, records must be kept and it must be carried out safely. All equipment must be maintained in a good condition and in safe working order.
Where machinery has a maintenance log, the employer must keep it to up to date. Not all equipment has to be listed on a log but where there is one required for legal or practical purposes it must be maintained and kept up to date.
SETTING UP A MAINTENANCE SYSTEM
A company will only stay in business and profitability if it produces its product on time and within costs. Breakdowns which may damage equipment, stock and even employees can be costly but not only in terms of money. A damaged production line may mean a customer’s important order is delayed, this could result in financial penalties for the organisation as well as the potential of losing future contracts.
If a member of staff is injured because a machine is running incorrectly and overheats or fails to stop then the company could be sued by the injured party and possibly be prosecuted by the enforcing authority (HSE etc.) if a breach in legislation is identified.
A strategy for effective maintenance will need to be proactive, i.e. allow for planned preventative maintenance as well as emergency repair work. The cost of implementing an effective maintenance system outweighs the cost of not doing so.
When devising an effective maintenance system, the company will need to take into account a range of features to ensure that the system selected will meet the needs of the business. Issues to be considered include:-
• The numbers and types of machines in use
• How complex or simple are these machines?
• What equipment is vital to the work process?
• How easy is it to gain access to the machinery?
• Are the machines used in conjunction with others? – e.g. in an assembly line – as any faults may affect not just the one machine but the whole line.
• Which components are most likely to fail – are spares easily available?
• The workplace – are there any hazards which need to be considered such as heat sources, power sources, radiation etc.?
• Are spare components kept on site?
• Competence of maintenance staff – electrical, mechanical & other.
• Are suitable tools available to enable maintenance to be completed?
• Are permit to work systems in place?
• Are maintenance instructions or manuals easily accessible?
• The age of machinery – older machines may need more maintenance
• The current condition of machines
• Their usage – the machines used most may be more problematic.