Maintenance is the periodic implementation of normal, generally minor, actions that ensure longevity of infrastructure assets in line with their design and operational requirements. What is the difference between corrective and preventative maintenance?
PUBLIC INFRASTRUCTURE MAINTENANCE
Infrastructure assets often work in conjunction with one another, in a facility or network, to be able to provide a service. In line with this, financial controls (and accounting treatment such as depreciation) need to be exercised on significant parts of these facilities and networks. Assets and their components are given an expected useful life (EUL), based on their operational and maintenance environment.
Maintenance is a crucial component of successful Infrastructure Asset Lifecycle Management, and includes activities that keep the system in operating condition. Well-maintained infrastructure serves consumer needs and underpins economic production, employment, taxes and rates.
Poor maintenance of public infrastructure:
Shortens an asset's useful life
Undermines service delivery
Increases service-delivery backlogsMaintaining assets responsibly allows a municipality to manage its asset landscape in a sustainable manner, as opposed to running everything to failure. Without systematic maintenance interventions, large amounts of capital are wasted on continuously providing new assets.
Moreover, asset failure can have disastrous consequences.
FINANCING INFRASTRUCTURE MAINTENANCE
Funds that are allocated to infrastructure asset management may be divided into:
Operational Expenditure: Any normal actions required for an asset / asset component to achieve its expected useful life.
Capital Expenditure: Any replacement of assets / asset components (reflected in the asset register).
A Maintenance Plan should consider the regular replacement of equipment, such as pumps and motors. However, in the maintenance management context, which is in line with financial regulations that municipalities are beholden to, the maintenance activities do not include:
Assembly of new assets
Alteration and expansion of existing assets to accommodate a change of function
CORRECTIVE VS PREVENTATIVE INFRASTRUCTURE MAINTENANCE
Corrective and preventative maintenance are two types of maintenance interventions that municipalities should consider in providing competent asset care.
Corrective maintenance is carried out after fault recognition with the intention of returning an item to a state in which it can perform a required function. Maintenance interventions include emergency repairs, as well as unscheduled repairs based on inspection or customer complaints.
It has been estimated that corrective maintenance can cost three times more than the same repairs done under a preventative maintenance regime.
Preventative Maintenance comprises the replacement of components or overhauling of assets at a fixed interval. The aim is to avoid expensive repair and corrective activities resulting from premature equipment damage or failure, and that lead to unscheduled downtime.
In most cases, this approach takes the form of time-driven tasks performed to maintain a level of availability and reliability, but it may also be triggered by monitoring conditions.
Interval-based preventative maintenance is carried out in accordance with an established time schedule or number of units of use and can be guided by supplier manuals or experience.
Condition-based preventative maintenance involves inspection of assets. Testing and parameter monitoring can be applied to determine maintenance needs and requirements.