Operational excellence is the primary goal of any O&M strategy. But what exactly is it and how can it be achieved?
While an Operation & Maintenance strategy determines the overall approach towards optimising cement plant operations, it should have one overriding goal: operational excellence. There are many different aspects to achieving excellence – some highly tangible and others less so. Overall Equipment Effectiveness (OEE) is one of the key tangible aspects, providing a measure of the cement plant’s ability to produce cement efficiently. OEE can be seen as a meta-KPI, which is itself a multiple of three KPIs:
• Availability factor – the percentage of time in which the equipment can operate, excluding external process factors
• Performance factor – average production rate versus nominal capacity of equipment or its best demonstrated practice
• Quality factor – ratio of production volume complying with quality expectations
Although OEE benchmarks can vary, a goal of at least 85.5 percent should be achievable. But even at this level, each of its three composite KPIs needs to be exceptional. For example, an availability factor of 90 percent, performance factor of 95 percent and quality factor of 100 percent are not beyond expectations.
So how can a cement plant achieve a high OEE? An unrelenting focus on five operational aspects can provide the building blocks for world-class operating efficiency.
1. Minimising risk
It is essential to understand the full impact of the equipment’s function. This involves identifying the probability and consequence of failure in critical equipment. Through methodologies such as condition-based monitoring, the equipment can be monitored and analysed for vibrations, for example.
There are also significant benefits from hot kiln alignments as well as inspections of the mills, stackers and reclaimers, coolers and larger gear units. This will help determine what critical parts need to be replaced as well as any other corrective maintenance activities to bring the equipment back to condition. It is important to note that such analyses can only be performed by specialised, certified technicians who have the necessary skills and experience.
2. Stabilising operation
Here, you need to identify root causes of process instability and variations. Central to stabilising operations is optimising processes and providing on-the-job training associated with the kilns, raw mills, coal mills, cement mills, and fuel handling and dosing.
3. Improving maintenance effectiveness
A “debottlenecking” approach can help improve equipment reliability. This starts with ensuring that downtime is registered properly and consistently and that KPIs are monitored. Then it is important to perform a root cause analysis for any critical and repetitive failures. Based on this, corrective actions can be taken and results measured.
This can be an ideal point to implement a Reliability-Centred Maintenance (RCM) strategy. At the root of RCM are equipment maintenance programmes, operational procedures, and inventories of any refurbishments or redesigns that may be necessary. Two or three teams should be trained in RCM at every plant. RCM-based work procedures for critical equipment should be determined, new procedures implemented and centrally documented, and results measured.
FLSmidth Operation & Maintenance has helped cement plants achieve world-class operations through an unrelenting focus on operational excellence
4. Ensuring spare parts availability
It is vital to have spare parts available for those times when they are needed. In order to understand the requirements for spare parts and any other production consumables, a demand analysis is recommended. This is usually performed by the maintenance department. The procurement department will then perform a supply analysis. Any necessary actions should then be implemented to increase the service level of current inventory management practices.
5. Improving staff competencies
Regardless of the quality of the equipment, systems and methodologies in place, the key to operational excellence is staff competencies. It is crucial to identify any skills gaps amongst key staff in both the production and maintenance departments. Then a training programme can be designed and executed accordingly.
The sum of the parts
Rigorous focus on these five areas is likely to improve operating effectiveness – which in turn will deliver better financial returns. Developing these capabilities is within reach of many cement plants, but can only be achieved with the right strategic mandate and organisation capabilities. Alternatively, owners can look to an outsourcing partner who can provide the necessary technical capabilities and resources at an attractive service level. This can often be the most economically viable route to a successful cement production business – see graph above
* This article is based on an article first published in World Cement