Viewing Maintenance as a system to optimize performance
In 1958, Mao Zedong of China ordered all sparrows killed because they were eating grain necessary for people, and he thought killing the sparrows would result in surplus food for 60,000 people. This campaign seemed successful, as the sparrow was nearly made extinct in China. Unfortunately, Mao did not realize that sparrows were natural predators to locusts and other insects. With the sparrows gone, the locusts multiplied, devastating Chinese agriculture. The ecological imbalance helped spur on massive food shortages and the death of an estimated 30 million people.
Why did this happen? Mao didn’t have an appreciation of a system which maintained ecological balance. Once upset, the unintended consequences resulted in millions of deaths.
Ecological systems and their mismanagement are only one facet of the study of systems. Systems or systems theory is an interdisciplinary field that studies the nature of systems—from simple to complex—in nature, society, engineering, technology and science. Some areas of study include systems engineering, systems analysis and systems thinking. This article will focus specifically on how systems concepts apply to the maintenance organization and why we should be concerned about it.
What is a system?
A system is a group of interacting or interrelated entities that form a unified whole. A system is delineated by its spatial and temporal boundaries, surrounded and influenced by its environment, described by its structure and purpose and expressed in its functioning. Systems are the subjects of study of systems theory. ¹
From this we can assume a system is comprised of smaller subsystems with a purpose or goal. Systems science can apply to a business or organization.
Blanchard defined system as “…a set of interrelated components working together with the common objective of fulfilling some designated need”. 2
When applied to businesses, we can conclude that these “components” are working together to produce something of value to the user, and that their efficiency and effectiveness are dependent on how well they work together. If a system is inadequately designed or poorly connected and integrated, it most likely will be unable to achieve its goals.
Symptoms of broken systems:
Silo mentality: an inward mindset that resists sharing information/resources with others
Processes plagued by waste and inefficiency due to poor workflow design, broken customer/supplier relationships and poor decision making
Variability in meeting customer requirements due to poor system design and standardization
Components or subsystems of an organization are not aligned with a clear purpose, characterized by inability to execute strategy and lack of understanding of what matters to performance.
These symptoms can lead to financial ruin.
Business systems are frequently identified by department names: Procurement, Engineering, Finance or Human Resources. Their workflows, connectivity and relationships result in producing something of value. If their workflows, connectivity and relationships are optimum, the value they produce should meet or exceed the goals of the business.
Systems and processes are the essential building blocks of a company. Every facet of business - storeroom, workshop, production - is part of a system that can be managed to produce something of value. The details of each business system vary by company, but the fundamentals remain the same.
The Key Concepts of Systems:
1. Systems are composed of interconnected parts
2. Inter-connected parts are interdependent
3. Every system has an aim
4. The structure of a system determines its behavior
5. How well the parts cooperate to support the aim determines how efficient and effective the system functions
6. Ultimately we seek synergy in which “the whole is greater than the sum of the parts
Is Maintenance a System?
Based on definitions, maintenance is a system: usually a subsystem of the corporation, made up of a collection of elements organized to achieve a purpose. How well the elements are integrated and interact determines the efficiency and effectiveness of the maintenance system.
Figure 1 is a simple depiction of a system view of maintenance. The maintenance objective will reflect and align with corporate and plant objectives, considering the plant structure, while defining equipment strategies for ensuring the level of reliability required. Equipment strategies will define spares policy and outline resource structure needed to plan, schedule and execute the workload. The administrative structure will define and support personnel policies and determine budgets/controls to manage costs. Subsystems will be reviewed/improved to optimize their contribution to the systems aim and goals: achieving the desired level of reliability while meeting cost and safety targets.
Figure 2 depicts maintenance as a system. This example shows how three sub-systems working as a system contribute to achieving optimum inherent availability. Three subsystems in this example are materials management, resource management, and reliability management. Materials management and resource management aid in optimizing the repair process. Both subsystems are critical in identifying and procuring spares required for the repair, planning/scheduling the repair, and mobilizing the resources to complete the repair. To ensure repair is made in the shortest time and at the lowest cost, information and communication must flow seamlessly and continuously between the two subsystems. The metric used to measure the repair process is ‘mean time to repair’ or MTTR.
The third subsystem in the maintenance system example is reliability management, responsible for establishing the equipment strategies for achieving optimum reliability while considering safety and cost. Equipment strategies are defined by manufacturers’ recommendations or a risk based approach like reliability centered maintenance. The metric used to measure reliability performance is ‘mean time between failure’ or MTBF. MTTR and MTBF will be used as illustrated in Figure 2 to calculate inherent availability.
In order to realize the goal, achieving the desired inherent availability, all three subsystems must work together. Achieving a systems aim must be managed with attention to the entire system. When we optimize subcomponents of the system, we don’t necessarily optimize the overall system. Sub-optimization is the practice of focusing on one part of a system and making changes intended to improve that subsystem while ignoring the effects on other subsystems. This will lead to sub-optimization of the whole system leading to waste, delays, and inefficiencies resulting in lost profits and lower plant throughput. Optimizing system performance should begin in the system design phase.
8 Characteristics of a Good System Design:
1. Designed with the customer (internal and external) in mind
• Work products and services are handed off to internal customers who must meet their requirements. The objective is to prevent the internal customer from reworking or worse, passing through product that is fails to meet specifications.
2. Represents your best known way of doing something
• A well defined system should be documented with workflows of each subsystem and where the work is performed and handoffs are made, clearly describing roles and responsibilities.
3. Has one primary aim, goal or purpose
• Primary/secondary goals should be clearly defined and communicated to stakeholders.
4. Has an owner, accountable for/reporting on system results
5. Is as simple as possible, documented, understood by workers, and repeatable
• System users should be trained/coached on subsystems and processes.
6. Has performance standards and results are measured.
• System should be thoroughly implemented and capable of meeting performance standards and goals. System users understand performance standards and can identify out of compliance conditions. Measures are monitored by all team members.
7. Workers get ongoing feedback about system performance and are recognized for good results.
8. Has sufficient focus on system details to eliminate most bottlenecks, inefficiencies, waste, and rework.
Optimizing Maintenance System Performance
These steps will aid in optimization of existing maintenance organizations and system with every process having an input from a supplier and an output to a customer. Process stakeholders understand how they add value to the goal of the system. A robust system will have clear specifications for each product handed off to internal customers along with feedback to suppliers.
1. Process map and document your system
• Identify your processes
• Show how the processes work together to produce value and their interconnectivity
• Ensure roles and process steps are clear
2. Identify your products and services for each process
3. Understand customer/supplier specifications/requirements
4. Identify the suppliers/customers for each product/service
5. Communicate process requirements to suppliers
6. Identify customer specifications
7. Demonstrate the process is capable/meets specifications
8. Achieve a thorough implementation
9. Continuously improve
Summary
The complexity of maintenance systems increases as new technologies are introduced. In today’s environment, there is an increasing need to develop/produce systems that are robust, reliable, high quality, supportable and cost effective. Viewing and understanding maintenance as a system with an aim and purpose, rather than a collection of disparate parts, is the first step in designing and developing a maintenance system that can be managed and optimized for sustained long term performance.
Tracy T. Strawn,
Strategic Advisor,
Marshall Institute