Why combine mechanical integrity and reliability together as part of the same audit?
Without focusing and understanding the design standards a cement plant was originally built to at the beginning of its operating life, many issues are overlooked later on when reviewing a plant’s reliability performance and the decisions tree of whether to repair or replace components. Therefore, assessing the mechanical integrity of equipment is an essential foundation for improving reliability performance. For items such as pressure vessels, inspections are mandatory. However, for much of the equipment that makes up a cement plant, there are no such compulsory inspections. As part of a reliability audit, strategies and improvements can be developed for maintenance planning, maintenance inspecting, measuring and monitoring, in addition to actually implementing maintenance activities. However, consideration to the original design standards and factory acceptance test information is often overlooked. The result generally always leads to some form of catastrophic failure to a major component within a cement plant. Really looking at the original design standards for materials, welding standards, stress calculations and finite element analysis can reveal vital clues to improve an area of equipment that has just experienced a catastrophic failure or can even prevent a major catastrophic failure from taking place. The original design standards are an area often overlooked when completing ‘Root Cause Analysis’ of failures by plant personnel.
Specialist auditors have experience of specifying crucial design criteria when ordering a new cement plant, completing factory acceptance test visits, as well as the experience of building new plants from different international suppliers, alongside the experience of maintaining cement plants of various vintages. The skill sets required for each activity are different and this broader experience base offers cement plant owners something extra to help them achieve successful results from a mechanical integrity and reliability audit.
How to start a mechanical integrity and reliability audit
When completing a mechanical integrity and reliability audit, a good starting point is for the auditor to provide independent shutdown support for a cement plant’s major maintenance period. During this period, access to the major components for more thorough inspections is possible, compared to when the plant is operational. The shutdown can be likened to academic examinations in some ways and offers a great opportunity to make a first assessment. To build a relationship between an auditor and the plant engineers and technicians, offering support for some inspections, execution methods and planning support for the following shutdown allows an auditor to gain a good understanding of the existing maintenance standards, philosophies, tools, resources and systems in place. This experience provides a fair understanding of the actual situation at a plant in order to start looking at solutions to improve performance or to prepare to maintain standards for equipment as it increases in age. Being part of the shutdown allows an auditor to assess the plant management’s approach towards reducing the risks of unplanned failure and their attitudes towards designing out defects or any trials/modifications to improve equipment performance.
These first experiences allow an auditor to be part of a cement plant’s journey over the next few years to achieve the balancing act of safe, environmentally friendly production whilst maximising the production of consistent quality cement, trying to reduce production costs and increase plant reliability.
From this first snapshot, experience has shown that whatever a plant is doing, there are always some aspects in terms of achieving reliability targets that can be improved. The challenge is to then work with the management team by identifying the tools, techniques, resources and approach that best suits management’s aims and experience. Such technical discussions lead to a greater depth of understanding of cement plant equipment and great possibilities to implement new systems, maintenance and monitoring techniques and to plan accordingly to prevent major catastrophes.
What are the benefits?
Over the years, in various companies and different size organisations, results have shown that the combination of skills offered by an auditor provides cement companies with something additional that they do not have in-house and avoids the office politics that can be an issue for plant personnel. External auditors are also independent of the historical activities and decisions that have taken place over the years at a cement plant and thus can offer a fresh view when dealing with an existing plant and its performance.
This is one approach of many, but considering and understanding the original design standards of equipment that management have to operate and maintain is important. Combine this capability with the knowledge of how to build and maintain major equipment, alongside an understanding of how and why design standards have changed can only support a quality decision-making process in terms of managing an asset’s lifecycle and achieving reliable business outcomes.
Part 2 of 2. Find part 1 here.
Written by Kevin Rudd, Independent Cement Consultants, UK. This is an abridged version of the full article, which appeared in the September 2013 issue of World Cement. Subscribers can view the full article by logging in.
Read the article online at: https://www.worldcement.com/europe-cis/19092013/mechanical_integrity_and_reliability_audit_part_2_188/