In my Sept. 6, 2021, article for The RAM Review (see article link below), I explained how truly world-class petrochemical and refining companies invested roughly 5% of the cost of equipment in pre-purchase reviews and reliability audits. This week, I am discussing a closely related strategy. (It’s one I have often spoken and written about many times over the years.)
Storing full sets of manufacturing drawings at a local authorized repair facility is an option that many best-of-class companies have exercised over the years. For example, in the 1970s, a world-renowned overseas manufacturer of mechanical-drive steam turbines agreed to place the manufacturing drawings on microfiche and store them near the purchaser’s plant site in the United States. All of this is usually pre-defined and pre-negotiated.
As to accurate P&IDs, these clearly should reflect the as-built plant. Without them, one cannot safely operate a modern facility. The ultimate installation site must have access to these process-related documents and, we believe, this fact is rarely questioned.
On existing heat exchangers and other plant machines, one might consider hiring a competent reverse-engineering specialist and give the OEM a choice: That OEM either works with you or you entrust the reverse engineering and modification jobs (that you have apparently engineered) to others. It’s hard to believe that heat exchangers contain proprietary elements, but some marketers may try to claim otherwise.
BOTTOM LINE: DON’T PUT RELIABILITY AT RISK
Strategies such as machinery-reliability audits and reviews and, as discussed here, those regarding manufacturing drawings and accurate P&IDs can be a tremendously worthwhile investment. That is if they are put in the hands of or supervised by experienced engineers. Of course, this presupposes that a perceptive project manager or owner’s representative will see to it that the resulting recommendations are, in fact, implemented. Consider the following.
Over 20 years ago, an early edition of my book, Machinery Uptime Improvement, noted that a petrochemical project in the $500,000,000 range (typical of the mid-1970s) would optimally staff machinery reliability audits with four engineers for a four‑month period, and staff machinery-reliability reviews with two engineers for a period of 2 to 3 years. At that time, the total cost of such efforts was found to be in the range of $650,000 to $850,000. Although this seemed like a lot of money in 1975, the plant owners contrasted it with the value of a single startup-delay day (say $400,000) plus a potential added cost of two unforeseen days of downtime (which might be accompanied by the loud thundering of two tall flare stacks for most of those hours).
Granted, reliability-assurance efforts made before delivery of machinery are more cost- effective than post‑delivery or post-startup endeavors aimed at the same goals. However, questions may remain how to optimally conduct these efforts, how to man them, and which components or systems are to be scrutinized closely. Here is where the accurate analysis of available failure statistics and a close review of available checklists will prove most helpful.
In the end, a review of the failure statistics of rotating machinery used in modern process plants will also help determine where the owner/operator’s money should be spent for highest probable returns. Moreover, failure statistics can often be used to determine the value of, and justification for, intelligent resource allocation.TRR
ABOUT THE AUTHOR
Heinz Bloch’s long professional career included assignments as Exxon Chemical’s Regional Machinery Specialist for the United States. A recognized subject-matter-expert on plant equipment and failure avoidance, he is the author of numerous books and articles, and continues to present at technical conferences around the world. Bloch holds B.S. and M.S. degrees in Mechanical Engineering and is an ASME Life Fellow. These days, he’s based near Houston, TX.
Tags: reliability, availability, maintenance, RAM, asset management, professional development