One doesn't have to do too much research to establish how old reciprocating compressor technology really is. If steam turbines ushered in die Industrial Revolution over 200 years ago, reciprocating compressors couldn't have been far behind. On a visit to an Iowa-based equipment manufacturer in 1989, I was amazed to see how a 1908-vintage reciprocating compressor satisfied their around-the-clock plant air requirements dependably and efficiently. Eighty years with nothing but routine, albeit conscientious, "tender loving care" maintenance!
What an endorsement of the skill of the original designers, machine builders, and generations of maintenance craftsmen. It's only fair to say that the old turn-of-the-century compressor was designed with greater margins of safety, or strength, or capacity to survive abuse than today's higher rotating speed and higher linear piston velocity reciprocating machines. Many of today's compressors are likely to have been designed with the emphasis on reduced weight, less floor space and, let's face it, least cost. The concepts of maintainability, surveillability, and true life cycle cost are too new to be taught in modem universities and engineering colleges.
The reward system for project managers, process design contractors, and project engineers is largely based on capital cost savings and rapid schedules. Regrettably, even the commitment to maintenance excellence of many of today's managers and mechanic/technicians is not always as sound, or as rigorous and consistent, as it perhaps was a few decades ago. Today, everyone speaks of reliability, but many of these well-meaning folks seem to be "forgetful hearers" instead of "doers." There are precious few instances where the maintenance or reliability technician is given either the time or the training to determine the true root causes of equipment failures. Scores of workers are instructed to find the defective part, replace it with a new one, and get the machine back in service.
But the part failed for a reason, and if we don't find the reason for its failure, we are certain to set ourselves up for a repeat event. Whenever we rush a maintenance task, we are likely to omit taking the types of measurements that are critically important to the achievement of ran length extensions and increased reliability and safety. What is needed is more attention to detail; the notion that equipment reliability can be upheld by fixing only those components that are visibly defective may not always be correct. There may be compelling reasons to call for a restoration of all fits, clearances, and dimensions to as-designed values.
This takes time and planning. It requires access to authoritative data and a fundamental shift away from business-as-usual, quick-fix, or big-picture attitudes. Time and again we have seen reciprocating compressor owners/users engage in the search for the high technology solution. When a succession of broken valves is encountered, the hunt concentrates on better valve materials instead of the elimination of moisture condensation and flowinduced liquid slugging. When piston rods wear unevenly, some users pursue superior metallic coatings, but close their ears to the possibility of tolerance stackup being the real culprit.
This progressive move towards out-of-roundness or not-so-perfect perpendicularity of mating parts could well be the root cause of equipment distress and would have to be rectified before it makes economic sense to install components with advanced configurations or metallurgical compositions/And we might add that it wouldn't hurt if someone took the time to carefully read and implement the original equipment manufacturer's maintenance manual.
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