Part II: Back to Basics

April 2, 2014

David W. Spitzer

Last month, I alluded to a complicated problem at a plant where I was a new hire (Flow Control, February, page 12). My recollection is that the issue surfaced during the second week that I worked in the plant when my immediate supervisor and my (only) electrical/instrumentation foreman were both coincidently on vacation, so I carried the radio.

It was a warm day in June when I was called out to the unit at about 2 p.m. after a shutdown due to low reactor feed flow. New to the plant and on my own, I had to rely on my knowledge of basics, such as understanding Process and Instrumentation Drawings (P&ID), loop drawings, heat and material balances, operating procedures, safety procedures, hazard reviews, and pump curves to resolve the problem.

When I arrived at the unit, I found the flowmeter installed in a submerged piping leg at approximately waist height above grade. Its corresponding control valve was located downstream and was almost entirely covered with ice. The “midget-maker” was open to allow access to the flowmeter electronics.

“What is a midget-maker?” you might ask. Well, cabinets typically open to the left or to the right, depending upon the location of their hinges. In this installation, the cabinet was installed with its hinges on the top so it opened upwards and was held open by a precarious-looking metal brace. The technicians referred to this cabinet as the “midget-maker” because if the metal brace became dislodged while a technician was working on the flowmeter, its door would fall onto the technician and make him “shorter”—hence the “midget-maker” nickname.

I probably don’t have to say (but I will anyway) … cabinet hinges should be located on the left or right; not on the top or bottom. More next month …

David W. Spitzer is a regular contributor to Flow Control magazine and a principal in Spitzer and Boyes, LLC offering engineering, seminars, strategic, marketing consulting, distribution consulting and expert witness services for manufacturing and automation companies. Spitzer and Boyes is also the publisher of the Industrial Automation Insider. David has more than 35 years of experience and has written over 10 books and 300 articles about flow measurement, instrumentation and process control.

David can be reached at 845 623-1830 or www.spitzerandboyes.com. Click on the “Products” tab to find his Consumer Guides to various flow and level measurement technologies.