During 2002 I toured a diesel-propelled oceangoing ship while it was moored to a dock. When I entered the pilot house I discovered a young woman sitting on a stool before a computer monitor. When she looked up from reading a book I asked, “What’s your job?”
She replied, “Im a machinist mate. I have the engine-room watch.”
I knew about modern sensors and automation and since I had then been working with computers for two decades, I wasn’t surprised. The event caused me to reflect on what it was like when I went to sea sixty-years before.
I imagined that old-time engineers in coal-burning vessels could have reflected the same way had they the opportunity to observe the much improved conditions that existed when I shipped out during 1942 in a twin-screw oil-fired turboelectric ship.
As a cadet engineer I was assigned to the 8 to 12 engine-room watch. In those days before remote sensors, every half hour I made the rounds of the many gauges and thermometers in order to record their readings. Since the mates in the pilot house were responsible for maintaining our ship’s position when we were in a convoy, with a licensed engineer standing by I often acknowledged the orders transmitted by telephone to increase or decrease propeller speeds by just a few turns. I then operated the switches that controlled the motor-operated steam-turbine throttles accordingly.
I wondered also how the machinist mate would have reacted had I told her that during every watch a bag of sawdust was put into the injection of each of the two condensers. The condensers featured Muntz-metal tube sheets and at least five-thousand admiralty-metal tubes made from a copper, zinc, and tin alloy.
That composition in combination with a steel shell and seawater flowing within the tubes, was perfect for electrolytic action, that is, ionization of the tubes when electric currents were present. Because of the two huge propulsion motors and the commensurately large generators that powered them, there were strong eddy currents everywhere. The consequence was pinhole leaks in many condenser tubes. These caused seawater to seep into the condensate that was being recycled for reuse as boiler feedwater. The so contaminated feedwater would eventually cause boiler tubes to fail.
The sawdust treatment provided wood slivers that lodged in the condenser-tube pinholes, swelled, and for some time afterwards, effectively plugged many of the leaks as disclosed by salinity tests conducted before and after a sawdust injection.
Whenever the grim-faced Staff Chief Engineer saw me hauling a bag of sawdust, he muttered seriously, “I wish we had horseshit!”
At first I thought that he was making an attempt at a joke. I later learned that the old timers preferred horse manure because the undigested oats in the manure did a better job of plugging the pinholes and keeping them plugged for longer periods.
In my day, the substitution of horse manure for sawdust, was a sign of progress.
Copyright © 2005 (text only) by Louis D. Chirillo