Friday, December 4, 2020

Weekend Steam: How To Light A Battleship's Boilers

 Merle found another great one. This makes a traction engine look like a toy. Thank You Merle!

UPDATE: A personal note to us from John In Philly, who has a great deal of experience working down deep in ships.  Thank You John! 

John in Philly

6:49 AM (3 hours ago)
to David
There is a whole string of pretty good videos about the inner workings of the battleship  New Jersey. 

I spent eight years on active duty in the Navy, and with the exception of two years on shore duty, I worked in ship engineering spaces for all the rest of the time. 
This led to a career working as a civilian employed by the Department of the Navy at the Philadelphia Shipyard. 
I worked there as a Marine Machinist, not a machine shop machinist, I worked as a mechanic in the enginerooms and firerooms of the Navy's ships when they were in the yard. 
I was there from '81 until the yard closed in '95.
About halfway through that time I changed jobs and became a Systems Inspector, that meant that I criticised the work of others, and I had sign off rights for machinery testing. Both jobs were awesome. 
And both jobs included going to sea with the repaired ships and testing the repaired systems all the way up to full power. 
And going full power on a fossil fueled large aircraft carrier is complicated and requires a lot of complicated machinery to work as designed. 
During that time I was in the Active Naval Reserves, spending my drill weekend and two weeks a year being in the Navy.
The boilers on the Iowa class battleships were controlled superheat boilers. 
Let's talk some numbers. 
The operating pressure was 600 pounds per square inch. 
The temperature of 600 pound steam was 489 degree F, and if you want more energy you have to send the steam through the superheater side of the boiler, and use the burners you see on the boiler front to raise the temperature of the saturated steam up to a max of 850 degrees F. 
The temperature of the superheated steam is controlled by the fuel oil flow to the burners, and it is independent of the steam flow. 
Propulsion boiler technology changed post WWII and the boilers on modern steam driven ships don't have boilers with separate superheater burners. The modern boiler sends all the steam through one passage and the superheat temperature is a function of steam demand. 
Normal steam pressure also went up post war, the 600 PSI plants doubled their pressure to 1200 PSI. 

I spent a large part of my working career deep inside the machinery spaces of ships. 

The video sparked some great memories. 


1 comment:

John in Philly said...

He did a pretty good job.
The USS Wisconsin (BB-64) did some time in the Philly Shipyard during her reactivation, and my job as a Marine Systems Inspector meant that I spent a fair amount of time in her engineering spaces.
When she finished her yard period, I had the chance to go on sea trials during her trip from Philly to Norfolk.
Even though it was only three days, it is a wonderful thing to casually mention, "When I was at sea on the Battleship Wisconsin."