Thread: Machines
View Single Post
Old 02-12-2017, 08:10 AM   #112
xoxoxoBruce
The future is unwritten
 
Join Date: Oct 2002
Posts: 71,105
The biggest reasons were the precision and strength of materials allowed higher pressure steam. There are three sections in modern steam turbines, the steam goes through the high pressure section, then the medium and low before it's condensed and pumped back to the boiler. The lower the pressure the larger the blades.

EPRI(Electrical Power Research Institute) funded by all the power companies in the country, had a test turbine at PECO's Chester station running 5,000 psig steam(close to 1,000 deg F). Just to add a pressure tap or thermocouple was a major pain in the ass because the wall thickness of the pipe was over three inches of high strength steel. Drill the hole, then follow a strict procedure to weld in the tap with each layer of weld inspected. Lastly make sure there is NO chips or slag on the inside of the pipe to become missiles when restarted as they would wipe out blades at that speed.
__________________
The descent of man ~ Nixon, Friedman, Reagan, Trump.
xoxoxoBruce is offline   Reply With Quote