Tuesday, February 09, 2021

Thanks to Harry for sending me these photos, and teaching me about a type of rail car I've never heard of before, submarine hot metal cars, as the glory days steel industry in the USA was wiped out before I was in high school

The hot metal car was one of the most specialized rail cars ever built. The hot metal cars transferred molten iron from the blast furnaces to a basic furnace, where it would be transformed into steel.

 The molten iron was poured into an open hatch on the car and then a plant switcher moved it to the pouring point. The car was operated by power cables, which were plugged into the car's electric motor. The hot metal runs were operated inside a single yard, however there were few cars that moved between separate plants. 

The B&O had a run that operated between Hamilton and Middletown, Ohio. The iron would remain molten up to 24 hours in the specialized car. The hot metal cars were also known as bottle-cars, torpedoes, and ladle-cars.

The hot metal cars were built with a thick metal plate and were lined with firebrick. They were extremely heavy and difficult to maneuver.

The larger hot metal cars had 16-wheel trucks and if they were completely full could, weigh 400 tons.

The submarine style hot metal car could be tipped without the need for a crane by an onboard motor.


Steel production in the United States peaked at 111.4 million tons in 1973, and declined slightly to 97.9 million tons in 1978. By 1984, steel production collapsed to just 70 million tons.



  1. I found this post particularly interesting. I have lived in Hamilton for almost 50 years. Armco Steel was the major employer in Middletown for decades. They operated blast furnaces and rolling mills at a large complex in Middletown. I am not aware of any site in Hamilton that would have had a use for molten steel. There was a huge Fisher Body stamping plant in Hamilton until sometime in the 1980's but I am pretty sure they did not do any production of sheets or rolls there.

    I am familiar with the "bottles" used to transport molten steel. I worked on the B&O Railroad one summer in the 1960's. Some of those jobs were at Youngstown Sheet and Tube. They operated blast furnaces there. They had their own trains that hauled the molten "slag" away from the furnaces and dumped them in the outer reaches of the plant. This was done in open top ladle cars. Any B&O crews working there knew to keep their trains and personnel clear of the ladles as they were prone to splash molten slag out of the open tops.

    The "bottles" would bring in molten steel from blast furnaces operating in Warren Ohio to the mill in Youngstown. Those were short trains made up of four or five bottles. They seemed to have the right of way over any other rail traffic. B&O crew members looked out for each other and alerted coworkers when bottles were coming. You wanted to be clear of their path as the heat radiating from those trains was awe inspiring.

  2. I live in Watertown NY just below the Canadian border. You frequently see trucks hauling insulated vessels like that full of molten aluminum. I was doing some business at the General Motors plant in Massena MY where they made aluminum cylinder heads for one of the smaller GM engines. They actually purchased they're molten aluminum from someone in Canada across the border and there was an Alcoa plant less than a half mile down the road from them? I guess it's all about cost. The plant manager told me when they arrived they checked the molten aluminum's temperature. If it wasn't hot enough they would reject it and send it back home across the border.