Sign 15 - 15MM Loading Plant

The 155-millimeter plant was the first of the three munitions factories to be built and put into operation. The first shell was loaded on July 1, 1918 almost three months after construction began.

This plant had three production lines, each consisting of the same three buildings—one for receiving, one for pouring and filling, and one for finishing. Unloaded shells were delivered to the receiving building where they were cleaned and prepared for filling. In the pouring and filling building, the shells were loaded with explosives. The final steps of labeling and packing for shipment occurred at the finishing building. All three buildings were connected by a gravity-fed conveyor system and a narrow gauge railroad. The conveyor belt was the quickest way to deliver shells between buildings and the start-to-finish process of loading shells was carefully analyzed to make shell production as time efficient as possible.

Each line of three buildings was 750 feet long and the lines were spaced 500 feet from each other. The wide spacing was a deliberately-designed safety measure to protect plant buildings from damage should one building suffer a serious accident or explosion. Of these structures, the pouring and filling building had the greatest potential for explosions, so it was made with brick and concrete walls throughout. Toilets were conveniently located near each structure and a change house served each line. Four lines were planned for the 155-millimeter plant, but only three were completed by war’s end in November 1918. Construction on the fourth line never began.

155-millimeter shells were a little more than 6 inches in diameter. Each contained 14 and one-half pounds of explosives, weighed about 95 pounds, and had a firing range of 7,000 to 10,000 yards. These and 75-millimeter shells were the two most common sizes used on European battlefields, particularly in mobile field guns. Of the three plant complexes, the 155-millimeter plant was the best-documented through historic photographs.