I'm surprised that the "C" model shown has teeth on the bucket. All of our machines, the 992's and 475's, has spade nosed edges with no teeth or adapters. They could not be kept on for digging the pits. In fact, we had trouble keeping the edges on at all. The original Cat machine sealed bucket pins and bushings were removed, the loader arm bores made larger, and extra fat high temperature bronze bushings were installed. They were never greased for obvious reasons. The Michigan loaders received the same treatment.
The water/glycol fluid supposedly gave the operator about 13 additional seconds to evacuate the cab if a hose or something broke and started spraying fluid all over that would catch fire from the immense heat in the still hot or liquid slag. We used DowTherm 209 for the same reason, plus silicone coolant hoses. Doesn't seem like much extra time, but one would be surprised what an operator can do when threatened by being badly burned or killed in a machine fire.
All our tires used the Erlau chains, and all were loaded with calcium chloride. Even so, the slag burned holes in tires with regularity. Our machines also had a lot of counterweight on them. The 992's received a slab 18 inches thick that wrapped around the entire radiator housing and that covered both battery boxes. It weighed about 12000 pounds alltogether. If not used carefully by an experienced operator, our 992’s broke in half very easily.
We were just getting around to installing whole-machine fire suppression systems when the steel economy went to hell in 1980. Up to that time, we had some home-made setups that required the operator to pull the pins from the bottles as he was exiting the machine. As I recall, the company had several burned up machines in a boneyard in Detroit. They also has several dead and severely injured operators in those early days. One ran through a pool of liquid slag to get away from a crawler loader that died and was on fire. The company set him up with his own gas station which he ran for years. His legs were burned off half way to his knees. Another operator was killed when an overhead crane operator dumped a pot full of molten slag behind him in a mill in Detroit. The loader operator burned to a crisp, a fitting end to a man that was having an affair with the crane operator’s wife.
Slag was first removed by hand and horse and mule powered wagons, then early steam and power shovels took over. When Cat first came up with the traxcavator, it was tried and used with some success along with early chain-drive trucks. That trend in crawler loaders continued with what were called “steel mill specials.” The 983 loader started out as a “special.” 977’s were a great favorite for years.
Rubber tired loaders were around the mills from their early origin, Hough’s especially. As loader technology advanced and they became bigger, they gradually took over from the crawlers. The firm I worked for used all sizes as they became available and were huge buyers of Hough 560’s and 400’s. They never really used the 25K Cat 992’s, preferring the Michigan 475’s instead. That may have been because of the unfortunate incident of the first Cat 773 haul trucks with the fiberglass hoods that burned to the ground on their first loads due to super hot slag spilling off the loader buckets onto the hoods. But in later years, Cat 988’s and 992’s became the preferred machine, with brand new spare machines ready to go and parked at Michigan Tractor in case of need. Haul trucks remained Euclid’s however.