I recently participated in a meeting attended by Representatives of a large coal mining company, the Federal Mine Safety and Health Administration and the Bureau of Mines, State of Pennsylvania. The meeting was called by the mining company in order to determine what would be required to change laws requiring the use of heavy-duty double jacketed portable electrical cable (commonly termed "Drill Cord).The intent of the mine was to be allowed to use "SO" type cable. This intent was directed partially by cost, but the primary reason was the difficulty in securing a dependable supply of the required "Drill Cord".
It has been my experience, that the difficulty in obtaining this particular cable is very real. The reason given by cable manufacturers for this is the limited demand for this particular cable, whereby this cable has a limited production run.
The mining company involved in this meeting, estimated a cost of three million dollars for the amount of cable they would use.
My questions are: What constitutes "limited demand" in the cable industry and is this why manufacturing is going away here in the U.S.?