dengel said:
In a previous thread,
Anyone know the MAXIMUM line production rate?, GMlinedog stated that the expected max rate would be 50-60 per shift. So assuming a shift is 8 hours, 8x7=56. So 7 cars per hours would be about right.
But as been mentioned by others, we're comparing apples and oranges. You can't draw a straight comparison between production rate and number of employees. It is possible that the Solstice line will have more work stations or more complex operations, than the L-series line, which would effect the number of employees on the line.
It's not a "straight line" but it IS very correlated. The only piece of information missing is the hours it takes to build a solstice compared to an old L-series. Typical American cars are in the neighboorhood of 25 hours per car.
7 cars per hour and 25 hours per car tells you roughly how many work stations are required to build the car. 7 cars per hour means 8 1/2 minutes of time in each work "station". Simple manufacturing modelling would use these assumptions and work like this:
Every 8 1/2 minute work station is composed of 2 to 6 people (1 to 3 working on each side of a car). Call it 4 for rounding purposes.
25 hours is 1500 minutes - means 176 rough stations (at 8 1/2 minutes each), or about 700 line workers. Multiply by a fudge factor of 2 to account for line management, maintenance, etc. and you get over 1400 people.
Contrast this with a line rate of 65 cars per hour. Maximum time in station is 55 seconds and you can only fit one person on each side of the car per station at that speed. 25 hours is 90,000 seconds - 2 people per 55 second station and you get a smidge over 1600 line workers, or 3200 people when accounting for overhead personnel.
Also, the interesting thing is the max capacity of the plant and line rates seem reasonably close:
L-series intended was 250,000/year at line rates varying between 65-72 cars per hour. 65 cars per hour at 240 standard 2-8hr shift annual operation is 249,600 per year...
7 cars per hour at 240 standard annual work days is only a bit shy of 27,000 per year. Something is wrong with the "60,000 per year" estimate of the Wilmington plant, or they have a second assembly line operating at the same rate that they haven't disclosed yet. It's pretty much impossible to get 60,000 cars from a line rate of 7 per hour...