I worked in a packing plant off and on for several years while I was going to school. The animals come in up a ramp into an area where they can be penned one by one. Cattle are killed by a
pneumatic gun that punches a pin into their foreheads (this replaces shooting them), sheep are killed by stunning them with a pneumatic hammer. Animals are then hung upside-down on trolley hooks and
bled out over a catch basin which leads to a below floor tank. The trolley rail then curls about through the killing floor past workers who "disassemble" the carcass until there are only two halves
hanging by their heels and everything else has been carted off. All the "useless" parts are thrown into a huge pressure cooker called "the tank" which cooks and grinds everything. This material is
then squeezed in a large press to remove the tallow and the remaining dry powder is put into sacks. This "bone meal" is used in fish food and fertilizer. The tallow (which smells awful) is shipped
off in tank cars. .
The hides were removed very early on in the disassembly and carted to an outbuilding where they are salted down until enough have been collected to make an economical shipment To ship them you first
have to pull them out of the pile and shake out the rock salt. They are heavy, wet and smelly and this is one of the disgusting jobs that I often drew. There are a number of very large coolers since
beef has to be aged before it is shipped. Many plants have a butcher floor so that they can supply various cuts of meat to their customers as well as halves or quarters. Most plants also make
prepared products such as lunch meat, bacons, hot dogs, hams, etc. These require several large smoke houses and a fairly mechanized line where the, for example, salami is sliced, packaged, crated and
paletted for shipment.
All of the products mentioned so far can ship by either rail or (more likely now) trucks. This requires a fair size loading facility which is fed by trolley rails from the coolers. Prepared products
are moved by forklift or pallet jack from the coolers to the truck or train.
Carcass halves and quarters arrive on the shipping dock still hanging from the trolley hooks and are carried (yeah manually) into the truck or reefer and re-hung on hooks. This is another intensely
laborious job I did very frequently (this all happened when I was young, quite strong and not as "bright" as I am now). There also needs to be storage for the various supplies such as rock salt,
spices for the prepared products, pallets, shipping cartons (and a place to "unflatten" and staple them just before use) butcher paper, locker rooms and lunch rooms for the employees and a million
other small items.
I suspect no two plants are laid out exactly the same but typically many of the supplies such as bales of corrugated cartons would be stored in some sort of "attic" area" and the "tank house" and
other areas to deal with by-products would be in a basement type area. The plant I worked in was remodeled and had major rearrangements twice during the approx. 4 years I worked there in attempts to
improve the efficiency of the entire operation and meet changing market demands. Of course, you also need some pens and facilities to keep and feed the animals until they are ready to butcher.
The above applies to cattle butchering which is what I mostly was involved with. We also did sheep on occasion. The sheep had their own "disassembly" line as the process was somewhat different
physically. Cattle hides peel off easily once correctly started but sheep skins have to be very carefully cut from the carcass inch by inch. Sheep are also much smaller than cattle but come apart
with more difficulty so there was a separate line just used to kill sheep. We also had a line to do hogs but I never saw it used as it was so incredibly labor intensive and messy that the company had
given up on butchering hogs. The hog line had a long, complex, conveyer system of carts moving on rails, tanks of scalding water and rotating brushes that were used to get the bristles off of the hog
carcasses. Hogs are not skinned. This line took up as much room as the sheep line and then fed into the middle of the sheep line.
This all was +/- 40 years ago and I suspect some of the details are outdated but the overall process can't have changed all that much as the animals are still pretty much the same models we worked
with.
Walt
Actually, almost all precooked meat products were mixed up in a grinder that looked exactly like a giant size version of the one your mom clamped onto the counter and used to make sausage except
it had an electric motor instead of a crank. The product was extruded into the appropriate size casing (small for hot dogs, etc.; large for salami, bologna, etc.) and then sent through another
"thingie" that tied the casing at appropriate lengths (5" or so for hot dogs, 36" or so for almost all lunch meat). Hot dogs everyone has seen, large sticks of bologna, salami, etc. can be seen in
any real deli, they are invariably cut in half before shipping to the deli or butcher. Then the product was "cooked" in the smokehouse rather than a pressure cooker or oven. The smokehouse burned
apple sawdust. Since buying a cabin in "apple country" (eastern Washington) I've learned that apple sawdust comes from grinding the limbs that are pruned off each spring - and there is a LOT of wood
pruned off of the average fruit tree.
The vats (actually tubs that had feet that looked kind of like boxcar stirrup steps) that we soaked pork bellies in to cure them into bacon were stainless steel and about 4' wide by 5' high by 8'
long and were really heavy, even when empty. I severely threw out my back once just tipping an empty one up on end. Strings of hot dogs, bologna, salami, etc. were "extruded" into about half size
versions of the same thing. Don't forget that almost everything that the meat touches is made out of stainless steel so it can be cleaned with a very hot.