OK, I did exactly what you are trying to do and more. I wanted NO overhead wires, conduits, pipes etc. I wanted my lift to have a clear floor and not have a cable tray on the floor for the lift cables between the columns. To solve the cable tray issue I went with a Mohawk hydraulic synchronized system. It does not have cables from side to side, only SS hydraulic lines.
I planned the lift installation before the floor was poured. I was unable to find the pics showing the conduit run before the gravel base was put on top of it. Basically I dug a 6" deep trench in the ground and ran the PVC conduit from the breaker box to the lift area and then just used a normal sweep 90 and left it about 5' straight up in the air. I used a 1" conduit so I would have plenty of room. Then the conduit was covered with dirt, then the gravel was installed, I can't remember how many inches of gravel though. Then a 6" concrete slab. You will also notice that I put rebar in the concrete under the lift location. The lift mfg didn't require it but it was cheap and now was the time to do it. The lift location has a depression in the gravel, so that the rebar will be 6" down from the top of the concrete. I think the total slab thickness at the lift is 10". This allowed for the rebar to be there but when I drilled the holes to mount the lift the holes being 4-5"" deep would never worry about drilling and hitting rebar.
You can see that there is a piece of rebar stuck in the ground, this is to support the conduit. I also installed a 1/2" conduit from the right side to the left side for an electrical outlet on the opposite side. Also I bent and installed, alongside the 1/2" conduit, a set of SS hydraulic lines. These lines can be bought in 20' lengths so there is no splice under the concrete. Finally there is a second 1" PVC conduit on the left side installed just like the right side but I used gradual sweeps here. This conduit just goes to the back wall. I later installed an air line into the conduit and a hose reel to the column on that side.
The second pic shows the lift mostly installed. I have now finished building a guard box around the conduit where it exits the concrete. Now it won't get damaged by tripping over it, car doors etc. As suggested by others you could use a rigid steel conduit where it exits the concrete for extra protection, however since I was protecting it with a cage anyhow, it was well protected. Notice though that I did transition to EMT after exiting the slab. Another tip, leave the conduit sticking up quite far before you pour. If it's sticking up 5-6' in the air it's harder to trip over when it's in the line of site, hang a bright rag on it also helps.
If I get a chance I'll post the pics of the finished install with the guards.
Brian
