Modernizing an in-floor lift?

[50pascals]

Hi all,

I recently purchased a shop in town that has an air over hydraulic, low pressure, Globe in-floor lift. I can't post pics or links, but do a google search for "Globe Frame Kontact" lift and you will find some green and orange vintage ads of my lift.

It works great so far. I am told it had a small leak that was fixed in the 80's. And I can see the concrete was repaired all the way from the valve assembly to the hoist. I do not have a pipe fitting protruding anywhere, but there is a round concrete patch that I suspect covers the tank.

In order to avert a potential environmental disaster, I am planning to replace the hydraulic oil with a plant based hydraulic oil. Because plant based oil tends to oxidize or otherwise degrade more quickly than petroleum oils. So I would like to convert the lift to use a sealed tank and a low pressure hydraulic pump. I believe I could use a pressure tank for a well, or another air tank that would allow me to keep the system closed, and also keep the pressure well under safe limits for the tank.

The lift also has no safeties other than a homemade kickstand. It does not creep down at all, but safety is always an important consideration. So I am wondering if anyone makes a mechanical safety to retrofit to these style hoists?

I've tried doing some searches for both of the above ideas with no luck. I'm not worried about designing my own system as I work with industrial hydraulics all the time. But I was looking to see if anyone sold a kit, or to learn from any mistakes others made before me when converting to electric.

Thanks,

 

[oilslick]

I have experience with single posts. If it utilizes an underground tank I would abandon it. If it is self contained with fluid inside of the cylinder, keep it! I added my own safety post on mine using schedule 80 galvanized pipe with numerous holes and a heavy duty hitch pin to install when it was at desired height. Looking back, much wasted time and effort. Everything you do will rely on there being no weak link in your hydraulic system. As old as it is, figure something is rusted underground to nearing failure. It could be any part of the cylinder or a simple elbow fitting at the bottom but either way I never fully trusted mine so it was of little use to me besides a nice work table and loading dock!

 

[matt_i]

Imo your easiest path to get what you want, is to cut the floor, tear it out and metal scrap it, re fill.re-pour the floor and put in a 2 post lift.

The low pressure means to me that big cylinder areas are used and hence giant volumes.

Your pump (power unit) is going to have to replicate that (large flow + low pressure) which is atypical from most of the hydraulic power units I see used in manufacturing.....those are "high" pressure in the 2000-3000 psi range and flow to match the application.

Its not to say that you couldn't get a 10 or 15hp unit to get the required flow and set the relief way down, but that becomes an expensive electrical proposition without 3 phase power. If you have to custom-spec any kind of single-phase hydraulic power unit it is quite likely to exceed the cost of a 2 post lift....

 

[rockettgpw]

Have a look at the thread on here called "Restored 1930's Auto Shop" in there Thomas did a story of keeping an old Rotary inground alive. The lift story is closer to the start of the thread. It's an epic thread with over 12k posts.

 

[finn]

We had an in ground lift near the dynamometer cells at work, probably installed in the mid eighties. Ten or fifteen years later we couldn’t get parts so they (facilities) tore it out, only to discover contaminated soil, which had to be trucked out to a hazardous waste disposal sight.

It wasn’t pretty.