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# Grease Alternative

## Grease Alternative

(OP)
I'm scratching my head (since I'm just a dumb construction worker ;) and figured maybe someone here could come up with a brilliant idea that I'm overlooking.

Background:
We have a large skidding system; essentially it's two heavy steel beams fully reinforced with two inverted channels (picture a cap channel not welded to the beam) on which the item we need to move (typically heavy transformers but whatever our customer wants) sits. Two large hydraulic cylinders pinned to the beam push the channels along the top of the beam, the pins are then removed, cylinders retracted, pins reinserted further along the beam, and then the cylinders re-extended in this fashion over and over to crawl the load forward. It's a fairly common piece of equipment in our line of work. The channels put about 100-140psi onto the beam at full load, but a more common operating range is about 50-70psi given that most of the cargo isn't at the systems maximum weight.

Traditionally we used to use a paste made of ivory soap flakes to lubricate it during use (economically, it was cheap, environmentally, it washed away and the volume we used wasn't a concern at a given site). The problem with flakes was two fold, primarily Ivory stopped selling them in 1993 and other brands just didn't work as well, and secondly, the paste is hard to work with when it's below freezing, which is quite common for our work here in Wisconsin. We were using grease afterwards but as you can imagine, that makes a huge mess since the surfaces are exposed (80' or so, 12" wide, right in the middle of construction sites) so they not only collect all sorts of dust and dirt but also get all over the workers.

We worked with a plastic engineer to design some low friction lubricant impregnated polymer plates to install on the skidding surface to use instead of the soap flakes and grease. In testing they work just fine. The problem we have right now in the short term is the beams have been cleaned and prepped for the plastic install (fastener holes drilled/tapped/etc, repainted), but some emergency jobs came up that we need to use the system on before I can get the rest of the project finished to the point where we can utilize the new plastic wear plates. So in the interim I need some lubrication options better than what we have.

So to summarize all the above:
Is there a good lubricating option for this situation that anyone can think of that is:

### RE: Grease Alternative

Since it's Wisconsin in the winter, how about just water (in the form of ice)?

### RE: Grease Alternative

(OP)
Under those pressures it tends to generate enough heat to just render it back to water. We'd have to put a fairly thick layer of ice to make it work properly and we structurally can't put anything more than a fluid layer in without remanufacturing things (hence the problem I'm having with the plastic).

### RE: Grease Alternative

Not knowing exactly the arrangment, but is it posible to apply a pressurized fed to the slide so no need to coat/lube the lenght of rails?

I have a gut feeling pnematics is not possible, but I was surprised when I first used them to move some shield walls.

### RE: Grease Alternative

(OP)
You mean a pressurized feed of lubricant? Not easily no. These slides travel over the beams until they reach the heavy duty semi-trailer (100+ ton rated). Once they get there, they slide over what we call layover plates, which are little more than 1" plate. bolted to the ends of the beam. So between the load and the semi trailer there's maybe 2" of clearance. To use a pneumatic system would either require more headroom for the pumping assembly, or to drag hoses/pumps/etc around. Right now one guy just goes around applying this stuff ahead of the slides. Another concern is that you're dealing with several hundred tons of steel several feet in the air on cribbing piles. In practice it's really safe, but we still try to keep personnel out of the hazard zone as much as possible, so by doing the rails we can work 20'+ ahead of the load.

### RE: Grease Alternative

Actually, if the rails are reasonably flat, a steady feed of compressed air will do.

Mike Halloran
Pembroke Pines, FL, USA

### RE: Grease Alternative

(OP)
We have air skidding equipment for similar uses on a smaller scale, but no, these are not anywhere near flat enough to do that. The other problem is that the shoes are 20' or so, trying to balance the air over that length when the load isn't always the same size, located in the same spot, or symmetrical makes it difficult. You tend to end up with spots that catch or sag.

### RE: Grease Alternative

When we were stretch forming aircraft stringers we had a similar requirement for a grease that would wash off.
We used a substance called Duckbutter made by Oatey. This was basically a soap with other ingredients added, we would buy this in 5 gallon pails.
This would stand the extreme pressure of the stretch forming machine allowing the parts to slide over the die,
and it washed off with water. Try contacting them and see if they have anything that would work for you,
B.E.

You are judged not by what you know, but by what you can do.

### RE: Grease Alternative

Lard is an excellent metal lubricant with soap and water clean-up ability.

### RE: Grease Alternative

(OP)
Berkshire & Compositepro: Both are good options. Thanks!

### RE: Grease Alternative

(OP)
Berkshire: I called Oatey, Duck Butter starts to harden around 10F, we're working outside on one of these right now and it's -3F so Oatey recommended against that product. Their guy is digging around to see if they have anything else that can handle the cold but he didn't sound promising. Might be a good option if it warms up though.

### RE: Grease Alternative

WRT air levitation, this may come in handy in the future.

Instead of feeding air into the center of one huge rectangular flat bearing plate, divide the plate into sections, e.g. by routing a groove around each section, leaving a margin between the groove and the edge of the material, and feed the air into the center of each of those 'pads'. If the air feed to each pad includes an orifice, the pads will self-adjust to some extent. You might include a ball valve to shut off the air to some pads for grossly unbalanced loads, but the orifices should make that unnecessary.

The edge margin and the central portion of each pad can be at the same level; no need to get fancy. The groove equalizes the pressure around its periphery, and once levitated, the central pad will be at the same pressure. The leakage rate can be estimated by assuming a levitation distance, with only the edge margin subject to a pressure gradient, and the central pad and the groove at a uniform pressure. In oil hydrostatic cylindrical bearings, the orifices are sized so that the pad and groove are at half the supply pressure. In a flat bearing, you have less control over the gap; it is what it is when the pad pressure times the pad area balances the load.

Mike Halloran
Pembroke Pines, FL, USA

### RE: Grease Alternative

(OP)
All I can really say about air skid systems is that I'm not impressed. We have one and it's been hardly used at all. They require far too ideal of a situation to work properly in our particular application. In regards to floor skids, for the weights we deal in they require some pretty smooth floors which are awfully rare, plus they have to be clean, small metal chips would cause them to lose too much air and stop working, and there's the noise of having to run high CFMs of air to support it. In the particular application I'm referencing above, the beams aren't always perfectly level or square to one another so you'd have a whole ton of jointed segments, and more joints means more parts which means more points of failure. It's just not as simple as the current beam/shoe/ram setup.

I think air skidding systems have their place, we've installed air bearings and similar that work really slick, but my experience is that machinery moving is not that place.

### RE: Grease Alternative

The duck butter was simply a commercial substitute for your soap flakes which you now cannot get.
B.E.

You are judged not by what you know, but by what you can do.

### RE: Grease Alternative

Maybe get a local Amudh enclave to cook up some soap for you.

### RE: Grease Alternative

Seems like in your business you would have tried electrician's cable pulling soap, good to -20F -

http://www.polywater.com/polyj.html

Also, a word of caution on your polymer skids - steel beams can expand/contract at about 1:10 ratio to the plastics. Make sure your plastic skids are designed for differential thermal movement of the steel, or you'll end up breaking the holes out on the skids.

### RE: Grease Alternative

(OP)
There's a good 1/4" of play between the steel and polymer on the edging, and the bolt restraints were engineered by the plastic company with tapered head bolts installed in a manner that gives them some slop to allow growth parallel to the fasteners axis so that shouldn't be an issue.

### RE: Grease Alternative

You could look at Xanthan gum,
Xanthan Gum is specially produced as mud additive for oil drilling and exploitation.
It is also used as thickener/ food additive.
It is available as a brown powder which when mixed with a surprisingly small amount of water, produces a compound that is slipperier than snail snot.
It is very similar in feel to the cable pulling compounds mentioned earlier. When exposed to the weather it is subject to bacterial attack, so hose it off quickly after use.
B.E.

You are judged not by what you know, but by what you can do.

### RE: Grease Alternative

Can you spray vegetable oil ( PAM ) on the surfaces?
Would a laundry detergent work?
You could go to a nearby McDonalds and ask to mine their throw away deep-fry oil that is often turned into BioDiesel

### RE: Grease Alternative

One thing that also might help reduce friction between the rails and channels is using the hydraulic cylinders to pull the load rather than push the load. With the type of sliding contact present between the rails and channels, a "recess" sliding condition produced by pulling the load will create far less friction than an "approach" sliding condition produced by pushing the load.

### RE: Grease Alternative

I think we have found another application for Whale blubber.
Sorry, first day back to work in the new year....with the flu.

### RE: Grease Alternative

Just saw my last post w/ typo. Meant to say "Amish enclave". Plenty of them in Wisconsin. Most are quite happy to do business with "Englisch".

### RE: Grease Alternative

(OP)
tbuelna: Pulling isn't an option 95% of the time because of the way it's configured. We can't pull over the layover plates since they don't have the beam underneath them so there's nothing to react against, and the shoes are expandable with bolt on sections so they don't have eyes at both ends, if we want to switch from pull/push in the middle of a move you have to jack the entire load up, spin the shoes, relocate the cylinders and locking shoe, and set the load back down. When you're dealing with 200-500 ton that's a bigger task than it sounds like.

### RE: Grease Alternative

KY Gel works great for some applications, usually she’s warmer than 10̊F though. And now, Trojan and others actually have products which will make the main rail beams or the skid channels smile and coo, so they say, depending on which member they are applied to. I would make the ‘Duckbutter’ or the cable pulling soap work in cold weather by playing rose bud heating torches on the webs and undersides of the flanges of the main rail beams to warm them a little above 10̊F. I’ll bet that the lubricity doesn’t really disappear completely at 10̊F, the product just becomes much less fluid, and you might still have the cylinder pushing cap’y to slid the channels. Immediately behind the pushing cylinders I would use a long handled ice scraper to remove most of the lub from top flange of the main rail beams. I think I do understand the benefit of pushing cylinders as apposed to pulling cylinders; full fore of the cylinder pushing and pushing the load onto the trailer.

I’m in St. Paul, MN, so I do understand your cold weather problems. Are you in the Milw. area? The plastic bearing pads depend on running on smooth, clean rail surfaces and can be seriously abraded at any top flange roughness or joints in the rail beams. So, as a min. align the top flanges of the rail beams well, and grind a radius on the sharp edges which might contact the plastic pads. I’ve always run plastic bearings on plated, polished surfaces, not rough steel. Although, they can be replaced for a reasonable price as they abrade. It seems to me that the best design might be four plastic bearings (shoes) 18-24" long fixed to a 1" steel bearing plate assembly. Then, these bearing assemblies get located on the skidding channels as a function of the load application points on the loads which you are trying to move. And, the underside of the web of the skid channel is actually 1.75" above the top of the main rail flange.

### RE: Grease Alternative

(OP)
The beams have cheek plates so heating the bottom of the flange isn't practical plus when you're dealing with hundreds of feet of beam that's a lot of labor which is why I'm keen on switching to something free flowing at below zero.

We are in the Milwaukee area. Oldest machinery moving firm in the state to the best of our knowledge. :)

As for the bearing pads, they specifically chose a polymer that is really durable on non-machined runners. It's actually primarily used as the bearing plates in mining shovels where they routinely turn into 'dirt mills' from all the stuff getting between them and the steel of the upper cab. The plastic is lining the beams not the shoes so we had them chamfer the leading edge on every skid plate and we're putting a leading chamfer on the steel shoe so they should ride nice with no sharp edges to cause any planing. We made them in 4' sections so that if one gets damaged/cracks/whatever we can replace it without having to redo the entire beam. All the bolts are flat head countersunk so they are well below the top of the skidplate to allow plenty of wear.

### RE: Grease Alternative

If you can't use the hydraulic cylinders to pull the load instead of pushing it, you might be able to produce a similar effect by adjusting the relative vertical locations of the hydraulic cylinder attachments. The difference in sliding friction produced at the rail/channel contacts can be quite substantial with recess vs approach contact conditions.

If the force vector of the pushing hydraulic cylinder is offset well above the forward contact point of the rail, then the pushing force will promote an approach type contact at the leading edge of the skid and greater friction. If the force vector of the pushing hydraulic cylinder was tilted so that it was offset below the forward contact point of the rail, then the cylinder pushing force would produce a moment that promotes more of a recess type contact at the leading edge of the skid and lesser friction.

Sorry if these suggestions are not practical for your current situation. But they are definitely something to consider with future moves.

Regards,
Terry

### RE: Grease Alternative

Molybdenum disulfide is a fantastic - one of the best - dry lubricants. Soybean and sunflower oils melt within a degree of each other at around 0 deg F. Blend powdered MoS2 with one of the above oils, and that should be slicker than pig snot. Biodegradable and pretty cheap, too. Pick your blending oil depending on expected temperatures.

References:
http://en.wikipedia.org/wiki/Molybdenum_disulfide#...
http://www.engineeringtoolbox.com/oil-melting-poin...

Alternatively, you could try talc blended with an oil that's semi-solid at the expected temps. It's almost as good a lubricant as MoS2, and much cheaper (think baby powder).

I grew up in Cedarburg (just north of Milwaukee, for those not from WI) so I know the cold you speak of :) It feels like your face will fall off some winter days.

SceneryDriver

### RE: Grease Alternative

(OP)
TBuelna, I'm trying to understand what you're saying and coming up empty. ;) Currently the cylinders are set to the eyes are approximately the same height, meaning the cylinders are parallel to the direction of travel (more or less). Are you saying that it should be tilted so it's higher at the load side or higher at the dead-end side?

### RE: Grease Alternative

(OP)
Scenery: I'll look into the molybdenum. And yea, it was -14F here on the way to work today. Fun fun.

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