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Wanabe1972
02-15-2018, 10:02 AM
Any suggestions to rotory vane pump oil? Im currently using Tractor supply Blue for a Delaval 74 dairy pump. It works good with this oil but has always run very hot. Ater just a few minutes of running it has a vapor cloud coming out of the exhuast side. It has the 2 bearing oil lines and a dripper on the infeed of the pump and goes through pint of oil a day on a good run. It has a homemade reclaimer that never catches more than a tablespoon or so a day. Thanks Jeff

Haynes Forest Products
02-15-2018, 10:23 AM
Well I take it you have a DeLaval 74 pump?? You going for HIGH vacuum with no regulator?? So I will start with welcome to the world of trying to make a 1966 VW bug do 120 MPH. If your happy with the way its running and its just an oil reclaiming issue then get a better reclaimer. If its to hot to touch and your afraid its burning up you need more oil, cool oil and I would say lighter weight oil.

Wanabe1972
02-15-2018, 11:57 AM
I do run a regulator and it is regulated to 21 to 22 cause if any higher my releaser doesnt always trip. It is not a performance issue as much as at the end of the season last year it ran super hot. I put a box fan on it and it was better. i was just wondering if a differant oil would keep it cooler.

Haynes Forest Products
02-15-2018, 02:25 PM
The trade off in oils is thicker oil clings better than light weight oils so it stays longer. Thin oil spins off quicker. The quicker oil comes in contact with a hot surface and then flies off carrying the heat away with it is your best scenario. The more oil the better and cool oil is even better. Now that takes a good oil reclaimer, storage for the oil, oil cooler and plumbing to convert your pump to a flood system. Your close but to take the next step you must decide if you can do the work yourself.

nymapleguy607
02-15-2018, 04:12 PM
How many gallons of oil are you putting through the pump? Generally a reclaimed acts as an oil reserve with say 5-10 gallons of oil in it. The large volume of oil insures that the oil has time to cool before it gets recirculated through the pump.

Wanabe1972
02-15-2018, 04:52 PM
The reclaimer never really worked that i built. It would just vaporize the oil and would have just run out of oil. The tank was probably too small because it only held about a gallon. I switched it over to a tank that just has dripper on it and the reclaimer just acts as a muffler. I said at the end of last year i needed to address this and here we go with a new season with no resolution. I will probably just stick with the box fan and extra oil and hope for the best at this point. This is without a question going to be my upgrade for next year.

BreezyHill
02-15-2018, 10:21 PM
Jeff, come on down to our store. I have 5 gallon pails of Vac oil that is good stuff. $59.99. It isn't a super thin oil that will vapor off quick and I can show you how to build a good reclaimer for that pump. I even have a tank you can use to build it from. Got it at an auction for $10. I can get more for scrap price too. you got my cell still..pm if not.

Cooling by oil is a matter of flow into the pump to dissipate the heat. Thinner the oil the lower the vapor point is. You want a 180-190 vapor point. So more into the inlet thru a tee and a dripper. And I got a dripper for ya too. hahaha God I love auctions!

The way I set them up is not less than 12" of copper tubing between the oil supply and the dripper. This length will bring the oil to air temp. You can always go a little longer and do a coil in front of a fan for those hot end of season days. 18"- 24" will be plenty.

Plastic line melts and it doesn't dissipate heat well.

I run a fan for security on those hot days. Black mains get hot on 55 degree days and you usually have less gases on those hot days to keep the pump cool.

Remember the higher the vac the less air the pump is going to have to keep her cool.

Ben

Wanabe1972
02-15-2018, 11:16 PM
Breezy I appreciate the offer but not sure if I can carve it out of my schedule for the next couple of weeks. I plan the tap Sunday and the weather looks good for 7 days or so here. It just came to me that I an running stock drippers to the bearings and a drip into the intake of the pump. Is it possible I'm not flooding the pump enough to make to reclaimer work? What if the pump gets hot to the point that the little amount of oil entering is just vaporizing? I wish the pump was here so I could do some testing. Well tomorrow is another day. Jeff

Haynes Forest Products
02-15-2018, 11:28 PM
There are some quirks about dairy pumps that don't cause problems for high vacuum. Some pumps have oil groves in the side plates that do't cause problems at the lower dairy vacuum levels. Starting a flood oil dairy pump puts a lot of strain on the vanes and shaft under a closed system.

There are different types of oil reclaimers some depend on size to allow the air to slow down cling to baffles and form droplets. Some have course filters to lets the oil mist to condense onto them and settle out. Then there is the coalescing type that use a thick hard fibrous filter that when the oil passes thru nit it sticks to the material and drips down. That style causes more back pressure.

Reclaimers are not used to store large amounts of oil so a tank is the way to go. The oil tank is also the place that allows the moisture to settle out of suspension. The incoming sap and gas is high in humidity and when it hits the pump it warms up and then cools in the storage tank. I found that if the exhaust went into the tank first a lot of the oil would settle down along with the moisture and then exit thru the reclaimer.

I used a junkyard trans cooler between the oil tank and intake of the pump and that would really bring temps down. Having a hydraulic oil filter in the return line before the trans cooler helps keep thing clean.Most newer cars/trucks have so many coolers under the hood you can get them cheap.

I liked to use the thinner trans fluids for my pumps because they would flow thru the filter and cooler quicker and believe they dispersed heat better.

BreezyHill
02-16-2018, 10:42 AM
If the pump is so hot the oil is vaporized on contact then you turn up the oil flow.

End of season my D75 is turned to a stream to keep her cool and I run a fan. The big thing to remember is she must stay below 200 degrees...now your 74 is a different animal than my 75. you likely have Kevlar veins where the odd series of the 70's are the metal veins. A thin layer of oil on the housing from flood or injection oiling will go straight to the housing and give an added seal area and cool the housing.
Bearing oil will initially only get on the end covers and if hot enough it will get no further.

With your machine shop history you likely know that to much oil on a bearing can be worse than to little. Primarily due to the space restraints of good bearings.

Not enough oil for the reclaimer will depend on the design... My preferred design is to have the exhaust entire in the top of the chamber and swirl around the outside of the vessel. This is to contact as much surface area as possible away from the oil reserve. Then the exhausted is directed down thru a heat dispersing medium. Steel wool works very well, in stills they like to use glass beads, bolting cloth can be installed in layers. The theory is the cooler medium will condensate the vapor and drip down to the reserve area. The exit for the exhaust located in the center of the vessel should be located just above the oil level so that any remaining vapor will contact the cooler oil and be removed from the air flow. This style will also do a superb job of muffling the pump noise.

There are numerous ways to increase the efficiency of this design depending on the time one has, the materials available, and how good one is with a mig.

on can even hook up a fan on a sensor to cool the reclaimer if needed.

I prefer the smaller oil reservoir capacity options...if it is 2.5 gallons; the oil will be changed more often than if it is 5 gallons and costs $60 or more to change the oil.

The place to step up the size is the exhaust port of the reclaimer. 2" is my minimum. you want a low pressure flow thru the reclaimer to get the most vapor removed.

Each unit should have a water trap and then a filter for the oil to flow thru. Cleaner the oil the longer the pump will last.
I can do after hours if that fits better for you.

The Sweet Spot
02-16-2018, 01:40 PM
We run a Massport Major rotary vane pump with a gas engine. When we went to pick it up it was completely sank in a pile of manure. The dairy farmer had to pull many times with his tractor and a logging chain before it came out in a frozen block of, yup you guessed it! The block that came with it was twice the size of the pump with the tank. We thawed it out, tore it down, cleaned it up,installed new bearings and composite vanes. I put the manure in the garden. We ran the outlet into a homemade vapor trap. From there the oil goes into a oil filter, through a transmission cooler that is mounted outside the vacuum shed, and from there back to the pump. We have run this pump on cheap hydraulic oil every year and we run over 23" every day. Last year was the first year we had the set up inside. The last day we ran the pump it was getting very warm and when I went to shut it down the plastic parts on the engine had strings of plastic melting from them. Most of this was that the exhaust was not being vented outside. This year we are building a wall around the whole system and adding a ventalation fan with vents to and from outside, along with the exhaust being vented out. I found that with the hydraulic oil I am able to keep the pump cooler with no loss of vacuum at the higher heats. I do have a small fog out of my discharge and will be addressing that with a second reclaimer this year. Dairy pumps were never meant to run like this but they will do it with some care and understanding. Good luck and have fun!

Haynes Forest Products
02-16-2018, 01:43 PM
I remember lending out my vacuum pump the farmer friend and as usual it developed a glitch. He said that the unit was sticking every morning at start up from ice. So he has the local I can do everything farmer mechanic. He looked at my pump set up that I ran for 3 years and changed the oil lines around and shut the intake flood oil line down to about Zero. :o:mad::mad:

Well it turns out that it wasn't ice that was the culprit it was burnt maple syrup. YUP my oil had so much sap mist coming into the pump and condensing it concentrated over time sticking the vanes in the drum. Now I will admit I wasn't doing a very good job maintaining the oil. I figured that because the pump didn't have the usual combustion engine dirt polluting the oil that just adding oil was good enough. When I changed the oil it looked like molasses and smelled like burnt Grade B syrup. having the abilkity to drain the tank of water/sap would be a good thing.

The Sweet Spot
02-16-2018, 01:49 PM
Haynes; I found the same thing last year. My pump would not turn over so we pulled her apart and found what I think was sap sticking things together. Quick cleanup and running again with no problems.

BreezyHill
02-18-2018, 10:01 PM
Sap mist is in nearly every pump at the end of every day. I will get an oz or two every day out of my water trap on each pump. Good vac oil will allow it to separate out very quickly and is best drained on shut off of the pump. If it freezes over night it wont come out.

My routine is to shut everything down and on my way out t night I drain the pumps water trap and refill as needed with oil. If the oil looks off then I drain it right then and refill with new.

In a dairy setup the flood oil is not needed as there is so much free air coming in thru the vacuum relief unit that the pump runs cool. Hot bearings need more oil and the flood oil will increase the seal of each vein.

While it is hard to teach young bucks and old dogs new tricks most will take the info and utilize it down the road.4

Good Luck!