Episode Transcript
[00:00:00] Speaker A: Good day, everyone.
[00:00:00] Speaker B: Welcome to lubrication explained. All right, so another session with Danilla from Graco, our friendly Uber driver. So this time, we're going to talk a little bit about pumps, pumping fluids, all that kind of stuff.
Most people, I think they see these kind of pumps. You can see another example behind you over there. Most people look at these pumps and just, I don't know, it never really occurs to you how they work on the inside. So it's kind of helpful that while we're here at Graco, they've got a cutaway version of one of these pumps, which obviously are really prevalent throughout the industry. I thought it might be worth discussing, just first of all, how these work, and then we'll talk a little bit about specialty pumping situations. So, for example, when you've got grease, greases at low temperatures, some lubricants at low temperatures as well, because one of the things that Graco, I think, does quite well is move fluids, right? So they obviously do paints, they do adhesives, they do glues, they do all kinds of other stuff. And so, you know, having a look on and doing a little bit of troubleshooting, I think, with Danilla about some of the issues that he encounters or common issues that he encounters with some of his clients might be kind of helpful. All right, so, Danila, do you want to just take us through the generic operation of this? One of these?
[00:01:17] Speaker A: Yeah, the generic. I mean, most typical pumps in the industry, in any industry, but especially if, again, we're talking about the lubricants industry is going, the pneumatic pump, this is the most common source of air power. And most of people use pneumatic pumps because they're relatively reliable, I would say. And they have less active parts, like in electric pumps, where you have the electric motor, the gearbox and all the connections, all this electrical stuff, some people don't find it reliable, and they prefer pneumatic pumps because the air is moving the fluid. So, in a nutshell, how does it work? So this is the typical. As the legacy, I would say. This is the fireball looking pump. So we have here the fireball pump behind me. This is our, I would say, probably if you go to any mine, anywhere in the world and you go to the workshop, most likely you will see a fireball pump. So customers may know us by the fireball name. So this is nice looking, nice sounding name. So this is the air motor here, which is from the fireball family pump. So how the pneumatic pump works, I mean, in a nutshell, really. All we have to do. So there is an air inlet, there is a fluid outlet. So and these pumps, they have got different pump ratios. So what is the pump ratio actually? So there can be one to one pump, three to one pumps, five to one pumps, ten to one pumps, 50 to one pump, 36 to one pumps. So this is actually the ratio between the effective area of the air motor. And the effective area of the lower part of the pump. So, meaning, let's say if this would be, for example, ten to one pump. Then meaning the effective area of the air motor here. And the lower part is here. So this part would be ten times low. Like ten times less than the effective air motor area. So why it is designed that way? Because we need actually to create pressure in the line. So and all of these pumps for different fluids, for different applications. So also it's very important to know that if you, for example, take one family of the pumps. And you will say. Because we also in Greco, we do have like fireballs. Five to one, three to one. Six to 110 to one. For example, for example, the series of three to one, six to one and ten to one. They share the same size of air motor with 4.25 cubic inches.
It's fireball for 25. So there. And they all have options of three to one, six to one and ten to one. Meaning that if they have the same air motor. What is different is the lower part is different of the pump. So the three to one has got a bigger lower part. Six to one smaller. And ten to one even smaller. So even though ten to one can create higher pressure. Meaning it can create. It can overcome a higher pressure drop in a line. If you have a cold temperature, a thick lubricant or just a long dispensed line in a workshop. So you most likely go for the ten to one pump. But it's not that black and white, I would tell. So. And the point here you need to also you need to remember that, you know, if someone wants the higher flow, they go, hey, I need probably higher pressure. I need ten to one pump. But in fact, no, because if you're going, for example there from three to one to ten to one pump. You're reducing the lower part. And the lower part is actually responsible for the flow. Because we count how much oil we can move during the one cycle of the air motor. So the air motor air comes inside. So air motor creates. The air creates pressure. In the downsides right now of the air motor. The air motor piston goes up. And while moving up, it actually also moving the rod over here. So if it would be an oil pump, it would be just a suction movement. So it would suck everything beneath it. So that's why most likely you will see just, we call the universal pump. It's basically the air motor. It's a short part here where you connect your hose, a tube, or whatever else you want to connect to put it on drum, on a tote, on an IBC, on a bulk tank, or anywhere else you can put it. So when the air motorhouse moves up, it also sucks every oil, which is downwards from the pump. And then as soon as it reaches the valve, the air valve there would switch the sides and then it would start. The air will start flowing backwards. So it creates movement backwards. So basically, the air just circulating inside of the air motor up and down, up and down. And when they're doing the cycle, you may hear this sound. So this is the exhaust. Because we can also, we also need to release the pressure in the lower side of the pump. So while moving, the air piston moves up and down, we also see that it creates a suction movement. If it's oil, if it's a grease, it's a bit different, because with the grease, we cannot just easily suck the grease because it's not like fluid, it's very hard to move it. So for the grease, we actually use so called shovel tube on the very bottom of the pump. So it actually just also the whole, this is all connected through a rod would be connected to the air motor, and then it would just also create like a piston movement up and down. But also with this mode, it actually, like, with the shovel tube at the end, it actually takes a little bit of grease and pushes in the line. Pushes in the line. This is how it actually works. So coming back to the three to one, 6110 to one. So three to one pump, you know, have much higher form than ten to one, but it has much less fluid pressure because also it's very easy method. So typical maximum air pressure on the inlet of the, of the pump is like maybe seven bars. But the typical operating that everybody is using is like five bars air pressure inlet. So what does three to one tells us? So if we give five bars air pressure inlet on a pump and it's a three to one pump, then it will be three multiplied by five, meaning I can create only 15 bars the working pressure with this fluid. If it's a ten to one with the same five bars air pressure, I can already create 50 bars. So it can also, and we need the higher pressure when we need to move some thicker material or we need to move to the further distances, or if it's a colder or any other particular reason. So that's why there are different, different types of pumps in that regards. For example, the big example I have, for example, for the open gears lubrication. So we have the pump, which is a typical grease pump, is the 51 pump. So this is the most typical pump. If anyone asks, hey, do you have a grease pump? They will most likely give you 50 to one pump. So if we also give five bars air inlet, it will give you 250.
[00:08:01] Speaker B: Bars outlet, which is really good pressure. But also with that reduction, you can almost think of it like a gear reduction. That's why grease is so slow to pump too, right?
[00:08:10] Speaker A: Exactly so. But also for the open gear applications when it's a colder environment, we have got 75 to one pumps of. And the point here, it's the 75 to one pump has got the same maximum fluid pressure as the 50 to one pump.
350 bars, for example. So it has got the same maximum working pressure, although the pump ratio is different. So the point here is if you have got the limit in your air availability in your plant, probably, and you have only like four bars, with 50 to one pump, you can create only 200 bars. But you probably want to go up to 300 bars because you need that pressure to move the fluid because it's cold in your salmon plant or something else. So the easiest solution here is going for our 75 to one pounds. Because with the same amount of air, we can create higher pressure, the flow will be lower. But we don't always need flow.
Sometimes, especially with grease, we need some pressure in the system, especially open gear lubrication, because we don't need much lubricant there, just need spray a little bit. And we need to make sure that the grease is delivered to the spray guns. So that's the pump ratios, the differences.
But also talking about the grease, there is a big problem moving greases. I mean, especially in the environments where we have a big, large automatic lubrication reserves, like let's say a mining shovel or something, where you have 180 kilos drum of reservoir there, like on the big shovel or some custom made for 400 kilos there. So if you take a typical 50 to one pump, it would give you most like two, three kilos a minute on the free flow. The free flow meaning if just we stick the pump on the grease, we don't connect anything on the outlet and we just let it run. It will probably give you two to three kilos a minute.
[00:09:59] Speaker B: Yeah. So with the additional back pressure of all the lines, then you're expecting much slower than that.
[00:10:05] Speaker A: Like one and a half, maybe 1.5 kilos a minute. So you can imagine 180 kilos, 1.5 kilos a minute. I mean, it will take you, like, a couple of hours to do the refill. And it's true story. I mean, if you really speak to someone, you know, hey, how much time does it take for you to refill auto loop on this big shower? They most likely tell you that's the pain for them. So on all these loop trucks that they have, you know, they have these typical 52 one pumps that just. They're doing great job for greasing these yerx for manual lubrication, but for transferring grease, it's not the ideal pump. So, like, I. Graco, yeah, we do a lot of stuff. Moving fluids, different kind of fluids. We share air motors between different divisions to share the technologies between vcvs and the Graco, so. And we have really nice pump, which is like, has got 36 to one pump ratio, so. And it has got 7.5. So this one is three inch air motor, and this is a three inch air motor behind me there. But also we have got 7.5 each inch air motor. So we took that air motor, we put a big lower to that pump, and we created 36 to one pump, which can give me the pressure of 3600 psi, which is around 250 bars, I guess around that, which is pretty decent pressure, especially when you need it just to move. You don't need to grease on the high pressure, but it also gives you a flow of 14.5 kilos per minute. So it's insanely higher, like seven times higher, so, meaning it can easily transfer a drum of grease. And note Gi two within 15 minutes easily. So the pump, I mean, really, if you want to be. Smoke a little bit, if you want to move higher amount of fluid, yeah, you need a bigger pump, but you need a smart, bigger pump. So you need to make sure that you have your right pump ratio to create enough pressure in the line. But also you can go for a bigger pump. Or one thing I also noticed in the field, and again, in the cold environments, in loop truck applications, where they say, I speak to the customers and they say, hey, I mean, I have this engine oil. We just changed from this brand to another brand, are really hard to pump in the winter, or it's gear oil, even more harder to pump because it has higher viscosity. And he said, we want to change the pump. Can you offer us a pump or something like that? So, you know, I would always, I could offer them a pump with the higher pump pressure, but with moving to the higher pump pressure, they are losing on the flow because they can create like ten to one pump. For example, our fireball, I think on a free flow is around maybe 30, 40 liters per minute. I don't remember exactly. And our three to one pumps can give you over 100 liters a minute on a free flow. So pretty high flow. So. But there, the solution is different because pump is part of the problem, potentially, and the oil is never a problem for that. I can tell you even I would never actually say that, you know, the pumpability of oil. And if we are talking about this fresh oil dispense, I would say I disagree that the oil can be a problem there. It's the system that can be a problem there. Because first of all, you need to have a right pump which can create enough flow and enough pressure which you want to achieve. Then you need to make sure you don't downsize your tubing and your piping. You don't use narrow pipes and narrow tubes. But the most important in these loop trucks, in the big workshops, they use hose drills and those like 15 meters hose in a coil and very locally. And then you have got a meter handle. You take this 15 meters and it's outside if it's cold. So it's getting cold. Pretty much cold. So, you know, from the price standpoint, half inch hose reels are more affordable. I would put this way. Then they have got only half inch hose reel inside 15 meters. There are more robust outdoor rated hose reels which can be mounted outside. Train snow, doesn't matter anything for them. Quite robust hose reels. And they have three quarter hose reel. And I can tell you changing half inch hose reel to a three quarter hose reel have a higher impact than changing the pump. Because we've done, we have a graco.com website. If you go and search like pressure loss calculator, we have really nice tool, the pressure loss calculator, where you can actually type your system requirements. You tell you like you got 15 w 40, you got your ambient temperature, you tell what is your desired flow, because also all times you see, you know, the meters, the handles like 68 liters per minute or 70 liters per minute, the flow rate. And they say, hey, I want this one. You know, I want the higher flow meter. But this is just the capacity that it allow 68 liters to be flowing through it. But you need to make sure you have the right pump at the system that can actually create this flow. Because if you use like three quarter, like 68 liters per minute meter, but you are using half inch hose drill and you're using like ten to one pump, I mean, you can get like ten liters per minute maximum. You don't need that meter anymore just because you squeezed your system. You squeezed your system, you squeezed the pump. The pump is not performing, and it's supposed to perform in this application. So, so in this calculator, the pressure loss, we take into account the fluid, the temperature, the flow, desired flow rate. What do you want to achieve the flow rate? How much do you want? You also put the hose wheel there, the distance, the height, you know, the size of the piping to the hose reel and everything. Everything gives you a, the pressure drop in your system and also suggest your graco pump for the system to achieve the desired volume. So I can tell you on the same specs, you can use a half inch hose drill and then you change it to three, four hose drill, the pressure drop will be four times less just replacing the hose drill. So with those customers that I have discussions, all I tell them, hey, man, you just, what kind of hose rule you have? Like a half inch? And I think, well, you don't need to change the pump. You can leave the pump. You have just change the hose drill. It's much less. I would say cost would be for you just changing the hose because you just squeezed your system. So the pump is not always a solution, although you need to have a right pump. So it's really. So that's why what I'm trying to do, like, especially working with the money, is that really, like, what do you want from the system? Like, we have got big range of different pumps for different applications for different reasons. And not always you need to go for the bigger pumps you have. For the most expensive pumps you have, you need to come smart. You really need to see even the biggest, the most expensive pump may not work in your system if you are just simply using the wrong piping size.
[00:16:44] Speaker B: Yeah. And I mean, so there's a couple of things in there. Right. Part of it is certainly line sizing. Right. And obviously the back pressure is kind of a function of both the circumference. Right. Of the, of the tubing as well as the area. Right. So the area kind of governs your, your flow rate that can go. Obviously the circumference is going to determine the interaction of the fluid with the wall. And so when you put all of those two together, then yes, small differences in pipe diameter can make a very big difference in when it comes to back pressure and therefore flow rate. So that's obviously something to keep in mind.
One other thing, you know, is obviously going to be temperature, because this is not something that I typically encounter with a lot of my customers, because being in Australia, we don't get the low temperature extremes that we do in Europe, right? So if you're somewhere in Russia or, you know, northern Finland or northern Sweden. Sweden, you know, if anyone's seen the charts, for example, you know, even just oil, let's not talk about grease just yet. Even if you look at oil, right, and you look at the chart of, let's say, base oil, viscosity versus temperature, one thing that you'll see is that it looks relatively stable. Let's say between 41 hundred. We measure viscosity index between 41 hundred. But when you go the other way and you start to go from, let's say, below zero to, let's say, minus ten -20 -30 what you see is a very sharp inflection. And even on a logarithmic graph where, you know, you expect to see straight lines, you're even, even then seeing it substantially increase at low temperatures, which means. And that's where the advantages of synthetics comes in, right? Because the differences in viscosity between a mineral and a yemenite synthetic, and not. Not that much, you know, at your mid range temperatures of 60 or 70 degrees celsius. But when you get to -30 -35 when you're kind of approaching the pour point, then it's a. It's a dramatic, dramatic difference. So, yeah, definitely. Like, obviously, line sizing has to go along with pump sizing. You've got to kind of look at the entire system as a unit.
[00:18:58] Speaker A: It'll be the side track that you'd have you touched. A nice topic about the cold temperature, cold temperature, pumpability of the oils. But I wanted just a quick example of greases as well. So the grease is not Newton liquid. It's very hard, really, to measure its viscosity to understand.
But what is interesting, so we've done some cold temperature tests for our electric pumps, for automatic lubrication systems. And what is interesting, you know, most of the people go for the lowest LGI, thinking that this is the solution for their problem, for the pump ability, but sometimes not the case because, for example, we've done tests. So we've taken, for example, a mineral based grease with an LGI zero hundred centistokes base oil viscosity, lithium complex, 5% molybdenum inside.
And we measured the flow rate of our electric pump and the highest pressure, and this -40 degrees. See it? At the 3500 psi, the flow rate was roughly zero point, I think 86 cubic inches per minute. And then the same pump, the same conditions, the same -40 degrees c, the same pressure, 3500 psi. But we took one and a half LGI, fully synthetic lithium complex grease. Also 100 centistokes base oil.
And actually the flow rate was nearly two times higher than with an LGI zero degrees. So it's nlgi zero, nlgi one and a half grease. So NlGI, one and a half is being pumped, has a higher flow with the same pump because just basically have synthetic in the base.
[00:20:37] Speaker B: Yeah, that's, that's an interesting one. Right. So certainly. Okay, so let's go. General rule of thumb versus specific, right. So I don't exactly know what's going on there, but. But as a general rule of thumb, when you're operating at the temperatures that you see in like australian mine sites, most of the time, yes, you go with a lower NLGI is more pumpable. And that's why, you know, these semi fluid greases are very typical of centralized lubrication systems. Your NLGI, zero, double zero, triple zero. You know, that's, that's very typical because obviously the, the less thickener you have, then theoretically the more pumpable it is. Now, what's interesting is that when you get to extremely low temperatures, and I'd have to talk to a grease specialist about this, but I would assume that the base oil viscosity starts to kind of dominate the flow properties. So we just talked, for example, about the fact that at very low temperatures, the base oil viscosity between a synthetic and a mineral, which are both the same viscosity at 40 degrees celsius, substantially diverge. Right. And so if you had quite a large divergence, you could very much see that a mineral NLGI zero would end up having kind of a thicker flow property than an NLGI one and a half that is a synthetic. So again, it's one of those things where, you know, we always talk on this channel about having to think through all the consequences of the choices that we're making. And in very cold temperature extremes, then lubricant selection, in addition to, you know, your pump and your line selection, it's all got to kind of work as one system.
[00:22:19] Speaker A: Yeah, that's. Yeah, that's exactly. Yeah. We need to consider all of the inputs here. The types of the pump, the reels, the hose size, the meters, and also the air pressure availability or the electrical power, hydraulic power type of product that you are, we are pumping. So it's really. Yeah. If you really want to make it smart and you really want to achieve, like, high results in the performance of your workshop or your automatic lubrication system. Yeah. You gotta really consider a lot of things.
[00:22:47] Speaker B: Yeah. Well, Danila, thanks very much, because that, I think, has been a really good session on just explaining the workings of the pumps and, you know, everything that has to be kind of looked at when we're talking to. About pumping of both lubricants and greasers. Now, keep in mind that it's not a simple exercise.
[00:23:04] Speaker A: Yeah.
