Otto Cuyler from Cuyler FoodPro talks to David about what to look for when buying a used jacketed stainless steel tank at auction.
About this segment of Blackbird TV
Recorded: September 21, 2020
Published: January 12, 2022
Otto Cuyler. my friend from Cuyler FoodPro, it’s a pleasure to have you on board, thank you so much. Thanks, David. If you could just describe what is a jacketed tank, and what’s important to know about that before you buy a used one? In the process industry, it’s not just food, as you know, but food and chemical and even pharmaceutical. There’s a wide use of tanks. For this conversation, we’ll talk about stainless steel tanks and to your question, we’ll talk about jacketed stainless steel tanks. Jacketed meaning that you have the tank itself, with the inner wall, which is stainless steel, then you would have an outer wall with a gap in there that’s essentially a jacket. And through that jacket, you can circulate cold water, steam, a variety of mediums, to either cool it or heat it. The jacket is under pressure and there’s varying pressures. If you just circulating like a cooling water through it, it might be 50 PSI which doesn’t require insurance, certification or validation. Once you get above 30, then they have to be certified by a certified welder. If you’re buying a jacketed vessel or tank, the number one thing is what is the condition of that jacket? Because what can happen is that, OK, it’s a 500 gallon jacketed tank. I need 500 gallons. It’s got the outlet that you need two inch, three inch, whatever it might be for your product, and I need to heat my product up to 180 degrees and hold it there. So the stuff that goes in the jacket is super hot and it heats it. It’s like it’s like a Crock-Pot. It’s a heat exchanger, essentially in a tank, in a tank form. Many of these types of vessels will have agitation, but I’ll get to that in a second. So the jacket itself needs to be certified assuming that we’re over 30 PSI, and the issue there is, how do you know if it will hold that pressure without a leak? If it leaks, you have to fix it, and it’s expensive because it has to be done by a certified welder. So we talked earlier about, you know, buying something that’s going to cost a lot of money: you’re better off making the investment up front. This is an area that is difficult for the auctioneer selling the equipment as well as the customer because they’re plumbed into place. And typically, the best you’re going to get is the mechanic that worked on that equipment or the maintenance supervisor will say “when we operated that last month, it was holding pressure fine.” That’s typically what you get, and that’s like buying a car and go, yeah, I just drove it to Buffalo and back, and it was fine. I know that it worked. I know that it works and I would say 95 times out of 100, that’s probably accurate, but it leaves room for interpretation. So the question is, if you want, if you if it’s really important and you’re talking about something very expensive, then you would want to get an independent test to send someone in there to do that. Otherwise, you’re taking your chance. Yeah. So essentially what they do is they’ll take that, they’ll block the ins and outs, they’ll put pressure on it with a gauge and they’ll see if it holds holds the pressure right? It’s a hydrostatic test as compared to an air test. OK. Because then you’ll be able to see where the water is coming out. OK, so that’s that’s a jacket, a tank, so many jacket it takes because there is a heat exchange on the outer surface of the tank. Or I should say, the inner surface. Actually, they’ll have a tank that has agitation so that you can take the hot product—assuming that we’re using heat—we’ll take the hot product away from the jacket. We’ll scrape it off, put it to the center and then expose new product to the outside. Therefore, creating better efficiencies to do that. So there’s an agitator up there that sometimes goes double motion with a gearbox on top, a shaft coming down an agitator assembly with scrapers. So you want to look down in there and you want to see if that’s bent or the scrapers are worn, or if there’s any gouges in the jacket as a result of the scrapers breaking down, they can wear the metal thin. That’s something that you can do visually if it shows a lot of wear, you should look closer. And then the gearbox is like any gearbox, you’re taking your chance with that. Unless you can start it up there’s really no way to validate that. That’s really about it. The jacket, the condition of the surface and then from a food safety standpoint, pitting, which is hard, you have to really get in close and look not necessarily microscopically, but you have to be able to look very closely at the surface or there again, pitting will will hold bacteria and will cause issues going forward. Yeah, that’s why the welds are so important in a food graded stainless steel tank because if you have bad welds, that’s a point that holds bacteria to your point. That’s exactly right. If, if you see, that’s a really good point, David. If you observe the outside of the jacket, if you see any repairs that were done on it, it’s a repair because there was a leak. Typically. If that repair wasn’t done by a certified welder, it has to be stamped. Repairs have to be stamped by a certified welder and identified on the vessel itself. So there’s a lot of questions to ask there and there again, it’s a buyer beware. And I think a sophisticated buyer is someone that knows what he’s looking at or get someone from a welding shop, the sanitary welding shop, to have a look at it for them. If it’s an expensive piece, that’s what I would do. Lots of really great information. Otto Cuyler, Cuyler FoodPro, Otto Cuyler, thanks for your time. David, thanks a lot. Thanks for having me.