1 Steam Cars : Phorum
General Steam Car topics
Oil in Condensers
Posted by: Peter Heid (IP Logged)
Date: August 16, 2003 11:46PM
<HTML>I have noticed in my books on heat exchanger design that the performance of a condenser with a smooth interior is enhanced as many as 20 times by the introduction of small amounts of oil in the system. It seems on a smooth surface that film condensation will prevail until a bit of oil helps the coalesing of water droplets and hastens their flow. The insulating ability of the thin film of oil is insignificant compaired to the film of condensate that forms during film condensation. This does not mean globs of 600 weight cylinder oil emulsions should be allowed to reach the condenser but some clean oil is beneficial.
Peter Heid</HTML>
Peter Heid</HTML>
Re: Oil in Condensers
Posted by: Jim Crank (IP Logged)
Date: August 17, 2003 01:48PM
<HTML>Peter,
The important key word is THIN.
Some condensers worked a lot better with a very thin coating of Teflon, again the word is THIN.
The whole idea is to prevent the water film of the condensing steam from forming on the walls of the condenser tubing; but to form droplets that fall, or are blown, away. A surfactant does the same thing; but unfortunately does not work when put into the feedwater of a steam car, due to superheat steam conditions. Worked on this once for a group that wanted to improve the throughput in seawater to drinking water conversion plants. One molecule thick Teflon coating was a very close second choice to a surfactant, and didn't require being added to the feedwater of the evaporators.
Jim</HTML>
The important key word is THIN.
Some condensers worked a lot better with a very thin coating of Teflon, again the word is THIN.
The whole idea is to prevent the water film of the condensing steam from forming on the walls of the condenser tubing; but to form droplets that fall, or are blown, away. A surfactant does the same thing; but unfortunately does not work when put into the feedwater of a steam car, due to superheat steam conditions. Worked on this once for a group that wanted to improve the throughput in seawater to drinking water conversion plants. One molecule thick Teflon coating was a very close second choice to a surfactant, and didn't require being added to the feedwater of the evaporators.
Jim</HTML>
<b>Re: Oil in Condensers</b>
Posted by: JW (IP Logged)
Date: August 18, 2003 02:52AM
<HTML>Hmmmm, I guess Tide in the condensor is not a good idea?
My friend Jeff in Texas bought a 1920 condensing car from Carl Amsley who instructed him to add a palm full of Tide to the condensor with water for each days run. Detergent may have had some temporary beneficial effect, but I urged Jeff to discontinue this practice as it seemed that the residue would eventually end up on the internal evaporating surfaces.
The old boiler did develop multiple leaky tubes on the crown sheet, and we replaced the old 23 inch boiler with a 26 inch ...and new separator the following year.
The car now generates plenty of reserve steam.
One interesting observation on the old boiler was the dome effect on the top sheet It was a gradual but very visible dome from the shell to the center of the top sheet that was at least a 3/4 inch rise.
Do tubes just stretch that much? .....I guess so. What do you think, Jim?
JW
-admin-</HTML>
My friend Jeff in Texas bought a 1920 condensing car from Carl Amsley who instructed him to add a palm full of Tide to the condensor with water for each days run. Detergent may have had some temporary beneficial effect, but I urged Jeff to discontinue this practice as it seemed that the residue would eventually end up on the internal evaporating surfaces.
The old boiler did develop multiple leaky tubes on the crown sheet, and we replaced the old 23 inch boiler with a 26 inch ...and new separator the following year.
The car now generates plenty of reserve steam.
One interesting observation on the old boiler was the dome effect on the top sheet It was a gradual but very visible dome from the shell to the center of the top sheet that was at least a 3/4 inch rise.
Do tubes just stretch that much? .....I guess so. What do you think, Jim?
JW
-admin-</HTML>
Re: Oil in Condensers
Posted by: Jim Crank (IP Logged)
Date: August 18, 2003 02:21PM
<HTML>JW,
Putting soap in the feedwater of a steam car is about the dumbest thing one can do. The foaming and priming would be awful until it was finally gone. Yes, it would form crud on the crown sheet if you put in a lot of soap.
Sure it would wash away the condenser oil inside; but so will plugging up the outlet on the bottom and storing the car with kerosene in the condenser, then washing it out. Same for the boiler in a condensing car.
That is how I clean Doble condensers, connect both ends with a tank and pump and then pump kerosene through the honeycomb backwards for a day or so. Then wash it out. Also put a gallon of kerosene in the water tank when storing the car for a while, then washing it out with all the residual oil.
In fact, when storing my old White for a while, I always drained and flushed the whole system and then put in five gallons of kerosene and let the car stand with the entire system filled with kerosene. The amount of oily crud that came out was astonishing. That old coil stack lasted for eighty years too.
I have seen lots of old Stanley boilers with domed top sheets, seems to be something they do over time. The tubes do stretch and they also, I think, extrude towards the inside a bit on both ends, reducing the amount of tubing that is held in the sheets.
Jim</HTML>
Putting soap in the feedwater of a steam car is about the dumbest thing one can do. The foaming and priming would be awful until it was finally gone. Yes, it would form crud on the crown sheet if you put in a lot of soap.
Sure it would wash away the condenser oil inside; but so will plugging up the outlet on the bottom and storing the car with kerosene in the condenser, then washing it out. Same for the boiler in a condensing car.
That is how I clean Doble condensers, connect both ends with a tank and pump and then pump kerosene through the honeycomb backwards for a day or so. Then wash it out. Also put a gallon of kerosene in the water tank when storing the car for a while, then washing it out with all the residual oil.
In fact, when storing my old White for a while, I always drained and flushed the whole system and then put in five gallons of kerosene and let the car stand with the entire system filled with kerosene. The amount of oily crud that came out was astonishing. That old coil stack lasted for eighty years too.
I have seen lots of old Stanley boilers with domed top sheets, seems to be something they do over time. The tubes do stretch and they also, I think, extrude towards the inside a bit on both ends, reducing the amount of tubing that is held in the sheets.
Jim</HTML>
Re: Oil in Condensers
Posted by: George Nutz (IP Logged)
Date: August 18, 2003 04:28PM
<HTML>Jim,
I had read in boiler treatment books(and have used) a small amount of trisodium phosphate in the water tank when filling to get the PH buffered plus it is a tremendously powerful cleaner. Up in this part of the woods the well water can have the PH of vinegar and a very small amount will move it into "basic" territory. I would not use it in a monotube as it would turn to its granular condition if going thru a superheated pipe, on the Lamont and on a Stanley it would stay in solution and keep the boiler clean. Have you used it or have anything to say about it?
I would think on the Stanley sheets the bulging would eventually happen with copper tube boilers. Ed Gallant had a number of boilers in his shop and he had a few old boilers that were concave that were steel tubed as the tubes must have been rolled from the perimeter to the inside in circles. Running a copper tube boiler @600psi+ with a large firing rate would probably result in the soft copper tubes extruding over time, the tube sheets, being like swiss cheese in terms of rigidity would go right along with it!</HTML>
I had read in boiler treatment books(and have used) a small amount of trisodium phosphate in the water tank when filling to get the PH buffered plus it is a tremendously powerful cleaner. Up in this part of the woods the well water can have the PH of vinegar and a very small amount will move it into "basic" territory. I would not use it in a monotube as it would turn to its granular condition if going thru a superheated pipe, on the Lamont and on a Stanley it would stay in solution and keep the boiler clean. Have you used it or have anything to say about it?
I would think on the Stanley sheets the bulging would eventually happen with copper tube boilers. Ed Gallant had a number of boilers in his shop and he had a few old boilers that were concave that were steel tubed as the tubes must have been rolled from the perimeter to the inside in circles. Running a copper tube boiler @600psi+ with a large firing rate would probably result in the soft copper tubes extruding over time, the tube sheets, being like swiss cheese in terms of rigidity would go right along with it!</HTML>
Re: Oil in Condensers
Posted by: Peter Heid (IP Logged)
Date: August 18, 2003 11:20PM
<HTML>Yes, Jim thin is the key word. The other part of the equation is the smoothness of the condensing surface. A smooth surface makes greater gains with a thin oil film, as much as a 20 fold increase over un-oiled surfaces. The book I was looking at even had pictures and the surfaces they were working with were almost a mirror finish and the oil film was invisable to the naked eye.
I just wanted to make the point that complete separation is not critical with oil that doesn't break down or emulisfy, a bit in the condenser could be benifical as long as it stays there.
Peter Heid</HTML>
I just wanted to make the point that complete separation is not critical with oil that doesn't break down or emulisfy, a bit in the condenser could be benifical as long as it stays there.
Peter Heid</HTML>
Re: Oil in Condensers
Posted by: SSsssteamer (IP Logged)
Date: August 19, 2003 02:37AM
<HTML>Dear George, I have used TSP for years in our Stanleys. About every third time that I take out one of our Stanleys, I will put about a palm full of TSP into the water tank. That evening when you blow down, you can see the difference in the blow down water. It looks like used dish pan water with all of the crud from dinner that is leaving along with the water. Our PH level here is about 10. TSP does a good job of cleaning out all of the calcium and other deposits in our noncondensing cars. In our condensing Stanley we get the same results except that the blow down water will look more like dark tea. Tri sodium phosphate is avaiable in about any hardware store in the paint department. In the past, I have scorched a few boilers, and usually after a good scorch, the tube sheets are not flat anymore. :-( Usually they have the curves of a potato chip after a good hot scortch. They still hold tight, but they look like hell.</HTML>
Re: Oil in Condensers
Posted by: Dick Vennerbeck (IP Logged)
Date: August 19, 2003 01:32PM
<HTML>Peter,
I seem to remember reading someplace that Teflon coating would do the same thing as you decsribe in a thin oil film on the inside of a condenser.
It would be very difficult to teflon coat the Stanley condensers however some other type of hydrophobic surface may also work. Any Idea's?
Dick</HTML>
I seem to remember reading someplace that Teflon coating would do the same thing as you decsribe in a thin oil film on the inside of a condenser.
It would be very difficult to teflon coat the Stanley condensers however some other type of hydrophobic surface may also work. Any Idea's?
Dick</HTML>
Re: Oil in Condensers
Posted by: Jim Crank (IP Logged)
Date: August 19, 2003 02:03PM
<HTML>George,
Certainly TSP works very well in cleaning a boiler. What I wish I had paid more attention to, is what Besler did for his commercial steam generators, in terms of water treatment. His literature doesn't mention this.
The degree of water treatment that I have seen in big powerplants was very educational. They really take great pains to see that the Ph, dissolved solids, carbonates, etc., is just where they want them, and on a continual basis. Unless the water one uses is really acidic or basic, I can't see testing it while on the road, although I do have a little Ph tester.
Allen Brasel keeps his Stanley boiler full of kerosene when he stores it and the crud that comes out when he washes it out before running the car is eye opening. It seems to work and that boiler is probably 25 years old and steams perfectly, nary a leak. I pump kerosene into the Doble's coil stack when I am going to leave the car standing for a few months.
Becker never worried about it with E-14 and he would get maybe 20 years out of a coil stack and even then we would only replace the superheater and maybe one or two coils down from there. I added blowdowns on both ends of the coil stack on E-23 and blast it down from each end after each run. That trick I learned from Roland Giroux and his vast experience with Whites. His theory, gleaned from the factory mechanics in L. A., was that it was still rather soft, and blowing down each time would scour it out. When I got the car that coil stack was 80 years old, so I figured there must be something good in doing that, and also adopted the idea.
The problem with Doble and White monotubes is that miserable carbon.
I think this winter I am just going to have to design and install a really good separator for the exhaust steam going into the condenser and after the fan turbine, the oil lubricates it's bearings.
Now that I recall, those bulged boilers were indeed copper tubed, and I think your theory is right. The copper stretches and the sheets follow along.
Jim</HTML>
Certainly TSP works very well in cleaning a boiler. What I wish I had paid more attention to, is what Besler did for his commercial steam generators, in terms of water treatment. His literature doesn't mention this.
The degree of water treatment that I have seen in big powerplants was very educational. They really take great pains to see that the Ph, dissolved solids, carbonates, etc., is just where they want them, and on a continual basis. Unless the water one uses is really acidic or basic, I can't see testing it while on the road, although I do have a little Ph tester.
Allen Brasel keeps his Stanley boiler full of kerosene when he stores it and the crud that comes out when he washes it out before running the car is eye opening. It seems to work and that boiler is probably 25 years old and steams perfectly, nary a leak. I pump kerosene into the Doble's coil stack when I am going to leave the car standing for a few months.
Becker never worried about it with E-14 and he would get maybe 20 years out of a coil stack and even then we would only replace the superheater and maybe one or two coils down from there. I added blowdowns on both ends of the coil stack on E-23 and blast it down from each end after each run. That trick I learned from Roland Giroux and his vast experience with Whites. His theory, gleaned from the factory mechanics in L. A., was that it was still rather soft, and blowing down each time would scour it out. When I got the car that coil stack was 80 years old, so I figured there must be something good in doing that, and also adopted the idea.
The problem with Doble and White monotubes is that miserable carbon.
I think this winter I am just going to have to design and install a really good separator for the exhaust steam going into the condenser and after the fan turbine, the oil lubricates it's bearings.
Now that I recall, those bulged boilers were indeed copper tubed, and I think your theory is right. The copper stretches and the sheets follow along.
Jim</HTML>
Re: Oil in Condensers
Posted by: Peter Heid (IP Logged)
Date: August 19, 2003 07:31PM
<HTML>Dick,
There is a coating called Xylan that you spray on, it has a teflon like feel and it is very tough. The last time I saw it was about 1996 in an industrial supply catalog, but I have not looked since. I mentioned it in my separator paper briefly for the purpose of keeping internal surfaces clean. I don't know how thick it goes on or what kind of heat transfer rate it has. Xylan is a trademark I believe.
Luck, Peter Heid</HTML>
There is a coating called Xylan that you spray on, it has a teflon like feel and it is very tough. The last time I saw it was about 1996 in an industrial supply catalog, but I have not looked since. I mentioned it in my separator paper briefly for the purpose of keeping internal surfaces clean. I don't know how thick it goes on or what kind of heat transfer rate it has. Xylan is a trademark I believe.
Luck, Peter Heid</HTML>
Sorry, only registered users may post in this forum.