Depending on the waves I get a fair amount of variation in the glass level as the water sloshes about. I have had mild bouts of water carryover. The Toledo promptly starts weezing like a kid with a cold to remind me that it doesn't appreciate this.
I think I need something to remedy this...
See sketch below - I have seen pictures of sometthink like #1 on a boiler. 2-3 are ideas for bent pipe to go in the bonnet of a vft. 5 is an idea to use a manifold with porcupine pipes for more surface area.
What do folks think about steam driers(mild superheaters) like this? What worked?
-CB
P.S. I realize I maybe confusing things. 1 is a steam dome or reservoir. Also there are things similar that are some sort of steam/water separator. And then 2-5 are driers/superheaters.
cyberbadger wrote:Depending on the waves I get a fair amount of variation in the glass level as the water sloshes about. I have had mild bouts of water carryover. The Toledo promptly starts weezing like a kid with a cold to remind me that it doesn't appreciate this.
I think I need something to remedy this...
See sketch below - I have seen pictures of sometthink like #1 on a boiler. 2-3 are ideas for bent pipe to go in the bonnet of a vft. 5 is an idea to use a manifold with porcupine pipes for more surface area.
What do folks think about steam driers(mild superheaters) like this? What worked?
-CB
P.S. I realize I maybe confusing things. 1 is a steam dome or reservoir. Also there are things similar that are some sort of steam/water separator. And then 2-5 are driers/superheaters.
Turrets are good, but I have a internal baffle to shield the steam output from the water and then run the steam pipe back into the top of the boiler something like your number 2 , only a couple of feet of pipe , seems to work well.
dampfspieler wrote:Your boiler is a VFT-type with a wet firebox and inner lagging, isnt it? I think it was built for normal use at a donkey or a workshop.
No, it was custom built for Nyitra. I came up with the idea based very loosely on large stationary VFT's with larger fireboxes - a Manning VFT. I let Jeff Lund at LundMachineWorks came up with the design based on my idea.
To protect the engine from a sizable slug of water carryover, or excessive priming in the boiler, which might occur with high boiler levels, or rough sea conditions rocking the boat, I have a separator fitted. A friend gave me a sizable whistle (from a full size locomotive), and sometimes when I overdo that device I can get significant priming.
On the Margaret S. I made a separator to protect against possible water carryover, made from a 3 inch Schedule 40 pipe, 12 inches long, with butt-weld end caps, mounted vertically. A tangential horizontal steam inlet is welded in place at 9 inch elevation, with vertical steam outlet at the very top center of the vessel, and a liquid outlet at the very bottom. The outlet is connected to a Sarco Thermodynamic Steam Trap, discharging to a reserve feedwater tank.
The sketches you have shown would not protect the engine from a sizable slug of water carryover, or excessive priming in the boiler. For protection you need a significant volume of available water storage,
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SEPARATOR B4 INSULATION
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Last edited by fredrosse on Sat Aug 19, 2017 4:14 am, edited 1 time in total.
fredrosse wrote:On the Margaret S. I made a separator to protect against possible water carryover, made from a 3 inch Schedule 40 pipe, 12 inches long, with butt-weld end caps, mounted vertically. A tangential horizontal steam inlet is welded in place at 9 inch elevation, with vertical steam outlet at the very top center of the vessel, and a liquid outlet at the very bottom. The outlet is connected to a Sarco Thermodynamic Steam Trap, discharging to a reserve feedwater tank.
The sketches you have shown would not protect the engine from a sizable slug of water carryover, or excessive priming in the boiler. For protection you need a significant volume of available water storage,
I'm wondering if I can do something like your 3" pipe x 1' mechanically. I don't trust my welds for pressure. I wonder if a pipe of sched 80 (or higher) would have enough thread engagement to accept the inlet?
Just a question, why is it ok to use sched 40 here for a separator, but not the piping around it per ASME code is sched 80?
I'm wondering if I can do something like your 3" pipe x 1' mechanically. I don't trust my welds for pressure. I wonder if a pipe of sched 80 (or higher) would have enough thread engagement to accept the inlet?
ANS: The steam inlet needs to be tangential, to give spin to the incoming steam/water mixture, so centrifugal force drives the more dense water to the outside of the separator, and then the water falls downward by gravity. Schedule 80 for the main vessel may have enough thickness for pipe threads on the inlet if it was not a tangential entry. With the tangential entry threaded entrance nipple would not work because several full threads would be needed per Code.
Just a question, why is it ok to use sched 40 here for a separator, but not the piping around it per ASME code is sched 80?
ANS: The ASME Code does not require Sch 80 for this Pressure/Temperature condition, Schedule 40 meets the stress requirements for the 3 inch vessel pipe as well as the 3/4 inch steam inlet pipe.
In general it is considered good practice to use Schedule 80 for the smaller piping (3/4 inch, 1/2 inch), as the small sizes are more vulnerable to possible mechanical damage than the larger (3 inch) pressure vessel. So if somebody accidentally steps on the 3 inch vessel, it will not be damaged or break off. If they step on a thin wall 1/2 inch pipe, it may break, badly burning the person. Another good reason for the heavy wall thickness for the small piping is corrosion allowance. If the 3 inch Schedule 40 pipe were to have, for example, 1/16 inch loss of wall thickness due to corrosion, the vessel would still be good for the design pressure/temperature. That same 1/16 inch corrosion on a thin wall small pipe might not be acceptable, since 1/16 inch is a relatively big loss on a small Schedule 40 pipe, and even more important when you consider the wall thinning that comes with threaded piping. So it is just prudent to use Schedule 80 here.
