Bottom drain line limit space

[aranoche]

Guys,

I have a problem with my rich glycol exchanger drain line. I have this vessel already stand above platform, and the space length from bottom flange (for drain) to floor is only 49mm. My piping engineer suggested to configure the bottom drain to be:
1. SS Blind ½ 150# with drill hole ½ FNPT
2. Male connector ½” OD x 1/2” NPT ,double ferrule,316 SS
3. Tubing ½” OD x 0.049” WT tubing seamless,fully annealed 316 SS, ASTM A269
4. Valve ½” OD,Ball , Double ferrule,316SS.
but still not enough space to install all above materials in 49 mm space.
how the best design for this very short space?

 

[chicopee]

Can you cut a trough or a holes in the platform?

 

[gr2vessels]

I also have a problem, I can't understand your exchanger configuration. Is the vessel the exchanger? Can you upload a sketch?

 

[LittleInch]

It would help if you could uplaod a sketch with distances, but why can't you just incorporate an elbow and bring the pipe out to the side?

Alos look up orifice flanges which include a small hole which goes out to the outside.

My motto: Learn something new every day

Also: There's usually a good reason why everyone does it that way

 

[racookpe1978]

You apparently have only 49 mm (less than 2" between the low point of the tank and the top of concrete (TOC).

Also, you apparently only need a small drain port, not a 1" line, 2" or 6 inch dia drain, right? (metric would be 25 mm, 50 mm, or 150 mm drain line, right?

If so, can you lift the tank temporarily or roll it over or tilt it sideways so you can get access to the bottom of the tank?

If your specification permit, drill and tap a 1/4 inch NPT (or 1/2 NPT) threaded female hole into the bottom of the tank. Screw in a Swagloc (or equal) street elbow into that NPT female-thread hole, aiming the Swagloc end of the street elbow towards your (future) drain connection on the top of the concrete. Put the tank back on its foundations, then connect up the 1/4 stainless tube drain tubing to the Swagloc end of the street elbow. Run the drain tubing - remember to anchor it into the concrete! against movement, and remember to protect the fragile 1/4 tubing against stepping damage and vehicle traffic. Remember to run the 1/4 tubing "always down" and put a 1/4 inch valve as close to the tank as possible to avoid freezing the drain line.

If all-welded connections are required. Do the same, put drill a hole into the tank at the drain point, but drill it to the OD of the 1/4 stainless ? pipe drain line. Pre-fab a <49 MM run of pipe down with a pipe bend and outlet stub to get clearance to get the pipe out from under the tank. Then add a drain valve etc. You will be by this time already needing a gouge into the concrete to get room for the body of the valve while maintaining a drain 'down" path. The stub length + pipe bend + pipe horizontal run may kink: you might need to try several times.

Alt: Ram the end of a butt-weld short radius 1/4 elbow into the drilled hole in the bottom of the tank, then fillet-weld the butt-weld elbow into the drilled hole with an external weld. It will "not quite" be right, but if the poor fitup internal crevices at the bottom of the tank (non-food service for example where trapping gunk and solids will not cause your design to fail) you will be able to keep your fluid from leaking out.

 

[SnTMan]

Like LittleInch suggests, drill one or more ports out radially thru a blind. Connect to it (them) in whatever manner suits.

Regards,

Mike

 

[aranoche]

gr2vessels : the vessel is rich glycol exchanger. And the photos attached on the link. The problem is at bottom nozzle which is already installed by flange, and can not be cut because of the fabrication certification (manufacture permit matter). The clearance reported from site is only 49 mm.
Along the discussion on my office, here is new configuration of the bottom drain:
1. SS 316, Blind ½ 150# with drill hole ½ FNPT , Reference ASME B16.5, thickness tf = 9.6 mm
2. Instrument pipe fittings, MALE ELBOW (Male NPT Both End), SS 316, Reference vendor HOKE : Length height is +- 36 mm
3. Instrument Valve ½” FNPT,SS 316
4. Male connector ½” OD x 1/2” NPT ,double ferrule,316 SS
5. Tubing ½” OD x 0.049” WT tubing seamless,fully annealed 316 SS, ASTM A269

I'm sorry I cant have the sketch. The document secured.

 

[chicopee]

No big deal, remove the existing flange by shortening its stub and weld a new flange or hammer out a trough in the platform.

 

[aranoche]

Here is the sketch I got from mechanical datasheet. The detailed CAD file is server secured.
Seems like we have mistake at the design (very short at the bottom), but I dont have deep understanding about vessel design.
If we use tubing and fitting to cover drain system, is it high or low possibility to occur a clogging from the debris/ solid material from condensate? because 1/2" tubing is smaller than 1/2" pipe. And the fitting is small also.

 

[racookpe1978]

Several different simple solutions are possible. Leave the expensive flanges as is.

Will they let you cut a "notch" in that grating to put a flange in the horizontal drain piping?

How far does the drain piping have to run, and (after it reaches the edge of the raised grating, does it have room to run down so a flange can be inserted there?

Where do you want your drain valve?

 

[gr2vessels]

According to the pdf sketch you have more than 49 mm, perhaps over than 60-70 mm. You should carefully establish every available milimeter of height.
Design and make one bolted thick blind flange (2" perhaps) to suit the nozzle. Drill a radial 1/2" hole on the edge of this blind to the centre of the blind. Drill a 1/2" hole in the centre of the blind to connect the internal exchanger space with this drain hole. Thread the radial opening to enable fit a threaded plug. Alternatively, weld a 1/2" flanged nozzle on the side of the 2" thick blind. Install the 2" blind and close the drain opening (threaded plug or 1/2" blind flange). Job done.

 

[aranoche]

gr2vessels yes, the clearance based on the design should be more than 49 mm. But the result as it already installed. The clearance became only 49mm. Finally, we put additional material for this bottom drain.
1. blind flange with drill hole 1/2" nptf (+/- 9.6mm)
2. elbow, 1/2" nptm (+/- 36mm)
then after elbow, we put ball valve, male connector then 1 m tubing with plug at the end (because we dont use permanent container for the drain fluid). in this situation, drain fluid will be flowed to portable container.
Is any problem with the configuration or any hazard will be occurred by those installation?

 

[gr2vessels]

You don't need the elbow if you drill a radial hole in the blind flange. If the blind is thick enough, you can weld on the edge of this blind a small flanged nozzle and connect to this nozzle all your drain piping, valves, etc. I personally don't like the threaded connection in the drain system, even if it is only 10.7 bar/230C rating.
Cheers,
gr2vessels