Pressure Testing Main Tube


#1

Update Failure reached at 210 PSI.

Main tube pressure tested with machined endcap to 120 PSI.

Tube ID 3.736- 3.734 Inch

1/8 Inch O-ring

No Leak after 2 hours test.




#2

120PSI-- That's great!!

What did you do to put it under that much pressure?

Eric


#3

It's not pretty but it has a max. working pressure of 300 PSI thick aluminum housing. New old stock. On shop air for now until gage and safety release valve arrive 250 PSI setting.



#4

Great test 120PSI = aprox 270' depth


#5

Thanks


#6

Testing with air pressure always scares me! Air is compressible and like any spring has the capability to explode violently and with a lot of energy. Have you considered converting your set up to water? Water is an incompressible fluid and for pressure testing is way safer! One can find small, high pressure, hand operated pumps online that you can hook up to a standard garden hose click here . I have not used this brand before but you can find other hand pumps I'm sure that are cheaper and will perform the same task!

With a water pressure testing system if your Wilkerson ever malfunctioned catastrophically it would be a lot safer and less violent. Having said this, your safest choice-even with water, when it comes to pressure testing is Distance! The "BANG" from imploding volumes always makes me jump-even when I know it is approaching its crush depth!


#7

440' great test, I wonder what actually caused the failure, was it the tube or the end cap. Looks like the pressure forcing the end cap into the tube may have caused it to shear off the edges of the end cap.


#8

I did a similar design but machined aluminium caps and uses 3/8 wall acrylic tube, using a radial and axial seal its rated for 600mtrs SWD



#9

I see a connector sitting on the bench, is that a SeaCon connector. If not what is the type and price if you don't mind me asking. I have been looking for connectors myself.


#10

hi im buying them for about 43 dollars each, from MJ stewart, i actually work offshore so found these to be the best i was finding by the time you get potting compound and time wasted on sealing its cheaper to just buy subcon or impulse connectors


#11

Perfect thanks I just sent off a request for a quote to see how they price out from them. If they come in at that price range I am interested, so far the prices I have been getting are much higher. I will also check out Impulse Connectors.


#12

http://www.ebay.com/itm/170997615921?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649

I am filling the test chamber with water first so to minimize build up of air pressure.


#13

I am revising the design to thicken cap to tube mating surface and increasing radius.


#14

Thank you for testing Mark! Good job on the plugs as well.

Seeing your post reminded me of a photo I took a while ago meaning to post it to OpenROV:


From a local Lowe's Hardware Store (USA)

Wonder if it might be an option..


#15

@Merrick, Sweet! If that is plastic, it would be easy enough to drill a hole for the wire pass-through. The hull design might have to be widened slightly to accommodate the wing-nuts, but this could be a much simpler way to make an end cap, as well as a solution that would solve the problems some other posters had with slightly misshaped tubes.


#16

I will look at test plugs! Thanks


#17

If I can find it, maybe some hollow all-thread (like for lamps) could be used instead of bolt, so plug could be sealed, and have a pass through for wires.


#18


The plug fits! Probably will need some sort of gasket along the top lip of the plug, where it meets the acrylic cylinder edge, but this is just a guess. Not the quality of the machined plugs that Mark and others are making, but it might do the job, and for about $7 if you can find them..