Register to reply

PVC/plexiglass pressure cap

by elixirnova
Tags: pressure, pvc or plexiglass
Share this thread:
elixirnova
#1
Nov6-05, 01:14 AM
P: 12
Yes, I'm new here so forgive me if im in the wrong forums. I am currently assembling a submergable underwater camcorder housing of 6" diameter pvc pipe. I was wondering what is the diference between plexiglass and double strength plexiglass concerning the pressure it can withstand.

I am going to need to be able to submerge it at most around 2-3ft. I'm sure I can find information on what kind of pressure the water will exhert at 2-3ft below surface, but i don't have a clue what kind of pressure plexiglass itself can withstand. Also if anyone could inform me about double strength plexiglass, would it be any better, or is single strength plexiglass enough to withstand the pressure it will encounter?
Phys.Org News Partner Science news on Phys.org
Law changed to allow 'unlocking' cellphones
Microsoft sues Samsung alleging contract breach
Best evidence yet for coronal heating theory detected by NASA sounding rocket
Q_Goest
#2
Nov6-05, 05:33 AM
Sci Advisor
HW Helper
PF Gold
Q_Goest's Avatar
P: 2,903
Only 2 or 3 feet? Don't worry about it, you could make it out of your mom's best china and it would survive! lol If you take it down below about 100 feet, then you might want to do some calculations.
Danger
#3
Nov6-05, 12:45 PM
PF Gold
Danger's Avatar
P: 8,964
Unless there's some other reason that you need that kind of housing, you might as well just tuck the camera into a Zip Lock bag. It might not be optically clear enough for you, but it would certainly handle more pressure than you'll be dealing with. (Plus you can work the controls right through it without any mechanical connections.)

elixirnova
#4
Nov6-05, 02:40 PM
P: 12
PVC/plexiglass pressure cap

Well next time I'll remember to go grab a $.99 big bottle of Vess Cream Soda. And use it . But till then i guess ill sell a few of these to make back the $30 I paid for PVC pipe .

Another odd question but ever use pvc threaded caps? can they withstand pressure or are they vaunerable to leakage?
Q_Goest
#5
Nov6-05, 04:14 PM
Sci Advisor
HW Helper
PF Gold
Q_Goest's Avatar
P: 2,903
Threaded caps are fine, the vast majority are pipe thread. Just put a sealant on the thread and tighten down. There are all sorts of pipe thread sealant. One of the most common is Teflon tape, you just wrap the tape (not sticky) around the male threaded half like a condom and screw them together. I haven't had a complaint yet....
FredGarvin
#6
Nov6-05, 06:02 PM
Sci Advisor
FredGarvin's Avatar
P: 5,095
Make sure you wrap the teflon tape in the right direction!
mashsoccer
#7
Oct3-07, 06:37 AM
P: 4
I have a similar question as did the man with the plexiglass pressure camcorder. I am wondering how much pressure plexiglass can withstand because I'm doing a submersible project and I need to know if I could use plexi glass for any part of the outer hull of my submersible going down 1000 feet!!!Please help anyone
mashsoccer
#8
Oct3-07, 06:38 AM
P: 4
I dont know anything abot plexi glass
mashsoccer
#9
Oct3-07, 06:38 AM
P: 4
Anyone know anything
mashsoccer
#10
Oct3-07, 06:39 AM
P: 4
:buge ye:
FredGarvin
#11
Oct3-07, 08:35 AM
Sci Advisor
FredGarvin's Avatar
P: 5,095
The depth allowable is going to be a function of the hull thickness (among other things). How thick is your hull?

Just as a measure, at 1000 ft, the hydrostatic pressure is going to be about 430 psi.
brewnog
#12
Oct3-07, 02:25 PM
Sci Advisor
PF Gold
brewnog's Avatar
P: 2,794
Is Plexiglass another trade name for Perspex? I.E. acrylic?
FredGarvin
#13
Oct3-07, 08:26 PM
Sci Advisor
FredGarvin's Avatar
P: 5,095
Quote Quote by brewnog View Post
Is Plexiglass another trade name for Perspex? I.E. acrylic?
Pretty much. Yes.
Danger
#14
Oct4-07, 06:55 AM
PF Gold
Danger's Avatar
P: 8,964
While regular acrylic is very strong, it's prone to scratching and thus becomeing cloudy. If the environment in which you're going to be using it is in any way abrasive, I'd consider bonding it to the back side of a thin pane of glass.


Register to reply

Related Discussions
Static pressure vs. dynamic pressure Mechanical Engineering 19
Conceptual Pressure Question: Fluid Pressure in a U-Tube Introductory Physics Homework 1
Design pressure & max working pressure Engineering Systems & Design 7
Is reactive pressure as efficient as expansive pressure? General Physics 7
Vapour Pressure and External Pressure General Physics 4