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Summary: The design of genuinely waterproof containers is an arcane art but is reasonably doable if certain rules are adhered to which codify the underlying "magic". Failures occur when the basic sealing rule discussed below is violated. I.e. pressure on all sealing surfaces exceeds differential pressure at all times. In many products the failure is ...


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Well liners are generally made to order. One of your issues will be to find a company that can make what you want. You will need to ensure the liner is the correct size and that it does not tear when inserted into the well, while being filled with water, or when it is being removed from the well. You mention your wells are cased with concrete pipes. They ...


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I see two ways: I've had great experience in my pressure vessel design with a 2.3 mm thick liner of polypropylene or polyethylene. In a pinch, you can weld PVC, but I don't recommend it. Thinner stuff works as well, but the 2.3 mm allows you to place a weld bead on the edge using standard weld rod and plastic welding tools. If not, for a pretty ...


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The major factors surrounding failure points of waterproofing are, as has been said, the ingress of water around the main case opening and any I/O areas. For the main case opening, this ingress is usually mitigated by an O-ring. Due to the deformation of the O-ring under pressure, hard, 90$^\circ$ bends usually are the primary point of failure. This is the ...


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If you don't care it being a little flimsy and just want quick, and the plastic is not too brittle: Use a barbed fitting with a straight thread on the outside, e.g. #10-32 of M5x.8 (these sizes happen to be interchangable), and a sealant. SUMMARY: drill 4.2mm (work up size in small increments to avoid cracking) tap hole M5x.8 (or #10-32) (with great care, ...


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This sort of sliding seal is very difficult to achieve, especially when you have a square corner. Rotary engines have this problem and tend to accept a certain amount of leakage as inevitable and design around it. Changing the wheel profile to give it a more rounded shoulder would certainly help. One possible solution is an expanding seal, either an ...


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If you don't want to drill a hole on the box and mess around with nozzles and sealants, a solution would be to siphon water like The only difference is that that valve is going to be at the bottom side. The only "problem" is that you need to fill the hose. A common solution to that is


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The pressure at the depth of 100m is: $$p=\rho*h=100*1024=102400kg/m^2=10.24atm$$ Assuming 1 atm pressure inside the cabine. As per Roark’s Formulas for Stress and Strain WARREN C. YOUNG RICHARD G. BUDYNAS Seventh Ed. pp 502 ch. 11 table 11.4, for a square plate with free edge supports. $\beta=0.2874 \ for\ square$ $q=pressure, \ p $ $t=thickness,\ \alpha= ...


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The wavelength of the light with the dissociation energy of epoxy phenyl oxygen is 300-310 nm. Over time, when exposed to this wavelength, it will become opaque and yellow. The solution is simple: add a layer which absorbs strongly the UVa (it has a high absorptivity in these wavelengths), like oxanilidies, and this will inhibit the opaque degradation.


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I would guess that your current epoxy changes its optical properties because of ultraviolet (UV) light coming from the LEDs. You may be able to find specialized UV-stable epoxies that don't suffer from UV. You could rethink your mechanical design and use a glass (or UV-stable plastic, or sapphire) window in front of the LED. White LEDs are actually blue ...


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For a waterproof container to be useful, you have to be able to open it and put something inside. The most likely location for failure is obviously at the points where the case opens up. This is usually dealt with by using a rubber gasket which compresses slightly when the case is closed, creating a continuous seal between the two sides. The most likely ...


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Wood isn't a particularly waterproof material (it absorbs water & humidity), I would go for plastic or metal. To ensure the "waterproofness" of the case, I would suggest using an o-ring or similar foam gasket under compression, this is the best way to ensure it is sealed. Normally with o-rings, you would aim for a 20% compression. Now, there is the ...


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A lot of bearings are sealed anyway, at least to some extent, to keep the grease in and water and grit etc out. Equally the inner and outer shells are typically a press or adhesive bonded fit to the shaft/hosing so tend not to pose any inherent difficulties for sealing. Obviously the greater the pressure difference between the inside and outside the ...


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A common way to do this is to use mechanical fixings (bolts, rivets etc) and a flexible or semi-flexible gasket to provide sealing. Here the mechanical fasteners physically hold the plate on and also compresses the gasket between the two materials to form a good seal. Bolts are ideal for this as they allow quite fine adjustment of the clamping force so ...


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At the risk of performing a pure lmgtfy, take a look at this page An interesting quote from that page: The operation was started in 1825 and was halted a number of times when the river burst in and flooded the workings. Isambard Brunel was put in charge of operations, and at one time nearly lost his life in a flood. In November 1827 Marc’s son, ...


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take note if you are talking about dropping to the deepest parts of the ocean the pressure can be as high as 15,000 psi. the Yield strength of acrylic is maybe 10,000 psi. Your wall will be very thick! You can not use most of the thin shell based formulae you might look up. You can take an extreme view and imagine a large block of material with a tiny ...


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To be honest, if you need more precision than what the handbooks tell you, your best bet is to buy some o-rings and test them under the range of conditions under which you expect them to function.


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Being able to create a waterproof seal on a shaft would also have to take into consideration the water pressure on the outside of the assembly. In this case, waterproofing is more weatherproofing, reducing that aspect by a considerable amount. I suggest that your waterproof bearing, unless otherwise specified, is not a water-sealing bearing. If the ...


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You could make a water drain trap. Drill a vertical hole that meets the microphone hole somewhere along its length, with a drain hole sloping down for the water to escape. You could then make a step change in diameter in the mike hole (for example between the pink and blue parts in our drawing) to stop the water getting past the drain. Since you appear to ...


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I would say Thibd's answer excellent. However, one should look at the cost (including fabrication) on Monel, Incoloy 825, any Inconel or Hastelloy or Titanium . Although not "steel" they are metals that would answer the intent of the question. Also in "deep" water, corrosion of even carbon steel is not a problem because of low oxygen; but I think testing ...


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Small, waterproof electric motors are commonly available as electric outboard motors that run silently on 12VDC and are used by sport fishermen and also to power small sailboats into and out of harbors. You'd convert them to saw use by removing the propeller and replacing it with a circular saw blade which has been modified to fit onto the propeller shaft, ...


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I'd recommend first making a hole to fill the channels in the brick with mortar/concrete locally. This way you will effectively have a solid brick which allows for a much stronger fastening and a much larger range of applicable anchors. The anchors you show above are all mechanical anchors, which is not the optimal solution when a waterproof result is ...


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Pure weight test before and after may not be accurate as the enclosure may have absorbed some water without it entering. Apply dye around areas where ingress is possible, if it washed away there has been ingress. Depending on the volume/internal geometry of your enclosure a visual inspection is generally acceptable for IP ratings in my experience.


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Hydrostatic pressure is always looking for a tiny oppening, small scratches, nail holes, tiny tears, happened during the course of construction or due to wall settlement to find a way to infiltrate. There is only one expensive fix and that is to creat a space between the basement wall and interior wall with drainage on the bottom in between the two Walls to ...


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Based on limited studies, PVC can degrade underwater due to chemical and bio-microbe attacks, it can lose weight and become more fragile after an extended time. But under the same attacks, the cement can also have degraded and lost the bond with the PVC water stop. It looks like this is the case as the photo is shown - a stretch of watermarks tracing the ...


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Pretty sure they are not all stainless steel. I would expect some brass and I don't think I would expect the springs to be stainless steel. Different metals with water result in galvanic corrosion. And stainless steel can still rust. Also, water leaves behind residues and junk. And water provides resistance to the gears and mechanical oscillators so it would ...


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If your brick wall is constructed correctly it should have an air/moisture barrier inside the wall. Then you need to attach the flashings of your aluminum window to that barrier which is usually a continuous membrane by window weatherproofing tape available at home improvement centers and install a waterproof sill with proper details on the bottom of the ...


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The seal you are looking for is commonly called an oil rotary seal ring. I found many brands and sizes with a quick search. the range of prices for a 1-inch shaft is around $5.


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The solution you have suggested will not be waterproof for long. The reason is that, if you pull on the cable it will stretch and thin very slightly. This is enough to break the seal. If you can make the space, a cable gland is the best option. If you can't, and O-ring seal is probably the next best thing. Make sure to use a thick o-ring with some ...


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