Search results for query: *

I would like to know if there is any available data for the dynamic viscosity of normal saline at about 72 F? The CRC Handbook has some data for 5% solutions. I also have a published equation, which may be OK. Ideally, I would like to know if someone just has the number handy and/or can aim...

I would like suggestions for an alternative to the use of a linear spool valve for high pressure water flow control. The valve needs to direct seawater at a pressure which can alternate between a few psig to about 1000 psig. The flow rate is up to 200 gallons per minute. The linear spool valve...

unclesyd, Thanks a lot. Your idea may be a very good one, based upon our scale modeling of what is going on. It turns out that the cable may be rotating more than the cylinder itself. When you think about this, it sort of makes sense, since the cable has less mass and may have some built up...

Thanks again. The membrane/diaphragm will only separate two incompressible fluids which are at difference pressures. I do not think that needs to be reinforced at all, it just needs to be able to flex millions of times without failing due to fatigue. The best that I can come up with so far is...

Compositepro, Thanks for the Masterflex reference. The layflat tube that I want to use is intended to be a very thin plastic or rubber film, perhaps .010 or less in thickness. I will still check out the Masterflex material.

I am developing a water pumping type of application which will involve the use of an elastomer that acts as a diaphragm. The configuration of the diaphragm is not yet set, but it could be in the form of a cylindrical layflat type of tube. In its intended use, it will be cycled rapidly and...

GODHAN, It does stay vertical in the water column because it is cylindrical and has more weight on the bottom than top. This issues is rotation about the vertical axis. Thanks for the comment. Oceanman

Thanks for the advice so far. I only care about spinning about the the axis, as that seemed to be the problem on previous deployments. with the comm wire wrapping around the com cable. Yes, putting a swivel in one spot concentrates the wrapping close to the pivot point. Maybe something can be...

I have a pressure vessel test rig that I need to lower down to about 400 meters in seawater. It is pretty much just a 12 inch diameter pipe that is about 6 feet long. It has end caps, so the whole thing is pretty much cylindrical. There are a few things attached to its exterior, so it has a...

Thanks for all of the comments, and please keep them coming. I did wish to clarify a couple of things. The pump is in a pressure vessel at a depth of about 1300 feet below the surface. This makes venting airout a bit tricky. The low inlet pressures are possible only because the pump is in a...

Thank you for the post. I will try to respond to your questions as follows: 1) The pump in question, just to make sure we understand, is “wobble-plate” type – as opposed to a radial piston type – and is a positive displacement type. What is the make & model of the pump? What is the driver? I...

When pumping water at depth in our project, we sometimes degas the water. This air and sometimes water ends up inside of a small presure vessel. The volume of the pressure vessel is about 30 liters. It would be desirable to discharge the air and the water into the surrounding seawater. The...

We are using a small axial piston pump to pump several liter per minute quantities of water against a pressure head of about 600 psi or so. If the system has to start up against the full 600 psi, it seems to just go into a dry running mode of operation. If we gradually increase the back...

Warpspeed, So far, so good with the true sign wave inverter. It has not failed yet. I appreciate your other comments. Do you know who makes a compact dc to dc converter that will do as you suggest. Most of the ones I have seen are either the wrong voltage, or are really large. For now, I...

I thought that I would provide an update, which may put my issue to rest We installed the true sign wave inverter and it did not fail. We ran the motor for a few hours off of the battery pack without problems. Itsmoked, do you have a web or other reference for the 350 volt car project you are...

Dear All, Thanks for all the comments. We went ahead and ordered the pure sign wave inverter, and should have it in fairly shortly. I will try to provide more information to your additional questions on Monday concerning some specific questions. Yes, we are trying to pump water, but the...

Thanks, Itsmoked. I appreciate the comment about the motor start up. We had the VFD set for a "soft start" to elminate this problem. I will try a test, plugging the VFD into a wall outlet power source to test start up load using various motor start parameters. We are using an E500 series VFD...

Hi BigLe, Thanks for the comments. I can try to respond to your questions, as follows: Battery Pack: It was a lithium ion battery pack, three cells connected in series, for a nominal voltage of 12.6 volts. It was 100 amp hours. Failure Mode The motor ran OK the first time used. Upon shut...

We have set up a system to use a 12 volt battery to run a 3/4 horsepower 208 volts three phase motor. The system as currently laid out is as follows: A 12 volt lithium ion battery pack is used to supply power to a 2500 watt modified sign wave inverter which provides 120 volt AC power to a VFD...

Thanks ColinP. We are doing OK now with our computer program. Thanks for the thought on the dielectric fluid, it is a good one, but I think that our equipment would not do so well in it. Oceanman