The pipe fitting that you need for this application is commonly availible in Blighty and costs peanuts. It comes in BSP (British Standard Pipe threads ) sizes from 1/2 inch upwards and is used as a normal tank connection in both hot & cold water tanks. Threads are parallel and these connections are reliable. Strangely, pipe sizes have not been metricated here other than for copper pipe which has been adapted to the nearest metric unit.e.g. the old 1/2inch i.d. copper is now 15mm o.d.copper. Even the French use BSP pipe fittings!
I am not sure what standard pipe thread you use but if it is American Standard Straight Pipe thread, then these look compatible. eg. 1/2inch and 3/4 are both14 tpi in both systems. The point of all this is that if you can use BSP flanged fittings for tank connectors the I will arrange to ship them to you at cost to save you farting around with brazing. email me direct on [EMAIL PROTECTED] ken --- -- Original Message ----- From: <[EMAIL PROTECTED]> To: <biofuel@yahoogroups.com> Sent: Sunday, January 19, 2003 5:55 AM Subject: [biofuel] Re: Drum Modification > I've been thinking about the weldless approach a lot lately as I just made some new processors (I demo'ed one at the > huge anti-war rally in san fran today, I played around with a 12V pump for an agitator (not a good enough one > though it did make some biodiesel while we ran our mouth about how others should too), showed off the anti-war > machine, flew banners off of our cars and trucks, and otherwise made fools of ourselves along with a contingent of > other biodieslers. > > Anyway I think there are times when a weldless approach is preferable and times when brazing in fittings makes > more sense. > > I was fooling around trying to figure out some cheap variations on processor design, pushing the bung-side-down > and weldless approach as far as I could take it. I have an excess of closed head drums available which is an unusual > factor- I got to cut some of them up just for the bungs, and then played with attaching the bungs to other drums... > > (After two or three months of processor experimenting, I have developed some kind of obsessive disorder or > something- I visualize plumbing stuff and weldless processors in different configurations all day and allnight in > my head- I dream about these things, I notice that no matter what I am doing, in the backof my consciousness I seem > to have some kind of visual of fittings, drums, and pipe layout configurations running through my head. I REALLY > need to get a life! really!) > > Having just gone through all of the options I could think of I'm pretty convinced of the following: > > 1. if you want to go weldless for a 'starter' processor, use the bungsidedown approach (I don't believe plastics are a > good idea at all for processors, having watched my friend melt a plastic tank processor, and watched a lot of others > leak) > > 2. brazing is the easiest way for an amateur metalworker to attach fittings to the thin metal of a drum with the > least risk of leaks > > 3. various compression-fitted connectors spring leaks (and I've as I said experienced this a lot) > > 4. One problem with the male-female connector approach is that (in the US at least) pipe thread is tapered. SO > there aren't a lot of ways to get a really tight fit with standard plumbing parts- you can screw two plumbing > fittings together but they'll bottom out before there's enough contact to make this a safe way (using commonly > available gaskets) to put a fitting on the bottom of a drum that will contain 400 pounds of hot biodiesel. Bungs, by > the way, do not seem to be tapered. THis allows for a pipe thread to be extended quite far through a bung, at which > point you can attach more plumbing to the protruding threads on the inside of the drum- there's times when this is > useful, dip tubes and other intakes inside of drums, heat exchangeers, and more. There ARE a couple of 'nuts' that > screw on to pipe thread, and can be run further than most other fittings- one is just a pipe thread nut that can be > difficult to find in hardware stores and isn't used often in plumbing, and the other is a lightweight lockring from > electrical conduit fittings- the lockring/nut (cant remember actual name) that you tighten inside an electrical box > in EMT or rigid applications is threaded like pipe thread, and this is useful for light-duty applications with a > gasket. > > If you spend money to send away to a catalog place for a gasketed spigot adaptor (they do make a few things like > this- it;s a fitting that gets a lockring and an gasket -ring, I haven't been albe to find a good one locally, though > MacMaster-Carr has them I believe) you might as well spend the same money on getting some local shop to braze a > fitting on for you so that it will be permanently leakproof > 5. However if you just need a place to stick a fitting above the liquid level- ie the top of your sight tube, or a > return from a pump in a pump-agitated processor- screwing plumbing fittings together on either side of the > drum's sheet metal with some gasketing material to take up the slack is fine- just don't expect it to be totally > fumeproof without serious gasketing. This is the light duty application I just referred to. > > 6. We got some bungs brazed to the bottom of a 110-gallon tanks and our welder saint used rivets in addition to the > brazing, for the added security (and epoxy coating to insure it was all as liquidtight as could be. ) seems that it > could b e problematic unless the rivets are steel- pop rivets are usually aluminum I believe. > > 7. Silicone is a decent sealant that I think is biodiesel-proof. I still wouldn't use it as a gasket for a fitting that has > all of that pressure/weight on top of it, but it's good for sealing light-duty fittings up above the liquid level. I just > used it for stuff attached to the top of a closed 'barrel-based, bungside down' processor- to help contain the fumes. > Mark > > --- In biofuel@yahoogroups.com, "hugh_frater <[EMAIL PROTECTED]>" <[EMAIL PROTECTED]> wrote: > > > > > What about using a male & female threaded connecters with O rings? Just > > > flatten a small area of the drum put an O ring on the male > > connecter, slip > > > the connecter through a hole in the drum that is just barely big > > enough for > > > the connecter to fit in, another O ring, then screw on the female > > connecter > > > and tighten. > > > > > > Greg H. > > > > > > Biofuel at Journey to Forever: > http://journeytoforever.org/biofuel.html > > Biofuels list archives: > http://archive.nnytech.net/ > > Please do NOT send Unsubscribe messages to the list address. > To unsubscribe, send an email to: > [EMAIL PROTECTED] > > Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/ > > > Biofuel at Journey to Forever: http://journeytoforever.org/biofuel.html Biofuels list archives: http://archive.nnytech.net/ Please do NOT send Unsubscribe messages to the list address. To unsubscribe, send an email to: [EMAIL PROTECTED] Your use of Yahoo! Groups is subject to http://docs.yahoo.com/info/terms/
