Author Topic: Iranian vacuum kiln (Read 2753 times)

Den Socling · « **on:** January 14, 2006, 03:10:07 pm »

As I mentioned elsewhere, I have been corresponding with Dr. Behbood Mohebby from Iran. He had contacted me about vacuum kilns and has sent pictures of a kiln he has built. I thought some of you would like to see.

he's tryin'!

He also has a website. I just checked it and it's down but you should try to see it.
http://www.tmu.ir/wood
If you find it up, check out the trip to Farrahs Machinery or visit to Ferahs machinery or something like that. It's pictures of his kiln class visiting a conventional kiln installation. It's really a small world despite what the politicians try to do.

Den Socling · « **Reply #1 on:** January 14, 2006, 03:21:41 pm »

His website is up. Here's a link I would like to make.
http://www.tmu.ir/wood/TEMPs/Excursion-Afshar.htm
It is an excursion to Afshar's.

DanG · « **Reply #2 on:** January 15, 2006, 01:01:36 pm »

That's a neat looking kiln, Den. Is he using it as continuous, discontinuous, or does it work like Serg's rig?

Den Socling · « **Reply #3 on:** January 15, 2006, 01:41:17 pm »

It works kind of like Serg's kiln - like a 'steam vac'. Serg has enough vapor and air in the chamber for natural convection while Dr. Mohebby uses fans. You can see the fans mounted inside. That triangular shape on the outside is a belt guard for the fan pulleys. Notice also the two cylinder air compressor that he is using in reverse.

I'll invite him to join the forum.

serg · « **Reply #4 on:** January 15, 2006, 02:29:43 pm »

Hello!
I looked a site of the Iranian university. The information on quality of drying of vacuum is not present.
Den, you know that each drying chamber should dry all wood of the world qualitatively.
The result of drying gives the answer on quality:
1. W - % on length of a board

2. W - % on a stack top, a bottom,

3. W - % on thickness of a board

4. Is whether or not internal pressure(voltage)

5. Is whether or not internal cracks

6. Face cracks and the screw of a board

From the small information I have understood that they make updating a tree, bend it(him) at high temperatures?

The professor from Iran is desirable on a forum.

Sergey.

DanG · « **Reply #5 on:** January 15, 2006, 02:43:39 pm »

Please do invite him. That would be interesting.

I sorta figured that's how he's running it when I saw the fans. I'm beginning to think that may be the best way to go for guys like me, so we don't have to deal with such a large "absence of pressure." The equipment wouldn't be nearly as expensive.

Mr Hootie has a pair of tanks that would be great for that. They are 3' diameter and 32' long twin propane tanks from an old gas truck. They are welded together. Given their age and length, I'd be scared to pull them down to 28 Torr, but they may be ok at a lesser "non-pressure."

I see that Serg has weighed in while I was typing.

This is no longer a unilateral invitation for Dr. Mohebby. I hope he decides to join us in light of this International effort.

GF · « **Reply #6 on:** January 17, 2006, 12:59:59 pm »

Could you effectively vacuum dry lumber using a air compressor pump in reverse? I would be curious as to how much vacuum it could pull.

Den Socling · « **Reply #7 on:** January 17, 2006, 03:39:38 pm »

I have used a refrigeration compressor in reverse (meaning I connected to the suction side) and they will actually pull very low. A big problem, though, is water vapor getting in the oil. It makes a mess. If you ever looked at oil in an engine with a blown head gasket, you know what it looks like.

isassi · « **Reply #8 on:** January 18, 2006, 07:18:47 pm »

So I guess you would need a dryer or water trap of some sort? A regular dryer inline with a compressor, as in an automotive system would not work due to the large amount of water? Ok...I'll put on my propellor hat and sit and think...think think think...

....headache beginning...what are other thoughts?

Den Socling · « **Reply #9 on:** January 18, 2006, 07:39:57 pm »

Two suggestions. 1) Use a liquid ring vacuum pump that is affected less by water vapor and 2) use a tube and shell heat exchanger standing vertically in the pipe to the pump.

Fla._Deadheader · « **Reply #10 on:** January 22, 2006, 10:22:11 pm »

Hi Den
We are gearing up to start building a vacuum Kiln in Costa Rica. Found some Propane tanks at the airport. I have some vane type vacuum pumps. We used vane types on milking machines, and they were subject to water vapor from the warm milk and cleaning the pipingsystem. If a solenoid activated Valve was used to hold the vacuum, would the pumps work well enough to at least be certain the kiln is functioning correctly ?? Figure on the dis-continuous method, so, not so critical onvacuum and such.

Any new suggestions as to construction ??

Is is cold enough in Pa. to warrant a trip to CR for ya ??

Den Socling · « **Reply #11 on:** January 23, 2006, 09:21:13 am »

If you want to hold vac (and I would), a ball-type check valve will close the pipe line when the pump goes off.

Soleniod actuated valves can be used for a variety of applications but we have shifted to actuated ball valves with spring return.

During most winters, CR would be looking good. But next week I'm heading to New Zealand for a couple/few weeks. When I leave NZ, I'm going to Hawaii for a week. By the time I get back to PA, it will be close to spring time.

Jeff · « **Reply #12 on:** January 23, 2006, 10:54:59 am »

Den, I am an orphan looking for a good family to adopt me. $:-\$

Den Socling · « **Reply #13 on:** January 23, 2006, 11:03:58 am »

Well son, it looks like you could be a big eater.

Actually, I've heard from a lot of orphans and volunteers lately.

Jeff · « **Reply #14 on:** January 23, 2006, 11:43:25 am »

Well if big eater is a problem, I can diet.

Den, does your friend from Iran use the internet? Can he get on the forum? It would be interesting to have a forum member from there that can help us understand the business he is in and also as things unfold, an understanding of current events from his prespective.

Den Socling · « **Reply #15 on:** January 23, 2006, 12:08:14 pm »

Yes Jeff. I am trying to get him connected. I sent him a link and asked him to connect when he had time and he responded with his office ours.

But we're working on it.

Did you click on the 'excursion' that I linked above? His kiln class doesn't look like what many would expect. With current events, I like as many people as possible see our similarities.

serg · « **Reply #16 on:** January 23, 2006, 12:30:44 pm »

Hello!
I think the colleague from Iran wants to talk on a forum!

But I know that such totalitarianism and censorship!

To live under a cap, bad idea.

Sergey

Fla._Deadheader · « **Reply #17 on:** January 23, 2006, 04:26:59 pm »

Hope you enjoy your trip. I believe with the thread on dis-continuous vacuum, and reading Serg's input, we can get a kiln to work pretty well. Might need some assistance tweaking it, if you stay in touch on the forum. Thanks for all your information.

Nothing to stop you from penciling in a spot for next winter, though .

Den Socling · « **Reply #18 on:** January 23, 2006, 05:58:56 pm »

Harold,

Are you going to use Sergey's design. That's continuous vac but it's what we call a steam vac. You leave some air in the chamber and the placement of the heating loops and condenser set up an 'engineered convection'. (That's DanG's newly coined term from another thread.

)

I'd be glad to help you with any design but I have a feeling that there is a lot of potential for a 'simple' design using Sergey's. What Sergey lacks is process control and I could help you there.

Den

Fla._Deadheader · « **Reply #19 on:** January 23, 2006, 08:49:44 pm »

That's exactly what we are planning to do. I think we will use a fan to circulate the air from pulling a little more than half the air out. This wood is new to me for drying, and don't wanna chance messing it up. Too valuable.

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Author Topic: Iranian vacuum kiln (Read 2753 times)