T/C Type J source?

[itsmoked]

Hello,

I am looking for a source of small Type-J thermocouples. Probably FEP Teflon but fiberglass would work too.

They need handle only up to 200C.

They have to fit into 0.082" diameter holes.

I would love a duplex jacket!

I need them in about 1 foot lengths.

I can find a bunch of this stuff on spools but I don't really want the hassle of welding the ends together myself a bazillion times. (unless someone tells me I can do excellent welds with a hot torch)

I have googled till my fingers bled... with no success. This is why I am asking you seasoned professionals..

Keith Cress
Flamin Systems, Inc.- <

http://www.flaminsystems.com>

 

[ko99]

They're not easy to find pre-assembled. I buy mine from Omega:

http://www.omega.com/ppt/pptsc.asp?ref=5TC&Nav=tema02

http://www.omega.com/ppt/pptsc.asp?ref=5SC&Nav=tema02

ko (

http://www.ecooling.biz)

 

[GTstartup]

You may not be able to weld them with a hot torch but there is such an animal as a T/C welder which kinda looks like a pair of needle nose pliers attached to a supply and a return path made of a block of metal. It works well and is super fast.

 

[itsmoked]

ko99; I looked at Omega but $39 a piece??!?! But on a second look from your link I see that that is for a 5 pack!

GT; I googled "T/C welder". I see what you're talking about and on a few of the links I found T/Cs available that are what I'm searching for... Figures.. Look for something else -> find what you're looking for.

Keith Cress
Flamin Systems, Inc.- <

http://www.flaminsystems.com>

 

[kontiki99]

I don't know your application, but you don't necessarily need to weld the TC junction. You can mate the two TC wires with a twist and use a crimp splice to hold the wire pair together.

You may need to consider time in service and environmental issues, like vibration levels, high winds etc.

In aviation a crimped splice installed using dimensionally calibrated ratcheting type crimpier is preferred over soldering and considered to give you 100% the strength of the wire.

The only thing you don’t want to do is apply install the splice in a manner that puts a third material between the two TC wires.

 

[VEBill]

We tightly twisted the TC wires and then silver soldered. Then we checked the calibration with deionized ice water and deionized boiling water and they were all fine.

 

[IRstuff]

Does it have to be type J?, Physitemp makes type T probes (IT-1E) that are 0.025" with 5 ms response times and are implantable. They usually ship with syringes and needles.

http://www.physitemp.com/temp.htm

Minco made a VERY samll PRT, S200PD

TTFN

 

[itsmoked]

kontiki99; The problem with a crimp is the hole "0.082" dia.
That would be a dang small crimp!!

Hey VE1BLL; That's interesting. Do you have any lifetime info on those joints? What temp? How long did they last?

IRstuff; Yes the product design is pretty much done. Forward and Reverse tables are already coded in, tested, and working. I just have one T/C now and it doesn't fit in the correct orifice. I rather fear implantables will be more expensive because of wording (i.e. implantable)

Keith Cress
Flamin Systems, Inc.- <

http://www.flaminsystems.com>

 

[Pud]

Hi,


The hot runner systems used on injection moulding tools often use small diameter J t/c - you might try suppliers of these. Not sure if .082 dia available but some runners are very small overall for close space hot tips. They are also always (in my experience) sheathed.

Bare t/c junctions are usually available from suppliers of plastic moulding accessories; such as water fittings, screw tips, etc. Not sure of your geographic location otherwise would suggest some......

Also have had t/c bare juctions welded with plasma(?) argon arc - worked well, although as a previous poster, they ideally are resistance welded, and kit is available for do-it-yerself!


Rgds

Harry

 

[itsmoked]

Thanks Harry.

0.082" Really isn't very small. I believe any T/C made with 20AWG or smaller would work fine.

I'm in N. Calif. Any of these places have web sites?

Cheers,
Keith Cress
Flamin Systems, Inc.- <

http://www.flaminsystems.com>

 

[Pud]

Hi Smoked,

Have checked on UK prices as cannot find US sites, so had a look in catalogue - looks like your Omega bare juctions cheapest as hot runner type t/c is: e.g. .062" dia s/s 304, sheathed t/c with teflon leads is 40GBP! - even assuming 1GBP=1USD still looks v. pricey....

Rgds

Harry

 

[Pud]

Hi itsmoked,

Just had a thought - did you ever get your caps for the cap discharge welder? Sounded like it would make an ideal t/c welder!!!


Rgds

Harry

 

[itsmoked]

Hahaha Harry... You remembered that huh? Don't you know it! I keep thinking I could have used that on this too maybe..

I couldn't bring myself to the expense for the battery project so I followed the solder-it-advice (skogs). It had mixed success.

The HILTI drill pack with, like 17 NICADs, worked out fine. What a gruesome chore thou. Probably took 1.5hrs because the batteries are in a rubik's cube form and I believe are assembled in a different space-time continuum, non-euclidean space...

But it works fine. Now I have to steel myself to do the second HILTI pack.

The Sony laptop one.. With 6 LiION batteries was an unmitigated disaster. A very complex mess because they paralleled two cells 3 times to allow monitoring and and individual charge control. It was all packed into an insultingly small space with the battery tabs soldered INTO a narrow 8" long, 1/2" wide, charger board with at least 200 parts on it. Just as I finished carefully soldering it all together I notice some of the SMD parts(SOT23s) were missing. They had popped off at some point. I found them and verrrrrry carefully soldered them back on in their best guess locations. Got the whole mess back into its too small case, measured the power out on two of the 8 pins. Plugged it into the Sony and the Sony insisted there was no functioning battery pack available...

So I have about $80 worth of LION batteries that are useless to me....


Oh and thanks for the research!

Keith Cress
Flamin Systems, Inc.- <

http://www.flaminsystems.com>