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T-Rex Series Burner Information &
Trouble-shooting
Forward
First, let me state clearly that the T-Rex series of burners is the
most trouble free and low maintainence type of burner you can buy for your
high temperature heating needs. These burners are delivered by the US Postal
service, and what happens to them in transit can result in a misadjustment,
but more likely your problem relates to the way its installed or used by
the end user. I fully guarantee my burners to be free of materials or workmanship
problems, but I can not help with problems created by the way its employed
by the end user, other than what I am supplying in this trouble-shooting
page. If you have problems that extend beyond those discussed in this page,
please see "Technical Support" at the bottom of
this page. Thank you.
I have included information on other topics related to burners and forges,
other than just trouble-shooting related items. Please drop
to the bottom of the page for this information.
Burner Problems to Check For
The first thing to do is to determine if the problem you are experiencing
is in the burner, or is a result of the way its installed in your forge or
furnace. Your burner was fully test fired before being unassembled for shipment,
so you will have to reassemble it correctly if its going to work properly.
Here are a couple of things to check if your burner does not perform properly
in a free air environment...that means clamped in a vise for testing, not
mounted in your forge or furnace.
Be sure that there is nothing obstructing the air intake ports, the
interior of the burner tube, or the nozzle. Open the choke about 1/3 of its
range, turn the gas on at a low pressure setting, about 2 psi, and ignite
the burner at the nozzle carefully so as not to singe your hand. Let
the burner warm up for a couple of minutes, and then run it through a series
of tests at various pressures and choke settings. Slowly turn up the pressure
to 6-8 psi, and adjust the choke while observing the flame. You should be
able to watch it change from a greenish tinged flame at the more closed end
of the choke range, to a more bluish flame at the open end of the choke range.
Take a look at the flame tuning
image on Ron's web site if you have any questions as to how it should
respond to the changes in choke settings. If it seems to respond well, and
the burner flame changes from a very feeble output at low pressure, and closed
down choke settings, to a mini jet engine at high pressure settings
and open choke, the burner is functioning properly, and the problem is in
your installation, not in the burner. However, if the burner does not seem
to respond correctly, here are a few things to check, and the list is very
limited because there are not many things that can cause the burner to
malfunction.
1. As I mentioned at the beginning, look for any obstructions in the
body of the burner, or its nozzle. Remove any that you find and retest as
described above.
2. Check the jet tip location. Theoretically, it should be located at
"D/2" from the throat of the burner tube. "D" is the inner diameter of the
burner tube. So a 3/4" diameter burner tube would have a "D" value of 3/8".
This is a purely theoretical value however, and you should loosen the lock
nut at the rear of the burner air intake assembly and slide the jet in and
out slowly at various pressure to determine the best location. Lock it down
tightly after you are done. You will discover that the T-Rex burners are
fairly immune to problems with this setting, and will operate well over a
broad range of jet location settings. Adjust it for the best performance
at the pressure you will most often be using.
3. Check that the nozzle location is correct. It should have approximately
1-1/4" of nozzle exposure beyond the end of the burner tube for a 3/4" burner,
and more for larger burners. Loosen the lock screws and move the nozzle in
or out, while adjusting the pressure and choke, as you did for the
jet location test above, and determine the best location for the nozzle, based on the average gas pressure setting you will be using. The nozzle
is very sensitive to the gas pressure you are running the burner at, as well
as the choke setting, so you will need to work between both to determine
the best location to lock down the nozzle.
That is all there is to tuning or checking the burner. There is not
much to go wrong with these burners, and they will provide you trouble free
service for many years if they are not abused, or incorrectly installed in
your heating device, especially if you don't forget to close the choke completely
the moment you shut off the gas to prevent the burner from becoming a chimney
to vent the ultra hot gasses in the forge. I will provide you a few
more tips below that relate to the forge or furnace installation, and some
possible problems to look for there if your burner works fine on the free
air test, but not in your forge or furnace.
Installation Problems and
Tips
This will be a restatement of much of the information that can be found
on Ron's pages, but it may save you some time if I put it here as well. This
will not be a comprehensive treatment of the subject, so you will have to
refer to Ron's Forge Design
Page, or his Forge and Foundry
Page, if you need further information. Please do not contact me for problems
in this area. Thank you.
1. The first item, and a very important item to check, is your nozzle
placement in the forge wall. It should not penetrate into the interior of
the chamber. It will melt or burn off if it does. Have it set back into the
Kaowool, or rigid refractory, an inch or so, and continue the taper of the
nozzle flare through the refractory. The refractory should seal tightly around
the outside of the flare so as not to allow any gasses to pass either direction,
into or out of the chamber. If you have a rigid refractory shell, you may
want to consider not using a flare on the burner and casting the flare taper
right into the refractory. This will eliminate the problems associated with
high temperature degradation of the metal in the flared nozzle.
2. Because there is a very large increase in the total volume of the
gasses entering the forge, by a factor of 7:1, the volume coming out the
exhaust openings in the forge are far greater than the volume entering the
forge. If you have any restrictions, such as doors, or too small of an exhaust
port, the back pressure will cause the burner to operate in an erratic and
improper fashion. Be sure you are not causing back pressure on your
burner.
3. A forge chamber that is very long but of small diameter, 3-4", may
cause a back pressure problem, even if the end openings are big enough to
vent the chamber properly. Some knife forge designs can run into this problem.
Allow enough diameter for the burner flame to enter the chamber completely
and properly. It should not blast up against a chamber wall from close range.
This will also cause erosion of your chamber wall where the intense flame
impinges upon the refractory.
4. Although the burner may function properly, if the burner opening
is too close to the forge floor, so that the floor is directly impacted by
the blue cone of the flame, any metal placed in the flame will be in an oxygen
rich portion of the flame, and the raw unburned oxygen will cause scaling
problems. Allow enough burn distance to consume the oxygen. One of the big
advantages of nozzle initiation burners, like the Reil, EZ, and T-Rex series,
burners, is that the burn starts up in the burner, thus consuming the oxygen
earlier, and helping to prevent the oxidation that occurs with chamber burn
systems. Also, the temperatures will be higher because the chamber is not
receiving any cold unburned gasses, only the ultra hot fully consumed gasses
after the burn.
5. Another issue that may be a problem in your system is the regulator
and plumbing. A BBQ regulator will not work...hands down. Don't even try
using one unless you wish to set yourself up for failure. They do not deliver
the necessary pressure, nor the necessary BTU output. Get a high quality
Fisher, hand adjustable, regulator, or another of equal quality, not one
of the cheap Chinese clones that have become available lately. It should
have a pressure range of 5-30 psi. They will actually operate smoothly from
0-30 psi, but the liability involved with people using the regulator as a
shut off valve, if they list it as going to zero psi, is a problem that has
been solved by listing the bottom end pressure as 5 psi. Connect the
regulator to the burner supply manifold, for multi burner forges, or directly
to the single burner, with 3/8" or 1/2" diameter plumbing. You may use 1/8"
copper pipe for the short distance from a manifold to your burners without
flow problems. Be sure there are no particles of metal or other "junk"
in the plumbing, because the tiny jet in the burner can easily become obstructed
when the flowing gas carries a particle into the jet and it becomes lodged
in the orifice. It is a very good idea to blow the gas plumbing clear with
compressed air prior to final connection to the burner, just in case there
are some residual contaminates in the propane supply system. If you encounter
flow problems, check the jet orifice for particle obstructions. You can use
a torch jet cleaner, or any fine wire, to clear any junk from the pathway
if its not clear. Be careful not to damage the smooth surface
of the jet interior.
6. There are two more items I will mention, but only as a cautionary
note. The first involves burner position. There have been reports of burner
malfunction in atmospheric burners when they are mounted vertically in a
furnace or forge. This is not specific to the T-Rex line, but to all atmospheric
burners. Apparently a problem can develop when the rising hot gasses interact
with the down flowing gasses in the burner tube. I have been unable to duplicate
the problem when conducting tests, but that doesn't mean that it can't happen.
Be aware that vertical burner positioning can cause a problem that may cause
erratic operation or flame-out. The second item regards propane contaminate
deposition in the jet of the burner. Apparently some propane has more
contaminates than other propane, depending on its source. You may need to
periodically clean out the jet of your burner if your propane leaves a tarry
deposit over time. You will simply see a degrading performance over time,
but cleaning the jet tip will quickly bring your burner back to like
new performance.
I will add information to this section as it comes to mind. This part
of the page will deal with various items related to burner mounting, as well
as forge or furnace operation.
Burner Mounting Bracket/Holder
To mount your burner to your forge/furnace you will need to construct
a bracket that will allow the burner to be mounted and locked securely in
place. This image is one possible design that
you may wish to employ. The image is full scale, so is a large file. You
can modify it to allow burner mounting at angles other then perpendicular
to the surface of the forge shell by cutting the weld end to whatever angle
you desire. For melting furnaces, the burner is generally mounted tangentially
to the interior chamber wall to create an intense vortex, and to prevent
the flame from playing directly on the crucible. The collar is attached to
the furnace/forge by welding it to the steel outer shell. You can modify
the diameter of the collar to fit any of the burner models I have available.
Just be sure to allow enough clearance to pass the outer diameter of the
burner nozzle or you will have to attach the nozzle after mounting
the burner to the forge or furnace....not recommended.
For a far more economical forge, you should use an "idle/full" valve
arrangement so that you can instantly drop your forge to a quiet idle when
you are at the anvil, or tending to some other chore, such as a phone call,
etc. When you return to the forge, a simple quarter turn of the lower ball
valve instantly brings the forge back up to full heat. You will discover
that the forge will not lose its operating temperature when in idle mode
either. The idle/full schematic diagram is self
explanatory, and you can easily figure out how to adjust the upper and lower
gas pressures by using the needle valve and regulator for your particular
needs when starting your day at the forge. Although the schematic calls for
1/8" plumbing, you may want to use 3/8" for everything except the little
bypass that has the needle valve in it. If you are using more then one burner,
the larger diameter plumbing will provide a better fuel flow with less pressure
drop. (Note: Attach regulator to tank according to manufacturer's
recommendations, and locate your propane tank according to local code
requirements.)
Here's an example of a two burner arrangement with a separate valve for each burner. Note also that the regulator shown would be in addition to the regulator at the propane tank.
I offer a kit with a 0-60 PSI high pressure regulator plus the valves and everything needed ecxept 1/4" copper tubing for an idle / full burner control. See the ordering page for details.
A Note About Quality and Safety
Many guys like to "poor boy" it, cut corners, and spend as little money
as possible, when building a forge or furnace system. This is a verybad idea.
You are working with a potentially lethal substance,
propane, and cutting corners can only subject you to hardware failures that
would not be a problem with higher quality parts and materials. When your
life or health may be on the line, it is only prudent to buy only the very
highest quality hardware, both for the plumbing and the regulator. Any valves
should be rated for propane, and of the very best quality possible, such
as "Jomar Super Ball Valves." Do not use water system
plumbing from your local hardware store. Water and flammable gas are
not the same. A leaking valve could be catastrophic in an indoor shop. Using
high quality components that are rated for propane will generally be much
safer, the most cost effective in the long term, and will be far more satisfying
to use. If you bought one of my burners, you bought the best, please use
it in a device of equal quality.
Well, hopefully the above information has helped you to locate your
problem and correct it. If not, I am sorry I am not able to offer further
support beyond what I have posted here for problems that are not directly
a result of a problem in the burner itself. If you have a problem that is
a result of how you are using the burner, I can't offer technical support
in that area. If the burner has a problem burning in free air, feel
free to contact me. Thank you.
(Click icon to contact me)
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