Warning:
Read and follow all labels in the Owner's Manual. Smith Equipment
has been manufacturing top quality oxy-fuel equipment since 1917. Smith products are safety
engineered, 100% tested and made in the USA. Miller Smith Equipment presents: "Oxy-Fuel Equipment
Operation and Safety" video. Hi, I'm Jack Mortenson, and today we're going to talk about safety. We've divided our presentation
into a series of segments so that we can focus in on various aspects of the safe handling and operation of oxy-fuel cutting, welding
and heating equipment. Why are we doing this? Because unfortunately each year there continue to be injuries, property damage and even loss of life as a result of improperly
handled oxy-fuel equipment and compressed gas cylinders. No matter how experienced you may become, never lose sight of this one simple fact, oxy-fuel equipment
always has the potential for disastrous consequences and therefore proper
handling is a necessity. And remember, for safety's sake, don't give accidents an opportunity. Now we all know that
violating safety principles doesn't always cause
property damage or injury, but just when you let your guard down, in that moment of time, your life or your coworkers'
lives could be changed forever. Oxy-fuel safety involves
a conscious decision to understand the principles involved and it requires the ongoing
choice to follow them. After all, everyone has the
right and the responsibility to be safe in their workplace. To help better understand the safety rules for handling oxy-fuel equipment, let's begin by reviewing the
fundamentals of combustion. Well, in order to have combustion, you need three basic elements: fuel, oxygen and kindling temperature — and if any one of these
elements isn't present, combustion will not occur. Let's take a look at
how a common match burns in relation to the triangle of combustion. The fuel for combustion is
the sulfur on the match head. The sulfur has a very
low kindling temperature which is obtained by heat from
the friction that's created when the match is rubbed
across an abrasive surface. The oxygen needed for combustion is available in the air we breathe which is about 21% pure by volume. The process of cutting
steel is actually the same. It's a burning process,
but for steel to burn you need more than simple
atmospheric oxygen, you need to achieve the extremely
high kindling temperature that can only be produced in a
very pure oxygen environment, which is then mixed with a fuel gas, and that means oxygen of
greater than 92% purity needs to be applied to the steel in order to heat it to
its kindling temperature, which is approximately
2,200 degrees Fahrenheit. Let's take a look at
a simple demonstration of how the purity of the oxygen can affect the kindling
temperature of steel. Notice how this piece of steel wool burns using this small candle
and atmospheric air. Now, let's see what happens when pure oxygen is introduced
into this combustion process. As you can see the
greater the oxygen purity, the faster and hotter the fuel will burn. High purity oxygen also
has another effect. It lowers the temperature at which all fuels will start to combust. Gases in the welding
industry are all pressurized and they're available in
different sized cylinders. Each cylinder must be clearly labeled to show the cylinder testing date and often it will show the gas
distributor's name as well. Each gas cylinder must also be labeled to indicate exactly
which gas is stored in it as well as the type of hazard
that may be represented. Now some gases represent
a combination of hazards and there's no industry standard for color coding of
industrial gas cylinders, so here's an important safety reminder. Always check the cylinder label. Now let's talk about some
of the other safety rules for handling pressurized cylinders. The first item on our checklist
is when they're not secured, cylinders should always be kept to protect the cylinder's valve. If a highly pressurized cylinder were to fall without the valve protected, the valve itself could break off, and with the high pressure being expelled from the cylinder valve, it could be propelled
like a powerful torpedo in any direction, creating
a very dangerous situation. Well, now we have a few more
things to add to our checklist. For example, cylinders
must always be stored in the vertical position
with the valve end up, especially acetylene tanks. Next, cylinders should
never be transported in an enclosed vehicle. If a leak develops, there may
not be adequate ventilation, and leaking flammable gases
create an explosive atmosphere. We know that oxygen by
itself doesn't burn, but as we've seen, oxygen does
lower kindling temperatures and accelerates combustion, and of course high purity
oxygen will not only support but also amplify combustion. So when you're not using them, be sure to store flammable cylinders at least 20 feet away
from oxygen cylinders, or even better, separate them by a
properly-designed firewall. When you're actually
operating oxy-fuel equipment, we know that danger is always present as well as the potential
for a disastrous accident, so let's cover some of the safety issues that you should keep in mind
whenever you use gas cylinders. During operation, always be sure to keep sparks from coming in contact with a fuel gas cylinder. If a leak is present
somewhere in the system, of course this can cause a fire. For example, it's possible for the cylinder valve packing to leak and that means a fire is
just waiting to happen. It's also important never to
strike an arc on any cylinder with any arc-welding device. This can cause a weak spot in the cylinder or worse cause nearby
flammable gases to explode. Remember, all fuel gases
represent a flammable hazard. Acetylene for example is the most unstable of the fuel gases. It should never be used at pressures above 15
pounds per square inch. If acetylene is compressed
outside the cylinder at pressures greater than 15
psi, the gas becomes unstable and may result in what is known
as a dissociative explosion, and we definitely want to avoid that. To explain this a little
further let's talk about how an acetylene cylinder is constructed. First of all the cylinder itself is filled with a porous absorbent material which is then saturated
with liquid acetone. These components help keep
the gas stable under pressure in the cylinder. Here's a simple demonstration. This plastic bottle is
filled with colored water. You can see that the air creates a barrier between the water and
the neck of the bottle. Well, if the acetylene
cylinder is laid on its side, the acetone liquid can
fill the valve area, and then may be released into
the regulator when it's used. Remember that acetone
can damage the equipment and starve the flame which in turn may cause
the tip to overheat. If that happens, the result could be what's called a flashback. A flashback can be a
very dangerous situation and we'll be discussing that more completely a little later on. So remember, if it all possible, never lay an acetylene
cylinder on its side. Always keep it in an upright position. If you do find that it's
absolutely necessary though to lay an acetylene cylinder on its side, you should then allow that cylinder to stand in the upright position for at least twice as long
as it was on its side. Next, let's talk about oxygen. By itself we know that
oxygen is not flammable. It is, however, an oxidizer with pressures that can exceed 2,200 psi
in a fully-charged cylinder. And here's something
that may surprise you. Contrary to popular belief, high pressure oxygen, not fuel gas, is responsible for a
majority of the accidents that occur with oxy-fuel equipment. Therefore, it's important to remember, never completely empty the
entire contents of the cylinder. Instead be sure to leave a minimum of 20 psi in the cylinder. This will help prevent
the possible reverse flow of the opposite gas into that cylinder. And be sure that no oils,
grease or lubricants are allowed to come in contact with the oxygen cylinder or valve. We'll go into greater detail
on that a little later as well. Now our next section deals
with the proper inspection, setup and testing of oxy-fuel equipment. The first step in the correct
setup of an oxy-fuel system is to inspect the
cylinder valves for damage as well as for the presence
of oils and grease, especially on the oxygen
cylinder connections. Next, make sure that the
cylinders are properly secured. Visually inspect the
regulator connections, hoses and torch. Also inspect for nicks
or damage to O-rings and other seating surfaces, and be sure that safety devices
such as flashback arrestors or reverse flow check valves
are installed in the system. Look around to make sure
the area is well ventilated. Next crack the oxygen cylinder valve to blow out any loose dust or debris, but never direct that
oxygen stream toward anyone. After all, that debris could
be shot out in the stream and injure someone nearby. If dust or oil is present
in the oxygen connection, this too could be very dangerous. That's because the heat that's created by recompressing
high purity oxygen in the regulator will cause
the dust or oil to burn and that can result in a
regulator burnout or explosion. So always remember to crack
the oxygen cylinder valve to make sure it's clean. Next, we're going to go over some basic setup and testing procedures. First, let's attach and
tighten the regulator to an acetylene tank. When you attach regulators, be sure to position
them at an upward angle. In the unlikely event the adjusting screw were to blow out of the bonnet, then it would be projected up
and away from the cylinder. It's important to remember that every type of cylinder gas requires a
specific thread or connection. Do not attempt to use
regulators designed for one gas on another type of gas cylinder. Notice that the groove on the fuel gas connections
indicates a left hand thread. If acetylene is the chosen fuel gas, be sure that the delivery pressure gauge shows a red line at 15 psi. Before attaching the acetylene regulator, make certain that the cylinder
valve connection is clean and free of debris. There are four types of
acetylene cylinder connections. One of them uses a left-handed connection and the other three use
right-handed connections. Larger cylinders containing
over 40 cubic feet of gas are designated by the
Compressed Gas Association as having 510 and 300 connections. Here you can see a 510. If you look close you can see the groove that indicates this uses
a left-handed thread. And here is a CGA 300. Since there's no groove, this
is a right-handed thread. If you are using smaller
acetylene cylinders such as B or MC, the connections are different. These both are designed
with right hand threads. B tanks require a CGA
520 regulator connection and MC tanks require a CGA
200 regulator connection. Our next step is to attach the hoses, but before you do that make sure to visually inspect the
hose for any damage. Of course any worn or damaged
hoses need to be replaced. Next, make sure that you're
using the correct hose for your application. Special T-grade hoses should be used if gases other than acetylene are used. Well, once you've attached
the hoses to the regulators, make certain that the
torch valves are closed, then be sure to check the
regulator adjusting screws to ensure that they're in
the out and off position. Now let's pressurize the system. It's very important to open the oxygen cylinder valve slowly, allowing the regulator
to pressurize gradually. For safety's sake, always stand with the cylinder between
you and the regulator. If a regulator explosion occurs, it can explode in any direction, but the least likely direction
is toward the inlet pressure. Then continue opening the oxygen cylinder until the valve is fully open. The oxygen cylinder valve
should always be turned to the fully open or
fully closed position. Never leave it part way. Since all oxygen cylinders are designed with double seating valves, opening one all the way will prevent any cylinder valve leaks with a high pressure oxygen. This will also ensure an
unobstructed flow of the gas. Next, turn in the adjusting
screw on the regulator to approximately 10
pounds per square inch. Now, open the acetylene cylinder but only open it about
three quarters of a turn. This will allow a sufficient
gas flow for large tips but at the same time the cylinder can be quickly and easily shut off in case there's a fire. If the cylinder requires the
use of a key or wrench to open, be sure to keep the tool with the cylinder so that it can be shut down
quickly in the event of a fire. If you're using an alternate
fuel such as propane, it is necessary to open the
valve at least a few turns. Now turn the fuel gas
regulator adjusting screw in to 10 pounds per square
inch delivery pressure. Leak test all connections by using an approved
leak detection solution or oil-free soap and water. If bubbles appear, a leak is indicated. Another method of leak detection after pressurizing the system is to shut down both
cylinder valves completely with torch valves also closed, then on both regulators watch the delivery
pressure gauges over time. Be sure that there is no
pressure drop in the system which would indicate a leak. If a leak is detected,
first identify the location and then tighten the leaking
connection if possible, but if it's not possible to stop the leak, then the equipment should be taken out of service
immediately and repaired. Once you've determined that
the system is leak free, set the regulator adjusting screws to the appropriate
working outlet pressures with the tip being used. And here's a safety tip for you. Every time before you light the torch, it's important to purge
any gas from the hoses. This will eliminate the danger of having mixed gases in the system. To purge the torch, open the fuel valve and let fuel run through the
system for a few seconds. Be sure to close the
fuel valve on the torch and then repeat the same procedure for the oxygen side of the system. Once you've completed purging the torch, the system is now safe and ready to light. So let's move on to the next section of our safety presentation,
and that is lighting the torch. If you're using a combination style torch with a cutting attachment, be sure to open the valve on
the torch handle completely. That way you won't restrict oxygen flow for the cutting process. Now we'll open the fuel valve on the torch about one eighth to one quarter of a turn to allow a low volume stream of fuel gas to flow out of the torch tip. Using a friction style
striker ignite the fuel gas. To set the acetylene flame, open the torch valve until
there is no longer any soot being discharged from the outer flame. Once the soot discharge
from the flame disappears, or the flame just begins
to jump away from the tip, this is the minimum requirement
for acetylene gas flow. On the other hand, if
a large amount of soot is allowed to discharge from the flame it will cause a gas starvation situation and that will result in
the torch tip overheating. Now, let's slowly open the
torch oxygen preheat valve. Watch for what's known
as the secondary flame or acetylene feather to shorten or recede until
it's even with the primary or luminous cone as you can see here. This is what's called a neutral flame. Now that we've achieved a neutral flame let's cover some of the basics
dealing with flame settings. There are actually three
basic flame settings. Let's begin with the neutral flame. By definition a neutral flame has the proper ratio
of oxygen and fuel gas for both to be consumed
in the combustion process with a given tip design. By adding excess oxygen we
can create an oxidizing flame. Note how the primary
flames become very sharp and you can hear a loud hissing noise. And by supplying the
flame with excess fuel, or too little oxygen, we achieve what is known as a
carburizing or reducing flame. Alternate fuels on the other hand such as propane-based
fuels require several steps to achieve a neutral flame. So let's take a moment
to go through the process for setting a neutral flame
with alternate fuel gas. To set a neutral flame
with this oxy-propane tip, first ignite the propane and add oxygen. Don't forget that with LP gas
you have to force the fuel gas through the tip for maximum efficiency and to prevent starvation. Starving it will cause it to overheat. Now we'll work up the flame
by adding more fuel and oxygen until we have the fuel
gas near or at full flow. Once you have the proper fuel flow by working up the flame as we see here, add oxygen until the primary cones just reach their shortest point. We now have a neutral flame
with LP gas and oxygen. This process may be
utilized with natural gas, MAPP, propane or
propylene-based fuels as well. Remember, when working
with alternate fuel, it's important to maximize the fuel flow. One way to check to see if you have a neutral
flame with a cutting tip is to place the flame close and perpendicular to a metal surface. When you do that, you can see that the preheat flames will create a star pattern. The length of the legs of the star should be approximately two
and a half to three inches long with a fairly sharp definition. If the flame is oxidizing, the star pattern will look
short and very sharp like this. If the flame is carburizing, the star pattern will look
long and bushy like this. Oxy-fuel systems include the use of cutting, brazing,
welding or heating tips, and each tip style is designed
to perform a specific task. Each tip style and size also
requires a specific amount of gas pressure and flow
to operate correctly. Most equipment manufacturers recommend optimum pressure
settings for each tip design. So be sure to keep
operational instructions and technical information
like this tip chart, or manual, handy to identify
the correct pressure settings. In order for tips to perform correctly
during extended operations, specific pressures are required. Every tip requires a certain pressure and volume of gas flow, and while it is possible
to operate the tip with an insufficient gas flow, the tip will probably overheat and the heat buildup in that tip can eventually cause the gas to ignite before it has a chance to exit the tip. If that happens, we have a another dangerous
situation developing. This condition is known as gas starvation which can result in a backfire, sustained backfire or flashback. You can recognize a backfire by the loud popping sound it makes, and if it's allowed to continue, a backfire can lead to a flashback, and obviously we want to avoid
that situation at all costs. When gas pressures are correctly
set to the tip being used, the tip itself will remain cool during the duration of the operation with the exception of
residual or reflected heat from the work piece itself. Improper gas pressure settings
or insufficient gas flow can cause the tip to overheat. This again is known as tip starvation, and once that starved tip overheats, it will eventually cause the gases to ignite before they can leave the tip. This is called a sustained backfire which is characterized by a hissing sound with no visible flame
exiting from the torch tip and can lead to a flashback. Let's watch a demonstration and see what a sustained
backfire looks and sounds like. This particular torch is
designed with three tubes that keep the gases separated. Gas mixing takes place
only in the tip itself and therefore a sustained backfire is isolated to the tip only. Here we are forcing a sustained backfire. Watch closely and you will see the tip slowly begin to turn red. If you should experience a
sustained backfire or flashback, it's important to immediately turn the oxygen torch valve off first, followed then by turning
off the fuel gas valve. Remember, when you have a flashback, the flame is actually burning completely inside the torch and tip, and a flashback will always
burn backwards in the torch to wherever the gases are mixed, and this situation can occur
with any oxy-fuel torch, any torch tip style. Since we just mentioned how to shut down in case of a flashback, let's discuss the proper procedure for equipment shut down
during most normal situations. To correctly shut down a
Smith Equipment brand torch, you extinguish the flame by first turning off the fuel valve and then the oxygen valve. Other manufacturers though may recommend shutting
the oxygen off first, so it's always best to
find out what's suggested for the equipment you are using. After extinguishing the torch, the next step is to shut
down the gas source. So let's go ahead and
shut down our cylinders. Next we need to bleed the
gases from the system. You drain the oxygen by
opening the torch valve. Watch until both needles on the oxygen regulator
gauges drop to zero and then be sure to close
the torch oxygen valve. Next, back out the oxygen
regulator adjusting screw to the out and off position. Then repeat the process for the
fuel gas side of the system. Once that is complete, the gases will then be properly
evacuated from the system. Now let's talk about cylinder
withdrawal limitations. If acetylene is your fuel
gas of choice, it's important to understand cylinder
withdrawal capabilities. An acetylene cylinder can
deliver a maximum one seventh of its volume capacity per hour. Here's an example of how to calculate the
minimum size cylinder that is necessary to
support the tip being used. Let's say you're using a heating tip that requires 50 cubic feet
of acetylene gas per hour. You would simply multiply 50 times seven to find the total of 350 cubic feet. That represents the minimum
cylinder size needed to support the chosen tip
with the necessary gas volume. In some cases larger tips may require manifolding cylinders together to support them with the proper gas flow. In addition to acetylene, there are other fuel gas choices. The five gases most widely used in the welding industry include acetylene, MAPP, propylene, propane and natural gas. Each has advantages and
disadvantages depending on the specific application. Each gas choice also varies regarding its mixing ratio with oxygen, temperature of the neutral flame, heat output measured by
BTUs and burning rate. Fuel gases other than acetylene are commonly referred
to as alternate fuels. Alternate fuels can also have cylinder withdrawal limitations but some of the hazards
associated with acetylene do not exist with alternate fuels. Again, refer to the
manufacturer's recommendations for gas supply relative to the tip choice. At this point I'd like to
mention a couple of things that I think are very important. First, be sure you never use
matches or a cigarette lighter to ignite the torch. Doing so could cause you
to severely burn your hand. And also if the flame comes in contact with the lighter itself, that flame could quickly burn through and cause the lighter to explode. Second, be sure to keep matches, lighters or other combustible
materials out of your pocket while operating an oxy-fuel torch. Any of these things
could accidentally ignite and set your clothing on fire — and we want to avoid that at all costs. There are three styles
of oxy-fuel torches, hand torches which are
designed basically for cutting, machine torches, designed
for automated processes, and combination torches which are designed for use
with a variety of tip styles. As you can see a
combination torch is capable of using a cutting assembly, a heating tip or a welding tip. Here's another safety note. Don't forget what we talked about earlier, that any of these torch designs
is capable of a flashback. And while torches are
designed with various options, two basic operational problems can occur, no matter which torch brand or style. Reverse of gas in the
torch and fire in the torch are two conditions which
must always be avoided. These conditions can be caused by improper pressure or flow settings. They can also be caused by
incorrect torch ignition or improper operational techniques such is dipping the
tip into molten metals, dirt in the system or allowing cylinder contents
to be completely depleted. Many accidental fires
are started each year by sparks produced by oxy-fuel operation. Always remember that sparks
can fly up to 50 feet from a cutting torch and
possibly start a fire that you can't even see
until it's too late. So it is very important to
carefully check the work area for combustible materials
before operating any torch but especially a cutting torch. A reverse flow of gas may occur when one side of the oxy-fuel
system is void of pressure. Unfortunately cutting
torch operators often try to use up every last bit
of oxygen in the cylinder. As the cylinder empties, the operator usually will
open the torch oxygen valve even further to compensate
for the loss of pressure. Of course the same thing can happen if you use up all the fuel gas. This is especially a
problem with a cutting torch since the oxygen pressure
is usually much greater than the fuel gas pressure. This can be a dangerous situation because the higher of
the two gas pressures will reverse flow to the
path of least resistance. This condition allows
gases to mix in the system, creating a very dangerous situation. We have now established
two of the elements of our fire triangle that
we discussed earlier, and once again this means that purging the system
before igniting the torch is very important in order to rid the
system of any mixed gases. Reverse flow check valves
are one-way flow devices that can be installed to prevent the reverse
flow of gas from occurring. It should be noted however that check valves do not
stop flashback fires. These check valves can
be mounted on the torch or the regulator. Check valves must be tested
or replaced periodically to ensure that they are
sealing up properly. If debris is present in the system, the device may not close
and seal as it should. This is an important so I want
to mention it one more time. While check valves are
excellent safety devices, they will not stop a flashback fire. Next, let's talk about something that can help to stop a flashback fire, an excellent safety device
known as a flashback arrestor. Here is a typical flashback arrestor. It can prevent fire from migrating backward
in the torch system from the point at which it's installed. Also, flashback arrestors
come in either torch-mounted or regulator-mounted designs. It isn't necessary though
to use flashback arrestors or check valves with
air-fuel style torches. Flashback arrestors have a
stainless steel filter in them to break up a flashback fire. Most flashback arrestors also
have a check valve built in for added safety to prevent
the reverse flow of gases. It's important to note that
flashback arrestors can and will create some
gas flow restrictions, and when you're using cutting tips or large heating tips such as this, it may be necessary to
increase the gas pressure to compensate for the reduced flow. So be sure to check the
manufacturer's recommendation for gas flow capacity. Also over time dirt or soot
can accumulate in these devices causing further gas flow restrictions, therefore flashback arrestors need to be changed periodically, especially in severe
or dirty applications. Regulator burnout is
another potential hazard with oxy-fuel equipment. Regulator burnouts damage equipment and can cause serious
injury or even death. There are four main types
of regulator burnout, dust oxygen, oil oxygen,
dissociative gas and mixed gas. A dust oxygen regulator explosion can occur in the oxygen regulator if dust or other fine particulate
is in the cylinder valve when the cylinder is opened very rapidly. Oxygen can build up heat while it's escaping from the cylinder and recompressing into the regulator. This is known as the
heat of recompression. It may seem hard to believe but for a brief moment of
time temperatures can rise as high as 1,700 degrees Fahrenheit. Concentrations of dust, oils or grease will burn or explode in the regulator under these conditions. And remember, the kindling
temperature of steel is only 2,200 Fahrenheit, so for safety's sake always be sure that the cylinder valve
and regulator are clean. And as I mentioned earlier,
before attaching the regulator, be sure to crack the oxygen valve to blow out any debris
that may be present. The next cause of regulator
burnout I want to discuss is caused by oil and oxygen. An explosion occurs in an oxygen regulator when pressurized high purity
oxygen comes in contact with oil or petroleum-based chemicals, and one reason this is so dangerous is because the kindling
temperature can be achieved by simply opening the oxygen
cylinder valve too rapidly. Caution is always necessary. Remember that high purity oxygen lowers the kindling temperature and that accelerates
the combustion of fuels. So never use an oxygen cylinder that has oil or grease in the valve. And here are some other good never tips. Never use an oxygen regulator on anything other than an oxygen cylinder, never use oxygen as a substitute for air, and never use oxygen for
dusting off clothing, running pneumatic
equipment or filling tires. Remember how quickly the steel wool burned when high purity oxygen was introduced into the combustion process? So, therefore, oxygen should only be used for what it's intended. The third type of regulator burnout I want to briefly discuss is
caused by dissociative gas. A dissociative explosion
occurs when acetylene is used at pressures greater than 15 psi, and we talked about that earlier. Actually, what happens in
a dissociative explosion is that the acetylene molecules separate, creating heat energy — and
that results in combustion. And the final type of
regulator burnout on our list is mixed gas burnout. A mixed gas burnout occurs when oxygen and fuel are
mixed within the system and then are ignited. This can occur anywhere in the system. So once again, to avoid
a mixed gas explosion it's important that you
never allow cylinders to be emptied completely, and always purge each line separately before igniting the torch. Also, be sure to use proper start up and shutdown procedures, and of course never use
damaged or worn equipment. Now, as we near the end
of this presentation, I want to go over our safety checklist. Before using an oxy-fuel
system it's always wise to perform a brief visual
equipment inspection. Many hazards can be eliminated
by simply being aware of what condition the equipment is in. The safe operation of gas apparatus also includes proper personal protection. We know that there is
always danger present when you're using an oxy-fuel system. Oxy-fuel torches are capable of producing a 6,000
degree Fahrenheit flame, molten metal, ultraviolet rays, and they can shoot sparks over 50 feet, therefore it is absolutely necessary to use the right protective gear. And the right gear
covers a number of items. Your eyes require protection
from the oxy-fuel flame. The minimum correct lens shade level for cutting steel is shade five. While shade three is acceptable for brazing and soldering operations, but don't forget your eyes can be damaged if you don't use shaded eyewear. Another good idea when
you're working with torches is to wear fire-resistant clothing such as long-sleeve shirts, heavy gloves and protective leather boots. Avoid wearing synthetic
fabric when operating a torch as well as cuffed pants or loose pockets that slagger molten metal could fall into, and be sure not to
carry lighters, matches or other combustibles in your pockets. And finally, before you
begin any torch application, always take a moment
to simply look around. Check out the area you're about to work in to make sure that it's
free of all combustibles, and always keep an approved
working fire extinguisher on hand in case of a fire. It's also important to
never cut, weld or braze on closed containers that may
have held combustible material such as gas, oil or other
potentially explosive chemicals. Now, before we end our presentation, I'd like to recap the
principles of oxy-fuel safety that we've been discussing
throughout this presentation. It is important to use quality equipment that is of good repair. Always make sure the
equipment is set up properly and is free of leaks. Wear the right protective gear. Be sure to cap unsecured
compressed gas cylinders. Take advantage of safety devices such as check valves, hard
hats and flashback arrestors. Always maintain a safe and
clean work environment. Be sure to keep an approved and working fire extinguisher handy. Always follow the proper
operational procedures designated for the type of equipment you are using. Make sure the regulator adjusting screws are in the off position before
opening the cylinder valve. Always purge the hoses
before igniting the torch. Never use acetylene at pressures greater than
15 pounds per square inch. Be sure to supply a sufficient
gas flow and pressure for the tip being used. Never use oxygen as a
substitute for compressed air. Never use oil on regulators,
torches, fittings or other equipment in contact with oxygen. Keep heat, flames and sparks away from combustible materials. Never transport cylinders
in an enclosed vehicle. And finally, do not attempt to alter or repair oxy-fuel equipment yourself. Additional
safety information on oxy-fuel and other
gas apparatus operations is available on www.MillerWelds.com. And one final thought. While it's taken some time to explain all of the safety precautions and procedures that we've discussed here, it really only takes a few
seconds to follow each of them, and doing so can eliminate
injuries or even save your life. Thanks for watching. This presentation has
covered the basic principles of the safe operation
of oxy-fuel equipment. Not all circumstances or
situations of torch operation may have been addressed, nor have subjects been
covered in complete detail, so please always refer to
your manufacturer's literature for safe operation, and be sure to contact the manufacturer if you have questions regarding
the use of any equipment.
