31. IGNITION CYLINDER.
_a. Description and functioning._ (Figs 13 and 22) Either the M1 or
E1 ignition cylinder may be used. It fits over the fore part of the
barrel assembly and is revolved by the spring case. (Par 76) The five
incendiary charges in the cylinder are spaced sufficiently far apart
in the plastic body to prevent their igniting one another. Lead-foil
seals, plastic closure plates, and waterproof cement make the unit
comparatively waterproof.
[Illustration: Fig 22. Cutaway view of ignition cylinder (M1 or E1).]
_b. Action._ When the trigger rod is pushed forward, one of five metal
matches tipped with red phosphorus scratches an igniting mixture. The
ignition carries to a starter mix and to a few grains of black powder
on top of the incendiary charge. The black powder blows the foil seal
and closure plate clear of the flame thrower, and the incendiary
charge ignites the fuel as it is discharged from the nozzle. The
incendiary charge burns for from 8 to 12 seconds.
_c. Packing._ Ignition cylinders are packed two per waterproof can.
Three cans are furnished with each flame thrower. Fifty cans (100
ignition cylinders) are contained in each packing box of extra
cylinders.
_d. Care, handling, and storage._ Ignition cylinders contain hazardous
incendiary material and must be handled with due care. The following
precautions should be observed.
(1) _Opening cans._ Do not open cans containing cylinders until ready
to load for a mission. (Par 18) If an extra cylinder remains in an
opened can, use it as soon as possible. Any defective cylinders, such
as those with damaged closure plates, should be destroyed. (Pars 30 and
46) Moisture may affect the cylinders and all possible care should be
taken to avoid exposing them to dampness.
(2) _Handling cylinders._ Pressure on any of the five metal matches
(Fig 13) may ignite an incendiary charge in the cylinder. Care must
be exercised to avoid putting pressure on the projecting ends of the
matches except when firing the weapon. Ignition cylinders and cylinder
containers should be protected against shock. Boxes and cans containing
cylinders must not be thrown or dropped.
(3) _Storing containers._ Containers of ignition cylinders are best
stored in a dry, well-ventilated place, out of the direct rays of the
sun, well protected against excessive temperatures. Smoking is not
permitted and matches are not used where ignition cylinders are stored.
32. CHARGING PRESSURE TANK.
_a. General._ The pressure tank of the flame thrower must be fully
charged with compressed air or compressed nitrogen before the start of
a mission. For the M2-2 flame thrower, a pressure of at least 1,700
pounds per square inch is required. This may be provided either by the
use of an air compressor capable of producing a pressure of at least
1,700 pounds per square inch, or by the use of commercial cylinders.
The filling and charging lines from the service kit are used in
conjunction with the cylinders. Before and after charging, follow the
procedures described in Paragraphs 51 and 55.
_b. Charging from air compressor._ Compressor, air, gasoline engine
driven, 7CFM, M1, is a self-contained, skid-mounted machine designed
for use with flame throwers. It is capable of charging pressure tanks
of flame throwers and large 200- or 220-cubic-foot commercial cylinders
as well. Instructions for use of the compressor will be found in the
manual accompanying it.
_c. Charging from cylinders._ If an air compressor is not available,
it is necessary to use cylinders containing nitrogen or air.
(1) _Volume and pressure._ Cylinders come charged with 200 to 220 cubic
feet of air or nitrogen. Since cylinders with 220 cubic feet of air or
nitrogen have a higher initial pressure, it is recommended that they
be procured, if obtainable. All cylinders used must have a pressure of
at least 600 pounds per square inch. One or more of the cylinders must
have a pressure of at least 1,800 pounds per square inch. Two or more
cylinders, preferably at least four, should be used, if available.
(2) _Charging capacity._ Fully charged cylinders, if properly used in
rotation, have capacity for charging pressure tanks approximately as
follows:
1 cylinder (used alone) 2 pressure tanks
2 cylinders (in combination) 6 pressure tanks
4 cylinders (in combination) 24 pressure tanks
5 cylinders (in combination) 36 pressure tanks
6 cylinders (in combination) 48 pressure tanks
(3) _Apparatus._ The apparatus for charging two pressure tanks by
the use of cylinders consists of a filling line, two charging lines,
and two cylinders. (Fig 23) The filling line and charging lines are
obtained from the service kit. (Par 48) Plugs are provided to close off
either half of the filling line when only one flame-thrower tank group
is to be charged.
(4) _Warning._ Oxygen is sometimes shipped in cylinders having the same
threads as nitrogen cylinders. If oxygen not mixed with nitrogen, as in
air, is introduced into the fuel tanks of the portable flame thrower,
a violent explosion may result. Therefore, the greatest care must be
exercised to see that only air or nitrogen is used. _Before a cylinder
is connected, it should be tested to determine that it does not
contain straight oxygen or some combustible gas._ This may be done by
introducing a burning splint into a jet of the contents. Oxygen causes
the splint to burn quickly, whereas nitrogen extinguishes the flame. To
make the test:
(_a_) Fasten a thin splint of wood to a wire at least a foot long.
(_b_) Ignite the splint.
(_c_) Stand aside and hold it before the cylinder outlet.
(_d_) Crack the valve slightly to permit a small stream of gas to
emerge.
(_e_) If the flame flares up, the gas is oxygen and _MUST NOT_ be used.
(_f_) If the gas itself catches fire, it may be hydrogen, acetylene, or
some other combustible gas, which also must not be used.
(5) _Attaching lines to cylinders._ (Fig 23) The procedure for charging
two flame thrower pressure tanks from two cylinders of nitrogen or
compressed air begins as follows:
(_a_) Remove the valve-protection caps from the cylinders.
[Illustration: Fig 23. Charging two pressure tanks, using charging and
filling lines, and cylinders of compressed air or nitrogen.]
(_b_) Place the cylinders side by side with both outlets facing in the
same direction. (If the ground is not level enough for the cylinders to
stand up side by side, lay them horizontally with both outlets face up.)
(_c_) Before attaching the filling line to the cylinders, blow out
dust. (Par 33) Then connect, using wrenches to make the joints pressure
tight. Do not kink or bend the flexible hose. Cylinders must be close
enough together to prevent strain on the flexible hose.
(_d_) Attach a charging line to each of the two couplings on the
filling line.
(6) _Attaching charging lines to pressure tanks._
(_a_) Close pressure-tank valves.
(_b_) Unscrew caps from check valves.
(_c_) Screw the charging-line fittings onto the check valves.
(_d_) Close bleeders.
(7) _Charging._ The operation of charging two pressure tanks from two
cylinders is as follows:
(_a_) Close both filling-line valves.
(_b_) Open cylinder valves.
(_c_) Determine which cylinder has the lower pressure by the gages.
Open the filling-line valve at the gage showing the lower pressure and
fill the pressure tanks to the pressure shown by the gage. Close the
valve. Then open the other filling-line valve and fill the pressure
tanks until they reach pressures of at least 1,700 pounds per square
inch as shown by the gage.
(_d_) When the pressure tanks have been filled, close the filling-line
valves. Open the bleeders on the charging lines and leave them open
until the pressure in the charging lines is released. Then close
bleeders. Remove the charging-line fittings from the check valves.
Screw the threaded caps on the check valves and tighten caps with a
wrench.
(_e_) Repeat steps in (_a_) through (_d_) above for as many pairs of
empty flame-thrower tanks as require charging.
(8) _To insure proper pressure._ Care should be taken to make certain
that the compression delivered to the flame-thrower pressure tank is a
full 1,700 pounds per square inch.
(_a_) If a filling-line valve leaks, tighten the packing nut on the
valve with a wrench.
(_b_) When the higher pressure shown on the filling-line gages is less
than 1,700 pounds per square inch, close the filling-line valve and the
cylinder valve on the cylinder having the lower pressure. Remove and
replace this cylinder with a fully charged cylinder. With chalk, mark
the pressure on the cylinder which has been withdrawn.
(9) _After charging._ When charging has been completed:
(_a_) Close the filling-line valves. Observe the pressure indicated on
each gage and mark the pressure on each cylinder using crayon, chalk,
or pencil.
(_b_) Close the valves on the cylinders.
(_c_) Remove the charging-line fittings from the check valves, replace
the threaded caps on the check valves, and tighten caps with a wrench.
(_d_) Remove the filling lines from the cylinders. Use two wrenches and
take care not to twist or kink the flexible hose. Support the lines
during the operation so that their full weight does not hang on the
flexible hose during removal.
[Illustration: Fig 24. Arrangement of cylinders and lines for charging
four flame throwers. Flexible hose (assembly E81-3-6) from service kit
is used to connect two filling lines.]
(10) _Use of four-place lines._ (Fig 24) The filling and charging lines
found in two or more service kits may be combined for more efficient
charging of large numbers of pressure tanks. An additional flexible
hose is provided in each service kit for connecting two filling lines.
The procedure for charging is similar to that described above for
the two-place line. Air or nitrogen is taken first from the cylinder
with the lowest pressure and last from the cylinder with the highest
pressure. See _a_ (2) above.
33. PRECAUTIONS WHEN PRESSURE-CHARGING.
Personnel will familiarize themselves with the following precautions:
_a. Handling._ Handle all cylinders and flame throwers carefully;
never drop them and never subject them to shocks or blows. Keep
valve-protection caps secured when cylinders are being handled, except
when such handling is incident to the use of the nitrogen or air.
_b. Storage._ Keep all cylinders and charged flame throwers or tank
groups (Par 77) in open or closed storage. They must, however, be
protected from dampness and excessive rise in temperature caused by the
direct rays of the sun or other source of heat. Avoid storing them near
highly flammable substances, or in places where they may be struck by
moving objects. Segregate empty cylinders to avoid confusion.
_c. Personnel._ Do not attempt to use compressed gases unless trained
in this work. Use gases only for the purposes for which they are
intended.
_d. Cylinder valves._ Do not tamper with safety devices in cylinder
valves. If available, use the proper replacement parts for safety
devices which are in need of repair. If such parts are not available,
do not attempt to use makeshifts or nonstandard parts.
_e. Opening of valves._ Open valves slowly and fully each time nitrogen
or compressed air is transferred from a cylinder. When a wrench is
used, be sure it is one that fits properly, and that it is kept ready
for instant use while the compressed gas is being released.
_f. Threads._ See that threads match before making connections. Some
valves are provided with special threads which must be matched by the
threads in the equipment being connected.
_g. Correct equipment._ Use gages, regulators, hose, pipe, and tubing
of the type manufactured or specified for the particular apparatus or
compressed gas.
_h. Repair._ Never attempt to alter or repair a cylinder.
_i. Flames and sparks._ Do not permit flames, sparks, or ignition from
the flame thrower or other source to touch hose.
_j. Blowing out dust._ Immediately before coupling an attachment to the
pressure tank or cylinder valve, open it for an instant to blow out any
dust or dirt. Never stand where gas or dirt may be blown into the eyes
or face. If the valve is difficult to open, apply more force gradually.
_k. Special devices._ Do not attempt to use any special connections or
equipment without the approval of a qualified expert.
_l. Keeping valves closed._ Keep the valve of each cylinder closed when
its contents are not actually being released from or admitted to the
cylinder. This applies alike to all cylinders, whether they contain a
compressed gas or are empty.
34. CHARACTERISTICS OF FUELS.
Thickened fuels give up to twice the range of liquid fuels. The stream
of thickened fuel is comparatively narrow. Most of the glue-like fuel
clings to and burns in or on the target for as long as 6 minutes.
Liquid fuels, on the other hand, are largely consumed in flight to the
target. If the location of small openings in the target is known, the
stream of thickened fuel can be spotted by accurate aiming so that
most of the fuel enters directly into the openings. While it does not
billow around corners as does liquid fuel, thickened fuel strikes the
target with force enough to ricochet inside. It clings to skin and
clothing while burning. It also has excellent incendiary effects. The
initial flame and smoke are less from thickened fuel than from liquid
fuel, but the lower visibility, greater range, and much longer burning
period of thickened fuel compensate for its smaller screening effect.
Liquid fuels are easier to pour when filling than are thickened fuels.
35. PREPARATION OF THICKENED FUELS.
_a. Ingredients._ Thickened fuels consist of U.S. Army fuel thickener
mixed with fuel.
(1) _Thickener._ U.S. Army thickener is supplied in airtight cans, each
containing 5-1/4 pounds of the material.
(2) _Gasoline and fuel oil._ Gasoline alone is often used with
thickener, but mixtures of gasoline and light fuel oil may be used
satisfactorily. The light fuel oil can be either No. 1 fuel oil, No.
2 fuel oil, automotive diesel oil, or kerosene. These mixtures give
more heat and do not form crusts. Except in hot climates, 75 percent
or more of the mixture by weight or volume should be gasoline. (If too
much light fuel oil is included, the fuel tends to separate into two
layers.) In tropical theaters, a thickened blend of 50 percent gasoline
and 50 percent light fuel oil has been reported to give favorable
results. Storage qualities are not known, however. Another mixture
which has been well recommended in field reports is 15 gallons of
gasoline to 5 gallons of diesel fuel oil. Issue gasoline may be used,
but locally procured gasolines which contain alcohol are not suitable.
_b. Proportion of thickener to fuel._ Less thickener is recommended
than formerly. A low ratio of thickener gives a thickened fuel with
many of the characteristics of liquid fuel. One can of thickener to 20
U.S. gallons of gasoline, or gasoline and light fuel-oil mixture, gives
good results. This is a 4.2 percent by weight mixture. Except in hot
weather, a fuel mixture of less than 3 percent thickener requires such
long stirring that its preparation is impractical.
_c. Equipment._ An open-head 55-gallon or 42-gallon drum and an
improvised wooden mixing paddle are used. Five-gallon cans may
be employed to transfer the ingredients. The paddle should be
approximately 5 feet long, 2 inches wide, and 1 inch thick. If a
standard 55-gallon, open-head drum with an internal diameter of 27-7/16
inches is used, the improvised paddle should be marked to indicate
gallons as follows:
_Gallons_ _Inches_
40 23-1/2
20 11-3/4
Do not use a metal paddle because of the danger of striking a spark
from the drum. Never use galvanized containers for mixing and storing
thickened fuels. These may cause the fuel to break down and become
excessively thin. An improvised funnel may be helpful in filling drums
with prepared fuel for aging or transporting.
_d. Temperatures._
(1) _Below 50 degrees._ If the temperature is below 50 degrees
Fahrenheit, it is helpful to prepare thickened fuel indoors, in a
heated room. All precautions should be particularly observed. (Par 40)
(2) _Above 90 degrees._ When the fuel is hotter than 90 degrees
Fahrenheit, the thickener reacts very rapidly. In this case, it is
easier to prepare batches of 20 gallons each, but any number of batches
may be prepared in succession.
_e. Moisture._
(1) _Effect of moisture._ Water in thickened fuel breaks down or
reduces the viscosity of the gel and thereby reduces the range of the
flame thrower. This effect may not be noticeable at once, but the
stability of the fuel is affected.
(2) _Dryness of thickener._ Dry thickener is extremely hygroscopic,
that is, it absorbs moisture from the atmosphere very rapidly. For this
reason, thickener is shipped in hermetically sealed tin cans containing
the exact quantity of powder required for mixing with 20 gallons
of fuel to prepare a 4.2 percent mixture. It is important that the
gasoline or fuel oil and gasoline be measured out before the thickener
container is opened. The powder then should be poured immediately into
the liquid.
(3) _Dryness of containers._ It is important that all containers used
in mixing and handling the fuel be dry.
(4) _Keeping water out of gasoline._ Gasoline, especially when it has
been stored in vented containers, frequently includes free water.
Therefore, when using gasoline from a bulk-storage tank or an open
drum, first place it in a clean, dry drum; allow it to stand quietly
for at least an hour; then carefully pour off the gasoline from the top
and discard the last gallon or two.
_f. Pouring and stirring._ (Fig 25) The liquid fuel is poured into the
open drum; a pail or a paddle (Par 35 _c_) is used for measuring. One
man then stirs the fuel vigorously. Another takes a can of thickener,
splits it with a machete, bayonet, or ax, and pours it immediately
into the fuel. Any large lumps of powder are broken by hand before the
powder is added to the fuel. When mixing 40 gallons at a time, the
two cans of thickener should be opened and added to the fuel in rapid
succession. If the contents of the first can are permitted to gel
before adding the second can, it will be difficult to obtain a uniform
mix. Continue to stir.
[Illustration: Fig 25. Measuring fuel ingredient into mixing drum.
Paddle for measuring and stirring is improvised.]
[Illustration: Fig 26. Transferring newly mixed thickened fuel from
mixing drum to storage or shipping container for aging.]
_g. Examining fuel._ Lift the paddle quickly. If the mixture drops
or runs from the paddle, additional stirring is necessary. When the
paddle comes out clean, except for an adhering film, stirring should be
stopped, provided there is no further visible
settling of particles of thickener.
_h. Loading shipping drums._ When stirring is completed, the mix is
immediately bucketed (Fig 26) through a funnel into the shipping drum.
The second bung hole should be open, if possible, to provide a vent
to aid in pouring. Two men do the bucketing, each handling one pail
so that the funnel may be kept loaded with mix and the shipping drum
filled as rapidly as possible. Finally, the open-end drum should be
picked up and its contents poured into the funnel. Not more than 50
gallons of thickened fuel should be loaded into a 55-gallon drum. The
funnel should then be removed and replaced by a plug. The vent opening
of the drum should also be closed. (See Paragraph 39 for pressure
method of filling storage drums.)
_i. Unused thickener._ Any thickener remaining in opened cans should be
discarded. Since moisture in the air can quickly ruin its properties,
no attempt should be made to save it.
_j. Aging and storing._ Newly mixed fuel has the appearance of tapioca
pudding. (Fig 27) It should preferably be stored overnight before
use. It may, however, be fired within 1 hour after mixing. To keep
fuel in good condition, drums for shipping and storing must be clean,
moistureproof, dry, strong, and unrusted, but not galvanized. They must
be kept tightly closed and should be laid on their sides so that rain
water will not collect around the bungs.
_k. Testing fuel._ Before use on missions, all fuels should be tested
by being fired from a flame thrower. This is advisable because the
characteristics of the fuel ingredients often vary.
[Illustration: Fig 27. Contrasting newly mixed thickened fuel (right)
with aged fuel (left).]
36. PREPARATION OF LIQUID FUELS.
_a. Choice of ingredients._ Thin fuels are easy to ignite, but they
lack range and are largely burned in flight before reaching the target.
For this reason, liquid fuels should contain the lowest proportion
of gasoline and the highest proportion of heavier oils that permits
easy ignition. In hot climates, less gasoline is needed than in cold
climates. Exactness of proportion, however, is not of great importance.
Suitable blends are as follows:
(1) Equal parts by weight or by volume of gasoline, light fuel oil, and
heavy (bunker) fuel oil. The light fuel oil can be either No. 1 fuel
oil, No. 2 fuel oil, automotive diesel oil, or kerosene.
(2) One part gasoline to four parts of cleaned crankcase drainings.
(Par 36_e_) Unused motor lubricating oil can be employed in place
of crankcase drainings, but usually it will be unavailable for
flame-thrower use.
_b. Preparation of ingredients._ Before mixing blends, the following
steps should be taken:
(1) _Gasoline, diesel oils, and fuel oils._ These fuel materials should
be allowed to stand quietly for at least 30 minutes to permit any small
quantity of water present to settle to the bottom. When transferring
the fuel to another container, remove the fuel carefully so that no
water is remixed with it.
(2) _Crankcase drainings._ If possible, crankcase drainings should
be allowed to stand quietly in a container for at least 1 day. When
pouring, take care to prevent the transfer of any of the sludge which
may have settled in the bottom of the container.
_c. Equipment._ An open-head 55-gallon or 42-gallon drum and an
improvised wooden mixing paddle are used. The paddle should be
approximately 5 feet long, 2 inches wide, and 1 inch thick. A metal
paddle should not be provided because of the danger of striking a spark
from the drum. Five-gallon cans may also be furnished for measuring and
transferring ingredients. Clean, unrusted, steel storage drums should
be at hand. They should be at least 16-gage to have sufficient strength
to withstand the internal vapor pressure of the fuel.
_d. Stirring._ All the ingredients should be stirred in the drum with
the paddle until they appear to form a uniform mixture. This should
require approximately 2 minutes.
_e. Crankcase-draining blends._ If crankcase drainings are used as
an ingredient (Par 36_b_), it is preferable to allow the prepared
mixture to settle for 24 hours after stirring, because the gasoline in
the mixture may cause additional sludge to be deposited. Even after
this settling period, it is recommended that the mixture be poured
through cheesecloth or some similar fabric before the flame thrower
is filled. Crankcase-draining blends should be allowed to stay in the
flame thrower only long enough for completion of a mission, because
additional sludge which may form from standing will clog the weapon.
_f. Transferring._ The mixture should be transferred either directly
into the flame-thrower fuel tanks (Pars 37 through 40) or into storage
drums. (Par 35_h_)
_g. Emergency mixing in fuel tanks._ In an emergency, mixing can be
done in the flame-thrower fuel tanks by adding the ingredients in
correct proportions and then shaking or stirring.
_h. Testing fuel._ Before fuel is used on a mission, it should be
tested, if possible, by being fired from a flame thrower.
_i. Storage._ Fuels may be used immediately after preparation. If
the blend contains crankcase oils, the fuel should be fired as soon
as practicable after filling. Other liquid blends may be stored
indefinitely until required for use. For storage precautions see
Paragraph 40. The storage drums also should be kept tightly closed to
prevent loss of gasoline through evaporation and to prevent moisture
from entering the fuel. If stored in the open, the drums should be laid
on their sides so that rain water will not collect adjacent to the
bungs. An unrusted and undamaged 16-gage or 18-gage drum has sufficient
strength to withstand the internal vapor pressure of the fuel.
37. FILLING BY POURING.
[Illustration: Fig 28. Filling fuel tanks by pouring. Any clean
container may be used. A funnel may be improvised.]
(Fig 28) This method is the simplest and quickest for liquid fuel,
but it may be too slow for some thickened fuels. The procedure is as
follows:
_a._ Stand the tank group on the ground or a platform. If the tank
group is not connected to the gun group, lock coupling plug in tank
coupling. (Par 70)
_b._ Using a 1-3/4-inch wrench, unscrew the filling plug and the
safety-head plug.
_c._ Inspect interior of tanks to see if clean and free from foreign
matter. If not clean, flush with gasoline.
_d._ Using an improvised funnel, fill to within 2 inches of the top of
both plug openings. This allows sufficient void. The tanks will then
contain approximately 4 gallons of fuel.
_e._ Wipe the fuel-tank plug seats and the plug threads with a clean,
dry cloth. (Fig 29) If plug has a tendency to freeze to seat, lubricate
(Par 49 _b_) before screwing in the filling and safety-head plug
assemblies. Tighten with wrench.
[Illustration: Fig 29. Wiping plug seat.]
_f._ Wipe any spilled fuel from weapon.
38. FILLING BY FORCE PUMP.
A force pump, if available, may be installed with a short length of
pipe in the top opening of a drum of fuel for filling flame-thrower
fuel tanks. Keep working parts of pump clean.
39. FILLING BY BLOWING.
Thickened fuel may be readily forced into the fuel tanks of flame
throwers by the use of extremely low pressures of compressed air or
nitrogen. Flame thrower fuel filling kit E6 or equivalent may be used.
When equipment is available, filling by blowing is more efficient for
filling large numbers of flame throwers with thickened fuel. Pouring
or pumping are more time-consuming, depending on the consistency of
the gel. The consistency may vary among batches even when the same
proportion of thickener is used. The amount of moisture in the fuel
seems to cause this variation. The precautions listed in Paragraph 40
should be observed.
[Illustration: Fig 30. Blowing thickened fuel into fuel tanks by use of
cylinders of compressed air or nitrogen.]
_a. Source of pressure._ When the pressure in cylinders of compressed
air or nitrogen has fallen too low to be of further use in filling
pressure tanks of flame throwers, the remaining pressure may be used
to blow fuel into fuel tanks if the regulator valve can reduce pressure
down to 20 pounds per square inch. For precautions, see Paragraph 33.
An air compressor or a hand air pump (tire pump) may be used in place
of a cylinder if the latter is not available. Pressure of _no more than
15 to 20 pounds_ per square inch should be used on the fuel drums. Only
a diaphragm-type regulator valve can be used safely. This valve must be
capable of regulating any pressure that may be applied to it.
_b. Drums._ Clean, noncorroded, steel, 55-gallon drums should be used.
Drums of United States manufacture which meet requirements will be
stamped ICC-5 or ICC-5A, followed by three numbers in sequence, for
example, “14-55-44.” The number “14” indicates the gage of the metal;
“55” indicates the capacity in gallons; and “44” indicates the year
of manufacture. A steel drum of 14 gage, or heavier, is preferable,
but lighter drums (of 16 or 18 gage) may be used. Drums made of gages
lighter than 18 gage (20-or 22-gage) must not be used. Drums should
never be moved while under pressure.
_c. Connections._ The source of pressure (see _a_ above), the drum
of fuel, the fuel-filling line, the air hose, and other parts, are
connected as shown in Figure 30. Threaded adapters are used, as
necessary, to fit lines to the drum. All threaded connections should
be made tight by the use of wrenches on the joints. The drum and the
pressure cylinder (if the latter is used) should be laid on their sides
on the ground or a platform. The opening of the drum connected to the
fuel-filling hose should be close to the ground or platform. If tank
group is filled without gun group, lock coupling plug (Par 70) in tank
coupling.
_d. Procedure._ To fill fuel tanks:
(1) Remove both the filling and safety-head plugs.
(2) Inspect interior of tanks to see if clean and free from foreign
matter. If not clean, flush with gasoline.
(3) Place end of fuel-filling hose in either one of the two fuel-tank
plug holes, using a nipple as a spout.
(4) Start air compressor or pump, or open the valve on the cylinder of
compressed air or nitrogen. Open regulator valve on filling line by
turning handle _slowly_ until gage shows 15 to 20 pounds pressure, but
no more. _Caution_: “Cracking,” or opening a cylinder valve without
using the proper regulator valve (Par 39 _a_), may result in explosive
pressure in the drums.
(5) Both tanks must be filled to within 2 inches of their tops. Close
valve on fuel-filling hose to halt flow at this level.
(6) If no additional flame throwers are to be filled, close
pressure-cylinder valve, or stop compressor or pump. Then, using
wrench, slightly loosen the air line at the drum, allowing pressure
to bleed. When the pressure in the drum has fallen to that of the
atmosphere, close regulator valve.
(7) Roll drum slightly and gently until fuel-filling hose is at top of
drum.
(8) If there are valves on each end of the fuel-filling hose, use
wrench to slightly loosen hose, allowing gradual escape of pressure.
Stand away from, and at the side of, the connection. Keep hose pointed
away from other personnel. When all pressure has been released,
complete unscrewing of hose.
(9) Wipe fuel-tank plug seats and the plug threads with a clean, dry
cloth. Then screw in filling plug and safety-head plug assemblies,
applying grease (Par 49 _b_) if plug tends to freeze to seat. Tighten
with wrench. Wipe any spilled fuel from weapon.
40. PRECAUTIONS WITH FUELS.
_a. Flammability._ All fuels used in flame throwers obviously are
highly flammable and must be handled, stored, and used with extreme
care. Diesel oil, fuel oil, and kerosene require the same care as does
gasoline.
_b. Indoor storage._ When it becomes necessary to handle gasoline in
a room or building, the windows and doors should be open and care
taken that no unprotected flame which might ignite the fumes is in the
vicinity. The doors and windows should remain open for a sufficient
length of time afterward to allow any vaporized gasoline to escape.
_c. Flames and sparks._ The presence of open flames, heated stoves,
electrical tools and apparatus, and other equipment likely to cause
sparks must not be permitted. Even nails and metal cleats in shoes are
a potential hazard in the presence of combustible fumes.
_d. Smoking._ “No Smoking” signs must be posted in prominent places
about the premises and the rule against smoking must be strictly
enforced.
_e. Ventilation and cleaning._ The buildings in which fuel is stored
or used must be well ventilated and thoroughly cleaned every day. No
rubbish or other flammable material should be permitted to remain in or
near such buildings.
_f. Spillage._ Care should be taken that fuel is not spilled. Any
spillage should be removed promptly.
_g. Safety cans._ Safety cans should be used, if possible, for storing
small quantities of gasoline, as they have covers that must be forcibly
held open to remove or add gasoline.
_h. Rags._ Metal receptacles with metal lids should be provided for
discarded, oily, or gasoline-soaked rags. These rags must be disposed
of daily.
_i. Electrical apparatus._ Vaporproof incandescent electric lamps,
switches, and other appliances of approved type should be used. Open
switches, relays, and similar apparatus, or motors with commutators,
must not be used where gasoline fumes may be encountered.
_j. Hose._ Flexible metal, rubber, and rubber-metal hose should be
inspected regularly (at least four times a year) and discarded when
noticeably deteriorated.
_k. Toxic fumes._ Gasoline fumes are somewhat toxic and should not be
inhaled.
_l. Leaks._ Leaks must never be neglected, and the fact that gasoline
is a dangerous liquid must always be kept in mind. Inspections for
leaks should be made frequently, particularly at pipe and hose joints.
_m. Fire extinguishers._ Carbon tetrachloride, carbon dioxide, or
foam-type fire extinguishers should be provided and located where they
will be accessible in the event of fire. Sand, not water, should be
thrown on burning fuel if suitable extinguishers are not available.
_n. Leaded gasoline._ Gasoline often contains a poisonous lead
compound. Such gasoline, or fuel containing leaded gasoline, should not
be allowed to touch the body, especially the lips, eyes, open cuts, and
sores.