Harris 4400160 Manual Del Usuario página 3

Adjusting Pressure
To identify equal pressure or universal pressure torches, set 25 ± 5 PSI
on oxygen supply, disconnect fuel gas hose and check valve with mixer
or cutting attachment on torch. Open all gas valves and check fuel gas
inlet. If pressure is found, equipment is equal pressure type. If suction is
noted, equipment is universal pressure type. Reconnect check valve and
hose and purge thoroughly before lighting.
Note:
1. For Equal Pressure Torches (sometimes called "medium pressure").
This equipment requires fuel gas pressures above 1 PSIG. Positive
pressure is used to mix fuel gas with oxygen.
2. For Universal Pressure Torches (sometimes called "low pressure").
This equipment operates with less than 1 PSIG fuel gas pressure.
Oxygen, at pressure, creates suction that pulls the fuel gas into the
mixer.
Figure 8.
Regulator Opening Fuel
Adjusting Key
Gas Cylinder Valve
1. Be sure both regulator adjusting keys (Fig. 8) are free, by turning
counter-clockwise until loose.
2. Slowly open fuel gas cylinder valve (Fig. 9) not over one (1) turn and
set regulator key for required operating pressure. Keep handle or
valve wrench on cylinder valve to allow rapid shutdown.
3. To prevent a sudden increase in pressure, slowly open fully the
oxygen cylinder valve (Fig. 10). and set regulator to required
operating pressure.
Note: The oxygen cylinder valve should always be wide open when
operating.
4. Test connections and regulators for leaks by brushing with a soapy
water solution while observing for presence of any bubbles. If
bubbles are observed, tighten fittings and wipe off soap solution.
Refer to Regulator Test in the Maintenance instructions.
Operating Instructions: Lighting Torch for Acetylene Fuel Gas
1. Purge system. Refer to Maintenance Instructions.
2. Open torch fuel "GAS" valve (Fig. 11) approximately one half turn and
ignite fuel gas.
3. Keep opening torch fuel "GAS" valve (Fig. 12) until flame stops
excessive smoking and leaves the end of tip about 1/8", then reduce
slightly to bring flame back to tip.
4. Open torch oxygen "OX" valve (Fig. 12) until a bright inner cone
appears on the flame.
Note: The point at which feathery edges of flame disappear and a sharp
inner cone is visible is called the "Neutral Flame."
Special Purging Sequence
1. Open Fuel Gas ¾ - 1 turn
2. Open Pre Heat Oxygen Valve and Allow to Purge. (5 seconds / 50 ft.
of hose)
3. Close Fuel Gas Valve then Oxygen P.H. Valve
4. Allow Gasses to Dissipate Before Attempting Ignition
Lighting Torch for Other Fuel Gases: (Propane, Propylene & Natural Gas)
1. Open Fuel Gas Valve ½ - ¾ Turn
2. Open Oxygen Valve Slightly 1 ⁄8 - ¼ Turn
3. Ignite With an Approved Igniter
4. Adjust to Desired Flame
a) Use Pre Heat Oxygen Valve to Adjust Intensity
Figure 9. Figure 10.
Opening
Oxygen valve
b) Generally Fuel Gas Valve Needs No Adjustment
Note: A neutral flame has a shortened, sharply defined inner cone, blue in
color. Intensity of the color depends on fuel gas used, but all gases
will show lighter blue as oxygen is added past the neutral point.
Figure 11.
Igniting Fuel Gas
Adjusting flame
Shutting Down Equipment
1. First close torch oxygen "OX" valve, then close torch fuel "GAS"
valve (Fig. 12). This sequence will prevent flame from popping out at
shut down.
2. Close supply valves for both gases (FIgs. 9 and 10).
3. Bleed off all oxygen at torch "OX" valve, (Fig. 12) then close the
valve.
4. Bleed off all fuel gas at torch "GAS" valve, (Fig. 12) then close the
valve.
5. All pressure gauges should read 0 PSI. Turn both pressure regulator
adjusting keys (Fig. 8) counterclockwise until loose.
Gas Welding and Steel Flame Cutting: Basic Gas Welding Procedures
Gas Welding. Gas welding is a method of joining similar metals by
heating the adjacent surfaces to the melting point with an oxy-acetylene
flame, and allowing the two parts to fuse together, with a filler metal
being required on materials 3/16" thick or more. The resulting weld is
as strong as the parent metal.
Clean all metal. All metal should be cleaned before welding. Oil, grease,
rust, scale, or other impurities will affect the weld quality, or tensile
strength. Metal 3/16" or more thick should be bevelled before welding,
and when bevelled sides are joined, a filler rod of the same material is
necessary.
Welding Tip Chart. There are a variety of tip sizes available to handle
welding or brazing different thickness of material. For complete
information regarding material thickness and pressure settings
refer to the current product catalog or visit our website at www.
harrisproductsgroup.com. If too large a tip is used and the flame
softened, the tip heats up unnecessarily and is often accompanied by
a popping noise which splatters the weld puddle. Too hot a flame burns
the steel, and too small a flame will not heat the metal to the proper
temperature.
Proper Flame. A neutral flame (Fig. 13) is used for almost all gas welding.
The oxy-acetylene flame consumes all oxygen in the air around the
welding area, which leaves an uncontaminated weld area and a weld of
maximum strength. An oxidizing flame is rarely used, but a carburizing
flame is occasionally helpful when flame hardening or brazing.
NEUTRAL
White
Nearly Colorless
CARBURIZING
Intense White
with Feathery Edge
OXIDIZING
Figure 13.
Neutral, Carburizing and oxidizing Flames
Figure 12.
Bluish to Orange
Light Orange
White
Nearly Colorless
White
Bluish to Orange
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