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FAQ's



How many balloons can I fill with my helium tank?

That depends on the size of the balloons being used and the size of the tank. Temperature and tank pressures can also be a factor. See the chart below for approximate numbers: (These are assuming you do not overfill balloons and start with a full tank)

Helium Cylinder Size Tank Pressure 9'' 11'' 14'' 16''
40 cu.ft./ "V" Cylinder 2200 psi 125 60 35 25
80 cu.ft./ "Q" Cylinder 2200 psi 250 120 70 50
122 cu.ft./ "S" Cylinder 2200 psi 340 180 90 75
244 cu.ft./ "K" Cylinder 2200 psi 680 360 180 150
291 cu.ft./ "T" Cylinder 2200 psi 940 500 250 200

What do the terms TIG and MIG stand for?

TIG [Tungsten Inert Gas] and MIG [Metal Inert Gas] refer to two electric welding processes in common use today. They are very different and each has characteristics making them suitable for particular welding applications. In brief;

TIG welding uses a non-consumable electrode that provides the arc and a separate filler material in the form of a rod. In addition, the TIG torch delivers a shielding gas to the weld site to minimize weld oxidation and/or alter the characteristics of the weld metal. In technique it is much like handling a oxy-acetylene torch though it is an electric process rather than flammable gas. It produces high quality welds and is especially suitable for aluminum and stainless steel metals.

MIG welding uses a device to automatically feed welding filler material into the weld site. The material is in the form of wire and the wire itself is the electrode. As it is with the TIG torch, the MIG torch delivers shielding gas to the weld site although welding wire is available that produces its own shielding gas in much the same way flux coated stick electrodes do.

The American Welding Society refers to these two processes as GTAW [gas tungsten arc welding] for TIG and GMAW [gas metal arc welding] for MIG.

What is the difference between brazing and welding?

Brazing is a process where metal is joined together by heating the base metal to approximately 800°F and then using a non-ferrous filler metal having a melting point below that of the base metal. The filler metal melts and adheres to the base metal. The base metal does not melt and there is no fusion as in welding processes.

Most commercial metals can be brazed. Although brazed joints have a relatively high tensile strength they do not possess the full strength properties of conventional welding techniques. One very useful characteristic of brazing is its ability to join dissimilar metals.

What do the numbers on welding rod mean?

Arc welding electrodes are coded by the American Welding Society [AWS]. Each AWS number gives complete information about the electrode.

Classifications of mild and low alloy steel electrodes are based on an 'E' prefix and a four or five digit number. The first two digits [or three, in a five digit number] indicate the minimum required tensile strength in thousands of pounds per square inch [psi]. The next to last digit indicates the welding position in which the electrode is capable of making satisfactory welds. [1 = All positions, 2 = Flat position and horizontal fillets]. The last digit indicates the type of current to be used and the type of covering on the electrode [see fig. 1].

fig. 1

FOURTH DIGIT TYPE COATING CURRENT
0 ORGANIC DC+ only
1 ORGANIC AC, DC+, DC-
2 RUTILE AC or DC-
3 RUTILE AC, DC-, DC+
4 RUTILE, IRON POWDER AC, DC-, DC+
5 DC+ only
6 LOW HYDROGEN AC or DC+
7 LOW HYDROGEN AC, DC-, DC+
8 MINERAL IRON POWDERLOW
HYDROGEN, IRON POWDER
AC or DC+

Example: E6010

a. The prefix [EXXXX] designates an arc welding electrode.
b. The first two digits [E60XX] indicate a minimum tensile strength of 60,000 psi.
c. The next digit [EXX1X] indicates position; All positions.
d. The last digit [EXXX0] indicates an organic coating and DC+ current

POWER CABLE

Wire Size Max Amp @ 100 ft. Voltage Drop / 100 ft.
4 105 2.6
6 80 3.2
8 55 3.42
10 40 4.0
12 25 4.0
14 20 6.4

WELD CABLE

Amps

Cable Sizes Required per Lengths

0 - 50 ft.

100 ft.

150 ft.

200 ft.

250 ft.

100

150

180

180

200

8

6

5

4

3

4

5

4

4

3

3

3

3

3

2

2

2

2

2

1

1

1

1

1

1/0

200

200

225

225

250

2

2

4 or 5

3

3

2

2

3

3

3

2

2

2

2

2

1

1

1

1

1

1/0

1/0

1/0

1/0

1/0

250

250

300

2

1

1

2

1

1

1

1

1

1

1

1/0

1/0

1/0

2/0

325

350

400

400

500

600

600

600

650

650

2/0

1/0

2/0

3/0

2/0

3/0

2 -1/0

2-1/0

3/0

2-1/0

2/0

1/0

2/0

3/0

2/0

3/0

2 -1/0

2-1/0

3/0

2-1/0

2/0

2/0

2/0

3/0

3/0

3/0

2 -1/0

2-1/0

4/0

2-1/0

2/0

2/0

3/0

3/0

3/0

4/0

2-2/0

2-2/0

2-2/0

2-2/0

3/0

3/0

4/0

4/0

4/0

2-3/0

2-3/0

2-3/0

2/3/0

2-3/0

What shielding gas should I use?

The primary purpose of shielding gas is to displace the air in the weld zone to prevent contamination of the weld zone by oxygen, nitrogen, or water vapor. Shielding gas for TIG welding can be argon, helium, or a mixture of argon and helium. Argon is the most popular. Argon has greater cleaning action and provides a more stable arc than Helium. Argon is heavier than air and provides a blanket over the weld that protects it from contaminants. Helium is lighter than air, requires a higher gas flow than argon and is more expensive to use. Helium allows greater penetration and faster welding speeds because the arc is hotter in the helium atmosphere than in the argon atmosphere. For MIG welding a mixture of argon and helium is sometimes used in welding metals that require greater heat. Argon is used for most TIG welding applications.

Argon [A], helium [He], and carbon dioxide [CO2] are the principal shielding gases used. Oxygen [O2] is used as an additive to stabilize the welding arc. Listed below are some of the more common gas and gas mixture applications.

BASE METAL

SPRAY TRANSFER

DIP TRANSFER

PULSED SPRAY

Stainless Steel

A + .5% O2

A + 1% O2

A + 2% O2

90% HE + 7.5% A + 2.5% CO2

A + .5% O2

A + 1% O2

A + 2% O2

Carbon and

Low Alloy Steel

A + 1% O2

A + 2% O2

A + 5% O2

A + 5% CO2

A + 8% CO2

CO2

A + 25% CO2

A + 8% CO2

A + 5% CO2

A + 1% O2

A + 2% O2

A + 5% O2

A + 5% CO2

A + 8% CO2

Aluminum and

Magnesium

Argon

Helium

A + 25% HE

A + 75% HE

A + .15% O2

 

N/A

Argon

A + 25% HE

A + 75% HE

A + .15% O2



 
 
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