06 personal protection, Personal protection -3, Introduction auto-darkening welding helmet – Tweco Auto Darkening Welding Helmet User Manual
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INTRODUCTION
AUTO-DARKENING WELDING HELMET
2-3
Manual 0-5045
2.06 Personal Protection
!
WARNING
Prior to welding check operation of the filter lens, if the lens does not darken DO NOT COMMENCE WELDING.
If during welding the filter does not darken IMMEDIATELY STOP WELDING.
The radiation from an electric arc during the welding process can seriously harm eyes and skin. It is essential that
the following precautions be taken:
When electric arc welding, it is a requirement to use a welding helmet or welding handshield that complies to a relevant
standard. Protective filter lenses are provided to reduce the intensity of radiation entering the eye thus filtering out
harmful infra-red, ultra-violet radiation and a percentage of the visible light. Such filter lenses are incorporated into
this Welding Helmet. To prevent damage to the filter lenses from molten or hard particles an additional hard clear
glass or special plastic external cover lens is provided. This cover lens should always be kept in place and replaced
before the damage impairs your vision while welding.
It is important to ensure that the helmet is adjusted to the correct shade level prior to the commencement of welding.
The table below can be used as a guide to select the filter lens shade level for differing applications.
Welding Process
Arc Current in Amps
Recommended Shade
Manual Metal Arc Welding (Stick)
60 − 100
#9
100 − 150
#10
150 − 200
#11
200 − 300
#12
300 − 450
#13
Gas Metal Arc Welding (Mig) with Heavy Metals
Less than 125
#9
125 − 175
#10
175 − 250
#10
250 − 350
#12
350 − 450
#13
Gas Metal Arc Welding (Mig) with Light Alloys
Less than 175
#10
175 − 225
#11
225 − 300
#12
300 − 400
#13
Gas Tungsten Arc Welding (Tig)
30 − 70
#9
70 − 125
#10
125 − 200
#11
200 − 300
v#12
300 − 350
#13
Air – Arc Gouging
Less than 175
#10
175 − 200
#11
200 − 250
#12
250 − 350
#13
Plasma Arc Cutting
Less than 125
#9
125 − 150
#10
150 − 175
#11
175 − 250
#12
250 − 400
#13
Plasma Arc Welding
100 − 125
#9
125 − 175
#10
175 − 225
#11
Note: The term “Heavy Metals” applies to steels, alloy steels, copper and its alloys, etc.
Refer to standard EN 379:2003 for comprehensive information regarding Table 1.