Jasic MIG250P, Руководство пользователя

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19
0.8 40
～
200 60
～
100
1.0 70
～
250 80
～
120
7.4.2.
Welding speed selection
Welding quality and productivity are main consideration. If welding speed is too fast with poor protective
effect which accelerates cooling speed, welding toughness is lowered which is not good for weld shaping; if
welding speed is too slow, it is easy to burn through weldment that results in large welding bead. Welding
speed is usually 50cm/min or less in actual production.
7.4.3.
Welding wire extension selection
With increasing welding wire extension and shallow penetration, welding wire fusion is accelerated which
improves the productivity; but if extension is too long, welding wire is easily broken with large spatter, causing
unstable welding. Thus, it is generally 10~15 times of wire diameter.
7.4.4.
Gas flow selection
Protective effect is main consideration. Because inside corner weld is better protected than outside
corner weld, flow should be low. As for solid wire welding, shielding gas should be reduced or removed. Below
is figure.
Welding method
Φ0.8 Φ1.0 φ1.2
Thick wire with max
current welding
Gas flow (L/min) 5
～
10 5
～
12 15
～
20 20
～
25
7.4.5.
Extension cord modification
Synergic voltage of this welder is stipulated based on standardized 3m welding cable (25mm²). When
extension cord is applied, welding voltage becomes low and unstable caused by low arc voltage due to line
impedance. Here is extension cord modification. For instance, if 25mm² copper cable of welding loop
(r
esistance: 0.868Ω/km@20
℃
) lengthens every 5m and increases every 100A welding current, synergic
voltage should increase every 0.45V.
7.5. Welding process quick search for MIG (for reference)
Welding stability, welding quality and productivity depend on welding current and voltage which are
selected according to the requirement of welding wire diameter, needed droplet transfer form and
manufacturing technique with purpose of ensuring welding quality.
7.5.1.
Common welding current and voltage application under CO2 MIG for reference
7.5.1.1. I type butt welding parameters