Cutting And Piercing Method; Beginning Of Cutting Operation - Huawei CG1-2 Operating Instructions Manual

5. Neutral flame ensures good quality cut surfaces. (Oxygen flame may be used for bevel
cutting.)Oxygen flame causes short cutting-oxygen current, allowing slugs to adhere, melting
the upper edge of the cutting surface, and causing adverse effects on the cut surface. Similar
defects will result when the cutting oxygen pressure is too high.

4.3 Cutting and piercing method

1. Cut in from the end of steel plate.
2. Pierce steel plate before cutting.
3. Drill a hole before cutting.
■ Piercing method
1) Ignite and adjust the flame.
2) Thoroughly preheat the cut-in point until it is white hot.
3) Open the cutting oxygen valve to pierce the steel plate. The tip should be about 15-20
mm from the plate to prevent slag from splashing onto the tip and adhering there,
which will shorten the working life of the tip.

4.4 Beginning of cutting operation

1. Release clutch of machine and pull the torch on the edge of wing plate edge which is on
one side of H structural section. Put torch horizontally. Then put quick knob in the preheating
position. Ignite torch and adjust flame. (Refer to quick distributor adjustment in detail)
2. When use preheating flame, set quadruple switches in the descending position and push
quick knob to low tip and be close to surface of wing plate. Adjust the distance between tip
and wing plate. The distance range is about 7 to 10mm. Then close the clutch.
3．Move tip center under the lower limb of wing plate 5mm and torch stops descending. At
that moment, set torch descending spacing switch.
4．Set cutting speed.
5．Put quadruple switch in the ascending position. Tip center moves upwards and aligns
cutting starting point which is near the wing plate. And preheat cutting starting point. (as
shown in the diagram 1)
- 12 -
CG1-2A H Beam cutter