UNDERWATER CUTTING

Question 1

EXOTHERMIC ELECTRODE TYPES:

Answer 1

1) BROCCO, ULTRATHERMIC (BLACK COAT)
2) ARCAIR SEA-JET CUTTING ELECTRODE ( RED COAT)
3) OXY-LANCE ELECTRODE (GREEN)

Question 2

COMMON CHARACTERISTICS:

Answer 2

1) THE ULTRATHERMIC ELECTRODE WILL MELT ALMOST ANY MATERIAL WITH ITS 10,000 DEGREE PLUS TIP HEAT.
2) OXYLANCE AND SEA-JET WILL BURN BOTH FERROUS AND NON-FERROUS MATERIALS

Question 3

OXYGEN PURITY:

Answer 3

1) THE OXYGEN PURITY FOR UNDERWATER CUTTING SHOULD BE 99.5 % OR GREATER.
2) AS OXYGEN PURITY IS REDUCED, SO IS THE CUTTING EFFICIENCY
3) A 1% DECREASE IN OXYGEN PURITY WILL RESULT IN A 25% REDUCTION IN CUTTING SPEED.
4) AT OXYGEN PURITIES OF 95, THE OPERATION BECOMES ONE OF MELTING AND WASHING RATHER THAN CUTTING.
5) COMMERCIALLY AVAILABLE OXYGEN SPECIFICALLY FOR CUTTING IS NORMALLY 99.9% PURE.

Question 4

EQUIPMENT CHARACTERISTICS

Answer 4

1) HIGH VOLUME/FLOW REGULATOR
2) CAPABLE OF 70 CFM.
3) A TWO-STAGE REGULATOR IS RECOMMENDED
4) CAN USE TO A DEPTH OF 300 FSW
5) CUTTING PRESSURE IS 90% OVER BOTTOM PRESSURE.
6) 1/4” ELECTRODE CUTS STEEL UP TO 1/2” THICK
7) 1/4” ELECTRODE LEAVES A NARROW KERF
8) PREFERABLE FOR FINE CUTTING
9) WHEN VISIBILITY IS POOR OR WHEN CUTTING STEEL GREATER THAN OR EQUAL TO 1/2”, THE 3/8” ELECTRODE IS MORE EFFICIENT