voestalpine Bohler Welding URANOS NX 2200 SMC Classic Manual De Instrucciones página 77

» Grease, varnish, rust or dirt on the filler material.
» Humidity in the filler metal.
» Incorrect arc length.
» Humidity in the welding gas.
» Insufficient shielding gas.
» The weld pool solidifies too quickly.
Hot cracks
Cause
» Incorrect welding parameters.
» Grease, varnish, rust or dirt on the workpieces to be
welded.
» Grease, varnish, rust or dirt on the filler material.
» Incorrect welding mode.
» Pieces to be welded have different characteristics.
Cold cracks
Cause
» Humidity in the filler metal.
» Particular geometry of the joint to be welded.
10. OPERATING INSTRUCTIONS
10.1 Manual Metal Arc welding (MMA)
Preparing the edges
Choosing the electrode
Type of coating
Acid
Basic
Choosing the welding current
» Always use quality materials and products.
» Keep the filler metal always in perfect condition.
» Always use quality materials and products.
» Keep the filler metal always in perfect condition.
» Decrease the distance between the electrode and the piece.
» Decrease the welding voltage.
» Always use quality materials and products.
» Ensure the gas supply system is always in perfect condition.
» Adjust the air flow.
» Check that the diffuser and the gas nozzle of the torch are in good
condition.
» Decrease the travel speed while welding.
» Pre-heat the workpieces to be welded.
» Increase the welding current.
Solution
» Decrease the welding current.
» Use a smaller diameter electrode.
» Clean the pieces accurately before welding.
» Always use quality materials and products.
» Keep the filler metal always in perfect condition.
» Carry out the correct sequence of operations for the type of joint to
be welded.
»
Solution
» Always use quality materials and products.
» Keep the filler metal always in perfect condition.
» Pre-heat the workpieces to be welded.
» Carry out post-heating.
» Carry out the correct sequence of operations for the type of joint to
be welded.
Property
73
OPERATING INSTRUCTIONS
Use
EN