0558009408 - ESAB PT-31 Micro Nozzle 0.8mm (Pack of 5)

Technical Overview of the ESAB 0558009408 Micro Nozzle

The ESAB 0558009408 Micro Nozzle is a critical consumable component designed specifically for the PT-31 and PT-31XL series of plasma cutting torches. Engineered with a precise 0.8mm (0.031 inch) orifice, this nozzle is calibrated to constrict the plasma arc effectively within the 30 to 40 Ampere range. The constriction of the arc is fundamental to plasma cutting physics; by forcing the ionized gas through this small diameter, the velocity and energy density of the plasma stream are significantly increased, allowing for clean, narrow kerf cuts on conductive metals.

Manufactured from high-grade copper alloy, the nozzle is designed to withstand the intense thermal loads generated during the plasma process. The geometry of the nozzle bore is critical for maintaining laminar gas flow, which directly impacts cut quality and angularity. As the pilot arc transfers to the workpiece, the nozzle directs the main cutting arc. Over time, the orifice will erode due to the high heat and velocity of the plasma gas. This erosion leads to a widened arc, reduced cutting speed, and increased dross. The 0558009408 is designated as a "Micro" nozzle, indicating its suitability for finer, lower-amperage applications where detail and precision are prioritized over raw severance thickness.

This specific SKU is supplied as a pack of five, ensuring that operators have sufficient replacement stock to maintain continuous operations. It is the standard nozzle for several legacy and current ESAB power sources, including the HandyPlasma 380 and 550 systems. Proper installation requires ensuring the swirl baffle and electrode are also in good condition to prevent premature nozzle failure, such as double-arcing, which can instantly ruin the orifice geometry.