0366549887 - ESAB PSF Steel Liner 1.2mm x 4.5m

Technical Overview: ESAB Steel Liner 4.5M 1.2MM PSF (0366549887)

The ESAB 0366549887 is a specialized steel liner designed for use with the PSF series of MIG welding guns. As a critical component in the wire feeding system, this liner acts as the conduit through which the welding wire travels from the wire feeder to the contact tip. It is manufactured from high-quality, spiral-wound steel, providing the necessary rigidity to support the wire column while maintaining enough flexibility to navigate the curvature of the torch cable without collapsing or kinking.

This specific liner is engineered for a length of 4.5 meters (approximately 14.8 feet), making it suitable for standard length torches as well as extended reach assemblies. It is optimized for use with 1.2mm (0.045 inch) diameter solid steel wires. The internal diameter is precisely calibrated to minimize friction and drag on the wire, which is essential for maintaining a constant wire feed speed (WFS). Variations in WFS caused by a clogged or improper liner can lead to arc instability, burn-back, and erratic weld bead profiles.

In industrial environments, the liner is often the most overlooked consumable, yet it is frequently the root cause of feeding issues. Over time, copper flaking from the wire, shop dust, and lubricant residues can accumulate inside the liner, increasing friction. The ESAB PSF steel liner is designed to resist rapid accumulation of debris, but regular inspection and replacement are recommended as part of a preventative maintenance schedule. This liner is strictly for use with hard wires (mild steel, low alloy steel); it is not suitable for aluminum welding, which requires a Teflon or polymer liner to prevent shaving of the soft wire.

Installation of the 0366549887 follows standard ESAB PSF maintenance procedures. The liner is typically supplied longer than the torch cable to allow for precise trimming at the front end, ensuring perfect seating against the gas diffuser or contact tip adapter. This zero-gap fitment is crucial to prevent wire shaving and gas turbulence within the head assembly. By utilizing genuine ESAB parts, operators ensure compatibility with the PSF torch's retention systems and gas flow dynamics.