247366 - Miller Spoolmate 200 Curved Barrel Liner and Guide Pin Kit

Technical Overview: Miller 247366 Spoolmate 200 Liner Assembly

The Miller 247366 Liner Kit is a critical maintenance component for the Spoolmate 200 Series spool gun, specifically configured for the curved barrel attachment. In MIG welding applications involving push-pull or spool gun systems, the liner serves as the conduit that protects and guides the electrode from the drive rolls to the contact tip. This specific kit addresses the unique tribological challenges presented by the curved barrel geometry, where increased friction points can occur if the liner is not perfectly sized and composed of the correct low-friction material.

This kit includes two primary components: the monocoil liner and the guide pin. The liner is constructed to resist collapsing while maintaining flexibility, a vital feature when navigating the radius of the curved barrel. The guide pin is equally important; it bridges the gap between the drive roll assembly and the liner entrance. A worn guide pin can cause misalignment, leading to wire shaving. These shavings accumulate within the liner, increasing drag coefficient and causing micro-stoppages in wire feed speed (WFS). In aluminum welding, even minor WFS fluctuations can result in burnback or fusion defects.

Installation and Compatibility:
This part is strictly compatible with the Spoolmate 200 (Stock No. 300497) when fitted with the curved barrel. It is not designed for the standard straight barrel or the Spoolmate 100/150 series. Technicians should inspect the liner during every wire spool change, especially when working in dirty environments or with 4043/5356 aluminum wires which are softer and more prone to deformation. Replacing the liner and guide pin simultaneously ensures that the entire downstream feed path is renewed, restoring the gun's duty cycle performance and arc consistency.

By utilizing this OEM kit, operators ensure that the gas flow characteristics within the barrel remain unobstructed by liner kinks, maintaining proper shielding gas coverage at the weld pool. It is an essential spare part for any industrial MRO inventory supporting Miller aluminum welding systems.