21750 - Firepower MT140 Replacement MIG Liner 12ft for .030-.035 Wire

Technical Overview of the ESAB Firepower 21750 Liner

The ESAB Firepower 21750 is a specialized replacement liner designed for the MT140 series of MIG welding guns. This component is critical for the proper mechanical function of the wire feeding system, acting as the conduit through which the welding electrode travels from the wire feeder to the contact tip. Manufactured to precise tolerances, this liner is engineered to accommodate hard steel wires with diameters ranging from 0.030 inches to 0.035 inches (0.8mm - 0.9mm).

Constructed from high-tensile wound steel, the liner provides the necessary rigidity to prevent kinking within the cable assembly while maintaining enough flexibility to allow the operator to maneuver the torch without restricting wire flow. The internal surface is finished to minimize friction coefficients, thereby reducing the load on the wire feed motor and preventing slip or erratic feeding speeds. This 12-foot assembly is cut to length for standard MT140 cable packages, ensuring a correct fit at both the gas diffuser end and the machine feeder connection.

Regular inspection and replacement of the liner are essential for maintaining weld quality. Accumulation of metal shavings, lubricant, and shop dust inside an old liner can increase drag, leading to arc instability and burn-back. The 21750 offers a direct OEM-style fit for Firepower and compatible systems utilizing the MT140 platform, ensuring that maintenance downtime is minimized and equipment performance is restored to factory specifications.