40V18 - Tweco 40V18 Conduit Liner for ST-21M MIG Gun, 10ft, .035-1/16"

Product Overview

The ESAB 40V18 is a specialized conduit liner designed for use with the Tweco ST-21M series MIG guns. This component is critical for the proper operation of the wire feeding system, acting as the guide channel through which the welding wire travels from the feeder to the contact tip. Manufactured to precise tolerances, this liner ensures compatibility with the specific geometry of the ST-21M handle and cable assembly.

Technical Specifications

This liner is engineered to accommodate a specific range of wire diameters, specifically from 0.035 inches (0.9 mm) up to 1/16 inches (1.6 mm). This versatility allows it to be used in various fabrication scenarios ranging from light-gauge sheet metal to heavier structural welding, depending on the wire selected. The total length of the conduit is 10 feet, matching the standard cable length of the ST-21M gun configuration. Proper sizing of the liner length is essential to prevent kinking or stretching, which can lead to feed issues.

Construction and Compatibility

Constructed from high-grade spiraled steel, the 40V18 offers the rigidity necessary to prevent collapsing under the pressure of the drive rolls while maintaining the flexibility required for gun manipulation. As a genuine ESAB/Tweco part, it guarantees fitment without the need for modification. It is identified by the industry-standard part number 40V18 and is a direct replacement for worn or clogged liners in the specified equipment series.

Maintenance Application

Regular replacement of the conduit liner is a standard maintenance procedure for MIG welding equipment. Over time, liners accumulate metal shavings, lubricant, and shop dust, which increases friction and causes erratic feeding. The 40V18 is designed for straightforward installation, allowing maintenance personnel to quickly swap out the component and minimize equipment downtime.