Midland Industries 18163 Brass Compression Adapter 5/8x3/4 Fnptf

Product Description

The MIDLAND INDUSTRIES 18163 is a brass female adapter fitting designed to connect compression-style tubing to a female NPT threaded port. The fitting transitions a 5/8 inch compression connection on one end to a 3/4 inch FNPTF (female national pipe thread fuel) connection on the other. Constructed from brass, it is rated for service up to 150 psi across a temperature range of -65 to 250 degrees F. The 1.12 inch hex body allows standard wrench engagement for secure installation. This adapter is suitable for use in plumbing, HVAC, and light industrial applications where a reliable compression-to-threaded transition is required.

This adapter is intended for use with copper, aluminum, and thermoplastic tubing in residential and commercial installations. Typical applications include connecting refrigerant or fluid lines to threaded valve bodies, manifolds, or equipment ports. The FNPTF thread form provides a pressure-rated sealed connection without the need for a separate ferrule at the threaded end. Its compact profile and standard hex sizing make it straightforward to install in tight spaces where inline transitions are common.

Key Features

• 5/8 inch compression inlet connects directly to copper, aluminum, or thermoplastic tubing without soldering
• 3/4 inch FNPTF outlet provides a pressure-rated threaded connection to NPT-compatible ports
• Brass construction offers corrosion resistance and durability across a wide service range
• Rated to 150 psi working pressure for reliable performance in pressurized systems
• Operating temperature range of -65 to 250 degrees F suits both chilled and hot fluid service
• 1.12 inch hex for standard wrench engagement during installation and removal

Compatibility

Designed for use with copper, aluminum, and thermoplastic tubing in compression fitting applications. Compatible with any NPT-threaded port or valve accepting a 3/4 inch FNPTF connection.

Installation Notes

Installation should be performed by a licensed plumber or qualified HVAC technician in accordance with applicable local codes and IPC guidelines. Shut off and depressurize the system completely before removing or installing any compression fittings. Use a backup wrench on the mating fitting to prevent twisting the tubing or connected equipment during tightening. Inspect the compression ferrule and tubing end for burrs or damage before assembly to ensure a leak-free seal.