Merit Brass 3611HD-04 Half Coupling 1/4 in 316 Ss Fnpt

Product Description

The MERIT BRASS 3611HD-04 is a 1/4 inch female NPT half coupling designed for threaded pipe connections in high-pressure fluid and gas systems. Machined from 316/316L stainless steel, this fitting offers strong resistance to corrosion, including chloride-bearing environments, making it well suited for marine, chemical, and industrial process lines. The half coupling is rated to 3,000 psi, supporting demanding service conditions. Licensed plumbers, pipefitters, and industrial maintenance technicians typically install this type of fitting where a branch connection or end connection is needed on a pipe without requiring a full coupling.

This half coupling is appropriate for residential and commercial plumbing, HVAC hydronic systems, compressed air lines, and light industrial process piping. The FNPT end accepts standard tapered male NPT pipe threads. The 316/316L dual-certified material grade suits applications where weld-quality or low-carbon stainless is specified to reduce sensitization risk. Typical install scenarios include connecting a pipe run to a valve, gauge, or instrumented port where only one threaded engagement is required.

Key Features

• Dual-certified 316/316L stainless steel construction for corrosion resistance in aggressive environments
• 3,000 psi pressure rating for high-pressure fluid and gas service
• 1/4 inch FNPT connection accepts standard tapered male NPT threads
• Threaded end connection for tool-only installation without welding
• Half coupling design provides a single-end threaded branch or termination point
• Compact, low-profile fitting suited for tight installation spaces

Compatibility

Designed as an OEM-style replacement or new-installation fitting compatible with 1/4 inch NPT threaded pipe systems requiring 316 or 316L stainless steel construction.

Installation Notes

Installation should be performed by a licensed plumber or pipefitter following applicable IPC or ASME B31 piping codes. Depressurize and isolate the line completely before threading in or removing any fitting. Apply appropriate thread sealant or PTFE tape to male NPT threads before assembly. Do not over-torque the fitting, as stainless steel threads are susceptible to galling.