3/4 Lead-Free Brass Union Fittings

A 3/4" brass union connects two pipe sections while allowing quick disconnection for maintenance, repair, or component replacement without cutting the pipe. They're commonly used in plumbing, industrial fluid lines, and equipment connections requiring periodic servicing.

Unlike a fixed coupling, a union fitting uses three parts—two end pieces and a center nut—that can be tightened or loosened by hand or wrench, allowing disconnection without cutting or re-threading the pipe. This makes maintenance and part replacement significantly easier.

Most 3/4" brass unions use NPT (National Pipe Thread) tapered threads, the standard threading specification for pipe fittings in the United States, ensuring a tight seal when properly installed with appropriate thread sealant.

Brass unions are rated for a range of pressure and temperature conditions depending on wall thickness and design. For high-pressure industrial or oilfield applications, confirm the specific pressure rating with your supplier before installation.

Brass unions are commonly used in water, air, and select fluid applications. Compatibility with gas lines depends on local plumbing codes and the fitting's specific rating, so verify code compliance for your intended use case before installation.

Regularly inspect the union nut and mating surfaces for corrosion or wear, ensure proper thread sealant application during installation, and avoid over-tightening, which can damage the sealing surface and cause leaks over time.