Push-to-Connect Fittings: Composite, Brass, and Common Configurations

Push-to-connect fittings are often selected because they reduce assembly time and make tubing connections easier to service. The common material choices are composite and brass, and the body configurations are similar to many compression fitting layouts.

The right fitting still has to match the tube, pressure, application approval, thread end, and service environment.

Composite Push-to-Connect Fittings

Composite push-to-connect fittings usually combine a polymer body with brass screw threads. Compared with all-brass versions, they can reduce weight, cost, and installation labor while still providing durable service in approved applications.

A common comparison is that composite fittings can be about 43 percent lighter than the same brass fitting size. On equipment that uses many DOT-style fittings, that weight reduction can add up across a fleet.

Weight Savings in Vehicle Applications

A tractor-trailer may use dozens of DOT push-to-connect fittings. When 60 to 100 fittings are used on one vehicle, the total weight savings from composite bodies can reach several pounds.

That may look small on one vehicle, but across a fleet it can support payload and fuel-efficiency goals while also simplifying installation.

Brass Push-to-Connect Fittings

Brass body push-to-connect fittings are still common and can be a major improvement over legacy brass compression fittings in suitable applications.

The internal collet and O-ring seal create a comparatively leak-resistant connection without the same tool work required by compression fittings. Brass also resists rust, corrosion, and cold-weather brittleness better than some alternative materials.

Installation Benefits

Both composite and brass push-to-connect fittings can reduce installation time and complexity. The tube is pushed into the fitting, where the collet grips the tube and the O-ring seals around it.

This design can lower labor cost, but it does not remove the need to cut tubing cleanly, insert it fully, and use a fitting approved for the application.

Common Styles and Configurations

Push-to-connect fittings are available in many of the same shapes used for compression connections. Common configurations include bulkhead fittings, elbows, straights, tees, tube-to-NPT fittings, unions, and Y fittings.

Many versions use push-to-connect on one or more ports and male or female NPT on another port. That allows tubing to connect quickly while still adapting into a threaded port or manifold.

Selection Points

Confirm tube size, tube material, pressure rating, DOT or SAE requirement, body material, thread end, temperature range, and whether the system needs composite weight savings or brass durability.

A push-to-connect fitting should be chosen by its approved use and configuration, not only by the speed of installation.