When setting up a network of controllers and actuators controlled by pneumatics, designers and engineers have options as to what fittings will be used on the various components. Here are a few things they should consider when deciding between barb fittings and push-quick fittings for specific applications.
Tubing size: The first thing to consider is tubing size. Barb fittings are measured by tube I.D. (inner diameter), while push-quick fittings are measured by tube O.D. (outer diameter). If the tubing is already in place or decided upon, be sure to match the tubing to the appropriate fitting for a tight seal.
Durometer of tubing: Finally, consider the durometer of the tubing. Barb fittings create a better seal on a slightly softer hose, while push-quick fittings are easier to use with a stiffer hose. For example, Clippard recommends using 85A durometer polyurethane tubing for barb fittings and 95A durometer polyurethane tubing for push-quick fittings.