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.
A PQM-BT plastic branch T push-quick fitting from Clippard.
Frequency: Next, consider how frequently the hose will be connected and disconnected from the fittings. If you plan to disconnect and reconnect hoses frequently, push-quick fittings are a good choice because they will make this easier. If you plan to set up your system and leave the hoses attached for several years or longer, barb fittings might be a better option.
An XT4-202 male-to-barb fitting made of nickel-plated brass.
Material and media: The material the fitting is made of is also important for determining the fitting’s various physical properties, as well as if it is compatible with the gas. Material choices at manufacturers such as Clippard include stainless steel, brass, nickel-plated brass, and plastic resin. Differing media and the application should be considered when selecting the fitting’s material for the fitting. Suitable media may include air, inert gas, water, liquid, and oil.
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.