PU Series Straight Union Pneumatic Fitting

PU Series Straight Union Pneumatic Fitting

This is a straight push-in connector for pneumatic tubing. Both ends are for tube insertion, so it is used when two tubes need to meet in one line.

On a machine, this kind of fitting is often added when the original tube is not long enough. It can also be used after a damaged tube section has been cut out.

How to Use It

Cut the tube as flat as possible. If the end is rough, trim it again.

Push one tube into one side of the fitting. Push the second tube into the other side. After that, pull both tubes lightly by hand. If they do not slide out, the fitting has gripped the tube.

When the tube needs to be removed, turn off the air first. Press the blue ring and pull the tube out.

Where It Fits

PU straight unions are common in air lines for cylinders, valves, packing machines, small automatic equipment and repair work. They are not used for changing direction. They are mainly for keeping the tube run straight.

Picking the Size

Check the outside diameter of the tube. A 6 mm tube needs a 6 mm fitting. An 8 mm tube needs an 8 mm fitting.

This PU type is for two tubes of the same size. If one tube is larger and the other is smaller, use a reducing union instead.

Notes Before Installation

Make sure the tube is clean before pushing it in. Do not push the tube in from an angle. Leave some room near both blue rings, because they need to be pressed when the tube is removed.

After connecting the air, check both ends. If there is leakage, remove the tube, cut the end again, and insert it once more.