Fittings 101
Barbed
 In most cases you'll need to attach your tubing to other equipment or to another piece of tubing. Fittings, also known as connectors, are a common means to accomplish this, and they come in many different materials — polyethylene, nylon, PVDF, fluoropolymer, stainless steel, brass — so you can select the best match for your application.
 There are many types of fittings, and we'll start by focusing on barbed fittings. As the name states, these fittings have a single barb or multiple barbs on at least one end. The barbed end is inserted into the tubing. The function of the barbs is to grip the interior wall of the tubing, without damaging the wall, to assist with holding the fitting in place.
Barbed fittings work best with soft tubing (flexible PVC, polyurethane, silicone, thermoplastic rubber), as the tubing must give a bit to fit around the barbed end. Leaks can occur when there isn't a good fit, i.e. the fitting is too small. In fact, the O.D. of the barbed area on the fitting must be larger than the I.D. of the tubing, and there should be some resistance when the fitting is inserted into the tubing. As an example, .250" I.D. tubing (1/4") should use a barbed fitting with a barb O.D. of at least .270".
Barbed fittings are usually applied by hand without tools, and typically clamps or tie wraps are used to securely attach the fitting to the tubing and ensure a good seal. Sometimes on lower pressure applications, clamps may not be necessary, but that is the exception rather than the rule and should always be determined by testing the connections as they will be used in the field.
 Tubing and fitting materials must mate well with each other as well as to the application. For instance, a brass barbed fitting may not be a good match for silicone tubing. The barb design could be too sharp for the silicone material, cut into the wall, and possibly cause a failure. Polyurethane tubing, which is much more resilient and resistant to tearing than silicone, may be a better choice for this type of brass barbed fitting. Less aggressive barb designs are recommended for silicone tubing, along with plastic or lined metal clamps.
NewAge offers its brand of plastic barbed fitting, Thermobarb®, in five materials: nylon, polyethylene, PVDF, polypropylene, and brass. Fitting styles vary from simple tees (T's), wyes (Y's), and 90° elbows, to male and female adapters, and to swivel styles and those designed for single use/disposable applications.
Click here to request a Thermobarb sample, or call us with your application questions.
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