TPT January 2008

F ittings , C ouplings & T ubular J oints

W hether the assembly method of choice is soldering, brazing, welding, or by epoxy adhesive – a tubular joint must be strong, leakproof, and corrosion-resistant. The responsibility for satisfying these expectations rests largely with the connecting device, and it is a heavy one. Add economy to the list of essentials, and the pressure is really on for fittings and couplings. As it happens, pressure is their medium. The precision-milled fittings and couplings available to today’s tubemakers are designed to withstand the same conditions –

extremes of temperature, vibration, corrosion, abrasion – that may confront the workpieces they connect. Establishing a connection is much easier when the elements are fabricated to mate. The joint is also far likelier to prove reliable over the service life of the construction. Prior to installation, adapters, unions, tees, and elbows may not make an especially impressive showing. Tubemakers are not deceived. They see each small device for what it is: a precision component, designed for a particular joining requirement, integral to the resulting assembly.

compensating for most variables that lead to failure with other fittings. Brennan double ferrule compression tube fittings can be remade several times, and can withstand heavy impulse and vibration in both vacuum and pressure systems. Requiring no special tools for installation or torque for initial make up and using only geometry, the fitting requires 1¼ turns to be tightly fitted. Supplying a wide range of industries throughout the world, Brennan offers more than 15,000 standard and special products in sizes ranging from 1 / 8 " to 2½". Products include pipe and straight-thread fittings, O-ring face-seal fittings, 37° flare tube fittings, bite-type fittings, DIN fittings, international fittings and adapter unions. Most products are available in carbon steel, stainless steel and brass, and meet or exceed JIC, SAE and other specifications.

Instrumentation fittings for leakproof connection

Brennan Industries Inc, USA, is an international supplier of hydraulic fittings and adapters. The company’s product range includes a line of high-quality, double ferrule, instrumentation grade tube fittings that provide leakproof and torque-free seals at all tubing connections. The tube fitting line reduces the chance of hazardous and expensive leaks in instrumentation, process, pneumatic,

hydraulic, gas and other tubing systems. It consists of the nut, back ferrule, front ferrule and body. When installed, it becomes a five-piece connection with the addition of the tubing providing a solid leak-free joint. The two ferrules are tightly swaged around the tube, and the lack of initial strain on the tubing ensures no tubing wall damage. Leaks are prevented because there is an axial movement along the tube instead of

a rotary motion creating the joint. This axial movement prevents torque from being transmitted from the fitting to the tubing. The fittings are resistant to temperature change, do not significantly reduce flow area, and work with a variety of tube materials. In addition, the two ferrule action supersedes variations in wall thickness, hardness and dimensional tolerance of tube,

fi A selection of fittings from Brennan Industries

Brennan Industries Inc – USA Fax : +1 440 248 7282 Website : www.brennaninc.com

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J anuary 2008

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