Quick fittings all look the same but they are not.

7 Settembre 2022

Quick couplings were born thanks to the brilliant mind of John Guest in the 60s, first in the industry that put on the market in other sectors. The beverage range dates back to the second half of the 1980s, again by John Guest. International patents have a maximum duration of 20 years, many companies today are on the market with a very similar technology.

At first glance, the quick couplings all look similar, but the differences are considerable

Similar colors and shapes are deceptive, but if we are careful we can spot the differences

The mechanical resistance of the materials is not the same, John Guest fittings in acetal resin are made to withstand accidental impacts. They are also certified and tested materials for their contact with food.

Note: Attention, having a good fitting does not mean that it should be used badly, it often happens to see the male or female cylindrical fittings “pulled” excessively making them work constantly under tension can lead to breakage. The micro cracks that work with difficulty and slowly lead to breakage …

Resistance to exposure to solar UV rays (not the C spectrum of UV sterilizers) is important. Some polymers crystallize and brittle rapidly.

Note: Attention, we strongly advise against the use of polymer quick couplings on UVC sterilizers, especially if exposed directly to radiation. They become embrittled and can snap apart

Dimensional tolerances are important. The water seals are a matter of tenths of a millimeter, it takes very little for a fitting to draw and not seal. Printing at a continuous pace and guaranteeing tolerances on hundreds of thousands of pieces is not a trivial matter. Zero defects do not exist, but there is a big difference between the different manufacturing cases

Wear over time is another important factor, certainly it is a point where John Guest excels and makes the difference even against the fiercest competition. lose elasticity. A broken  gasket can be recognized by eye if it takes on a shape that is no longer toroidal, but with a rectangular section.

Quick fittings over time and at high temperatures

Generic brand fittings on the left OR new on the right OR with some years of work in temperature

John Guest fittings have the advantage of having OR with compounds designed to withstand the stress of time associated with high temperatures. Drinking water treatment systems, where electromechanical parts are present, such as pumps or even refrigeration circuits (cold water dispensers, for example) are subject to the same thermal conditions as the temperature inside the chassis can rise to critical values ​​for the fittings. The professionals of the sector are well aware of the problem, getting your hands inside a plant that has been working for several years can be risky. Cheap fittings, once moved or only touched, begin to draw, this is because the OR gaskets have lost elasticity and are now only plastic.

Note. Water cooling systems generally develop heat inside them due to the action of the compressor. Poor ventilation leads to high temperatures and the fittings tend to “cook”

Finally, we recommend using a tube with a constant section, flexible, without defects in extrusion and that lasts over time. The John Guest tube is simply the absolute best the competition doesn’t hold up. Flexible, with constant sensing, without air bubbles in the extrusion. Over time, it maintains the elasticity necessary to manage the variations in the hydraulic regime within the various systems.