The connectors melting, prevalent in the water supply networks are products traditionally used for their mechanical qualities, corrosion resistance and long service life (over 100!).
Their field of application is vast: drinking water network, raw water network, charged water network, rainwater descent, irrigation, sanitation, heating, etc.
2 main categories of cast iron fittings
Beyond their shape, cast iron fittings are often classified by their connection methods which largely condition the ability of the fitting to connect to pipes of different types (PVC, PER, steel, fiber cement).
These ductile iron fittings malaysia have a male or female thread at each of their ends. All combinations are possible: male-male (MM), female-female (FF) or male-female (MF). Sealing is ensured by conical assembly, by interposing a static seal (flat, O-ring or metallic) or by filling the gaps between the threads (Teflon tape, tow and joint paste or resin).
In socket joints, the ends are provided with a cylindrical part in which the tube slides. A lip or crush seal and a mechanical device provide sealing and locking. In some fittings, these two operations take place automatically when the tube is fitted into the fitting.
A collar with holes is welded, screwed or crimped at each end of the fittings. This assembly involves a symmetrical device on the end of the tube to be assembled. The fixing is carried out by bolting, after interposition of a seal.
Which cast iron for which fittings?
Ductile iron and malleable iron are the two variations of alloys used in the manufacture of fittings. These castings are both ductile and malleable, but depending on their composition one of these characteristics may prevail. Both materials exhibit good weldability and machinability.
Ductility is the capacity of a solid to undergo, before fracture, tensile deformations, without altering its strength, flexibility and molecular cohesion (stretching). It can undergo an elongation of 20 to 30% without damage (against ± 10% for malleable cast iron), so it accepts higher loads.
Ductile iron undergoes less shrinkage during molding, its more regular molecular shape gives it more mechanical precision, allows smoother surfaces, limits sampling (thinner walls) and reduces the risk of internal rupture (straws).
Malleable cast iron
Malleability is the ability of a solid to withstand crushing (hammering) deformations without breaking or excessive hardening. Obtained by annealing, it presents a less favorable ecological balance. This is the most common font.
More flexible but more fragile, malleable cast iron requires a greater thickness of metal. The fittings are therefore heavier and use more energy, thus presenting a less favorable carbon footprint. Malleable iron is best suited for threaded connections.
Cast iron fittings are suitable for all situations
Equal or reduced, there is a wide variety of cast iron fittings: elbows and curves at different angles (up to 180 °), equal tees, connecting sleeves , multi-way Y, cross or side distributors, sleeves , nipples , stoppers, caps, siphons , sight glasses … There are also removable assemblies (union, repair).
The same applies to the dimensions of connections whose common sections are expressed in inches or millimeters. They range from 1/8 ‘(Ø 5-10 mm) to 6’ (152-165 mm) for common uses, up to 1200 mm for collective or industrial applications.