What Is a Fitting?
Fittings are components used in piping systems for joining, branching, or changing the direction of the flow. There are various types, including bent pipes, branch pipes, and T-pipes made from materials like iron, copper, plastic, and clay. Cast iron and ductile iron fittings are specifically used for water and sewage pipes. Additionally, fittings with non-circular or rectangular cross-sections are also common.
Fittings designed for flow channel alterations and branching come in shapes like bend pipes (with angles ranging from 10 to 180 degrees), cross pipes, Y-shaped pipes, and branching pipes. These are also available in cast iron for water piping systems, and certain standards govern the bend angles. Fittings come in various cross-sectional shapes, including elliptical, semicircular, and grooved.
Uses of Fittings
Fittings are essential in numerous industrial applications where flow direction changes, branching, or merging are required. This includes piping systems in chemical plants, power generation plants, construction machinery, refrigeration and air conditioning systems, and hydraulic circuits. Cast iron and ductile iron fittings find extensive use in water supply, sewage, and gas pipelines.
Beyond flow paths, deformed pipes of diverse cross-sections and materials are utilized as structural materials in various machinery and equipment like textile, food, and printing machinery, as well as in medical equipment, office automation devices, and office supplies.
Principle of Fittings
The choice of material for fittings depends on their intended use and includes steel, copper, stainless steel, alloy steel, cast iron, ductile cast iron, and ceramics. Ductile cast iron, known for its high strength and toughness due to graphite spheroidization, is especially suitable for fluid pressure applications.
The connection methods for fittings vary and include welding, flange connections, and screw connections, with the choice dependent on serviceability. Mechanical joints are often used to connect cast-iron pipes to polyethylene pipes, with rubber rings and flanged fittings ensuring a secure seal.
For steel and alloy steel fittings, common manufacturing methods involve bending and welding thin plates or cold rolls forming various types of steel pipes. Precision-deformed tubes are produced through a drawing process, providing an accurate finish without the need for internal cutting or fittings. Cast iron fittings are typically cast using molds, allowing for a wide range of shapes.