Pipes are the essential component of a home and because water runs through them so that we can get enough water for our conveniences and requirements. Pipes are like veins of our body; they keep plumbing equipment active and give them a purpose to exist in this world. Today we are going to explore the pipes we use at home, classified by their materials of manufacturing. Enjoy the read, everyone 😊
1. Plastic Pipes
A. PEX (Cross-Linked Polyethylene)
- The technology of Crosslinking was first developed in Europe in the late 1960s and is tested extensively for its durability and material performance around the world with a history of 50 more successful working years.
- Standard Dimension Ratio (SDR) 9 PEX tubing mainly has a standard hydrostatic pressure (SDP) ratings 160psi at 73 degrees Fahrenheit, that is, 1105 kPa at 23 degrees Celsius and 100 psi at 180-degree Fahrenheit (690 kPa at 82 degrees Celsius).
- The pipes with larger diameters are primarily available in straight lengths, while most diameters of PEX tubing and pipe are sold in both coils and straight lengths. PEX tubing in hot and cold-water distribution systems can generally be installed in place of copper tubing on a size-for size basis and thanks to its smooth inner wall and flexibility, which enables installers to avoid using elbow fittings in the majority of construction projects.
- Where the polymer chains are chemically linked, the material will undergo a change in molecular structure using mechanical or chemical processes that will result in a much more version of polyethylene and it will make the PEX a “semi-thermoset” polymer, providing excellent long-term stability. And the outcome material gives out the improved properties like, elevated chemical resistance, flexibility, performance and temperature strength, resistance to slow crack growth (SCG), environmental stress crack resistance (ESCR), toughness and abrasion.
- Through radical reactions, Polyethylene can be crosslinked using several technologies and all methods consist of the linking between a single strand of HDPE to form a denser network or matrix. The crosslink density is determined by the number of links between the HDPE molecules and that also determines the physical properties of the material. Common methods state below:
- Peroxide: The process sometimes referred to as PEXa Process and the method employs organic peroxides that, when heated, as the HDPE compound is extruded, generate reactive free radicals that splice PE chains together.
- Silane: Mostly known as the PEXb Process, this method involves, such as with steam curing, grafting a reactive silane molecule to the backbone of the polyethylene, and when subjected to moisture and heat, which allows the HDPE compound to crosslink after extrusion as pipe.
- Electron Beam: Known in the world as PEXc Process, and it consists of subjecting a high energy electron dose to the extruded HDPE pipe.
B. CPVC (Chlorinated Polyvinyl Chloride)
- As defined in ASTM specification D1784, CPVC is a thermoplastic pipe and fitting material made with compounds meeting the requirements of ASTM Class 23447. The applications include fire suppression systems, corrosive fluid handling in industry and mainly potable water distribution for commercial and residential purposes. The industrial CPVC pipes are manufactured by extrusions in sizes from 1 by 4 inches to 12 inches diameter to Sch 40, Sch 80 and SDR dimensions.
- The CPVC piping has a 400psi pressure rating at room temperature, and a 100psi pressure rating at 180-degree Fahrenheit, which is suitable for cold and hot water distributions. We use them because the materials used to manufacture CPVC are resistant to many of the everyday household chemicals. And they are fire resistant because they do not support combustion, which means they are not able to burn without an external fuel source. Properties like that make CPVC an excellent alternative to steel and copper pipe for applications such as fire sprinkler.
C. PVC (Polyvinyl Chloride)
- In plastic piping, one of the most universal and versatile types and in use for more than 80 years, applications span multitude of industries around the world. They are exceptionally strong and durable compared to metal piping with little to no risk of succumbing to thermal expansion or contraction and they are completely corrosion resistant as well.
- They are mainly used for the manufacturing of sewage pipes, water mains and irrigation systems and properties which make them cost-efficient and sustainable . They are easy to install, lightweight, strong, durable and easily recyclable. Compared to piping made from materials like cast iron or concrete, the smooth surface of PVC encourages faster water flow due to the lower amounts of friction in inner walls of the pipe. According to international standards like DIN 8061, ASTM D1785 and ASTM F441, PVC pipes can be manufactured in various lengths, wall thicknesses and diameters.
- The common operations in the making of PVC are: Providing the PVC twin screw extruder with raw material pellets or powder, in multiple extruder points the machine heat and melt the provided raw material, to shape into a pipe the resulting substance will extrude through the die which leads to the cooling of newly shaped pipe and cutting the new pipe into the desired length considering the requirements of the industrial standards.
D. ABS (Acrylonitrile Butadiene Styrene)
- The material is a thermoplastic resin which is strong and durable and the piping systems are easier and less expensive to install than metal piping and because of the smooth interior finish the fluid will go through them hassle free and without much friction. One thing to consider mainly is, even at low temperatures they resist the mechanical damages and that helps to gain longevity in hard conditions. The pipe performs well at an operational temperature up to 140 degrees Fahrenheit or 60 degrees Celsius.
- In the beginning of 1950, the ABS pipe and fittings were originally developed for mainly use in oil fields and in chemical sectors but the residential usage approval process of the ASTM standard for ABS pipe and fittings began in 1967.
- In commercial and residential constructions, contractors have installed approximately around more than 10 billion feet of ABS pipes in the US alone. The pipes are available in Schedule 40 dimensions in solid-wall and cellular-core construction and for DWV applications, these two forms may be used interchangeably.
2. Metallic Pipes
A. Copper
- The tubes are mainly used in water supply lines and refrigerant lines like heating, ventilation and air-conditioning (HVAC) systems. The copper pipes contain around 99.9% pure copper and the extraction process is considered as hard and critical compared to its fabrication and installation. And the pipes are made JIS and ASTM standards for commercial use as well.
- The two standard pipes are manufactured to meet different roles. The JIS H3300 C1220T copper pipe is more suitable for potable water or water works like showering systems to overall water distributions in home or commercial purposes. But in the case of ASTM B88 copper tube is more likely suitable for heat sensitive processes such as air conditioning and refrigeration.
B. Galvanized Steel
- The steel tube is then coated with Zinc to act as a protective layer that helps keep the tube’s durability high and it also minimizes the corrosion chances of the steel pipe as well and the Zinc coating process is generally known as Galvanization. These tubes are best used in industrial or commercial projects like agriculture, automotive and construction purposes.
- The one thing to consider is, the welder who is working with galvanized steel should have to take precautions from harmful Zinc fumes and chemicals that can cause health issues like breathing problems and so be careful around them.
- The structures which use galvanized products can last even more than 50 years in conditioned environments and for over 20 years, they can withstand severe water exposures as well.