Pipes are commonly joined by welding, using threaded pipe and fittings; sealing the connection with a pipe thread compound, Polytetrafluoroethylene (PTFE) Thread seal tape, oakum, or PTFE string, or by using a mechanical coupling.Process piping is usually joined by welding using a TIG or MIG process. The most common process pipe joint is the butt weld.
The most common pipe thread in North America is the National Pipe Thread (NPT) or the Dryseal (NPTF) version.
Plastic pipes may be joined by solvent welding, heat fusion, or elastomeric sealing. If frequent disconnection will be required, gasketed pipe flanges or union fittings provide better reliability than threads.Some thin-walled pipes of ductile material, such as the smaller copper or flexible plastic water pipes found in homes for ice makers and humidifiers, for example, may be joined with compression fittings. Underground pipe typically uses a "push-on" gasket style of pipe that compresses a gasket into a space formed between the two adjoining pieces. Push-on joints are available on most types of pipe.
Thus we avoid serious accidents which repair is often very expensive.
To define and secure boilers safely, some professional specialized organizations such as the American Society of Mechanical Engineers (ASME) develop standards and regulation codes..For instance, the ASME Boiler and Pressure Vessel Code is a standard providing a wide range of rules and directives to ensure compliance of the boilers and other pressure vessels with safety, security and design standards.5 Historically, boilers were a source of many serious injuries and property destruction due to poorly understood engineering principles.Thin and brittle metal shells can rupture, while poorly welded or riveted seams could open up, leading to a violent eruption of the pressurized steam.When water is converted to steam it expands to over 1,000 times its original volume and travels down steam pipes at over 100 kilometres per hour.Because of this, steam is a great way of moving energy and heat around a site from a central boiler house to where it is needed, but without the right boiler feed water treatment, a steam-raising plant will suffer from scale formation and corrosion. At best, this increases energy costs and can lead to poor quality steam, reduced efficiency, shorter plant life and unreliable operation. At worst, it can lead to catastrophic failure and loss of life. Collapsed or dislodged boiler tubes can also spray scalding-hot steam and smoke out of the air intake and firing chute, injuring the firemen who load the coal into the fire chamber. Extremely large boilers providing hundreds of horsepower to operate factories can potentially demolish entire buildings.A boiler that has a loss of feed water and is permitted to boil dry can be extremely dangerous.If feed water is then sent into the empty boiler, the small cascade of incoming water instantly boils on contact with the superheated metal shell and leads to a violent explosion that cannot be controlled even by safety steam valves. Draining of the boiler can also happen if a leak occurs in the steam supply lines that is larger than the make-up water supply could replace. The Hartford Loop was invented in 1919 by the Hartford Steam Boiler and Insurance Company as a method to help prevent this condition from occurring, and thereby reduce their insurance claimsÅ¹rÃ³dÅ‚o: https://en.wikipedia.org/wiki/Boiler#Safety